DNA ploidy in oral cavity carcinomas, with special reference to prognosis

Single-cell DNA cytofluorometry was performed on paraffin-em bedded tissue of 140 patients with squamous cell carcinomas of the oral cavity. Half of the tumors (71 of 140) were DNA nondip loid. Well-differentiated carcinomas were more often DNA dip loid than moderately well-differentiated ones (P<0.001; chi square). The aneuploid tumors responded better to preoperative radiotherapy than did the DNA diploid (P<0.001) and polyploid tumors (P<0.05; chi-square). Using the multivariate Cox's re gression analysis multiploid type tumor, age of the patients and presence of lymph node metastases were the only significant factors influencing survival. DNA diploid tumors in stages I and II had a better prognosis than DNA nondiploid (P<0.01; Kaplan-Meier). The reverse was true for stages III and IV, where DNA nondiploid tumors had a better prognosis (P<0.05; Kaplan-Meier). Tumor stages (P<0.001; Kaplan-Meier) and especially lymph node metastases (P<0.0005; Kaplan-Meier) were major prognostic factors. Tumor DNA ploidy may be a complement to clinical and morphologic parameters as a prognostic predictor in squamous cell carcinoma of the oral cavity.