Bcl-2 expression in sequential biopsies of potentially malignant oral mucosal lesions assessed by immunocytochemistry

OBJECTIVE: To examine, for the first time Bcl-2 expression in sequential (a utogenous) oral mucosal biopsies taken from the same sites in a gender, ris k-factor matched, Caucasoid sample, over a 21-year period, DESIGN: Retrospective immunocytochemical longitudinal study of archival ser ial biopsies. MATERIALS AND METHODS: Computer records were used to identify biopsy specim ens derived from 12 patients. These were divided into four groups: (I) Hist ologically innocuous lesions which remained histologically innocuous. (2) D ysplastic lesions which remained dysplastic, (3) Histologically innocuous l esions which later progressed to squamous cell carcinoma (SCC), (4) Dysplas tic lesions which later progressed to SCC, This represented 65 biopsies in total. Bcl-2 expression was studied using mouse antihuman BCL-2 oncoprotein clone 124 (Dako, Denmark), RESULTS: Generally, there was a lack of Bcl-2 immunoreactivity in the epith elium, with one exception in dysplastic epithelium from a group (3) patient . CONCLUSION: These findings suggest that in our series, Bcl-2 is not express ed early in oral premalignant lesions and appears to contradict previous re ports. Possible explanations for this disparity are considered.