Granular cell myoblastoma

Ninety-five patients with granular cell myoblastoma have been seen at Memorial Hospital from 1934-1965. Their ages ranged from 11 months to 68 years, an average of 38.1 years. Symptoms were present from a few days to more than 5 years and principally consisted of the presence of a painless mass in 85 patients. The lesion is ubiquitous and of the 110 lesions, 51 arose in the head and neck, 19 in the arm, 24 in the chest wall and breast, 2 in the abdominal wall, 3 in the perineum, 7 in the leg, and 4 in miscellaneous sites. Multiple lesions were noted in 8 patients. Lesions varied from minute to 5.5 cm in diameter, with an average of 1.85 cm. Initial wide surgical excision was successful in 91 patients. Two more were salvaged by subsequent re-excision. Three malignant lesions were encountered, one of which recurred and was cured by re-excision. The other 2 failed all treatment. Follow-up varied from 0 to 21 years with an average of 44.6 months. Granular cell myoblastoma is an uncommon lesion of uncertain histogenesis, almost universally benign and cured by adequate local resection.