Abstract
Fibroadenomas are the most common benign breast lesions in adolescent and young women. It is most frequently observed in the 3rd decade. Although it is considered benign, evidence of malignant transformation is available. Cancer development may be from ground of fibroadenoma or near breast tissue. A case of a fibroadenoma coexisting with an invasive ductal carcinoma of the breast in a 31-year-old female is presented. The patient presented with the chief complaint of having a palpable mass in her right breast for the last 10 years. Mammography revealed a mass with microcalcifications. Core biopsy was performed, and the results indicated an invasive carcinoma. Breast-conserving surgery with sentinel lymph node biopsy was performed. The pathological features revealed a fibroadenoma coexisting with an invasive ductal carcinoma. This case suggests that clinicians and radiologists should always pay attention to the associated malignant imaging characteristics whenever a mass was followed up as fibroadenoma.