[Elderly Advanced Breast Cancer Effectively Treated with Locoregional Therapy-A Case Report]

We report a case of advanced breast cancer in an elderly patient effectively treated with locoregional therapy. The patient was an 81-year-old woman who presented with an increasing right breast lump. The tumor was 55 mm in diameter, accompanied by fixation to pectoral muscle. A core needle biopsy for right breast tumor led to a diagnosis of mucinous carcinoma, positive for estrogen receptor(ER)and progesterone receptor(PgR), negative for HER2/neu. The Ki-67 positive cell index was 10%. A bone scintigraphy revealed multiple bone metastases, so, we confirmed the diagnosis as T4cN2aM1, Stage Ⅳ. She initiated endocrine therapy by letrozole. By changing the endocrine therapy to toremifene followed by fulvestrant, the therapy achieved a partial response. However, the size of the primary tumor increased accompanied by bleeding, and surgical resection of the right breast was performed for local control. The locoregional surgery was effective, improving the patient's quality of life. She was administered lapatinib as anti-HER2 therapy in addition to the endocrine therapy. Two years and 6 months after surgery, there has been no worsening of bone metastasis or appearance of visceral metastasis.