Purpose: The aim of this study was to determine the role of chemotherapy dose intensity in patients with initially unresectable non-metastatic non-small-cell lung cancer (NSCLC), with survival as primary end point, by testing two different regimens as induction chemotherapy followed by thoracic irradiation.
Patients and methods: Patients had pathologically proven NSCLC, an initially unresectable non-metastatic tumour without homolateral malignant pleural effusion, no prior history of malignancy and had received no prior therapy. Treatment was randomised for chemotherapy between three courses of MIP (mitomycin C 6 mg/m2; ifosfamide 3 g/m2; cisplatin 50 mg/m2) or SuperMIP (mitomycin C 6 mg/m2; ifosfamide 4.5 g/m2; cisplatin 60 mg/m2, carboplatine 200 mg/m2), followed by chest irradiation (60 Gy; five times per week, for 6 weeks). If the tumour became resectable after chemotherapy, surgery was performed, followed by mediastinal irradiation.
Results: A total of 351 patients were eligible: 176 in the MIP arm and 175 in the SuperMIP arm, with 43% and 51% stages IIIA and IIIB, respectively. There was a significantly higher objective response rate with SuperMIP (46%) compared with MIP (35%) (P=0.03) [95% confidence interval (CI) for the difference between the response rates, 1% to 22%]. After induction chemotherapy, surgery was performed in 54 (15%) patients (27 per arm) and chest irradiation in 203 (57%) patients (102 in the MIP arm and 101 in the SuperMIP). In terms of survival, there was no statistically significant difference between the two study arms (P=0.16), with median survival times of, for MIP and SuperMIP, respectively, 12.5 (95% CI 10.1-14.9) and 11.2 (95% CI 9.7-12.8) months. Haematological toxicity and dosage reductions were higher with SuperMIP, which was nevertheless associated with a significantly increased absolute dose intensity.
Conclusions: High dose-intensity induction chemotherapy does not improve survival in initially unresectable non metastatic NSCLC.