UrologySchool.com

TESTICULAR CANCER: GERM-CELL TUMOURS

Includes 2019 AUA Guidelines on Early Stage Testicular Cancer and 2010 CUA Consensus Statement on Germ Cell Tumours

Contents

Epidemiology
Risk factors
Pathology
Natural history
Diagnosis and Evaluation
Staging
Management
- Seminoma
- Non-seminoma
Special scenarios
Questions
Answers

Background

95% of testicular tumours are Germ Cell Tumours (GCTs)
- 5% of testicular tumours are non-germ cell tumours such as sex-cord stromal tumours, adenocarcinoma of the rete testis, and lymphoma
95% of GCTs originate in the testicle
- 5% of GCTs originate outside the testicle i.e. primary extra-gonadal GCT

Epidemiology

Incidence
- Relatively rare

Estimated incidence
- Worldwide 2020: 74,458 (compared to 1,414,259 for prostate)§
- US 2021: 9,470§
  - Accounts for 1-2% of cancers among males in the United States
Age
- Most common malignancy among males aged 20-40 years old
Race
- Incidence highest in whites and lowest in African-Americans

Mortality
- Worldwide 2020: 9,334§
- US 2021: 440§
- 5-year relative survival: 94.9% (compared to prostate 97.5%, bladder 77.1%, and kidney/renal pelvis 75.6%)§

Risk factors

Established risk factors (5):
1. Cryptorchidism
  - Ipsilateral testis: relative risk 4-6x; relative risk decreases to 2-3x if orchidopexy is performed before puberty
  - Contralateral testis: slightly increased risk (relative risk 1.74x)
2. Family history of GCT
3. Personal history of GCT
4. Gern Cell Neoplasia In-Situ (GCNIS), previously referred to as intratubular germ cell neoplasia (ITGCN) unclassified
  - All adult invasive GCTs arise from GCNIS, except spermatocytic seminoma.
  - Among males with GCNIS, the risk of developing invasive GCT is ≈50% at 5 years
  - GCNIS develops before birth from an arrested gonocyte
5. Race
  - Caucasian risk > African-American

Genetics

Increased number of copies of genetic material from the short arm of chromosome 12 is a universal finding in testicular and extra-gonadal germ cell tumors.

Pathology

Classification
- Pathological: GCNIS-derived vs. non-GCNIS-derived§
- Clinical: seminoma vs. NSGCT
  - GCTs that contain both NSGCT subtypes and seminoma are classified as NSGCTs
  - Clinical classification based on differences in management and outcome
Seminoma

Most common type of GCT
- Comprises 52-56% of all GCTs (NSGCT comprises 44-48%)
Occur at an older average age than NSGCTs, with most cases diagnosed in the 4th-5th decade of life
Arises from GCNIS and is considered to be the common precursor for the other NSGCT subtypes

Non-seminoma

Subtypes (4):
1. Embryonal carcinoma (EC)
  - Aggressive; associated with a high rate of metastasis, often in the context of normal serum tumor markers
  - Most undifferentiated cell type of NSGCT, with totipotential capacity to differentiate to other NSGCT cell types (including teratoma) within the primary tumor or at metastatic sites.
2. Choriocarcinoma
  - Rare
  - Aggressive; typically manifests with extremely highly elevated serum hCG levels
  - Commonly spreads by hematogenous routes
3. Yolk sac tumour
4. Teratoma

Spermatocytic seminoma

Accounts for <1% of GCTs.
Believed to have a different pathogenesis and separate cell of origin than classic seminoma
Does not arise from GCNIS, not associated with a history of cryptorchidism or bilaterally, does not demonstrate i(12p), and does not occur as part of mixed GCTs
Benign tumor; almost always cured with orchiectomy

Natural history

Rapidly growing tumours
Sites of metastasis
- Lymph nodes
  - Retroperitoneal lymph nodes
    - Most common site of metastasis
      - 70-80% of GCT metastasis occurs by lymphatic spread from the primary tumor to the retroperitoneal lymph nodes and subsequently to distant sites.
        
        Exception: choriocarcinoma, with a propensity for hematogenous dissemination.
        
        Pulmonary metastases of testicular GCT represents disease spread via the hematogenous route, whereas mediastinal and cervical metastases represent lymphatic spread.
  - Supraclavicular lymph nodes
  - Mediastinal lymph nodes
  - Inguinal lymph nodes in patients with previous scrotal violation
- Visceral
  - Lung
    - Second most common site of metastasis
    - Most common site of visceral metastases
    - Thoracic metastasis in the absence of retroperitoneal disease and/or elevated serum tumor markers is uncommon
  - Liver

Diagnosis and Evaluation

Mandatory investigations in a patient with unilateral or bilateral scrotal mass suspicious for testicular neoplasm:
1. History and Physical exam
2. Labs (1):
  1. Serum tumour markers
3. Imaging
  - Primary: scrotal US with doppler
  - Metastasis:
    - Regional: CT abdomen/pelvis
    - Distant: CT chest (CXR can be used instead of CT if CS I seminoma)
      - Bone scan and CT scan of the brain are indicated in patients with symptoms suggestive of central nervous system or bone involvement and in patients with poor prognosis disease.

History and Physical Exam
- History
  - Most common presentation of testicular cancer: painless testis mass
    - A firm intratesticular mass should be managed as a malignant neoplasm until proven otherwise and should be evaluated further with a scrotal ultrasound scan.
    - Differential diagnosis of a scrotal mass (7):
      1. Testicular neoplasm
      2. Epididymoorchitis
      3. Torsion
      4. Hematoma
      5. Paratesticular neoplasm (benign or malignant)
      6. Hernia
      7. Varicocele
      8. Spermatocele
  - At the time of diagnosis, metastasis (regional or distant) is present in 33% of cases of NSGCT and 15% of cases of pure seminoma, and symptoms related to metastatic disease are the presenting complaint in 10-20% of patients
- Physical exam
  - Genitourinary
    - Affected and normal contralateral testicle, noting relative size and consistency and palpating for any testicular or extra-testicular masses.
  - Sites of metastases
    - Supraclavicular lymph nodes
    - Inguinal lymph nodes, if prior inguinal or scrotal surgery
  - Gynecomastia
    - Occurs in 2% of males with GCT
    - Resulting from elevated serum hCG levels, decreased androgen production, and/or increased estrogen levels
Labs
- Tumour markers (A YET, B SEC)
  - AFP
    - At diagnosis, elevated in 50-70% of low-stage (CS I, IIA, and IIB) NSGCT and 60-80% of advanced (CS IIC and III) NSGCT
    - Produced by (3):
      1. Yolk sac
      2. EC
      3. Teratoma
      - Choriocarcinomas and seminomas do not produce AFP
        
