Composite lymphoma: EBV-positive classic Hodgkin lymphoma and peripheral T-cell lymphoma: a case report

Composite lymphomas are rare and defined as hematopoietic neoplasms with more than 1 malignant lymphomatous clone showing different phenotypic features. Of all possible combinations between non-Hodgkin lymphomas, B cell or T cell, and Hodgkin lymphoma, the least frequent are the ones combining T-cell non-Hodgkin lymphoma and classic Hodgkin lymphoma. We report a case of a 55-year-old woman with cervical and mediastinal lymphadenopathy, fever, weight loss, and night sweats. A cervical lymph node biopsy revealed a composite lymphoma with classic Hodgkin lymphoma and peripheral T-cell lymphoma components. The bone marrow was not involved. The patient refused treatment and died of disease progression 2 months after diagnosis. The biopsied lymph node showed 2 distinct populations, one composed of large cells including typical Reed-Sternberg cells and their variants, with expression of CD30, CD15, PAX5, and LMP-1. The other component was more abundant and comprised polymorphic medium-sized cells with convoluted nuclei; CD3, CD5, CD2, and CD4 expression; and negativity for CD30, cytotoxic granules, and B-cell markers. Epstein-Barr virus DNA of subtype A was identified only in the Hodgkin cells. Clonal T-cell receptor gamma and beta gene rearrangements were detected in the T-cell component, whereas monoclonal immunoglobulin H gene rearrangement was found in the Hodgkin cells.