Bcl-2 expression in preinvasive and invasive cervical lesions

To determine the correlation between bcl-2 expression and clinicopathological findings in cervical intraepithelial neoplasias (CIN I, II, III) and invasive cervical lesions, and its effect on overall survival rate.

Fifty specimens derived from 22 preinvasive and invasive cervical cancer cases up to surgical stage IIb (21 squamous cervical carcinoma and 7 adenocarcinoma cases) were preserved in paraffin blocks from primary surgery and constituted the study group. Tissues were processed and stained by immunohistochemical methods to assess the degree of bcl-2 expression.

Positive bcl-2 expression was detected in 54% (13/21) of invasive lesions, while negative in 46% of cases. In CIN's, overall bcl-2 positivity was detected in 68% of cases. Bcl-2 expression was highly relevant between low grade (CIN I) and high grade (CIN II-III) lesions (p < 0.05). As regards degree of tissue staining for bcl-2 in CIN III cases, a statistically relevant difference was detected in comparison with low-grade preinvasive lesions (p < 0.05). In invasive cervical cancer cases, patients with bcl-2 positivity had a longer survival rate. By using the Cox regression model, univariate analysis did not show any specific prognostic factor to be important for survival rate, whereas, on multivariate analysis, histopathologic subtypes (p = 0.0390) and stage of tumor (p = 0.0451) had a statistically significant impact on overall survival rate.

Bcl-2 expression, especially in preinvasive lesions, may play a role in the apoptotic process and be regarded as a marker for disease progression. In invasive cervical carcinomas, bcl-2 expression has not been shown to be effective in overall survival rates.