        Clinical implication: pure seminoma in the primary tumor with an elevated serum AFP should be treated as NSGCT
    - Upper limit < 11 ng/mL
      - Despite most laboratories considering AFP > 8ng/mL to be abnormally elevated, a proportion of the population may have levels up to 15-25 ng/mL in the absence of any pathology; treatment decisions based solely on “elevated” AFP levels that are stable and <25 ng/mL is discouraged
    - Serum half-life: 5-7 days
    - Other causes of elevated AFP:
      1. Non-malignant liver disease (infectious, drug-induced, alcohol-induced, autoimmune)
      2. Hepatocellular carcinoma
      3. Cancers of the stomach, pancreas, biliary tract, and lung
      4. Ataxic telangiectasia
      5. Hereditary tyrosinemia
      6. Hereditary persistence of AFP (a congenital alteration in the hepatic nuclear factor binding site of the AFP gene)
  - β-hCG
    - At diagnosis, elevated in 20-40% of low-stage NSGCT and 40-60% of advanced NSGCT
    - Produced by (3):
      1. Seminoma (15% of cases)
      2. EC
      3. Choriocarcinoma
    - Upper limit: <5 mU/mL
    - Serum half-life: 24 to 36 hours (2019 AUA Update Peds Testis Tumours says 24-48 hours)
    - Other causes of elevated hCG:
      1. Hypogonadism
        
        LH will be elevated and can be a cause false-positive elevated hCC due to cross-reactivity of the hCG assay with LH
        
        Supplemental testosterone decreases LH levels, allowing accurate assessment of hCG levels thereafter§
      2. Cancers of the liver, biliary tract, pancreas, stomach, lung, breast, kidney, and bladder.
      3. Marijuana use
  - LDH
    - At diagnosis, elevated in ≈20% of low-stage GCT and 20-60% of advanced GCT
      - Magnitude of LDH elevation correlates with bulk of disease.
      - Least relevant and clinically applicable of the tumour markers
        
        Non-specific marker
        
        Main use in GCT is in the prognostic (S stage classification) assessment at diagnosis.
      - Treatment decisions based solely on LDH elevation in the setting of normal AFP and hCG should be discouraged.
    - Normal value 48-115 IU/liter
    - Serum half-life: 24 hours
    - LDH is expressed in smooth, cardiac, and skeletal muscles and can be elevated from cancerous (kidney, lymphoma, GI, breast) or non-cancerous conditions (heart failure, anemia, HIV)
  - Pre-orchiectomy markers
    - Uses (2):
      1. Support initial diagnosis
      2. Interpret tumor marker levels after orchiectomy.
    - Should not be used for staging and risk stratification
      - Can lead to over- or under-treatment with resulting excess rates of toxicity or relapse, respectively.
  - Post-orchiectomy markers
    - Uses (2):
      1. Evaluate for metastases in the case of persistently elevated/rising post-orchiectomy tumour markers
      2. Evaluate for recurrence during surveillance and after completion of therapy (chemotherapy, radiation, surgery).
Imaging
- Local: scrotal ultrasound with doppler
  - Clinical application
    - Evaluate both testicles; 2% incidence of bilateral GCT
      - In cases of bilateral GCT, a metachronous lesion is the most common presentation.
    - High-frequency transducers (5 to 10 MHz) can readily identify and distinguish intratesticular lesions a few millimeters in size from extra-testicular pathology
  - Indications in the context of GCT (3)
    1. Scrotal mass
    2. Suspected metastatic GCT with a normal testicular examination
      - A small, impalpable scar or calcification indicates a “burned-out” primary testis tumor.
    3. Suspected primary extra-gonadal GCT
    - Patients with normal serum tumor markers (hCG and AFP) and indeterminate findings on physical exam or testicular ultrasound for testicular neoplasm should undergo repeat imaging in 6-8 weeks.
  - Imaging findings
    - Typical GCT is hypoechoic

(a) Seminoma usually presents as a homogeneous hypoechoic nodule confined within the tunica albuginea.

(b) Sonography shows a large heterogeneous mass occupying nearly the whole testis but still confined within the tunica albuginea, it is rare for seminoma to invade to peritesticular structures.

Source: Wikipedia

Embryonal cell carcinoma. Longitudinal ultrasound image of the testis shows an irregular heterogeneous mass that forms an irregular margin with the tunica albuginea.

Source: Wikipedia

Testicular microlithiasis
- Significance
  - Unclear in the general population
    - If no history of GCT, risk of GCT is only increased if an additional established risk factor (see above) is present

Management
- No further evaluation or screening in incidentally detected microlithiasis

If established risk factor and testicular microlithiasis, counsel patient about the potential increased risk of GCT, need for periodic self-examination and follow-up with a medical professional

Testicular microlithiasis in a patient with contralateral orchiectomy due to testicular malignancy. Echogenic foci viewed in testis as small white spots.

Source: Wikipedia

MRI
- Can be considered an adjunct to scrotal ultrasound in patients with lesions suspicious for benign etiology
- Should not delay orchiectomy in patients in whom malignancy is suspected

Metastasis
- Regional
  - Regional lymph nodes comprises (7):
    1. Inter-aortocaval
    2. Para-aortic
    3. Para-caval
    4. Pre-aortic
    5. Pre-caval
    6. Retro-aortic
    7. Retro-caval
  - Modality
    - CT abdomen/pelvis with oral and IV contrast
      - Most effective imaging modality for regional staging
    - MRI
      - Alternative to CT
  - Imaging findings
    - Retroperitoneal lymph nodes
      - Pattern of lymph drainage in the retroperitoneum is from right to left.
        
        For right testis tumors, the primary drainage site is the inter-aortocaval lymph nodes inferior to the renal vessels, followed by the paracaval and para-aortic nodes.
        
        For left testis tumors, the primary drainage site is the para-aortic lymph nodes, followed by the inter-aortocaval nodes.

Right to left drainage pattern of retroperitoneal lymph nodes

Source: UrologySchool.com

"Borderline" retroperitoneal lymph nodes
- Lymph nodes 5-9 mm in the primary landing zone should be viewed with suspicion for regional lymph node metastasis, particularly if they are anterior to the great vessels
Limitations
- Understaging
  - 25-35% of patients with CSI NSGCT and a “normal” CT scan will be found to have pathologically involved retroperitoneal lymph nodes at RPLND
- Overstaging
  - 12-40% of patients with CS IIA and IIB disease will be found to have pathologically negative lymph nodes at RPLND

Distant
- Chest
  - Timing
    - Needed to complete staging in patients with confirmed GCTs
    - Should not delay orchiectomy
  - Modality: plain-film chest x-ray vs. CT
    - Chest x-ray
      - Indications (AUA 2019 Guidelines)
        
        Suspected clinical stage I seminoma; preferred over CT
        
        When tumor markers are normal, the rate of skip metastasis to the thorax in seminoma is close to 0%, and the addition of CT chest to chest x-ray is very unlikely to alter treatment decisions.
    - CT scan
      - Indications (3) (AUA 2019 Guidelines)
        
        NSGCT
        
        Skip metastases are more common in non-seminoma than seminoma.
        
