A phase I study of combination chemotherapy using TS-1 and pirarubicin (THP) for advanced gastric cancer

The safety of chemotherapy combining TS-1 and pirarubicin (THP) for treatment of recurrent or locally advanced gastric cancer was evaluated. THP was administered by intravenous drip infusion at a dose of 14 mg/m2 every other week. TS-1 was administered orally at a dose of 40 mg/m2 twice a day for 2 weeks followed by 2 weeks of rest (level 1), for 3 weeks followed by 2 weeks of rest (level 2), and for 4 weeks followed by 2 weeks of rest (level 3). Three patients were treated with the level 1 schedule. One patient with peritoneal dissemination received 22 courses of the treatment, and benefited from a long-term NC. However the remaining 2 cases were diagnosed as PD after 4 courses and were withdrawn from further treatment. Two patients in this group suffered from grade 2 adverse events according to the NCI-CTC. Only 1 patient who had liver metastasis was treated at level 2. Fourteen courses were administered, and a PR was achieved while grade 2 adverse events were observed. One of 3 patients who were treated with level 3 had grade 3 adverse events. Consequently, 3 more cases were added to this dose level, and no additional grade 3 adverse events were observed, while grade 2 adverse events were seen in 4 cases. Urinary urgency had completely disappeared in 1 patient with peritoneal recurrence. Myelosuppression, which was the main observed adverse event, was well controlled and of brief duration. The response, including alleviation of clinical symptoms, was confirmed in 3 of 5 chemo-naive patients.