A case of Langerhans' cell histiocytosis associated with Hodgkin's lymphoma: Fine‐needle aspiration cytologic and histopathological features

Langerhans cell histiocytosis (LCH) can be associated with a variety of malignant neoplasms, the most common being malignant lymphoma, especially Hodgkin's lymphoma (HL). In this report, we describe the fine needle aspiration (FNA) cytologic features of a case with concurrent LCH and HL in a lymph node. A 20‐year‐old man presented with an enlarged left upper cervical lymph node. FNA smears from the swelling revealed numerous CD1a+ and S‐100+ Langerhans‐type cells (LCs) along with many eosinophils, neutrophils, and lymphocytes; there were also large atypical cells with enlarged nuclei having prominent nucleoli. The cytodiagnosis was LCH and the possibility of association with or trans‐differentiation into a lymphoma was suggested. The histopathological diagnosis of the excised left cervical lymph node was classical HL‐nodular sclerosis type (CHL‐NS) with LCH. The lacunar type Reed‐Sternberg (RS) cells were positive for CD30 and CD15, and the LCs were positive for CD1a and S‐100 protein. PET/CT imaging demonstrated hypermetabolic lymph nodes in neck, abdomen, thorax and pelvis as well as pulmonary nodules and a splenic mass. The patient received 13 courses of chemotherapy and two years later, the enhanced CT revealed regressive course of the disease. Diagn. Cytopathol. 2016;44:128–132. © 2015 Wiley Periodicals, Inc.