Hang Jen-Fan, Siddiqui Momin T, Ali Syed Z
Department of Pathology and Laboratory Medicine, Taipei Veterans General Hospital, Taipei, Taiwan.
Acta Cytol. 2017;61(2):96-102. doi: 10.1159/000468505. Epub 2017 Apr 14.
Langerhans cell histiocytosis (LCH) is an uncommon neoplasm of dendritic cells and predominantly occurs in children and young adults. The study aims to evaluate cytopathologic features and current diagnostic concepts in a large series of LCH on fine needle aspiration (FNA).
We retrospectively searched the pathology archives of The Johns Hopkins Hospital (JHH) and Emory University Hospital (EUH) to identify all FNA cases diagnosed as LCH in a period of 21 years. Cytologic material and immunohistochemical stains were reviewed.
A total of 37 LCH patients (26 from JHH and 11 from EUH) with FNA diagnoses were identified. The sites of LCH included bone in 28, soft tissue of head and neck in 6, and lymph nodes in 3. Thirty-one patients (84%) were diagnosed as LCH, 4 (11%) had a descriptive diagnosis suggesting scant cellularity with epithelioid/histiocyte-like cells and mixed inflammation, and 2 (5%) were non-diagnostic due to insufficient cellularity. Immunohistochemical stains were performed on cell block sections in 26 cases, showing 24 of 24 (100%) positive for CD1a, 22 of 23 (96%) positive for S100-protein, and 3 of 3 (100%) positive for CD68.
LCH can be accurately diagnosed in FNA based on the characteristic cytomorphology and selected immunohistochemistry. Diagnosis may be difficult in cases with scant or insufficient cellular material.
朗格汉斯细胞组织细胞增多症（LCH）是一种罕见的树突状细胞肿瘤，主要发生于儿童和青年。本研究旨在评估大量细针穿刺抽吸（FNA）的LCH病例的细胞病理学特征和当前诊断概念。
我们回顾性检索了约翰霍普金斯医院（JHH）和埃默里大学医院（EUH）的病理档案，以确定21年间所有诊断为LCH的FNA病例。对细胞学材料和免疫组织化学染色进行了复查。
共鉴定出37例经FNA诊断为LCH的患者（26例来自JHH，11例来自EUH）。LCH的发病部位包括28例骨骼、6例头颈部软组织和3例淋巴结。31例（84%）被诊断为LCH，4例（11%）有描述性诊断，提示细胞数量少，伴有上皮样/组织细胞样细胞和混合性炎症，2例（5%）因细胞数量不足而无法诊断。对26例病例的细胞块切片进行了免疫组织化学染色，结果显示24例（100%）CD1a阳性，23例中的22例（96%）S100蛋白阳性，3例中的3例（100%）CD68阳性。
基于特征性的细胞形态学和选择的免疫组织化学，FNA可以准确诊断LCH。细胞材料稀少或不足的病例可能难以诊断。
