A Case of Disseminated Extranodal Interdigitating Dendritic Cell Sarcoma Arising from Parotid Gland

1 , 2 Interdigitating dendritic cell sarcoma (IDCS) is an extremely rare tumor derived from professional antigen presenting cell and primarily found in lymph nodes, with rarer case report about extranodal presentation of IDCS. A 71-yr-old man was admitted with progressively enlarging and painless mass in the right parotid area for 2 months. Computed tomography of the neck and chest revealed enhancing mass in right parotid gland, multiple lymphadenopathies around neck and mediastinum, and an osteolytic metastasis at thoracic spine. Morphological and immunohistochemical analysis of an excisional biopsy specimen from parotid mass were consistent with a diagnosis of IDCS. Palliative chemotherapy with 6 cycles of CHOP (cyclophosphamide, adriamycin, vincristine, and prednisolone) regimen and 2 cycles of ABVD (adriamycin, bleomycin, vinblastine, and dacarbazine) regimen plus radiotherapy on parotid mass failed in tumor reduction. We describe a rare case of disseminated extranodal IDCS arising from parotid gland.