[Expression of proto-oncogene bcl-2 in squamous cell carcinoma of the larynx].

: Apoptosis, or programmed cell death, is responsible for deleting cells in normal tissues to maintain homeostasis after DNA damage. Apoptosis has several physiological inhibitors, one of the most important being the proto-oncogene bcl-2. An immunohistochemical study was made of bcl-2 expression in 25 squamous cell carcinomas of the larynx, in laryngeal mucosa distant from the primary neoplasm, and in lymph node metastases. The relationship between bcl-2 expression and various clinical and pathological parameters was investigated. Bcl-2 was detected in 40% of primary tumors and in 71% of lymph node metastases; it seems to be a late event in laryngeal malignant transformation. We found no statistical association between bcl-2 expression and most of the clinical and pathological parameters examined. Only tumor differentiation was related to bcl-2 expression, bcl-2 positive tumors being moderately or poorly differentiated (p < 0.02).