Angiomyoma presenting as a painful subcutaneous mass: a diagnostic challenge

Abstract

Angiomyoma of the extremity is a notoriously elusive preoperative diagnosis, as the list of differentials for its described classic clinical features of a painful mobile subcutaneous mass is quite vast. Imaging features described for angiomyomas are far from being specific. On ultrasound, angiomyomas are mostly described as a well-defined solid mass lesion showing robust internal vascularity. On T2-weighted MRI they have been described as homogenous to heterogeneously hyperintense relative to skeletal muscle. We report a pathologically proven angiomyoma around the knee joint in a middle aged man, describe its clinical and imaging features, and outlay an approach in diagnosing this rare entity as a differential for painful subcutaneous mass lesions.

Angioleiomyoma of the Extremities: Findings on Ultrasonography and Magnetic Resonance Imaging

“…Interestingly, 4 (50%) of the 8 cases in which contrast‐enhanced images were available showed enhancing structures on one or both ends of the mass. Although Yoo et al described enhancing tubular structures adjacent to the mass in most cases (7 of 8 cases) and Kumar et al described an enhanced small vessel converging at the superior pole of the mass, a detailed description and correlation with another imaging modality were not reported. When we correlated the enhancing structures on MRI with the hypoechoic protrusions observed on US in this study, the enhancing structures likely represented the vessels from which the tumor arose.…”

Clinical and Sonographic Evaluation of a Lower Extremity Angioleiomyoma in a 52-Year-Old Woman

“…The differential diagnosis for a painful, subcutaneous soft tissue mass of the lower extremity is wide, including benign lesions such as neuroma, angiolipoma, and ganglia, as well as malignant conditions such as malignant leiomyosarcoma, malignant fibrous histiocytoma, and synovial sarcoma. 13,14 The typical sonographic appearance of angioleiomyoma is a hypoechoic, homogenous mass with well-defined margins, suggestive of a benign lesion. 1 Varying patterns of vascularity may be seen with angioleiomyoma as described previously.…”

Acral Calcified Angioleiomyoma Along with Radiological Features

“…Regarding the magnetic resonance imaging features, some reports described that the MRI appearances of ALM have been observed as a well-circumscribed mass with an isointense or slightly high signal intensity relative to the muscle on T1-weighted images and a heterogeneous and high signal intensity on T2-weighted and short tau inversion recovery (STIR) images [25,26]. Kumar et al [27] mentioned that diffuse homogeneous enhancement of the mass lesion with a vessel converging on the superior pole of the mass lesion was shown on postcontrast fat suppressed T1-weighted images. Kang et al [28] described that slightly high signal intensity on T1-weighted image, a heterogeneous and high signal intensity on T2-weighted and STIR images, and heterogeneous enhancement on enhanced T1weighted image were shown.…”