        Elevated and rising post-orchiectomy markers (hCG and AFP)
        
        Any evidence of metastases on abdominal/pelvic imaging, chest x-ray or physical exam.
- Other
  - No role for routine bone scintigraphy or brain CT imaging at the time of diagnosis.
    - Visceral metastasis to bone and brain is uncommon in GCT in the absence of symptoms or other clinical indicators of disease.
    - A notable exception is brain CT imaging for patients with a highly elevated hCG (>10,000 mU/mL) because these levels are often associated with metastatic choriocarcinoma, which has a propensity for brain metastases.
- FDG-PET
  - Currently, no role in the routine evaluation of NSGCT and seminoma at the time of diagnosis.
Timing
- Management decisions should be based on Imaging studies performed within 4 weeks of the initiation of treatment due to the rapid growth of GCTs.

Other
- Testicular biopsy: contraindicated
  - Scrotal violation increases risk of (2):
    1. Pelvic or inguinal lymph node metastasis due to altered lymphatic drainage of the testicle
    2. Local recurrence

Staging

TNM (AJCC 8th edition§)
- T stage (primary tumor)
  - pTX: cannot be assessed
  - pT0: no evidence of primary tumour
  - pTis: germ cell neoplasia in situ
  - pT1: tumour limited to testis (including rete testis invastion) without lymphyovascular invasion (LVI)
    - For pure seminoma:
      - pT1a: tumour size < 3 cm
      - pT1b: tumour size ≥ 3 cm
  - pT2: tumour limited to testis (including rete testis invastion) with LVI or tumour invading hilar soft tissue, epididymis or tunica vaginalis
  - pT3: direct (continuous) spermatic cord soft tissue invasion
    - LVI of the spermatic cord without soft tissue invasion is not pT3
  - pT4: direct scrotum invasion
- N Stage (regional lymph node stage)
  - Clinical
    - cNX: regional lymph nodes cannot be assessed
    - cN0: no regional lymph node metastasis
    - cN1: metastasis with a lymph node mass ≤2 cm in greatest dimension OR multiple lymph nodes, none >2 cm in greatest dimension
    - cN2: metastasis with a lymph node mass >2 cm but ≤5 cm in greatest dimension OR multiple lymph nodes, any one mass >2 cm but ≤5 cm
    - cN3: metastasis with a lymph node mass >5 cm in greatest dimension
  - Pathologic
    - pNX: regional lymph nodes cannot be assessed
    - pN0: no regional lymph node metastasis
    - pN1: metastasis with a lymph node mass ≤2 cm in greatest dimension AND ≤5 positive nodes, none >2 cm in greatest dimension
    - pN2:
      - Metastasis with a lymph node mass >2 cm but ≤5 cm in greatest dimension OR
      - >5 nodes positive, none >5 cm in greatest dimension OR
      - Extranodal extension of tumour
    - pN3: metastasis with a lymph node mass >5 cm in greatest dimension
- Distant metastasis
  - MX: distant metastasis cannot be assessed
  - M0: no distant metastasis
  - M1a: non-regional lymph node (ex: iliac, inguinal, pelvic NOS) or lung metastasis
  - M1b: non-lung visceral metastasis
- Serum markers (S)
  - SX: serum tumor markers not available or not performed
  - S0: markers within normal limits
  - S1: LDH < 1.5 x upper limit of normal, hCG < 5,000 mIU/mL and AFP < 1,000 ng/mL
  - S2: LDH 1.5 - 10 x upper limit of normal OR hCG 5,000 - 50,000 mIU/mL OR AFP 1,000 - 10,000 ng/mL
  - S3: LDH > 10 x upper limit of normal OR hCG > 50,000 mIU/mL OR AFP > 10,000 ng/mL

Clinical staging

Prognosis of GCT and initial management decisions are determined by clinical stage (CS)
Based on (3):
1. Pathologic stage of the primary tumor
2. Presence and extent of regional and distant metastatic disease
3. Post-orchiectomy serum tumor marker levels
  - Serum tumor markers (AFP, hCG, and LDH) should be repeated at appropriate T1/2 time intervals after orchiectomy to determine nadir for staging and risk stratification
    - For patients with elevated AFP or hCG post-orchiectomy, clinicians should monitor serum tumor markers to establish nadir levels before treatment only if marker nadir levels would influence treatment.
Testicular cancer clinical stage groups

Stage grouping
Stage 0	pTis	N0	M0	S0
Stage I	pT1-T4	N0	M0	SX
Stage IA	pT1	N0	M0	S0
Stage IB	pT2 - pT4	N0	M0	S0
Stage IS	Any pT/TX	N0	M0	S1-3
Stage II	Any pT/TX	N1-N3	M0	SX
Stage IIA	Any pT/TX	N1	M0	S0
Stage IIA	Any pT/TX	N1	M0	S1
Stage IIB	Any pT/TX	N2	M0	S0
Stage IIB	Any pT/TX	N2	M0	S1
Stage IIC	Any pT/TX	N3	M0	S0
Stage IIC	Any pT/TX	N3	M0	S1
Stage III	Any pT/TX	Any N	M1a	SX
Stage IIIA	Any pT/TX	Any N	M1a	S0
Stage IIIA	Any pT/TX	Any N	M1a	S1
Stage IIIB	Any pT/TX	N1-N3	M0	S2
Stage IIIB	Any pT/TX	Any N	M1a	S2
Stage IIIC	Any pT/TX	N1-N3	M0	S3
	Any pT/TX	Any N	M1a	S3
	Any pT/TX	Any N	M1b	Any S

Overview of clinical staging:
- Clinical stage (CS) I: disease confined to the testis
- CS II: presence of regional (retroperitoneal) lymph node metastasis
- CS III: non-regional lymph node and/or visceral metastasis, although post-orchiectomy serum tumour marker levels can upstage patients from CSII to CSIII

Management

General principles
- Any post-pubertal male, regardless of age, should be treated according to adult treatment guidelines.
- Management decisions should be made in a multidisciplinary setting involving experienced clinicians in urology, medical oncology, radiation oncology, pathology, and radiology.
  - Review of primary tumor specimens by experienced pathologists is recommended.
    - Expert review of pathologic specimens should be considered in clinical scenarios where treatment decisions will be impacted.
      - In a randomized, multicenter clinical trial, 5 of 382 NSGCT specimens (1.3%) were reclassified as seminomas by centralized pathologic review
- Management decisions should be based on imaging obtained within the preceding 4 weeks and serum tumor markers (hCG and AFP) within the preceding 10 days.
  - Due to the rapid doubling time of many GCT, particularly NSGCT, there is a risk of disease progression between staging studies and intervention. Therefore, risk adapted management decisions (i.e. RPLND for Stage IIA disease) should be made based on recent imaging and serum tumor marker levels to avoid undertreatment.
- In patients with normal serum tumor markers (hCG and AFP) and equivocal imaging findings for metastasis, consider repeat imaging in 6-8 weeks to clarify the extent of disease prior to making a treatment recommendation.
- Prior to definitive management, patients should be counseled about the risks of (3):
  1. Hypogonadism
    - Hormone levels in long-term survivors of testicular cancer
      - Population: 1235 patients with history of unilateral orchiectomy for testicular cancer and adjuvant RPLND only, radiotherapy only, or chemotherapy
      - Compared to healthy controls
      - Results
        
