Viable Malignant Cells After Primary Chemotherapy for Disseminated Nonseminomatous Germ Cell Tumors: Prognostic Factors and Role of Postsurgery Chemotherapy—Results From an International Study Group

Abstract

PURPOSE: To assess the value of postsurgery chemotherapy in patients with disseminated nonseminomatous germ-cell tumors (NSGCTs) and viable residual disease after first-line cisplatin-based chemotherapy. PATIENTS AND METHODS: The outcome of 238 patients was reviewed. Tumor markers had normalized in all patients before resection. A multivariate analysis of survival was performed on 146 patients. RESULTS: The 5-year progression-free survival (PFS) rate was 64% and the 5-year overall survival (OS) rate was 73%. Three factors were independently associated with both PFS and OS: complete resection (P < .001), < 10% of viable malignant cells (P = .001), and a good International Germ Cell Consensus Classification (IGCCC) group (P = .01). Patients were assigned to one of three risk groups: those with no risk factors (favorable group), those with one risk factor (intermediate group), and those with two or three risk factors (poor-risk group). The 5-year OS rate was 100%, 83%, and 51%, respectively (P < .001). The 5-year PFS rate was 69% (95% confidence interval [CI], 62% to 76%) and 52% (95% CI, 40% to 64%) in postoperative chemotherapy recipients and nonrecipients, respectively (P < .001). No significant difference was detected in 5-year OS rates. After adjustment on the three prognostic factors, postoperative chemotherapy was associated with a significantly better PFS (P < .001) but not with better OS. Patients in the favorable risk group had a 100% 5-year OS, with or without postoperative chemotherapy. Postoperative chemotherapy appeared beneficial in both PFS (P < .001) and OS (P = .02) in the intermediate-risk group but was not statistically beneficial in the poor-risk group. CONCLUSION: A complete resection may be more critical than recourse to postoperative chemotherapy in the setting of postchemotherapy viable malignant NSGCT. Immediate postoperative chemotherapy or surveillance alone with chemotherapy at relapse may be reasonable options depending on the completeness of resection, IGCCC group, and percent of viable cells. Validation is necessary.