Centre for Oncopathology, Mumbai, Maharashtra, India.
Adv Anat Pathol. 2021 Jan;28(1):21-29. doi: 10.1097/PAP.0000000000000281.
Follicular dendritic cell sarcoma (FDCS) is an intermediate-grade malignancy of follicular dendritic cells, which are derived from mesenchymal stem cells. Nodal FDCS is well-recognized. However, when it occurs at an extranodal site, it may not be recognized and is often misdiagnosed. These tumors exhibit a variable spindle to epithelioid cell morphology with a lymphocytic infiltrate and a distinct immunophenotype. The World Health Organization has classified this entity under tumors of hematopoietic and lymphoid tissue, that is, histiocytic and dendritic cell neoplasms. However, its occurrence at extranodal sites and its behavior and management more closely resemble that of a soft tissue tumor. Increased awareness about the existence of FDCS at extranodal sites may aid in the reduction of diagnostic errors. We wish to draw attention to this entity by reporting our experience of 54 cases of extranodal FDCS encountered over a period of 14 years and present a review of the literature of this underrecognized entity. We also describe the ontogeny and molecular pathogenesis of this uncommon lesion.
滤泡树突状细胞肉瘤（FDCS）是一种来源于间充质干细胞的滤泡树突细胞的中度恶性肿瘤。结内 FDCS 是公认的。然而，当它发生在结外部位时，可能不会被识别，并且经常被误诊。这些肿瘤表现出多种梭形至上皮样细胞形态，伴有淋巴细胞浸润和独特的免疫表型。世界卫生组织将该实体归类为造血和淋巴组织肿瘤，即组织细胞和树突状细胞肿瘤。然而，它在结外部位的发生以及它的行为和管理更类似于软组织肿瘤。提高对 FDCS 在结外部位存在的认识可能有助于减少诊断错误。我们通过报告在 14 年期间遇到的 54 例结外 FDCS 病例来引起对该实体的关注，并对这一认识不足的实体进行文献复习。我们还描述了这种罕见病变的发生和分子发病机制。
