An immunohistochemical study of double-expressor lymphomas and its correlation with cell of origin.

Background: Diffuse large B cell Lymphomas (DLBCL) that co express C MYC and BCL 2 are known as 'double expressor lymphomas' and are believed to have a worse prognosis than other diffuse large B cell lymphomas. This was a study to assess the frequency of double expressor lymphomas in our cohort of DLBCL. Aims and Objectives: The aims of this study were to assess the frequency of double expression of C MYC and BCL 2 in cases of DLBCL and to correlate the same with clinicopathological parameters including cell of origin, namely germinal centre type versus non germinal centre type. Materials and Methods: This was a retrospective observational study Immunostaining for MYC antibody and BCL2 were performed using the standard polymer/DAB technique. 40% for MYC and 50% for BCL2 were taken as cut off values. Chi square analysis was used to compare the variables, and a p value of less than 0.05 was taken as statistically significant. Results: Of 40 cases studied, 11 (27.5%) were double expressors. There was no significant correlation of double expression with gender, site (nodal versus extra nodal), cell of origin namely germinal centre/non germinal centre types and Ki67 index when compared to the other group which did not show double expression. Conclusions: Immunohistochemistry is a useful technique to detect double expressor lymphomas which are known to have an aggressive course. Cell of origin did not show significant correlation with double expression in our study. [ABSTRACT FROM AUTHOR]