Presentation of intramuscular myxoma as an unusual neck lump

Abstract

Intramuscular myxoma (IM) has a distinct diagnostic identity among soft tissue myxomas. IMs have an approximate incidence of 1 per million of the population per year, with a female-to-male ratio of 14:3. The age range for presentation is 40 to 70 years, and the thigh is affected most frequently. IMs most commonly affect larger muscle groups, making the head and neck a rare site. To the authors' knowledge, there is 1 previous report of an IM presenting in the sternocleidomastoid muscle. In addition, IMs usually present as slow-growing asymptomatic swellings. Although abnormal gag reflexes have been reported in cases of glossopharyngeal schwannoma and neurofibroma in patients with neurofibromatosis-1, a gag reflex has not been reported previously as a complication of IM in the head and neck. A case of IM in the left sternocleidomastoid muscle, presenting with an intense gag reflex on palpation, in a 70-year-old woman is presented.