        Approximately 11 years follow-up
        
        No significant difference in serum testosterone between testicular cancer patients and healthy controls
        
        Significantly higher age-adjusted LH in testicular cancer patients
      - Nord, Carina, et al."Gonadal hormones in long-term survivors 10 years after treatment for unilateral testicular cancer." European urology 44.3 (2003): 322-328.
    - Over long-term follow-up, up to 10-15% of patients will have low serum testosterone levels or will require testosterone replacement therapy
  2. Infertility
    - At diagnosis, up to 50% have impaired semen parameters and 10% are azoospermic
    - Sperm cryopreservation
      - Timing
        
        Pre-orchiectomy
        
        Consider in patients without a normal contralateral testicle or with known subfertility
        
        Post-orchiectomy
        
        Recommended before treatment (other than orchiectomy) is initiated in patients who are undecided or are planning future paternity.
        
        Virtually all patients become azoospermic after chemotherapy, and 50-80% of patients with normal semen parameters at diagnosis return to these levels within 2 and 5 years, respectively.
        
        Recovery of spermatogenesis after radiation therapy for seminoma may take to 2 to 3 years or longer.
        
        Consider in patients with a normal contralateral testicle or known fertility, who are undecided or are planning future paternity, given the potential risk of pathologic process (testicular cancer, trauma) involving contralateral testicle
  3. Contralateral tumour
    - Patients with a history of GCT or GCNIS should be informed of risks of a second primary tumor while rare is significantly increased in the contralateral testis

Orchiectomy
- See Orchiectomy Chapter Notes
- Radical inguinal orchiectomy
  - Testicular prosthesis should be discussed prior to orchiectomy.
  - Approach: inguinal
    - Trans-scrotal orchiectomy: contraindicated due to risks of scrotal violation (see above)
  - Patients suspected to have a testicular neoplasm should undergo a radical inguinal orchiectomy with removal of the tumor-bearing testicle and spermatic cord to the level of the internal inguinal ring.
    - In very rare cases where there is a possibility of a benign tumour, excisional biopsy with a frozen section should be performed prior to definitive orchiectomy to allow for the possibility of organ-sparing partial orchiectomy.
  - Timing
    - In general, orchiectomy should be performed prior to any further treatment.
      - Exception: in patients with life-threatening metastatic disease and an unequivocally elevated AFP and/or HCG, orchiectomy should not delay the start of chemotherapy and can be postponed until later in the treatment course
- Testis-sparing surgery (TSS)§
  - Not recommended in patients with a testicular lesion suspicious for malignant neoplasm and a normal contralateral testis; radical inguinal orchiectomy is recommended
  - Indications (3)
    1. Patients wishing to preserve gonadal function
    2. Mass <2cm
    3. And one of the following:
      1. Equivocal ultrasound/physical exam findings and negative tumor markers (hCG and AFP)
      2. Congenital, acquired or functionally solitary testis
      3. Bilateral synchronous tumors
  - Patients considering TSS should be counseled regarding (5):
    1. Higher risk of local recurrence
    2. Need for monitoring with physical examination and ultrasound
    3. Role of adjuvant radiotherapy to the testicle to reduce local recurrence
    4. Impact of radiotherapy on sperm and testosterone production
    5. Risk of testicular atrophy and need for testosterone replacement therapy, and/or subfertility/infertility
  - When TSS is performed, in addition to the suspicious mass, multiple biopsies of the ipsilateral testicle normal parenchyma should be obtained for evaluation by an experienced genitourinary pathologist to rule out GCNIS.
    - 50-80% undergoing TSS have concomitant GCNIS in the ipsilateral testis
    - GCNIS
    - If GSCNIS on testis biopsy or malignant neoplasm after TSS are found:
      - If patient prioritizes preservation of fertility and testicular androgen production, surveillance is recommended
        
        For patients with abnormal semen parameters but sufficient for assisted reproductive techniques, close surveillance with periodic ultrasound evaluation of the testis is a reasonable strategy with deferred therapy until successful pregnancy and/or development of GCT.
      - If patient prioritizes reduction of cancer risk, testicular radiation (18-20 Gy) or orchiectomy is recommended
        
        Radiation
        
        Advantage
        
        Reduces the risk of hypogonadism compared to orchiectomy
        
        Leydig cells are radioresist compared with germinal epithelium.
        
        Leydig cell function may decline over time, and 40% of men who receive radiation therapy require supplemental testosterone
        
        Disadvantage
        
        Increases risk of infertility
        
        For patients with a normal contralateral testis who desire future paternity, radical orchiectomy is preferred because scatter to the contralateral testis from radiotherapy may impair spermatogenesis.
        
        Radiation at these doses causes permanent sterility of the treated testis, but can be delayed in patients who wish to father children.
    - If GCNIS is not found on biopsy:
      - It is highly likely that GCNIS is present outside of the sampled tissue, and the patient should be followed with serial self-testicular exam, ultrasound, and tumor markers as appropriate.
  - Any local recurrence within the ipsilateral testis occurring with or without adjuvant therapy should be managed with completion radical orchiectomy
- Contralateral testis biopsy
  - An open inguinal biopsy of the contralateral testis may be considered in patients with risk factors for testicular cancer or patients with suspicious lesions on preoperative ultrasound scan
- Delayed orchiectomy
  - In a small subset of patients with widespread and/or symptomatic GCT, the diagnosis is made based on biopsy of a metastatic lesion or empirically based on clinical and serologic features. In these unique settings, initiation of systemic chemotherapy supersedes diagnostic orchiectomy. Because of high discordance of pathologic response rates within the testicle, a delayed orchiectomy is recommended for all patients with NSGCT after induction chemotherapy, even in the setting of a complete response in the retroperitoneum
  - The role of delayed orchiectomy is more controversial in patients with presumed primary retroperitoneal/extragonadal GCT.
    - Radical orchiectomy has been advocated when the metastatic pattern of retroperitoneal disease lateralizes to the expected distribution of a testicular primary.
Post-orchiectomy management

