Multinational study to identify prognostic risk factors in adult patients with malignant ovarian germ cell tumors stage IC and beyond

Malignant ovarian germ cell tumors (MOGCTs) are aggressive malignancies predominantly affecting young women. A study including 254 patients with stage IC-IV MOGCT in the UK and Italy was carried out to identify relevant prognostic factors. The median age was 27 years (IQR 21-31). Initial treatment was surgery in 87.8% of patients (50.4% fertility sparing, 37.4% nonsparing) or neoadjuvant chemotherapy. Most underwent BEP or POMB/ACE chemotherapy, with 32.5% receiving high-dose chemotherapy (HDCT) at relapse. First-line treatment resulted in complete response in 84.6% and partial response or stable disease in 7.9%, while 4.7% progressed. Overall, 14.6% died of disease. Ten-year progression-free survival rate was 82.8% (95% CI 77.2-87.2) whereas ten-year cancer-specific survival (CSS) rate was 83.2% (77.3-87.7); ten-year CSS rate for stage IV disease was 79.4% (69.5-86.4). Age ≥ 35 years (HR 2.8; p=0.003), stage III/IV disease (HR 1.4; p=0.035), and nondysgerminoma histology (HR 7.3; p=0.01) were associated with worse CSS on multivariable analysis. By contrast, CSS of immature grade 2-3 MOGCT mirrored dysgerminomas. HDCT appeared to improve survival in first but not later relapses. The authors conclude that advanced stage, higher age, and nondysgerminoma (excluding grade 2/3 immature teratomas) are adverse prognostic factors in MOGCT. Stage IV disease can achieve 80% long-term survival rates.