Cell proliferation as an independent predictor of survival for patients with advanced nasopharyngeal carcinoma.

Commonly used clinical and pathologic criteria are often of limited value in predicting the outcome of patients with undifferentiated nasopharyngeal carcinoma, and new parameters related to the biology of growth of neoplastic cells are still required for better definition of the aggressiveness of these tumors. The prognostic significance of DNA ploidy, measured by image cytometry on isolated cells, and of the mitotic index, proliferating cell nuclear antigen, and p53 protein, all measured by image cytometry in histologic sections, were evaluated on archival tumor tissues from 53 patients with Stage III or IV nasopharyngeal carcinomas. Patients were staged according to the criteria of the International Union Against Cancer and were irradiated according to a conventional radiotherapy schedule. No significant associations were found between biologic parameters and clinical features. Only the stage and the mitotic index were related to patient survival, and, when examined in a proportional hazard regression analysis, both provided independent information. When patients with compromised skull and/or cranial nerves (T4 tumors), who had a very short survival, were eliminated from the analysis, only the mitotic index and proliferating cell nuclear antigen allowed discrimination of a subset of patients with poor prognoses. This study shows that the assessment of cell proliferative activity can provide useful information for better predicting the clinical course of high-risk patients with nasopharyngeal carcinomas and improve therapeutic strategies.