Six vs twelve cycles for complete responders to chemotherapy in small cell lung cancer: definitive results of a randomized clinical trial. The "Petites Cellules" Group.

Of 320 patients with small cell lung cancer (SCLC) entered into a clinical trial of chemotherapy between January 1983 and September 1985, 106 patients achieved a complete response. The induction chemotherapy used was lomustine 60 mg.m-2 p.o., cyclophosphamide 1 g.m-2 i.v., doxorubicin 45 mg.m-2 i.v. and etoposide 150 mg.m-2 i.v., every four weeks. Lomustine was only given for the first three cycles. Seventy nine of the 106 patients still in complete response after six chemotherapy cycles were subsequently randomized to receive either six more cycles or no more treatment until relapse. In this group of 79 patients, a difference was shown from the time of inclusion between the 51 patients with limited disease and the 28 patients with disseminated disease, with overall median survivals of 395 and 165 days, respectively, (p = 0.0002). No difference was shown between the two treatment groups: the median survival was 332 days from the time of second randomization with a two year survival rate of 28% for the patients randomized to receive six more cycles and 246 days and 22% for those randomized to receive no more treatment (add 147 days to obtain overall median survival). Continuing chemotherapy for more than six cycles to patients in complete response did not improve survival.