Schuerfeld K, Lazzi S, De Santi M M, Gozzetti A, Leoncini L, Pileri S A
Department of Human Pathology and Oncology, Siena University, Siena, Italy.
Histopathology. 2003 Nov;43(5):491-4. doi: 10.1046/j.1365-2559.2003.01738.x.
Tumours of dendritic/accessory cell origin are rare neoplasms arising in lymph nodes. Among these, tumours derived from cytokeratin-positive interstitial reticulum cells (CIRCs), a subset of fibroblastic reticulum cells, are reported even less frequently. The International Lymphoma Study Group (ILSG) has recently proposed a classification for tumours of histiocytes and accessory dendritic cells in which CIRC tumours are not included. We report a case of a CIRC tumour arising in a submandibular lymph node of a 66-year-old male.
The neoplasm was composed of spindle cells with elongated or round nuclei, prominent nucleoli and abundant cytoplasm. These cells were arranged in a diffuse fascicular and vaguely whorled pattern. The tumour cells stained diffusely for S100, vimentin, desmin, lysozyme, and focally for CD68 and cytokeratins 7, 8, 18, CK-AE1 and CK-pool. Electron microscopy was performed for further evaluation on samples taken from the paraffin block; this revealed cytoplasmic projections and rudimentary cell junctions.
Histopathologist should be aware of the existence of tumours deriving from CIRCs, as these cases may be misdiagnosed as metastatic carcinoma. Careful clinical and pathological evaluation is necessary to exclude this possibility.
树突状/辅助细胞起源的肿瘤是发生于淋巴结的罕见肿瘤。其中，源自细胞角蛋白阳性的间质网状细胞（CIRCs）（成纤维细胞网状细胞的一个亚群）的肿瘤报道更为少见。国际淋巴瘤研究组（ILSG）最近提出了一种组织细胞和辅助树突状细胞肿瘤的分类方法，其中未包括CIRC肿瘤。我们报告一例发生于一名66岁男性下颌下淋巴结的CIRC肿瘤。
肿瘤由具有细长或圆形核、明显核仁及丰富细胞质的梭形细胞组成。这些细胞呈弥漫性束状排列且有模糊的漩涡状结构。肿瘤细胞弥漫性表达S100、波形蛋白、结蛋白、溶菌酶，局灶性表达CD68及细胞角蛋白7、8、18、CK-AE1和细胞角蛋白池。对取自石蜡块的样本进行电子显微镜检查以进一步评估；结果显示有细胞质突起和原始细胞连接。
病理学家应意识到源自CIRCs的肿瘤的存在，因为这些病例可能被误诊为转移性癌。需要进行仔细的临床和病理评估以排除这种可能性。