Based on histology (seminoma vs. NSGCT) and clinical stage
General principles
- Newly elevated and/or rising serum tumor marker levels after orchiectomy indicate the presence of metastatic disease, and these patients should receive induction chemotherapy.
- In the setting of a negative metastatic evaluation and slowly declining markers (i.e., not according to half-life), patients should be monitored closely and have levels checked periodically until the levels normalize or begin to rise.
- Surveillance for clinical stage I disease
  - Advantages (1):
    - Potentially reducing treatment-related toxicity by restricting treatment to patients with a proven need for it.
      - Radical orchiectomy alone has high cure rate in patients with CSI GCT (80-85% for CS I seminoma and 70-80% for CSI NSGCT)
        
        Patients that relapse on surveillance have excellent outcomes with salvage therapy.
  - Disadvantages (4):
    1. Highest risk of relapse (compared to adjuvant treatment)
    2. Need for long-term (>5 years) surveillance
    3. Risk of second malignant neoplasms owing to intensive surveillance CT imaging
    4. More intensive therapy required to treat patients at the time of relapse than if they had received treatment at diagnosis
- Radiotherapy
  - Seminoma are sensitive to radiation therapy
  - Radiation therapy has no role in NSGCT with the exception of treatment for brain metastases.
- Chemotherapy
  - International Germ Cell Cancer Collaborative Group (IGCCCG) risk classification
    - Used over the TNM system to select the chemotherapy regimen and number of cycles in patients receiving chemotherapy for advanced disease
      - Developed in patients with metastatic GCT at the time of diagnosis and is NOT applicable to patients with relapsed GCT
    - In NSGCT, IGCCCG risk classified based on (3):
      1. Presence of non-pulmonary visceral metastasis
      2. Primary mediastinal NSGCT
      3. TMs at the initiation of chemotherapy (not levels measured before orchiectomy)
    - In seminoma, IGCCCG risk classified based on (1):
      1. Presence of non-pulmonary visceral metastasis
        
        No poor prognosis category

Histology	Good prognosis	Intermediate prognosis	Poor prognosis (II or greater)
Non-seminoma	Testis/retroperitoneal primary AND No non-pulmonary visceral metastases AND Good markers AFP < 1000 ng/mL AND hCG < 5,000 IU/L (1,000 ng/mL) AND LDH < 1.5 x upper limit of normal (CSI-IIIa)	Testis/retroperitoneal primary AND No non-pulmonary visceral metastases AND Intermediate markers: AFP≥ 1,000 and ≤ 10,000 ng/mL OR hCG ≥ 5,000 IU/L and ≤ 50,000 IU/L OR LDH ≥ 1.5 x N and ≤ 10 x N (CSIIIb)	Mediastinal primary OR Non-pulmonary visceral metastases OR Poor markers: AFP > 10,000 ng/mL OR hCG > 50,000 IU/L (10,000 ng/mL) OR LDH > 10 x upper limit of normal (CSII or greater)
Seminoma	Any primary site AND No non-pulmonary visceral metastases AND Normal AFP, any hCG, any LDH	Any primary site AND Non-pulmonary visceral metastases AND Normal AFP, any hCG, any LDH

During chemotherapy, patients need to be monitored on a regular basis with serial tumour marker estimation.
Post-chemotherapy, radiological restaging should be performed in all patients.
- If the expected tumour marker decline is seen, all residual masses should be treated appropriately.
- If the tumour markers plateau and are at a low level, they should be followed closely.
- If there is a persistent plateau or tumour marker decline, residual masses should be treated appropriately.
Markedly elevated HCG prior to treatment may take longer to normalize or plateau at the end of chemotherapy

RPLND

See RPLND Chapter Notes

Seminoma

CSIA and IB Seminoma

Options (3):

Preferred (1): surveillance
Alternatives (2):
1. Adjuvant primary radiotherapy (20 Gy to the para-aortic region)
2. Adjuvant primary chemotherapy with single-agent carboplatin (1 cycle)
Both 2019 AUA and 2010 CUA guidelines recommend surveillance, adjuvant as an alternative
- If adjuvant treatment is chosen
  - CUA recommends radiotherapy over chemotherapy
  - EAU recommends against radiotherapy
  - SWONTECA recommends radiotherapy only if chemotherapy not suitable
Long-term survival rates approaching 100% for each approach
Surveillance for clinical stage I seminoma
- 80-85% of patients with clinical stage I seminoma achieve cure with radical orchiectomy alone
- Protocol varies by institution, no consensus
  - History and physical examination: every 4-6 months for the first 2 years, and then every 6-12 months in years 3-5.
  - Cross-sectional imaging of the abdomen with or without the pelvis: every 4-6 months for the first 2 years, and then every 6-12 months in years 3-5.
  - Imaging of the chest and serum tumor marker assessment can be obtained as clinically indicated.
    - Compared with NSGCT, surveillance for CS I seminoma is complicated by the limited utility of serum tumor markers to detect relapse
- Risk factors for relapse on surveillance (2):
  - Tumor size >4 cm
  - Rete testis invasion
- Patients who relapse on surveillance should be fully restaged and treated based on their TNM-s status.
Adjuvant primary radiotherapy
- Delivered as dog-leg (retroperitoneum and ipsilateral pelvis) vs. para-aortic region
  - Dog-leg
    - Outcomes
      - In-field recurrence after dog-leg radiotherapy occurs in <1%.
        
        Most common sites of recurrence are the thorax and left supraclavicular fossa.
        
        Virtually all recurrences are cured with first-line chemotherapy.
      - Persistent oligospermia after dog-leg radiotherapy occurs in 8%
    - Advantage
      - Does not require serial follow-up CT imaging after treatment
  - Para-aortic
    - Advantage
      - Smaller field and dose.
    - Disadvantage
      - Requires serial follow-up CT imaging after treatment
  - Dog-leg vs. para-aortic
    - RTC found para-aortic to be non-inferior to dog-leg radiotherapy in CSI seminoma§
Adjuvant primary chemotherapy
- Cisplatin is inferior to carboplatin for CSI seminoma
- Patients require serial follow-up CT imaging

CS IIA and IIB Seminoma

≈15-20% of patients with seminoma have CS II disease at diagnosis; 70% of these patients have CS IIA and IIB.
CSIIA:
- CUA: Dog-leg radiotherapy (25-35 Gy) preferred over first-line chemotherapy (BEP×3 or EP×4)
- AUA: radiotherapy or chemotherapy
CSIIB:
- CUA: depending on bulk of disease and location of lymph nodes, radiation or chemotherapy [good risk chemotherapy BEP×3 or EP×4] can be used.
  - First-line chemotherapy is recommended for bulky (>3 cm) and/or multifocal retroperitoneal metastases
- AUA:
  - CSIIB with lymph node ≤3cm: radiotherapy or chemotherapy
  - CSIIB with lymph node >3cm: chemotherapy
Routine surveillance CT imaging is unnecessary after complete resolution of disease.

