Epstein-Barr virus-associated Inflammatory Pseudotumor-like Follicular Dendritic Cell Tumor in the Spleen of a Patient with Diffuse Large B Cell Lymphoma: A Case Report and Review of the Literature

ABSTRACT

We report a case of an Epstein-Barr virus (EBV)-associated inflammatory pseudotumor-like follicular dendritic cell tumor (IPT-like FDC tumor). The tumor occurred in the spleen of a 64-year-old woman with a history of a diffuse large B-cell lymphoma (DLBCL) of neck nodes that presented four years ago. The splenectomy specimen revealed a 5 cm-sized, tan-colored and well-circumscribed mass. Histologically, spindle or ovoid cells with large vesicular nuclei were admixed with abundant inflammatory cells. Immunohistochemically, spindle cells were positive for FDC marker CD35, but negative for CD20, CD30 and ALK. EBV was detected almost exclusively in spindle cells by EBER in situ hybridization. IPT-like FDC tumors are rare, and are recognized as a distinctive clinicopathologic variant of FDC tumors. Among only 18 similar cases reported in the English language literature, the present case is the first case of a patient with a history of DLBCL.