Histologic grade in advanced ovarian cancer.

The histologic grade of epithelial ovarian tumors was found to be a major prognostic factor for survival in patients with advanced (stage III-IV) disease. In addition, a grading system based on cytologic detail (modified Broders' grades I-IV) identified groups with a differential response to chemotherapy. The overall improvement in survival observed with combination chemotherapy was related primarily to an increased survival of patients with grade II and III lesions. Although the survival of patients with grade I lesions was markedly better than for patients with grade IV lesions, in neither case was it influenced by the choice of single-agent or combination chemotherapy. In prospective clinical trials in advanced disease, modified Broders' grades should be included as a separate stratification factor.