[The feasibility of CDDP administration for gastric cancer outpatients undergoing S-1/cisplatin combination therapy]

S-1/cisplatin(CDDP) combination therapy(SP therapy)(S-1: 80 mg/m2/day, day 1-21, CDDP: 60 mg/m2, day 8, q35 days) is a standard regimen for advanced gastric cancer in Japan. Hydration under hospitalization is necessary for CDDP administration to prevent renal toxicity; nevertheless, ambulatory chemotherapy has recently become commonly used. Therefore CDDP administration using a short hydration regimen for gastric cancer outpatients undergoing SP therapy has been performed in our institute. Between August 2009 and November 2011, 23 patients who were treated with SP therapy as a first line therapy and began CDDP treatment in the outpatient setting were examined, and monitored for adverse events, response rate[best objective response rate(ORR)], time to treatment failure(TTF) and overall survival. A short hydration regimen means 2,550 mL of fluid in 4 h and 55 min, and the necessity of an oral intake of more than 1,000 mL liquid per day on day 7 to 9 was explained to the patients. Grade 1/2 serum creatinine elevation occurred in 5 patients (22%), but there were no incidences of grade 3/4 serum creatinine elevation or heart failure. The best ORR was 69%, median time to treatment failure(mTTF) was 11.5 months, the 1-year survival rate was 77.8%, and the 2-year survival rate was 44.7%.CDDP administration using a short hydration regimen for gastric cancer outpatients undergoing SP therapy was considered to be feasible.