Intramuscular Myxoma in the Vastus Medialis Muscle: A Case Report and Brief Review of the Literature.

Abstract

Introduction: Intramuscular myxomas (IMMs) are rare benign tumors of mesenchymal origin, typically occurring in middle-aged women. These tumors are characterized by hypocellular, hypovascular lesions rich in extracellular myxoid stroma. IMMs are most commonly found in the heart but rarely may affect large muscle groups such as the thighs, shoulders, and buttocks. While they are generally isolated lesions, IMMs may be associated with syndromes such as Mazabraud syndrome or McCune-Albright syndrome. Accurate diagnosis relies on imaging and histopathological evaluation, with surgical excision being the definitive treatment.

Case report: We present the case of a 25-year-old female patient who reported a noticeable dysmorphism in the inner thigh region without pain or functional impairment. Magnetic resonance imaging revealed a smooth-bordered, oval lesion in the vastus medialis muscle measuring 2.8 × 2 cm. A percutaneous biopsy confirmed the diagnosis of an IMM. Eventually, the intramuscular myxoma was surgically removed without complications.

Conclusion: Accurate imaging and histopathological confirmation remain critical for diagnosis, and a case such as ours reinforces the need to consider IMMs in rare locations to optimize patient care.