Primary Cutaneous Interdigitating Dendritic Cell Sarcoma: A Case Report and Review of the Literature.

Interdigitating dendritic cell sarcoma (IDCS) is defined as a neoplastic proliferation of spindle to ovoid cells with phenotypic features similar to those of interdigitating dendritic cells, which are present in the T cell-rich areas of lymphoid organs and participate as antigen-presenting cells responsible for initiating primary T lymphocyte immune response. IDCS usually presents with lymphadenopathy. Solitary lymph node involvement is often seen. Extra nodal presentation has been described as well. Cutaneous lesions are extremely rare, and less than 10 cases have been previously documented in medical literature. Here, the authors describe another primary cutaneous IDCS in a 42-year-old patient and review the literature.