A case of a large fibrous tumor of the breast

Abstract

A 52-year-old female was found to have a breast mass pointed on mammography screening. A firm mass, 8 cm in diameter, was palpated in her right breast. Fibroadenoma or phyllodes tumor was suspected on imaging ; an inadequate specimen was obtained on fine needle aspiration. Since malignancy could not be ruled out, a tumor resection was performed. Macroscopically, the tumor was elastic/firm, and well-defined. The cut surface was white, homogenous, and solid. On histology, the tumor consisted of collagenous stroma that contained markedly decreased or atrophic ductal and lobular elements. Based on these histologic findings, a fibrous tumor was diagnosed. The postoperative course was uneventful, and her breast had a cosmetically acceptable result. Fibrous tumor is a rare breast disease and is classified into a subtype of fibrous diseases as tumor-like lesions based on the “General rules for clinical and pathological recording of breast cancer”, 16th edition, published by the Japanese breast cancer society. A diagnosis of a fibrous tumor should be considered in patients with a large mass.