Rates of Teratoma and Viable Cancer at Post-Chemotherapy Retroperitoneal Lymph Node Dissection after Induction Chemotherapy for Good Risk Nonseminomatous Germ Cell Tumors

Purpose: Patients with good risk nonseminomatous germ cell tumors received induction chemotherapy with 4 cycles of etoposide and cisplatin (EPx4) or 3 cycles of bleomycin, etoposide and cisplatin (BEPx3). We report the histological results at post-chemotherapy retroperitoneal lymph node dissection after induction chemotherapy in patients treated with etoposide and cisplatin or bleomycin, etoposide and cisplatin for good risk nonseminomatous germ cell tumors. Materials and Methods: Post-chemotherapy retroperitoneal lymph node dissection was performed in 579 patients after induction chemotherapy. Of these patients 505 were treated with EPx4 and 74 were treated with BEPx3 or BEPx4. Clinical and pathological features are reported. Results: No difference in the frequency of viable residual cancer was observed with bleomycin, etoposide and cisplatin vs etoposide and cisplatin (5% vs 6%, respectively, p=not significant). Teratoma was more prevalent in the bleomycin, etoposide and cisplatin group vs etoposide and cisplatin group (57% vs 34%, respectively, p < 0.001). On multivariate analysis patients who received induction bleomycin, etoposide and cisplatin had a twofold greater risk of harboring teratoma at post-chemotherapy retroperitoneal lymph node dissection (OR 2.0; 95% CI 1.0, 4.0; p=0.04). When excluding patients from analysis who received BEPx4, those who received BEPx3 still had a 3.7-fold increased risk of teratoma in the retroperitoneum (OR 3.7; 95% CI 1.5, 8.9; p=0.004). Relapse-free and disease specific survival was not different between the 2 regimens. Conclusions: Viable cancer was equally uncommon after treatment with both regimens. Overall, relapse-free and disease specific survival did not differ between the groups. The discrepancy between regimens in the frequency of teratoma is not explained but may be due to an unrecognized selection bias rather than an effect of the regimen.