Malignant Histiocytic and Dendritic Cell Neoplasm

**Semantic type:** Neoplastic Process

**Definition:** A hematopoietic and lymphoid tissue neoplasm that arises from histiocytic and dendritic cells and is characterized by malignant cytological and architectural features, and presence of invasive features or metastatic potential. This category includes histiocytic sarcoma, fibroblastic reticular cell sarcoma, follicular dendritic cell sarcoma, interdigitating dendritic cell sarcoma, Langerhans cell sarcoma, and plasmacytoid dendritic cell neoplasm.