Histiocytic sarcoma (HS) is a haematopoietic tumour of histiocyte origin that has been sporadically reported in four-toed hedgehogs (Atelerix albiventris). The present study aimed to investigate clinical, gross, histopathological and immunohistochemical features of HS in eight hedgehogs. Histological and immunohistochemical features of normal histiocytes and Langerhans cells (LCs) of hedgehogs were also investigated. HLA-DR-, Iba-1- and E-cadherin-positive LCs were observed in the epidermis, while Iba-1- and CD204-positive histiocytes were detected in the lymph nodes and spleen of normal hedgehogs. Localized HS (six cases) developed in the skin and spleen, while disseminated HS (two cases) occurred in the intestine. Tumour cells of disseminated HS were also distributed within the mesenteric lymph nodes, liver, kidney, spleen, lung and adrenal glands. Tumour cells of both localized and disseminated HS were composed of histiocytic cells, spindle to pleomorphic cells, multinucleated giant cells and erythrophagocytic cells. Most tumour cells were immunopositive for Iba-1, CD204 and lysozyme. A small number of tumour cells were positive for E-cadherin and CD208, and the tumour cells in one case were positive for HLA-DR. These results suggest that the tumour cells have variable features of histiocyte origin, including dendritic cells, LCs and macrophages. The behaviour of HS in the hedgehog was very aggressive, and 50% of cases died within 90 days of resection. The present study also highlighted the tendency for local tumour recurrence in localized cutaneous HS cases, suggesting a requirement for a long-term follow-up after excision.

组织细胞肉瘤（HS）是组织细胞起源的造血肿瘤，在四趾刺猬（Atelerix albiventris）。本研究旨在调查八只猬中HS的临床，总体，组织病理学和免疫组化特征。还研究了正常组织细胞和刺猬的朗格汉斯细胞（LC）的组织学和免疫组化特征。在表皮中观察到HLA-DR-，Iba-1和E-cadherin阳性LC，而在正常刺猬的淋巴结和脾脏中检测到Iba-1和CD204阳性组织细胞。皮肤和脾脏出现局部HS（6例），而肠道则出现了弥散性HS（2例）。弥漫性HS的肿瘤细胞也分布在肠系膜淋巴结，肝，肾，脾，肺和肾上腺中。局部和扩散HS的肿瘤细胞均由组织细胞，纺锤体到多形性细胞组成，多核巨细胞和红细胞吞噬细胞。大多数肿瘤细胞对Iba-1，CD204和溶菌酶呈免疫阳性。少数肿瘤细胞对E-钙粘蛋白和CD208呈阳性，其中一例肿瘤细胞对HLA-DR呈阳性。这些结果表明，肿瘤细胞具有组织细胞起源的可变特征，包括树突状细胞，LC和巨噬细胞。刺猬的HS行为非常凶猛，有50％的病例在切除90天内死亡。本研究还强调了局部皮肤HS病例中局部肿瘤复发的趋势，提示切除后需要长期随访。1例肿瘤细胞为HLA-DR阳性。这些结果表明，肿瘤细胞具有组织细胞起源的可变特征，包括树突状细胞，LC和巨噬细胞。刺猬的HS行为非常凶猛，有50％的病例在切除90天内死亡。本研究还强调了局部皮肤HS病例中局部肿瘤复发的趋势，提示切除后需要长期随访。1例肿瘤细胞为HLA-DR阳性。这些结果表明，肿瘤细胞具有组织细胞起源的可变特征，包括树突状细胞，LC和巨噬细胞。刺猬的HS行为非常凶猛，有50％的病例在切除90天内死亡。本研究还强调了局部皮肤HS病例中局部肿瘤复发的趋势，提示切除后需要长期随访。