A Rare Case: Malignant Granular Cell Tumor in Axillary Region

Abstract

Granular cell tumors (GCT) are rare soft tissue tumors. Although it is frequently seen in the upper extremity, it can be seen anywhere in the human body. The majority of tumor cases are benign and approximately 2% are malignant. It is seen in the breast at a rate of 5-8%. They present with a slow growing, painless, mobile mass. The definitive diagnosis is made histopathologically and the treatment is wide excision. A 75-year-old woman presented with an ulcerated exudative mass in the right axilla. Mastectomy and axillary dissection were performed by general surgery 8 months ago for BIRADS 3 mass that was determined on mammography in the right breast. Breast specimen was identified as a phyllodes tumor. GCT was detected in five of thirty lmph nodes in the axilla. Incisional biopsy was performed on the axillary mass. Histopathological measurements showed S-100 and CD68 positivity, eosinophilic staining in tumor cells and pleomorphic nuclei with marked nucleolus. The tumor was removed with wide excision and the defect area was closed with a splint thickness skin graft. The pathological measurements revealed that the GCT in the axilla was not a breast metastasis, it was actually malignant GCT which was originated from skin. Ki-67 proliferation index was found as 10%. Surgical margins were seen as tumor free. There were no complications in the postoperative follow-up. GCTs in the axilla are generally seen as a result of breast metastasis and the vast majority are benign. Malignant skin-derived GCT is a rare case.

Keywords

• granular cell tumor
• axillary
• rare tumors