Postchemotherapy orchiectomy in metastatic testicular germ cell tumors: Pathologic findings and predictors of residual viable disease.

OBJECTIVES

To characterize postchemotherapy (PC) orchiectomy pathology and identify clinical factors associated with residual viable disease in patients with testicular germ cell tumors (TGCT) who undergo deferred orchiectomy after upfront chemotherapy for high-volume or site-critical metastases.

MATERIALS AND

METHODS

We retrospectively reviewed patients with metastatic TGCT who underwent PC orchiectomy at Princess Margaret Cancer Centre between 1992 and 2025. Clinical, ultrasound, and pathologic features were compared between patients with benign vs. viable testicular pathology. Relapse-free survival (RFS) and cancer-specific survival (CSS) were estimated using Kaplan-Meier methods, and logistic regression was used to identify predictors of residual viable disease.

RESULTS

Eighty-two patients underwent PC orchiectomy, with a median follow-up of 3.7 years. Teratoma was present in 36 patients (44%), germ cell neoplasia in situ in 4 patients (4.9%), and seminoma in 2 patients (2.4%). At five years, RFS and CSS were 92.2% and 94.5% for patients with benign pathology, compared to 64.9% and 81.6% for those with viable disease (teratoma and/or invasive germ cell tumor [iGCT]) (P < 0.001 and P = 0.089, respectively). Predictors of viable disease included younger age, palpable testicular mass, poor-risk IGCCCG classification, receipt of second-line chemotherapy, and adverse PC ultrasound features (vascularity and/or coarse calcifications). No viable iGCT was found in patients with PC ultrasound demonstrating normal, "burnt-out" findings, or residual testicular masses < 1 cm.

CONCLUSIONS

In selected patients, residual viable iGCT following chemotherapy was uncommon, although nonbenign pathology remained frequent. While some patients demonstrated favorable postchemotherapy testicular pathology, reliable tools to distinguish benign pathology, teratoma, and viable iGCT remain limited. Accordingly, testis-preserving strategies should be considered cautiously within carefully selected clinical contexts, and their safety and effectiveness require further evaluation through prospective or multi-institutional studies.