Sixteen patients with advanced small cell lung cancer who relapsed or progressed under first-line therapy, were treated with second-line chemotherapy consisting of: teniposide, 60 mg/m2, i.v. days 1-5, every 3 weeks until further progression. The response rate was: 3 minor responses, 6 stable disease, 5 progressive disease, 1 early death and 1 not evaluable. After the introduction of teniposide, median survival was 4.5 (range 1-11) months, compared to the median survival (2 months, range 1-11) observed in 40 contemporary patients of our series, who relapsed or progressed and subsequently received no treatment. The assessment of the difference was significant: chi-square = 4.05, P less than 0.05. In addition a particular comparison was performed with 15/40 patients who matched according to the major predictive parameters of disease. These patients experienced 2 months (range 1-7) of median survival which was significantly shorter than that of the teniposide treated group (chi-square = 4.48, P less than 0.05). On these bases, teniposide appeared to be effective, but the small size of the study suggests caution in evaluating the results.