Indeterminate Dendritic Cell Tumor: A Case Report of a Rare Langerhans Cell Lineage Disease.

Abstract

Indeterminate dendritic cell tumor (IDCT) is a very rare neoplastic disorder composed of so-called indeterminate cells [1]. Although it was first described in the early 1980s [2], its pathogenesis and cellular origin have not been completely defined. These indeterminate cells morphologically and immunophenotypically resemble Langerhans cells, as they are immunopositive for S100 protein and CD1a. However, they typically lack both Birbeck granules and langerin expression [1,3]. Due to its rarity and similarity to Langerhans cell lesions (LCL), IDCT can be misdiagnosed; however, the pathobiology of IDCT is different from that of LCL. Even though the clinical behavior of IDCT has not yet been firmly established, no direct mortality due to IDCT has been reported so far [1,4]. Recently, we experienced a case of IDCT with typical histologic features. This is the first reported case of IDCT in Korea, which pathologists should include in the differential diagnosis of Langerhans cell-like lesions.