A 57-year-old woman was referred to another hospital with bilateral breast masses. Incisional biopsy findings indicated bilateral breast invasive lobular carcinoma, with positive estrogen receptor(ER)status and negative human epidermal growth factor receptor 2(HER2)status. Close inspection did not show the presence of distant metastasis, but lymphadenopathy was noted in the left supraclavicular region, and bilateral TxN3M0, Stage IIIC breast cancer was diagnosed. We performed a simple, double mastectomy, and endocrine therapy was initiated. Treatment with anastrozole followed by tamoxifen resulted in a temporary response. Because of progression after both treatments, chemotherapy was initiated. Complete response was observed in the left supraclavicular lymph node metastases after 4 courses of docetaxel and cyclophosphamide. Two years after treatment was discontinued, metastatic breast carcinoma in the stomach was diagnosed. Immediately after fulvestrant administration, the patient complained of neck stiffness. Several examinations revealed thickening of the cervical muscles with an abnormal signal. Core needle biopsy of the cervical muscle lesion revealed the presence of metastatic adenocarcinoma, with negative ER status and negative HER2 status. Chemotherapy with capecitabine was initiated, and this resulted in stable disease.
