Editing Germ Cell Tumours (section)

====== 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.
* '''<span style="color:#ff0000">Management</span>'''
** '''<span style="color:#ff0000">If serum tumour markers elevated after induction chemotherapy, in general patients should receive salvage chemotherapy</span>'''
** ''''<span style="color:#ff0000">If serum tumour markers normal and</span>'''
*** ''''<span style="color:#ff0000">Residual mass >1 cm: resection of residual mass</span>'''
*** ''''<span style="color:#ff0000">Residual mass <1 cm: controversial management</span>'''
** If the mass was retroperitoneal, a full bilateral template RPLND should be performed.
** '''<span style="color:#ff0000">PC-RPLND in NSGCT</span>'''
*** '''<span style="color:#ff0000">Distribution of histology[https://pubmed.ncbi.nlm.nih.gov/2478726/]</span>:'''
***# '''<span style="color:#ff0000">Necrosis/fibrosis (≈40%)</span>'''
***# '''<span style="color:#ff0000">Teratoma (≈45%)</span>'''
***# '''<span style="color:#ff0000">Viable (≈15%) malignancy (with or without teratoma)</span>'''
***#* ≈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
*** '''<span style="color:#ff0000">If PC-RPLND pathology demonstrates</span>''' (2021 NCCN TEST-12)
**** '''<span style="color:#ff0000">Teratoma or necrosis/fibrosis: surveillance</span>'''
**** '''<span style="color:#ff0000">Viable disease (e.g. residual embryonal carcinoma, yolk sac, choriocarcinoma, seminoma) in PC-RPLND pathology: 2 cycles chemotherapy</span>''' (EP (etoposide/ciplatin), TIP (paclitaxel, ifosfamide, cisplatin), VIP (etoposide, ifosfamide, cisplatin), or VeIP (vinblastine, ifosfamide, cisplatin) [2021 NCCN Guidelines]
* '''<span style="color:#ff0000">FDG-PET has NO role in the assessment of patients with NSGCT and residual masses after chemotherapy</span>'''
* '''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.''' Therefore, if no disease in retroperitoneum, unlikely to have any disease elsewhere.
*** 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.