CSIIC and III seminoma

Regimen and number of cycles are based on IGCCCG risk classification (see above)

Good-risk: BEP×3 or EP×4
Intermediate-risk: BEP×4

Special scenarios
- Residual masses after radiotherapy for seminoma
  - Patients should undergo biopsy and histologic confirmation of the suspected lesion before management decisions are made.
    - Although rare, seminoma may transform into NSGCT elements, and this should be considered in patients with metastatic seminoma who fail to respond to conventional therapy.
    - Either an open or a laparoscopic biopsy of the para-aortic mass is an acceptable approach if CT-guided biopsy is not feasible or the result is nondiagnostic.
    - RPLND should not be performed without histologic confirmation of NSGCT pathology.
- Residual masses after chemotherapy for seminoma
  - After first-line chemotherapy, 60-80% of patients have radiologically detectable residual masses.
  - Histology of residual masses:
    - Necrosis 90%
    - Viable malignancy: 10%
    - Recall for NSGCT, histology of post-chemotherapy residual masses demonstrates necrosis in 40%, viable disease in 15%, and teratoma in 45%
  - Management
    - In seminoma, most residual masses do not need to be treated.
      - Spontaneous resolution of post-chemotherapy residual masses is reported in 50-60% of cases, and the median time to resolution is 13-18 months.
      - Post-chemotherapy surgery for seminoma is technically difficult (and frequently not feasible) because of the desmoplastic reaction that occurs after chemotherapy with resultant increased perioperative morbidity.
      - Teratoma and malignant transformation are much less of a concern with advanced seminoma.
    - If residual masses > 3 cm, evaluate further with FDG-PET
      - If FDG-PET positive: post-chemotherapy surgery
      - If FDG-PET negative: observation.
    - If residual masses< 3 cm: observation.
    - Post-chemotherapy radiotherapy has no role in the management of residual masses
- Relapse of seminoma
  - If chemo-naïve:
    - Patients relapsing on surveillance should receive primary radiotherapy
    - Patients with CSI or II seminoma treated with radiotherapy, or those on surveillance that relapse with bulky (>3 cm) retroperitoneal masses and systemic relapse should receive first-line chemotherapy based on ICCCG risk category
      - Salvage rates approach 100%.
  - If early relapse after chemotherapy: salvage chemotherapy
    - An important consideration for patients with advanced seminoma who relapse after first-line chemotherapy is the potential for teratoma at the site of relapse.
    - Patients with normal serum tumor markers should undergo biopsy before starting second-line chemotherapy.

NSGCT

CSIA and IB NSGCT

Options:
1. Surveillance
2. Adjuvant primary RPLND
3. Adjuvant primary chemotherapy (BEPx1-2)

Newer guidelines, such as 2019 AUA guidelines, recommend 1 cycle for CSIA and 2 cycles for CSIB
2010 CUA Consensus Statement: BEPx2

Long-term survival approaches 100% for each
Guidelines:
- 2010 CUA Consensus Statement: surveillance preferred for all CSI NSGCT
- 2019 AUA Guidelines:
  - CSIA NSGCT: surveillance recommended
  - CSIB NSGCT: all options are recommended
  - RPLND is recommended if there is any secondary somatic malignancy (e.g. rhabdomyosarcoma, adenocarcinoma, or primitive neuroectodermal tumor) in the primary tumor

Surveillance for clinical stage I NSGCT

70-80% of patients with clinical stage I seminoma achieve cure with radical orchiectomy alone
Risk factors for relapse on surveillance (2):
1. Pre-dominant embryonal carcinoma
2. Lymphovascular invasion

The definition of EC predominance in the literature varies from 45-90%.
Other identified risk factors include advanced pT stage, absence of mature teratoma, absence of yolk sac tumor, presence of EC (regardless of the percent composition), percentage of MIB-1 staining, tumor size, and patient age.

Surveillance protocol varies by institution, no consensus
- History and physical examination: every 2-3 months in year 1, every 2-4 months in year 2, every 4-6 months in year 3, and every 6-12 months for years 4 and 5
- Serum tumor markers (AFP, hCG +/- LDH): every 2-3 months in year 1, every 2-4 months in year 2, every 4-6 months in year 3, and every 6-12 months for years 4 and 5
- Radiologic assessment (chest x-ray and imaging of the abdomen with or without the pelvis): every 3-6 months in year 1 starting at 3 months, every 4-12 months in year 2, once in year 3, and once in year 4 or 5.
  - Men at higher risk of relapse (e.g., lymphovascular invasion) should be imaged with shorter intervals.
  - >90% of relapses occur within the first 2 years, but late relapses (>5 years) are seen in 1% of patients; after this time, annual serologic and radiographic assessment may be performed as indicated based upon clinical concerns.
    - Compared with NSGCT, surveillance for CS I seminoma is needed for a longer period because 10% to 20% of relapses occur 4 years or more after diagnosis.
Patients who relapse on surveillance should be fully restaged and treated based on their TNM-s status.
Early and late relapses have similar prognosis

Adjuvant primary RPLND
- Primary RPLND should be performed with curative (rather than staging) intent in all patients.
- Full, bilateral template dissection is associated with the lowest risk of abdominopelvic recurrence (<2%) and the highest rate of antegrade ejaculation (>90%) when nerve-sparing techniques are employed.

A multi-center randomized trial comparing primary RPLND to chemotherapy for CS I found that chemotherapy was associated with a lower risk of relapse. The relapse rate after primary RPLND in this trial was 11%, higher than other published series, suggesting that RPLND should be performed in experienced centers.

Adjuvant primary chemotherapy
- BEP x 1-2 is typically used.
- Advantages (2):
  1. Highest relapse-free survival with any single treatment modality
  2. Can be delivered at community-based institutions
- Disadvantages (4):
  1. Does not treat retroperitoneal teratoma
  2. Long-term surveillance CT imaging of the retroperitoneum is required
  3. Potential risk of late toxicity (see below).
  4. Exposes patients to the potential for chemoresistant and/or late relapse

CSIS NSGCT

Defined as the presence of elevated serum tumor markers after orchiectomy without clinical or radiographic evidence of metastatic disease.
Should be treated similarly to patients with CS IIC and III and receive induction chemotherapy according to IGCCCG classification.

CS IIA and IIB NSGCT

CSIIA with positive markers or CSIIB regardless of markers: primary chemotherapy (recommended by both CUA and AUA)

CUA: Elevated AFP or hCG levels after orchiectomy or bulky lymph nodes (>3cm) are risk factors for recurrence after primary RPLND. Therefore, patients with CS IIA and IIB NSGCT and elevated AFP or hCG levels or bulky lymph nodes (>3 cm) should receive induction chemotherapy.
AUA: Clinicians may offer RPLND as an alternative to chemotherapy to select patients with clinical stage IIB NSGCT with normal post-orchiectomy serum AFP and hCG.

