Epstein—barr virus‐containing t‐cell lymphoma presents with hemophagocytic syndrome mimicking malignant histiocytosis

Background. The previously designated malignant histiocytosis (MH) may include lymphoid neoplasms of T‐cell lineage as well as patients with benign virus‐associated hemophagocytic syndrome (VAHS). In this study, the association of Epstein‐Barr virus (EBV) with T cell lymphomas which present with clinicopathologic features indistinguishable from malignant histiocytosis (MH) was investigated further. Methods. Four adult patients, three women and one man, were admitted because of fever, cutaneous lesions, hepatosplenomegaly, and jaundice. Laboratory examinations revealed pancytopenia, abnormal liver functions, and coagulopathy. All patients ran a fulminant course terminating in a hemophagocytic syndrome within 1 month. Immunophenotypic study, Southern blot analysis, and in situ hybridization were performed on the specimens obtained from the four patients. Results. The biopsy‐necropsy specimens from skin, liver, spleen, and bone marrow showed infiltration of atypical large cells with reactive histiocytosis and florid hemophagocytosis activity. Based on the clinical and histologic findings, these cases would have been designated as MH by previous criteria. Immunophenotypic, Southern blot, and in situ hybridization studies, however, showed clonotypic proliferation of EBV genomes in the nuclei of the large atypical cells that expressed T‐cell antigens. Therefore, these patients should be diagnosed as a recently described EBV‐associated peripheral T‐cell lymphoma (EBV‐PTCL). Conclusions. EBV‐PTCL may present with a fulminant hemophagocytic syndrome indistinguishable from the previously designated MH. This finding represents a step forward in our changing concept regarding MH, some of which only recently has been suggested to be of T‐cell lymphoma origin. Differentiation from benign VAHS is clinically important. Features useful in this distinction are tabulated and discussed.