ANCIENT SCHWANNOMA OF THE RIGHT AXILLARY REGION MIMICKING BREAST MALIGNANCY: A RARE CASE REPORT

Abstract

Background: Ancient schwannoma is a rare benign peripheral nerve sheath tumor characterized by degenerative changes, most commonly found in the head, neck, or extremities. Axillary localization, particularly extending to the mammary tail, is extremely rare and may clinically and radiologically mimic breast malignancy due to features commonly associated with malignancy such as an immobile, painless mass with progressive growth and indistinct borders. Case Presentation: A 37-year-old woman presented with a progressively enlarging, firm, immobile right axillary mass accompanied by intermittent paresthesia of the right forearm. Imaging revealed a heterogenous solid mass categorized as BI-RADS IV, raising suspicion for malignancy. Surgical excision was performed, and histopathological examination demonstrated characteristic features of ancient schwannoma, including Antoni A and Antoni B areas with cystic and hemorrhagic degeneration. No malignant transformation was identified. Conclusion: Ancient schwannoma in the axillary region is exceedingly rare and may clinically simulate breast carcinoma. High suspicion and histopathological confirmation are critical to avoid overtreatment. Complete surgical excision remains the definitive treatment with favorable prognosis. Thorough clinical examination, appropriate imaging, and histopathological confirmation must be prioritized to avoid misdiagnosis, especially in cases mimicking malignancy.