Prognostic significance of histologic classification and grading of epithelial malignancies of the ovary.

Overall survival in 1938 women with epithelial ovarian cancer receiving primary treatment at Mayo Clinic was 35% at 5 years, 28% at 10 years, and 15% at 25 years. For most histologic cell types, observed differences in survival were more apparent than real since the behavior of different cell types was similar when compared stage for stage and grade for grade. Mucinous cystadenocarcinomas tended to be low grade and low stage, while serous cystadenocarcinomas tended to be high grade and high stage. For Stage I disease, factors other than cell type seemed to be more important in determining survival; specifically, Stage IA1 patients did significantly better than all other Stage I patients. In Stage III disease, the amount of residual tumor made a significant difference in survival for all grades. In Stage IV disease, the amount of residual made a highly significant difference in survival for grade 1 disease.