Background: After chemotherapy for nonseminomatous testicular germ cell tumor (NSTGCT), residual masses or recurrent disease may contain a non-germ cell malignancy (NGCM).
Methods: Over 20 years, 369 patients with disseminated NSTGCT were treated with cisplatin-based polychemotherapy at the University Medical Center Groningen. Residual tumor masses were resected in 244 patients and recurrent tumor masses in 37 patients. Histology was reviewed, focusing on the presence of NGCM.
Results: Nine patients developed an NGCM. Four patients had an NGCM in the resected residual tumor mass after chemotherapy: three patients had a sarcoma, and one patient had both a sarcoma and an adenocarcinoma. Five patients developed a late recurrence with an NGCM after 39, 40, 72, 72, and 84 months. One patient had a primitive neuroectodermal tumor, one had a sarcoma, and three had an adenocarcinoma in the resected recurrent tumor mass. A complete surgical resection was achieved in five (56%) of the nine patients. After a median follow-up of 48 months (range, 3-271 months), five patients had no evidence of disease (56%), three patients were dead of disease (33%), and one patient was alive with disease (11%).
Conclusions: Sarcoma, adenocarcinoma, or both in residual or recurrent tumor masses after combined-modality NSTGCT treatment are rare. Complete surgical resection of the tumor mass is the only curative treatment option.