Waterton Kelita, Magro Cynthia M, Lipner Shari R
SUNY Downstate Health Sciences University College of Medicine, Brooklyn, NY, USA.
Department of Pathology and Laboratory Medicine, Weill Cornell Medicine, New York, NY, USA.
Skin Appendage Disord. 2023 Aug;9(4):284-290. doi: 10.1159/000529906. Epub 2023 Apr 14.
Onycholemmal carcinoma (OC) is a rare subtype of squamous cell carcinoma (SCC) that originates from the epithelium of the nail bed. It is characterized by distinct histopathologic features including small clusters of atypical squamous epithelium devoid of a granular layer, with abrupt onycholemmal keratinization.
We present a case of a 75-year-old male with right thumbnail onycholysis, yellow-green nail plate discoloration, as well as bleeding and purulence of the lateral nail fold. Histopathologic evaluation revealed high-grade squamous dysplasia, small clusters of severely atypical epithelial cells, and a pattern of abrupt keratinization consistent with the diagnosis of SCC carcinoma with onycholemmal features. GMS and PAS staining indicated concomitant onychomycosis. Pathologic analysis also disclosed residual SCC and concomitant amyloidosis, possibly light chain related and hence reflective of his underlying multi-organ lymphoplasmacytic lymphoma. The patient subsequently underwent Mohs micrographic surgery.
Clinical presentation of nail unit SCC with onycholemmal features is highly variable, making differentiating between similarly presenting benign and malignant nail disorders particularly challenging. This case report demonstrates clinical and histopathological features of nail unit SCC with onycholemmal features to improve diagnosis and management.
甲床癌（OC）是一种罕见的鳞状细胞癌（SCC）亚型，起源于甲床上皮。其特征为独特的组织病理学特征，包括缺乏颗粒层的小簇非典型鳞状上皮，伴有突然的甲床角化。
我们报告一例75岁男性患者，右拇指出现甲剥离、甲板黄绿变色，以及甲褶外侧出血和化脓。组织病理学评估显示高级别鳞状上皮发育异常、小簇严重非典型上皮细胞，以及与具有甲床特征的鳞状细胞癌诊断一致的突然角化模式。GMS和PAS染色显示合并甲癣。病理分析还发现残留的鳞状细胞癌和合并的淀粉样变性，可能与轻链相关，因此反映了其潜在的多器官淋巴浆细胞性淋巴瘤。该患者随后接受了莫氏显微外科手术。
具有甲床特征的甲单位鳞状细胞癌的临床表现高度多变，使得区分表现相似的良性和恶性甲病特别具有挑战性。本病例报告展示了具有甲床特征的甲单位鳞状细胞癌的临床和组织病理学特征，以改善诊断和管理。
