A phase II study of cisplatin and irinotecan as induction chemotherapy followed by concomitant thoracic radiotherapy with weekly low-dose irinotecan in unresectable, stage III, non-small cell lung cancer: JCOG 9706.

Objective: It is important to identify optimal regimens of cisplatin-based, third-generation chemotherapy and thoracic radiotherapy for patients with unresectable, Stage III, non-small cell lung cancer.

Methods: Patients with unresectable, Stage III non-small cell lung cancer were treated with the following regimen: cisplatin 80 mg/m(2) on days 1 and 29, with irinotecan 60 mg/m(2) on days 1, 8, 15, 29, 36, and 43 and 30 mg/m(2) on days 57, 64, 71, 78, 85 and 92. Thoracic radiotherapy was started on day 57 at 2 Gy/day (total 60 Gy).

Results: From February 1998 to January 1999, 68 patients were enrolled. Grade 3/4 toxicities during induction chemotherapy primarily included neutropenia (73.5%) and diarrhea (20.6%), while Grade 3/4 toxicities during concomitant thoracic radiotherapy with irinotecan consisted of neutropenia (18.4%), esophagitis (4.1%) and hypoxia (6.5%). There was one treatment-related death due to radiation pneumonitis. The response rate was 64.7% (95% confidence interval, 52.2-75.9%). The median survival time was 16.5 (95% confidence interval, 12.6-19.8) months. The 1- and 2 year survival rates were 65.8% (95% confidence interval, 54.4-77.1%) and 32.9% (95% confidence interval, 21.6-44.1%), respectively. Overall, only 36 (56%) completed both the scheduled chemotherapy and thoracic radiotherapy.

Conclusions: Induction chemotherapy with cisplatin plus irinotecan followed by low-dose irinotecan and concomitant thoracic radiotherapy was feasible according to the prespecified decision criteria in this study for patients with unresectable Stage III non-small cell lung cancer. We did not decide to select this regimen for further investigations because approximately half of the patients completed the scheduled treatment.