Here we present a case of de novo Stage Ⅳ breast cancer successfully treated with surgery and multiple endocrine therapies over a long period of time. A 75-year-old female presented with a breast tumor with skin invasion and multiple lung metastases. Diagnosed with infiltrating breast cancer of Luminal A-like subtype, endocrine therapy with anastrozole was initiated. Despite initial response to the treatment in both the primary site and lung metastases, the primary tumor regrew and surgery with lumpectomy was performed. After a 3-year-treatment of tamoxifen, axillary lymphadenopathy and bone metastases developed. The patient was treated with fulvestrant for 5 years, resulting in clinical complete response. The now 88-year-old patient has been free of disease without treatment for a year and a half. Generally, primary tumor resection of Stage Ⅳ breast cancer does not improve prognosis, but in this case it provided good local control and enabled long-term endocrine therapy, resulting in prolonged disease-free survival.