Peripheral T cell lymphoma, NOS, with hodgkin reed-sternberg-like cells: a diagnostic dilemma

Abstract

A diagnosis of peripheral T cell lymphoma (PTCL), not otherwise specified (NOS), on tissue samples is made after excluding specific types of PTCL. Although uncommon, PTCL, NOS can be associated with Hodgkin Reed-Sternberg (HRS)-like cells which can result in a misdiagnosis of classical Hodgkin lymphoma. While the HRS-like cells may be part of a reactive B cell population infected by Epstein-Barr virus (EBV)inPTCL, composite lymphoma comprising PTCL, NOS and classical Hodgkin lymphoma has been described. The ability to separate markedly reactive EBV infected B cells in the setting of a PTCL and a composite lymphoma with T cell and classical Hodgkin lymphoma can be exceedingly difficult. In this report, we detail an instance of PTCL with HRS-like cells affecting a 56-year-old Chinese female who presented with left inguinal lym-phadenopathy associated with constitutional symptoms for the previous month. The lymph node disclosed effacement by a neo-plastic T cell population, with loss of CD5 and CD7 expression in association with HRS-like cells disclosing atypical mitotic forms. The criteria for separating a composite lymphoma and a PTCL with reactive HRS-like cells, and problematic issues in achieving a correct diagnosis, are presented.