Cha Jang Gyu, Lee Young Koo, Kim Hee Kyung
Department of Orthopedics, Soonchunhyang University Bucheon Hospital, Wonmi-Gu, Bucheon-Si, Gyeonggi-Do, Korea
Orthopedics. 2012 Oct;35(10):e1562-5. doi: 10.3928/01477447-20120919-31.
Pilomatricoma, also known as calcifying epithelioma of Malherbe, is an asymptomatic, slow-growing, benign dermal neoplasm that originates from hair cortex cells. The most common sites are the head and neck (68.2%), followed by the trunk (14.4%) and the upper (15.3%) and lower (2%) extremities. The majority (60%-70%) of tumors develop in the first 2 decades of life. A typical pilomatricoma presents as a firm, calcified, dermal nodule appearing as a solid mass in subcutaneous tissue on computed tomography or magnetic resonance imaging.This article describes the case of a 42-year-old man who presented with nontender soft tissue swelling in the right ankle joint. Radiographs and magnetic resonance imaging findings showed an inflamed cystic mass with calcification in the lateral malleolar area of the right ankle joint. These atypical magnetic resonance imaging features around the ankle joint led to confusion with other disease entities, including chronic bursitis, pigmented villonodular synovitis, rheumatoid nodules, and gout. After complete excision of the mass, histological examination revealed a cystic pilomatricoma.Although rare, a cystic pilomatricoma should be considered in the differential diagnosis of soft tissue masses with calcification.
毛母质瘤，也称为马尔赫布钙化上皮瘤，是一种无症状、生长缓慢的良性皮肤肿瘤，起源于毛皮质细胞。最常见的部位是头颈部（68.2%），其次是躯干（14.4%）以及上肢（15.3%）和下肢（2%）。大多数肿瘤（60%-70%）在生命的前20年出现。典型的毛母质瘤表现为一个坚硬、钙化的皮肤结节，在计算机断层扫描或磁共振成像中显示为皮下组织中的实性肿块。本文描述了一名42岁男性患者，其右踝关节出现无痛性软组织肿胀。X线片和磁共振成像结果显示右踝关节外侧踝区有一个伴有钙化的炎性囊性肿块。踝关节周围这些不典型的磁共振成像特征导致与其他疾病实体混淆，包括慢性滑囊炎、色素沉着绒毛结节性滑膜炎、类风湿结节和痛风。肿块完全切除后，组织学检查显示为囊性毛母质瘤。虽然罕见，但在鉴别诊断伴有钙化的软组织肿块时应考虑囊性毛母质瘤。