CSIIA disease without marker elevation
- Substantial proportion of men with clinical stage IIA NSGCT are over-staged
- Minority of men with clinical stage IIA are upstaged to pathological stage IIB and may be advised to receive two cycles of adjuvant chemotherapy
- CUA: RPLND (with or without adjuvant chemotherapy) or surveillance with surgery for stable or growing lesions (if becomes marker positive use primary chemotherapy)
- AUA: RPLND or chemotherapy
Management after primary RPLND for NSGCT based on pathology (2021 NCCN TEST-10/2019 AUA):
- pN0: surveillance
- pN1: surveillance (preferred) vs. chemotherapy (BEP x2 or EP x2)
- pN2: chemotherapy (BEP x2 or EP x2) (preferred) vs. surveillance
- pN3: chemotherapy (BEP x3 or EP x4)
- pN1-3 pure teratoma: surveillance
- Immediate vs. deferred chemotherapy for pathological stage II disease after primary RPLND
  - Population: 195 males found to have positive nodes, (pathologically stage II) after primary RPLND (in whom the procedure was indicated). Nodes had to be considered completely resected and tumor markers had to be normal after primary RPLND.
  - Randomized to immediate vs. delayed chemotherapy (cisplatin/vinblastine/bleomycin +/- dactinomycin/cyclophosphamide)
  - Results:
    - Median follow-up: 4 years
    - Relapse rate at 2 years: 6% immediate vs. 49% delayed chemotherapy
    - Cancer-specific deaths: 1 immediate vs. 3 delayed chemotherapy
    - Death from all causes: 5 immediate vs. 3 delayed chemotherapy
  - Conclusions: immediate chemotherapy in patients found to have pathological stage II after primary RPLND reduces risk of relapse, but no significant difference in cancer-specific or overall survival (though really few deaths)
  - Williams, Stephen D., et al."Immediate adjuvant chemotherapy versus observation with treatment at relapse in pathological stage II testicular cancer." New England Journal of Medicine 317.23 (1987): 1433-1438.
Disadvantage of chemotherapy for metastatic NSGCT
1. Teratoma is resistant to chemotherapy
- RPLND is preferred as initial therapy in patients at risk for retroperitoneal teratoma who are at otherwise low risk for systemic disease (normal serum tumor markers, lymphadenopathy <3 cm).
- Unresected teratoma has the potential to exhibit rapid growth (growing teratoma syndrome), undergo malignant transformation, or cause late relapse, all of which may have lethal consequences.
Growing teratoma syndrome
- Should be considered if there is an expected tumour marker decline during chemotherapy but the metastases are growing radiologically

Management
- 2010 CUA Guidelines: In most cases, the full course of chemotherapy should be completed and resection of the growing and residual masses should be done post-chemotherapy.
  - Very rarely, rapid radiological progression in the setting of decreasing tumour marker decline is seen which would necessitate surgical resection prior to the completion of chemotherapy.
    - Similar description in 2018 AUA Update on on Medical and Surgical Management of Advanced Testis Cancer
    - Campbell's 11th edition, Chapter 34, page 805: Special mention is made of patients with declining or normalized serum tumor markers during first-line chemotherapy with enlarging (usually cystic) masses. These patients are considered to have growing teratoma syndrome. In these rare cases, chemotherapy is temporarily interrupted, and patients are taken for surgical resection. With complete surgical resection, the long-term prognosis for these patients is favorable

CS IIC and III NSGCT

Induction chemotherapy with cisplatin-based regimens
- Regimen and number of cycles are based on IGCCCG risk classification (see above)
  - Good risk NSGCT: BEP×3 or EP×4
    - 5-year OS is 91-94%
  - Intermediate or poor risk NSGCT: BEP×4
    - 5-year OS is 79% for intermediate-risk patients and 48% for poor-risk patients.
    - VIP×4 may be substituted for BEP×4 in patients with compromised pulmonary function and in patients in whom extensive chest surgery is likely to be performed to remove residual disease after chemotherapy

Special scenarios
- Residual masses after chemotherapy for NSGCT
  - After receiving first-line cisplatin-based chemotherapy, 5-15% of patients will have partial remission with positive tumour markers or have disease progression.
  - Management
    - If serum tumour markers elevated after induction chemotherapy, in general patients should receive salvage chemotherapy
    - If serum tumour markers normal and
      - Residual mass >1 cm: resection of residual mass
      - Residual mass <1 cm: controversial management
    - If the mass was retroperitoneal, a full bilateral template RPLND should be performed.
    - PC-RPLND in NSGCT
      - Distribution of histology§:
        
        Necrosis/fibrosis (40%)
        
        Teratoma (45%)
        
        Viable (15%) malignancy (with or without teratoma)
        
        ≈6-8% of post-chemotherapy surgery specimens contain evidence of non-GCT malignancy arising from malignant transformation of teratoma
        
        While those with necrosis could theoretically avoid post-chemotherapy surgery, necrosis only in the retroperitoneum cannot be predicted with sufficient accuracy to obviate safely the need for post-chemotherapy surgery in patients with residual masses.
        
        Pure embryonal carcinoma in the primary tumour is the best predictor of fibrosis only in the retroperltoneum
        
        90% long-term survival with fibrosis and/or teratoma only at PC-RPLND vs. 50-70% for patients demonstrating viable GCT at PC-RPLND
      - If PC-RPLND pathology demonstrates (2021 NCCN TEST-12)
        
        Teratoma or necrosis/fibrosis: surveillance
        
        Viable disease (e.g. residual embryonal carcinoma, yolk sac, choriocarcinoma, seminoma) in PC-RPLND pathology: 2 cycles chemotherapy (EP (etoposide/ciplatin), TIP (paclitaxel, ifosfamide, cisplatin), VIP (etoposide, ifosfamide, cisplatin), or VeIP (vinblastine, ifosfamide, cisplatin) [2021 NCCN Guidelines]
  - FDG-PET has no role in the assessment of patients with NSGCT and residual masses after chemotherapy
  - Patients with residual masses at multiple anatomic sites (retroperitoneum, chest, and left supraclavicular fossa are the most common) and normal tumour markers should undergo resection of all sites of measurable residual disease.
    - RPLND should be performed before post-chemotherapy surgery at other sites because the probability of residual disease in the retroperitoneum is highest, and RPLND histology is a strong predictor of histology at other sites.
      - If RPLND histology shows
        
