Bladder and Testis Oncology

Rhabdomyosarcoma (RMS) edit

Epidemiology
- Most common soft-tissue sarcoma in children
Genetics
- Most cases are considered to be sporadic
- Genetic syndromes associated with RMS:
  - Li-Fraumeni syndrome
  - Neurofibromatosis
  - Basal cell nevus syndrome
  - Costello syndrome
  - Noonan syndrome
  - Multiple endocrine neoplasia type 2A
Pathology and molecular biology
- Histologic categories (3):
  1. Embryonal
    - Most common form of bladder or prostate RMS.
  2. Alveolar
    - Uncommon in the bladder or prostate
    - Two distinct types, PAX-FOXO1 fusion positive and negative, and fusion-positive tumors carry a worse prognosis
  3. Undifferentiated
Management
- Radical surgery may be required if there is lack of response to non-operative treatment.
Prognosis
- Prognostic factors
  - Site of origin
    - Prostate has the worst prognosis
    - Vaginal has best prognosis
  - Histology
    - Embryonal histology associated with improved prognosis compared to alveolar

Urothelial carcinoma of the Bladder edit

Uncommon
Lesions are unifocal, typically low grade and not prone to recurrence
Management
- Treatment consisting of resection only is adequate. Adjuvant treatment is not given.
- Surveillance cystoscopy is not needed; ultrasound is remarkably accurate and is an adequate surveillance strategy

Testicular Tumors edit

More likely benign in pre-pubertal males (in contrast to post-pubertal males where most testicular tumours are malignant)
Epidemiology
- The most common pathologic diagnosis in children with a testicular mass is a YST, followed by teratoma
Germ Cell Tumors
- Pathology
  - Tertatoma
    - According to some series, teratomas are the most common testicular tumor in children and consist of variable combinations of the three primitive embryologic germ cell layers [contradicts above]
    - Consist of variable combinations of the three primitive embryologic germ cell layers
    - Do not express AFP
    - In contrast to teratoms in post-pubertal males, most teratomoas in pre-pubertal male are benign, consisting of mature elements only, and do not metastasize
    - Preferred treatment for suspected teratoma is partial orchiectomy
  - Epidermoid cysts
    - Benign lesion; represent a monolayer teratoma
    - May account for >15% of prepubertal testis lesions
    - Do not express AFP
    - Preferred treatment for suspected epidermoid cysts is partial orchiectomy
    - No surveillance is required after treatment
  - Yolk-sac tumour (YST)
    - Pathology
      - Schiller-Duval bodies consist of a central blood vessel surrounded by two layers of tumor cells
        Pathognomonic for YSTs.
    - AFP levels are elevated
    - When metastases occur, YSTs often exhibit hematogenous spread to the lungs, without retroperitoneal disease. For these reasons retroperitoneal lymph node dissection (RPLND) plays very little role in pre-pubertal YST.
      - RPLND is used exclusively for patients with a residual retroperitoneal mass or persistently elevated AFP after chemotherapy and orchiectomy
- Presentation, Evaluation, and Staging
  - See CW11 Figure 156-7
  - Ultrasonography
    - Teratomas
      - Heterogeneous complex lesions and may contain cystic and solid components.
      - Bony elements appear as calcifications with shadowing.
      - Adipose tissue appears as echogenic areas without shadowing.
    - Epidermoid cysts
      - Characteristic appearance described as “onion skin” comprised of concentric rings of alternating hypoechoic and hyperechoic lesions.
    - YSTs
      - Typically well circumscribed and heterogeneous in appearance.
      - May appear hypervascular and may have areas of hemorrhage and necrosis.
    - Sertoli and Leydig cell tumors
      - Similar in appearance
      - Commonly manifest as a well-circumscribed hypoechoic mass.
  - Labs
    - Tumour markers
      - Interpretation of AFP levels in infants undergoing evaluation for a testis mass must be performed with caution as a result of the physiologically persistent elevation of AFP in infants age < 1
Tumors Associated with Disorders of Sexual Differentiation
- See Disorders of Sexual Differentiation Chapter Notes
- Patients with dysgenetic testis or hypovirulization have an increased incidence of testicular tumors
Gonadal Stromal Tumors
- Juvenile granulosa cell tumors
  - Most common testicular tumors affecting neonates
- Leydig cell tumors
  - Hormonally active; associated with precocious puberty.
- Sertoli cell
  - Usual presentation is a painless mass
  - Associated with endocrinologic and genetic syndromes such as Peutz-Jeghers and Carney syndromes
  - 10% are hormonally active
Leukemia and Lymphoma
- The most common cancers with metastases to the testis are leukemia and lymphoma

Paratesticular Rhabdomyosarcoma edit

Arises from the testicular tunicae, epididymis, or spermatic cord.
Up to 40% of paratesticular lesions are due to RMS
Management
- Multimodal involving surgery and chemotherapy with vincristine, dactinomycin, and cyclophosphamide
- Children age > 10 should undergo a staging ipsilateral retroperitoneal lymph node dissection, and not observation, because of a high occurrence of retroperitoneal failure

References edit

Wein AJ, Kavoussi LR, Partin AW, Peters CA (eds): CAMPBELL-WALSH UROLOGY, ed 11. Philadelphia, Elsevier, 2015, vol 4, chap 156