Alternating radiotherapy and chemotherapy in limited small cell lung cancer: the IGR protocols. French FNCLCC Lung Cancer Study Group.

Two-hundred two patients with limited small cell lung cancer were tested by four consecutive alternating radiotherapy and chemotherapy protocols. The alternating schedule consisted of six cycles of chemotherapy (doxorubicin, etoposide, and cyclophosphamide, plus methotrexate in the first protocol; cisplatin replaced methotrexate in the other three protocols) and three courses of thoracic radiotherapy at a total dose of 45, 55, 65 and 61 Gy in the four consecutive protocols, respectively. A 1-week rest followed each chemotherapy cycle and each course of radiotherapy. Seventy-six percent of patients were in complete remission at the end of the induction treatment. Overall results showed a 2-year cumulative incidence rate of failure of 75%. The first cause of failure was local recurrence only, 33%; distant only, 25%; distant and local simultaneously, 9%; and intercurrent death, 8%. Overall survival rate at 5 years was 16%. No significant differences were observed between the four treatment groups. Alternating radio-chemotherapy approaches are feasible and currently included in Phase III trials.