ObjectiveThe study was designed to compare the prognostic ability of DNA aneuploidy and S phase % by flow cytometry to that of tumor size and stage to assess prognosis in granulosa cell tumors of the ovary.Study DesignA chart review of 21 patients treated for granulosa cell tumors collected data on age, FIGO stage at diagnosis, tumor size, presence of disease, treatment, and survival. Available archival specimens were prepared for flow cytometry by a modified Hedley method. By obtaining DNA histograms and calculation of DNA index, ploidy and S phase % were assigned. Prognostic indicators were then statistically compared to survival.ResultsEarly stage rumors (I and II) were associated with relatively better disease-free survival. Tumor size > 10 cm did not indicate a poor prognosis. Of 12 adequate flow cytometry cases, aneuploidy and S phase % elevation were equal between disease-free and persistent or progressive disease groups.ConclusionEarly stage granulosa cell tumors have an excellent 5-year survival. However, other indicators to predict late recurrence are unproven. Large prospective trials with long-term follow-up are needed before flow cytometry can be adequately evaluated as a prognostic indicator for this neoplasm.