Intramuscular myxoma: a clinicopathologic study of 17 patients.

The office and hospital records of 17 patients treated for intramuscular myxomas between 1979 and the present were reviewed. Thirteen women and four men were diagnosed with an intramuscular myxoma at an average age of 55 years (range, 31-76 years). Each patient presented with a noticeable mass, and six patients had symptoms of pain or aching related to the mass. The masses were located primarily in the thigh muscles with eight in the quadriceps muscles, two in the gluteal muscles, and two in the adductor muscles. The majority (nine of 11) of the masses were relatively hypointense on T1-weighted images, hyperintense on T2-weighted images, homogeneous and well-circumscribed, and showed peripheral enhancement with gadolinium contrast. All patients were treated by marginal excision of the tumor. Fine needle aspiration biopsy correlated with final surgical diagnosis in only three of eight masses biopsied. The size of the excised tumors ranged from 3.5 to 9.5 cm. No tumors recurred during an average followup of 7 years after excision (range, 1-20 years). None of the intramuscular myxomas in the series was associated with either Mazabraud's syndrome or Albright's syndrome.