[A case of drug-induced interstitial pneumonia caused by TS-1].

A 75-year-old man underwent right hemi-colectomy in 2003. After recurrence in November, 2005, he had been given CDDP and TS-1. He had complained of cough with white sputum and fever from the end of October, 2006, however, antibiotics did not improve his symptoms. The chest CT showed diffuse ground glass opacities (GGO) in bilateral lung fields. Steroid treatment improved his physical condition and chest x-ray. Drug-induced pneumonia caused by TS-1 was diagnosed data from a drug lymphocyte stimulation test (DLST). Drug induced interstitial pneumonia can therefore occur after long-term administration.