Gerstner Saucedo Jochen, Coriat Natalia, Tamayo Yudel, Moreno Jorge, Gerstner Juan B, Cardoso Fabiano N
Diagnostic Radiology, University of Colorado Anschutz Medical Campus, Aurora, USA.
General Surgery, Clinica Imbanaco, Cali, COL.
Cureus. 2025 Aug 25;17(8):e90980. doi: 10.7759/cureus.90980. eCollection 2025 Aug.
Angioleiomyoma is an uncommon benign neoplasm originating from the smooth muscle of vascular walls, typically presenting as a painful subcutaneous mass in the lower extremities of middle-aged adults. However, atypical features such as painless growth and unusual anatomical locations can obscure the diagnosis, particularly when limited imaging modalities are used. We present the case of a 62-year-old woman with a 10-month history of right ankle discomfort and a recently enlarging, painless soft-tissue mass over the anterior aspect of the ankle. Radiographic evaluation revealed a subtle soft-tissue prominence adjacent to the first tarsometatarsal joint, without calcifications or osseous involvement. Based on the clinical presentation and radiographs, a ganglion cyst was presumed, and the patient proceeded to surgical excision at her request to relieve symptoms and avoid delays. Intraoperatively, a well-circumscribed, lobulated mass was found superficial to the anterior tibial tendon sheath. Histopathology confirmed a venous-type angioleiomyoma with classic smooth muscle and vascular features, and immunohistochemistry demonstrated strong smooth muscle actin (SMA) positivity. This case illustrates a diagnostic pitfall where reliance on clinical impression and plain radiographs alone may lead to misdiagnosis. It emphasizes the value of contrast-enhanced MRI or ultrasound for preoperative assessment of indeterminate soft-tissue lesions, even when benign pathology is suspected. To our knowledge, this is the first reported case of angioleiomyoma arising adjacent to the anterior tibial tendon insertion at the first tarsometatarsal joint, expanding the known anatomical spectrum of this rare tumor.
血管平滑肌瘤是一种罕见的良性肿瘤，起源于血管壁的平滑肌，通常表现为中年成年人下肢的疼痛性皮下肿块。然而，诸如无痛生长和不寻常的解剖位置等非典型特征可能会使诊断变得模糊，尤其是在使用有限的成像方式时。我们报告一例62岁女性病例，她有10个月的右踝不适病史，且最近在踝关节前方出现一个不断增大的无痛性软组织肿块。影像学评估显示第一跗跖关节旁有一个细微的软组织隆起，无钙化或骨质受累。根据临床表现和X线片，推测为腱鞘囊肿，患者应其要求接受手术切除以缓解症状并避免延误。术中，在胫前肌腱鞘前方发现一个边界清楚、分叶状的肿块。组织病理学证实为静脉型血管平滑肌瘤，具有典型的平滑肌和血管特征，免疫组化显示平滑肌肌动蛋白（SMA）强阳性。该病例说明了一个诊断陷阱，即仅依靠临床印象和普通X线片可能会导致误诊。它强调了对比增强MRI或超声在术前评估不确定软组织病变中的价值，即使怀疑为良性病变。据我们所知，这是首例报道的血管平滑肌瘤发生于第一跗跖关节胫前肌腱附着处附近的病例，扩展了这种罕见肿瘤已知的解剖范围。
