Malignant peripheral nerve sheath tumor (MPNST) of the breast without Von Recklinghausen’s neurofibromatosis (VRN) is extremely rare. The authors report a 19 year-old woman who presented with a 12 month history of a painless mass of the left breast. Tissue biopsy was performed. The histologic diagnosis was made with immunohistochemical study in which the tumor showed positivity of vimentin, S-100 protein, neuron-specific protein(NSE), neurofilament protein(NF) and glial fibrillary acidic protein(GFAP). The patient was referred for radiation therapy after simple mastectomy.

Keywords: Breast tumor, Malignant peripheral nerve sheath tumors, von Recklinghausen’s neurofibromatosis