COMPARISON OF DNA PLOIDY AND S-PHASE FRACTION WITH PROGNOSTIC FACTORS IN GASTRIC CANCER

OBJECTIVE: To assess the value of DNA ploidy and S-phase fraction (SPF) as prognostic factors in gastric cancer. STUDY DESIGN: DNA ploidy and SPF were analyzed in 289 gastric cancer cases using flow cytometry and compared with the clinical and histopathologic features of the tumors. RESULTS: Aneuploidy was found in 36% of the patients; it was more frequent in the intestinal type of cancer (56%) as compared to the diffuse type (15%). Aneuploidy was also related to advanced TNM stage, cardiac location and high mitotic activity. In univariate survival analysis, TNM stage and tumor size were the most important prognostic factors. High SPF was significantly related to inferior survival rates, but DNA ploidy did not have any significant correlation with survival when all patients were analyzed together. However, in diffuse-type cancer, both DNA ploidy and SPF were significant prognostic factors. In multivariate analysis, DNA ploidy proved to be an independent predictor of survival in gastric cancer. CONCLUSION: The results indicate that in addition to TNM stage, flow cytometric analysis of DNA ploidy and SPF are important prognostic factors in gastric cancer.