Synchronous and unilateral breast cancers (invasive lobular carcinoma and non-invasive ductal carcinoma) - A case report

We report a case of synchronous and unilateral breast cancers in a 51-year-old female. A focal asymmetric right breast density was detected on breast cancer screening mammography. Ultrasonography showed a low echoic mass, 9 mm in diameter, in the B area, and a second low echoic mass in the CD area of her right breast. A core needle biopsy of the B area mass led to a diagnosis of an invasive lobular carcinoma, positive for estrogen receptor (ER) and progesterone receptor (PgR), and negative for HER2/neu. One-percent of the tumor cells were Ki-67 positive. Her preoperative diagnosis was Stage I (T1N0M0). She underwent muscle-preserving mastectomy plus sentinel lymph node biopsy. The pathological diagnosis from the resected surgical specimen was invasive lobular carcinoma (B area), positive for ER, and negative for PgR and HER2/neu protein expression. From this, she was additionally diagnosed with non-invasive ductal carcinoma (CD area) that was positive for ER, and negative for PgR and HER2/neu protein expression. The surgical margins were negative, and there were no sentinel lymph node metastases. These tumors were independent. She was given adjuvant endocrine therapy. Two years and 6 months after surgery, the patient was doing well and without metastases.