Clinical and pathological characteristics of patients with double expressor diffuse large B-cell lymphomas (DLBCLs) not otherwise specified (NOS), diagnosed at Hospital San José de Bogotá, Colombia

Abstract

Introduction: diffuse large B-cell lymphoma (DLBCL) not otherwise specified (NOS) with MYC and BCL2 overexpression by immunohistochemistry constitutes the double expressor group, which has been associated with worse outcomes compared to non-double expressor DLBCL. There is limited research on the clinical behavior of double expressor DLBCL NOS in the region. Objectives: to determine the clinical and pathological characteristics, as well as response rates, in patients diagnosed with double expressor DLBCL NOS at Hospital de San José in Bogotá. Methods: observational retrospective cohort study including patients with DLBCL NOS diagnosed at Hospital de San José between 2016 and 2019. Central pathology review was performed to confirm the diagnosis, assess cellular morphology, and evaluate MYC and BCL2 expression. Results: A total of 67 patients with DLBCL NOS were included. 49.3% of the cases originated from the germinal center and 33 cases were classified as double expressor (49.2%). The overall response rate was 42.4% in the double expressor DLBCL NOS group and 76.9% in the total DLBCL NOS population. Conclusion: Double expressor diffuse large B-cell lymphoma showed lower overall response rates following standard immunochemotherapy. High-risk International Prognostic Index (IPI) was associated with lower rates of complete response.

Keywords

• immunohistochemistry
• lymphoma large b-cell diffuse
• lymphoma non-hodgkin
• hystology
• rituximab