Prognostic Significance of Bcl-2 Expression in Non-germinal Center B-cell-Like Diffuse Large B-cell Lymphoma

Introduction: Diffuse large B -cell lymphomas (DLBCLs) are a group of malignant neoplasms with extensive clinical and molecular heterogeneity. Several key genetic aberrations have been identified, such as those involving the MYC , BCL6 , and BCL2 genes. Prior studies on the prognostic significance of Bcl-2 protein expression in DLBCL have been contradictory, with some suggesting it has an adverse effect, while others have shown no such association. Bcl-2 is known to be more highly expressed in the non -germinal center Bcell -like (non -GCB) subtype compared to germinal center B -cell-like (GCB) DLBCL. Non -GCB status is associated with a less favorable prognosis. This study aimed to investigate whether the expression of Bcl-2 protein in non -GCB DLBCL influences response to treatment, progression -free survival, or overall survival. Methods: In this retrospective study, we investigated whether there was a difference in the clinical outcomes of non -GCB DLBCL cases (n = 97) that were confirmed by immunochemistry to demonstrate high levels of Bcl-2 protein expression (>50% neoplastic cells stained) when compared to those who were deemed negative based on this criterion. Response to rituximab-based induction immunochemotherapy, five-year progression -free survival, and five-year overall survival were assessed. Results: There was no statistically significant difference in response to treatment, five-year progressionfree survival, or five-year overall survival between the patients who were positive for Bcl-2 (n = 70) compared to those who were considered Bcl-2 negative (n = 27). Conclusion: High levels of Bcl-2 protein expression do not appear to be of prognostic significance in nonGCB DLBCL and therefore Bcl-2 may not be a key therapeutic target in the treatment and improvement of clinical outcome in such cases.