The significance of concurrent MYC and BCL2 expression in Egyptian patients with diffuse large B-cell NHL.

ABSTRACT

This study aimed to investigate the frequency of MYC/BCL2 co-expression using immunohistochemistry (IHC) in Egyptian patients with diffuse large B-cell lymphoma (DLBCL) and its impact on treatment outcomes, overall survival (OS), and disease-free survival (DFS). A total of 100 adult patients with newly diagnosed DLBCL were included in the study and treated with the R-CHOP regimen. The cases were classified into germinal center B-cell (GCB) and non-germinal center B-cell (non-GCB) subtypes based on IHC. Our results showed that a subset of the studied cases didn't achieve complete remission (CR) after chemotherapy (22%). Co-expression of MYC and BCL2 was observed in 20% of the cases, with most of them belonging to the non-GCB subtype. The CR rate was significantly lower in the double-expressor (DE) group (45%), while no significant difference was observed in CR between the GCB and non-GCB cases. The DE group was associated with advanced stage, extra-nodal involvement, and high-risk R-International Prognostic Index (R-IPI). Both the non-DE and GCB groups demonstrated better DFS, while the non-DE group only showed better OS. Both non-DE status and GCB subtype were identified as independent factors affecting DFS. In conclusion, the concurrent expression of MYC and BCL2 in DLBCL indicates an inferior outcome and lower chemotherapy response. The current chemotherapeutic strategy has not effectively improved the outcomes of this aggressive lymphoma subtype. Therefore, the identification of these patients is crucial for selecting appropriate treatment options.