Bcl-2 expression is associated with improved prognosis in patients with distal colorectal adenocarcinomas

Several recent studies have suggested that the anatomic location of the tum or and ethnicity of the patient should be considered in the evaluation of p rognostic markers of colorectal neoplasia, The phenotypic expression of Bcl -2 has been reported to be a useful prognostic marker in colorectal adenoca rcinoma (CRC). However, its prognostic importance in CRCs based on their an atomic location and on the ethnicity of the patients has not been reported. Therefore, we evaluated Bcl-2 expression by immunohistochemistry in CRCs c ollected from 107 African-American and 149 Caucasian patients from a southe rn U.S. population. In univariate Kaplan Meier survival analyses, Bcl-2 exp ression was associated with better overall survival of both African-America n (log-rank, p = 0.040) and Caucasian (log-rank, p = 0.032) patients with d istal but not with proximal CRCs. In multivariate Cox regression analyses, when the pathologic features of tumors were not included, the expression of Bcl-2 was associated with better survival in either ethnic patient populat ions with distal CRCs after adjusting for other confounding variables and p 53(nac) status; however, it was not significant in either race when tumor s tage was included in multivariate analyses. Thus, these studies suggest tha t the expression of Bcl-2 in CRCs is a valuable indicator of good prognosis in either race when CRCs are located in the distal colorectum. Also, these studies suggest that the expression of Bcl-2 is useful in determining prog nosis before pathologic-clinical staging and it can aid in selection of tre atment after evaluation of diagnostic biopsy specimens of patients with dis tal colorectal adenocarcinomas. (C) 2000 Wiley-Liss, Inc.