Twenty-six out of 53 patients with small cell lung cancer (SCLC) who relapsed or progressed following a first treatment (induction plus maintenance), were treated by a second-line chemotherapy consisting of: Teniposide (VM26), 60 mg/m2 i.v., days 1-5, every 3 weeks until further progression. The response rate obtained in 24 evaluable patients was: 7 (29%) partial response, 4 (17%) minor response, 8 stable disease, 5 progressive disease and 2 patients with early death. In the whole group, median survival time from the start of VM26 treatment, was 4 months (range 1-11). These data were compared to the median survival (1.5 months, range 1-7) of the remaining 27 patients, the control group, who at the time of progression did not receive further treatment. The difference between survivals was statistically significant (Log-rank test: p less than 0.05). According to these data VM26 seemed to be active, but larger studies better focused on all clinical variables are needed before firm conclusions can be drawn.