Malignant granular cell tumor with breast metastasis: A case report and review of the literature

Abstract

Abstract. Malignant granular cell tumors (MGCT) are rare mesenchymal soft tissue neoplasms of Schwann cell origin without adequate follow-up. This study describes a case of MGCT with right breast metastasis following two local recurrences. The patient consented to a right breast lumpectomy with right axillary dissection, a right abdominal wall lumpectomy and a right inguinal lumpectomy with dissection. Pathological examination revealed that the two initial lesions were consistent with benign histological performance. The later lesions were classified as malignant due to the observation of spindling of the tumor cells, vesicular nuclei with large nucleoli and increased mitotic rate. Immunohistochemical study of the lesions revealed positivity for S100 protein. The Ki-67 proliferation index increased from 1 to 10%. Twenty-seven months after surgery, the patient was in good health with no sign of further tumor development. We recommend wide local excision with regional lymph node dissection as the first choice of treatment for MGCT.

Granular cell tumor in axillary region: A rare entity

“…Chen et al (6) and Akahane et al (12) described malignant GCTs in breast. Criteria for malignancy are not consistent; adjacent tissue and/or vascular invasion, high mitotic activity, and size >4-5 cm were discussed, but only the presence of metastases was accepted as explicit criterion (6,7). No data exist about the efficacy of adjuvant therapy in GCT treatment.…”

“…Recently, Costa Almeida et al (7) published a case report of GCT on the upper limb and reviewed 21 patients with this GCT localization from the literature. When occurring in the breast, as it occurs in 5-8% of all cases of GCT, they present mostly as painless rounded nodules (4,6). GCT of the breast may mimic breast cancer both clinically and radiologically (8-10).…”

“…GCTs account for an incidence of 0.5% among soft tissue tumors (3)(4)(5)(6). It may occur throughout the body, usually in the head and neck, skin or subcutaneous tissues of the trunk and upper extremities.…”

“…5-8% of all cases of GCTs occur in the breast (5,6). They are usually benign and solitary; however, approximately 2% occur as malignant tumors, and 5-10% as multiple lesions (6). It is important to differentiate between this tumor and breast carcinoma because they share similarities in the diagnostic picture.…”

“…These tumors may occur throughout the body, usually in the head and neck, skin or subcutaneous tissues of the trunk and upper extremities, breasts and female genital region. 5-8% of all cases of GCTs occur in the breast (5,6). They are usually benign and solitary; however, approximately 2% occur as malignant tumors, and 5-10% as multiple lesions (6).…”