RESUMO
Identification of molecular events of the recurrent squamous cell carcinoma [SCC] of the larynx and pharynx may aid in refining treatment strategies and improving outcome. The underlying molecular events of these recurrent tumours involves alterations in the tumor suppressor genes [p53] and protooncogenes [Bc1-2]. We hypothesize that the development of these recurrent tumours involves alterations of the p53 and Bcl-2 proteins. To test this hypothesis, 15 laryngeal and pharyngeal biopsy specimens obtained from 15 patients with recurrent laryngeal or pharyngeal squamous cell carcinoma with different grades [II-IV] were immunostained for p53 and Bcl-2 protein expression. Examination of the percentage of positive cells in the normal mucosa and SCC, respectively, showed significant upregulation of p53 [0.0 +/- 0.0 Vs. 51.8 +/- 5.9; p= 0.00] and Bcl-2 protein expression [36.5 +/- 3.5 vs. 74.6 +/- 1.9; p= 0.00]. Alterations of the p53 and Bcl-2 proteins occur during the development of recurrent SCC. Additional studies are needed to confirm and extend our results