Flow cytometric analysis of DNA ploidy and S-phase fraction of Stage IIIB cervical carcinoma

OBJECTIVES: To evaluate the role of flow cytometry-measured DNA ploidy and S-phase fraction as survival prognostic indicators in women with FIGO Stage IIIB squamous cell carcinoma of cervix. METHODS: We retrospectively reviewed the medical and pathological records of women with Stage IIIB squamous cell cervical carcinoma treated between 1993 and 1996. Flow cytometric analysis of DNA ploidy and S-phase fraction was performed by the modified Hedley technique using paraffin-embedded tissue. Survival was calculated using the Kaplan-Meier life-table analysis. RESULTS: Of the 75 cases, 66 were analyzable. Diploid tumors were found in 73%. The mean S-phase fraction was 14% (SD = 5.4). The overall 5-year survival rate was 60%. The survival of patients with aneuploidy tumors was significantly worse than that of the diploid tumors (p = 0.001). The survival of the patients who had S-phase fraction > 12% was significantly worse than those who had S-phase fraction < or =12% (p = 0.04). CONCLUSIONS: In this homogeneous study population, we found that aneuploidy and S-phase fraction >12% correlated with poor survival. Identifying this poor prognostic group would be of benefit in considering additional treatment for a better outcome.