Composite diffuse large B-cell lymphoma and classical Hodgkin's lymphoma of the stomach: case report and literature review.

The combination of classical Hodgkin's lymphoma (cHL) and non-Hodgkin lymphoma coexisting in the same patient is not common, especially in one extranodal location. Here we present a rare case of composite diffuse large B-cell lymphoma (DLBCL) and cHL occurring simultaneously in the stomach of a 53-year-old female who presented with upper abdominal discomfort and gas pain. Surgery was performed and the disease was diagnosed pathologically as composite lymphoma of DLBCL and cHL using hematoxylin-eosin and immunohistochemical staining. Epstein-Barr virus (EBV) infection was not detected by in situ hybridization for EBV-encoded RNA or immunohistochemistry for EBV latent membrane protein-1. Polymerase chain reaction analysis from the two distinct components of the tumor demonstrated clonal immunoglobulin κ light chain gene rearrangements. The patient died approximately 11 mo after diagnosis in spite of receiving eight courses of the CHOP and two courses of the rituximab-CHOP (RCHOP) chemotherapy regimen. This case report showed that the two distinct components, DLBCL and cHL, appeared to originate from the same clonal progenitor cell, and that EBV infection was not essential for transformation during the course of tumorigenesis.