Background: In our hospital, the starting dose of S-1 for patients over 75 years of age with advanced gastric cancer was determined by body surface of area, creatinine clearance, performance status(PS)and the presence of complications. The objective of this retrospective study was to investigate the proper administration of S-1 in elderly patients by comparing patients given a standard dose of S-1 to those given a reduced dose.
Methods: Twenty patients participated. Six patients were administered S-1 at a standard dose(standard group)and fourteen patients with at a reduced dose(reduced group). Safety, feasibility and anti-tumor effects were assessed.
Results: Three cases of grade 3 adverse events were found in the standard group, and one case was found in the reduced group. Time to treatment failure was 4. 4 months for the standard group and 8. 2 months for the reduced group. The overall response rate was 25% in the standard group and 30% in the reduced group.
Conclusions: It is important to reduce S-1 administration to patients over 75 years of age with caution, and take into account the patient's renal function, PS and Ccr complications.