Granular Cell Tumor of the Hand: Unusual Malignancy of a Previous Benign Lesion: A Case Report.

CASE: Malignant granular cell tumors are uncommon soft-tissue tumors. We describe a granular cell tumor that presented as a benign hand nodule diagnosed by biopsy and image. The patient refused local excision. After 15 years, the patient came back because of symptomatic growth, and a malignant granular cell tumor was diagnosed, with metastatic disease. Despite surgical disarticulation and adjuvant treatment, she died after 8 months. The pathological examination revealed the tumor had progressed to malignant behavior. CONCLUSIONS: Our findings highlight the importance of a closer follow-up. Although unusual, we must be aware of the possibility of a change of behavior from benign to malignant granular cell tumor.