PROGNOSTIC-SIGNIFICANCE OF CLINICAL FACTORS AND P53 EXPRESSION IN PATIENTS WITH GLOTTIC CARCINOMA TREATED WITH RADIATION-THERAPY

BACKGROUND. Numerous clinical parameters have been suggested as predic tors of outcome for patients with head and neck carcinoma treated with radiation therapy, but their applicability remains controversial. Ina ctivation of the p53 tumor suppressor results in radioresistance in ex perimental systems and might predict treatment failure in human patien ts. We have tested this hypothesis by comparing the predictive power o f nuclear accumulation of p53 protein with that of clinical and histop athologic markers in patients with glottic carcinoma treated with prim ary radiotherapy. METHODS. Clinical charts were reviewed for 165 patie nts with glottic squamous cell carcinoma treated with radiation therap y. One hundred and twenty-one patients with T1 or T2 classified tumors were determined to have received adequate treatment and to have adequ ate follow-up data for further study. Archival pretreatment tumor biop sies from a subpopulation of patients were examined for p53 protein by immunohistochemistry. The influence of clinical and histopathologic v ariables and p53 nuclear protein on tumor recurrence was studied by bi variate and multivariate analysis. RESULTS. The recurrence rate was lo west for patients with moderately to poorly differentiated tumors (P < 0.05). This was the only significant predictor of outcome in this pat ient population. The presence of immunohistochemically detectable p53 antigen was not predictive of tumor recurrence in 70 patients for whom there was both p53 and sufficient follow-up data. CONCLUSIONS. Histol ogic differentiation was prognostic for tumor recurrence in this popul ation of patients with glottic carcinoma treated with radiation therap y. In contrast, nuclear accumulation of p53 protein was not predictive of tumor response or recurrence in this population. (C) 1996 American Cancer Society.