[A case of advanced breast carcinoma treated with topical S-1 plus letrozole].

The patient was a 75-year-old woman. Her chief complaint was edema in the right upper arm since December 2009. The right breast displayed a skin ulcer. The local findings were apparent in the right breast and the right axilla, and palpation revealed a mass under the skin ulcer that was diagnosed as papillotubular carcinoma by needle biopsy. The classification was T4bN1M1, stage IV, ER (+), PgR (+), and human epidermal growth factor receptor type 2 score 0. Because of failed cardiac function and lubricity, S-1(80 mg/body) and letrozole(2.5 mg/po) were administered. Lymph node reduction, disappearance of ulcerated skin, tumor reduction, and upper arm lymphedema were improved markedly after drug administration, and the tumor marker level decreased. Chemotherapies cause significant side effects, and the use of medicine in elderly patients with advanced breast carcinoma is limited. A clinical partial remission was achieved by administration of S-1 as the third-line therapy. Therefore, first-line administration of S-1 may be effective in such cases.