The superiority of combination chemotherapy including etoposide based on in vivo cell cycle analysis in the treatment of extensive small-cell lung cancer: a randomized trial of 288 consecutive patients.

Two hundred and eighty-eight patients with extensive small-cell carcinoma of the lung (SCCL) were entered into a three-arm prospective randomized trial. The purpose was both to compare etoposide with methotrexate (MTX) in a combination chemotherapy regimen otherwise consisting of vincristine (VCR), lomustine (CCNU), and cyclophosphamide (CTX) and to evaluate a treatment design based on cell kinetic observations suggesting enhanced sensitivity to etoposide three to six days after administration of VCR, CCNU, and CTX. In all three treatment arms, VCR, CCNU, and CTX were administered on day 1 of a 28-day cycle. In arm A, MTX was administered on days 14 and 17, while in arm B, MTX was replaced by etoposide administered on days 14 through 17. In arm C, MTX was also replaced by etoposide, but administered on days 3 through 6. Overall survival was significantly longer for patients treated with "early" etoposide (arm C; median, 33 weeks) as compared with arm A (MTX; median, 23 weeks) (P less than .05), but not statistically different from "late" etoposide administration (arm B; median, 27 weeks). However, for patients with initial favorable performance status (0 + 1), a significantly longer survival was obtained for those treated with early etoposide (arm C. median, 51 weeks) as compared with patients in arm A (median, 32 weeks) and arm B (median, 36 weeks) (P less than .05). Two-year survival was obtained in six patients (7%) in arm C compared with three patients (3%) in arm B and none in arm A. The study confirmed that etoposide is an active drug in the treatment of SCCL and when combined with CTX, CCNU, and VCR, the cell kinetic approach of an early administration yields the best results.