تلخیص
A case of lobular carcinoma in situ (LCIS) arising within a fibroadenoma. Diagnosis of LCIS was made based on histopathological examination of the excised lumps. The case report highlights the role of histopathology in the diagnosis of this entity coexisting in a fibroadenoma, as ultrasound missed the presence of pre-malignant cells. Fibroadenomas have genetic correlation, as was defined in our case. This case stresses the need for histological evaluation of all breast masses in women.