부산대학교 도서관

In the lymph node, at least four types of stromal cell subpopulations have been identified, including follicular dendritic cells, interdigitating reticular cells, indeterminate dendritic cells, and FRCs.1 Fibroblastic reticular cell tumors are dendritic cell tumors that arise from, or exhibit differentiation similar to FRCs, are the rarest subtype of dendritic cell tumors, and were unidentified until a published report in 1998.2 Since then, several cases of cytokeratin-positive interstitial reticulum cell sarcoma/tumor (CPIRCT), thought to arise from cytokeratin-positive interstitial reticulum cells, a subtype of FRCs, have been reported.3 Electron micrographs of CPIRCTs have revealed desmosome-like cell adhesion, supporting the fact that the tumor was derived from reticular tissue.4 Herein, we report the first case of CPIRCT in the skull bone, with noncaseating granuloma in intra-abdominal lymph nodes. The differential diagnosis in the present case included other types of fibroblastic and reticular cell tumors, poorly differentiated carcinoma, poorly differentiated sarcoma, bone tumors expressing epithelial markers, sarcoidosis-related lesions, and inflammation, because tumor cells did not exhibit specific differentiation and cell atypia was weak. Biopsy of the left temporal bone tumor 2 years prior to death showed spindle- to oval-shaped tumor cells in the fibrous stroma with infiltration of few lymphocytes (Figure S2a,b). [Extracted from the article]