Abstract
Interdigitating dendritic cell sarcoma (IDCS) is an extremely rare neoplasm derived from a type of dendritic cells. We experienced treating a case of IDCS involving the skin and probably bone marrow. Histopathological examination of the involved skin lesion revealed a massive invasion of large atypical lymphoid cells. Immunohistochemically, the neoplastic cells were positive for S100 and CD68, and negative for CD1a, CD21, and CD23. These findings led to the diagnosis of IDCS. Although a bone marrow biopsy showed unremarkable findings, a small number of neoplastic cells were observed in a bone marrow smear. Because the skin lesions were extensive and bone marrow infiltration was suspected, the patient was administered ABVD therapy.