        Viable malignancy, then patient should undergo chemotherapy
        
        Fibrosis, then patient should undergo surveillance or resection
        
        Teratoma, then patient should undergo resection.
- Relapsing NSGCT
  - Treatment depends on what treatment the patient previously received and, in certain cases, the location of the relapse.
  - Chemotherapy-naïve:
    - First-line chemotherapy based on ICCCG risk classification
    - Cure rates > 95%
    - Select CS I patients on surveillance who relapse in the retroperitoneum with non-bulky (<3 cm) tumor and normal serum tumor markers may be treated by induction chemotherapy or RPLND (particularly if teratoma was present in the primary tumor)
  - Relapse after chemotherapy:
    - Salvage-line chemotherapy.
    - Patients with serologic complete response to second-line chemotherapy with residual masses should undergo surgical resection after salvage chemotherapy.
      - Patients with viable malignancy in post–salvage chemotherapy surgical specimens have a particularly poor prognosis, and their survival is not improved with the use of postoperative chemotherapy.
    - In general, late relapse is resistant to chemotherapy, and the outcome is related to the ability to render patients disease-free by complete surgical resection
- Scrotal exploration
  - Patients found to have NSGCT in orchiectomy pathology following scrotal exploration require further treatment
    - Low-stage NSGCT: wide excision of scrotal scar and removal of spermatic cord.
    - High-stage NSGCT: systemic therapy will be given and therefore hemiscrotectomy is not needed

Treatment related sequelae

Early toxicity

Chemotherapy
- Cisplatin is associated with fatigue, myelosuppression, infection, peripheral neuropathy, hearing loss, diminished renal function, and death.
Radiation
- Associated fatigue, nausea and vomiting, leukopenia, and dyspepsia

Late toxicity

Hypogonadism
- Occurs in
  - 10-20% of patients treated with orchiectomy alone
  - 15-40% of patients treated with radiation therapy
  - 20-25% of patients treated with first-line chemotherapy regimens
- Serum AM testosterone and luteinizing hormone levels should be measured in patients with signs and symptoms of hypogonadism
Infertility
- Most males are able to have biological children after treatment for GCT but paternity rates are lower for men treated with radiation therapy and/or chemotherapy
Cardiovascular disease
- Risk increased with either subdiaphragmatic radiation or platinum-based chemotherapy
- Patients should establish regular care with a primary care physician so that modifiable risk factors for cardiovascular disease (e.g., diet, exercise, smoking, serum lipid levels, blood pressure, serum glucose) can be monitored.
Secondary malignancy
- Risk increased with either subdiaphragmatic radiation or platinum-based chemotherapy
- Patients should establish regular care with a primary care physician for appropriate health care maintenance and cancer screening as appropriate.
Chemotherapy specific
- Bleomycin is associated with pulmonary complications (including pulmonary fibrosis) and Raynaud phenomenon, but has only mild myelosuppressive effects at high doses.
- Cisplatin is associated with nephrotoxicity and neurotoxicity.
- Other long-term sequelae of chemotherapy include peripheral neuropathy and hearing loss

Special scenarios

Brain metastases

Associated with choriocarcinoma; should be suspected in any patient with a very high serum hCG level
- Choriocarcinomas are highly vascular and tend to hemorrhage during chemotherapy, with death rates of 4-10% secondary to intracranial hemorrhage
Management
- Brain metastases at diagnosis: BEP×4 chemotherapy followed by resection of residual masses.
- Relapse in the brain after first-line chemotherapy: second-line chemotherapy followed by resection and/or radiation therapy
  - Relapse in the brain after achieving a complete response to chemotherapy have a worse prognosis than patients with brain involvement at diagnosis.

Primary extra-gonadal GCTs
- Site of origin of GCTs: gonadal (95%) vs. extra-gonadal (5%)
- Develop in midline anatomic locations
  - Most common sites (descending order) of origin: mediastinum, retroperitoneum, sacrococcygeal region, and pineal gland, although many unusual sites have also been reported [SASP 2014]
  - Primary mediastinal GCT
    - Non-seminoma GCT (NSGCT)
      - Compared to NSGCTs originating in the testicle or retroperitoneum, primary mediastinal NSGCTs are (4):
        
        More likely to have yolk sac tumour components and be associated with elevated AFP
        
        Associated with Klinefelter syndrome
        
        Less sensitive to chemotherapy
        
        Associated with a poor prognosis
    - Seminoma
      - Primary mediastinal seminomas have similar prognosis to testicular seminomas
  - Primary retroperitoneal GCT
    - Behave similarly to testicular GCTs and carry the same prognosis.
- Of patients with metastatic GCT without a testis mass:
  - 1/3 definitively have a primary extra-gonadal GCT
  - 1/3 have ITGCN in the testis
  - 1/3 have sonographic evidence of a “burned-out” primary tumor
- Diagnosis and evaluation
  - If midline mass in male age < 40, consider GCT
    - Midline mass in male age < 40 with elevated AFP and/or hCG is diagnostic of GCT, even if testicular evaluation is normal; histologic confirmation by biopsy is unnecessary before starting treatment
    - Midline mass in male age < 40 with normal serum tumor markers, perform biopsy of the midline mass to confirm the diagnosis before beginning treatment
- Management
  - Inguinal orchiectomy
    - Indications in patients with suspected extra-gonadal GCT (2):
    1. Pattern of metastasis is consistent with a right-sided or left-sided testicular primary tumor
    2. Sonographic evidence of a “burned-out” primary tumor
Small (<10 mm), impalpable intratesticular lesions in the absence of disseminated GCT or elevated serum tumor markers
- Diagnostic dilemma
- Most of these lesions are benign (testicular cysts, small infarcts, or small Leydig cell or Sertoli cell tumors), however, 20-50% may represent small GCTs (usually seminomas).
  - Risk of malignancy increases with the size of the lesion.
- Management options (3):
  1. Inguinal orchiectomy
  2. Testis-sparing surgery involving inguinal exploration and excision (with frozen-section analysis to rule out GCT)
    - Intraoperative ultrasonography is useful during surgical exploration of the testis to locate the lesion.
  3. Close observation with serial ultrasound scans (with exploration of growing lesions).

Questions

Which subtypes comprise non-seminoma germ-cell tumours?
What percentage of patients are found to have metastatic disease at the time of diagnosis?
Which tumours secrete AFP? hCG? What is the half-life of these tumour markers?
What is the primary landing zone of a left vs. right primary testicular tumour?
What is the management of a post-chemotherapy retroperitoneal mass?

Answers

Which subtypes comprise non-seminoma germ-cell tumours?
What percentage of patients are found to have metastatic disease at the time of diagnosis?
Which tumours secrete AFP? hCG? What is the half-life of these tumour markers?
What is the primary landing zone of a left vs. right primary testicular tumour?
What is the management of a post-chemotherapy retroperitoneal mass?

References

Wein AJ, Kavoussi LR, Partin AW, Peters CA (eds): CAMPBELL-WALSH UROLOGY, ed 11. Philadelphia, Elsevier, 2015, chap 34
Stephenson, Andrew, et al. "Diagnosis and treatment of early stage testicular cancer: AUA guideline." The Journal of urology 202.2 (2019): 272-281.
Wood, Lori, et al."Canadian consensus guidelines for the management of testicular germ cell cancer." Canadian Urological Association Journal 4.2 (2010): e19.