Granular cell tumor of the heel treated with Mohs technique

BACKGROUND. Granular cell tumors, also known as granular cell myoblastomas, are uncommon neoplasms of unknown etiology. Most granular cell tumors are benign and present as solitary, painless dermal nodules of the head and neck. Few of these tumors are reported on the lower extremities and only eight cases of granular cell tumor of the foot have been reported. Of these eight, only two clinically benign granular cell tumors occurred on the heel. OBJECTIVE. The objective was to describe the first reported case of malignant granular cell tumor of the heel. METHODS. All reported cases of granular cell tumor of the foot are reviewed and clinical details of a malignant granular cell tumor of the heel are provided. RESULTS. The malignant granular cell tumor of the heel was extirpated with two stages of Mohs microscopic surgery. No recurrence was noted at 22 months. CONCLUSION. Malignant granular cell tumor of the heel is among the rarest of malignancies. In this case, the tumor appears to have been successfully treated with Mohs micrographic surgery.