Objective: The aim of this study was to investigate the clinicopathological prognostic factors of malignant ovarian germ cell tumors (MOGCT) and evaluate the survival trends of MOGCT by histotype. Methods: We extracted data on 1,963 MOGCT cases diagnosed between 2000 and 2014 from the Surveillance, Epidemiology, and End Results (SEER) database and the histological classification of MOGCT, including 5 categories: dysgerminoma, embryonal carcinoma (EC), yolk sac tumor, malignant teratoma, and mixed germ cell tumor. We examined overall and disease-specific survival of the 5 histological types. Kaplan-Meier and Cox proportional hazards regression models were used to estimate survival curves and prognostic factors. We also estimated survival curves of MOGCT according to different treatments. Results: There was a significant difference in prognosis among different histological classifications. Age, histotype, grade, SEER stage, and surgery were independent prognostic factors for survival of patients with MOGCT. For all histotypes, 1-, 3-, and 5-year survival rate estimates were >85%, except for EC, which had the worst outcomes at 1 year (55.6%), 3 years (44.4%), and 5 years (33.3%). In the distant SEER stage, both chemotherapy and surgery were associated with improved survival outcomes compared with surgery- and chemotherapy-only groups. Conclusions: Dysgerminoma patients had the most favorable outcomes, whereas EC patients had the worst survival. A young age, low grade, and surgery were all significant predictors for improved survival. In contrast, a distant SEER stage was a risk factor for poor survival. Chemotherapy combined with surgery contributed to longer survival times of patients with MOGCT in the distant SEER stage.
Generating survival times to simulate Cox proportional hazards models with time‐varying covariates