Treatment of small cell lung cancer with induction chemotherapy followed by late intensification.

Seventy-seven patients with small cell lung cancer were entered on a protocol comprising induction chemotherapy with cyclophosphamide 1 g m-2, adriamycin 40 mg m-2 and vincristine 1.4 mg m-2 (CAV) every 21 days for four to six cycles. The overall response rate was 72.8%. Twenty-six patients achieving complete remission received intensification with two further cycles of ifosfamide 5 g m-2, mesna 8 g m-2, methotrexate 30 mg m-2 and etoposide 100 mg m-2 per day for 3 days (IME). Six of the 15 patients in partial remission following CAV achieved a further remission on IME (response rate 40%). Median survival in the limited disease group was 11 months compared with 7 months in the extensive disease patients and four patients are alive at more than 2 yr follow up. There was no significant prolongation of the median survival (11 months) seen in those patients in complete remission who had negative second bronchoscopy examination. This sequential six drug regime produces high response rates in small cell lung cancer, and there is evidence of lack of cross-resistance between CAV and IME.