Introduction. C-MYC is one of the essential transcription factors that play a role in various cellular functions. The MYC rearrangement is associated with low overall survival and low progression-free survival, increased risk of central nervous system disease relapse in patients diagnosed with diffuse large B cell lymphoma (DLBCL) and treated with R-CHOP. Also, c-MYC amplification is an unfavorable prognostic factor, amplified by BCL2 and BCL6 rearrangements, respectively, designating lymphomas as high grade according to the WHO 2016 revision. Objectives. We search the correlations of the double or triple expression of C-MYC and BCL2 and/or BCL6 markers, with clinical survival data. Methods. A cohort of 80 patients with DLBCL was examined for MYC, BCL2 and BCL6 immunohistochemical expression.
Results. Six, respectively four, patients of the total cohort were MYC/BCL2 and MYC/BCL6 positive and only 3 were MYC/BCL2/BCL6 triple positive. The median overall survival was 6 months, 95% confidence interval (CI)) for triple expression and 13 months (CI 95%) for MYC/BCL2, respectively MYC/BCL6 dual expression. Complete therapeutical response was registered in 2 patients with triple expression and 4, respectively 2 patients, with MYC/BCL2 and BCL6 dual expression. Relapse was registered in 1 patient, either MYC/BCl2 dual positivity respectively triple positivity, and in 2 patients with MYC/BCL6 positivity. Conclusions. Our study has showed that the double and triple positivity expression in DLBCL have a low incidence (15%) and are correlated with poor survival, the prognosis being unfavorable.
Keywords: DLBCL, MYC/BCL2/BCL6, double triple expression, survival.