From January 1987 to December 1990, 26/105 previously untreated patients affected by small cell lung cancer (SCLC), not suitable for intensive SCLC treatment since 19 of them were older than 70 years and 7 suffered from severe chronic diseases, received induction therapy consisting of teniposide alone, 60 mg/m2 on days 1-5, every 3 weeks until disease progression. After a minimum of two courses, 24 patients were evaluable for response: 13 with limited disease (LD) and 11 with extensive disease (ED) (2 patients were unevaluable: 1 early death and 1 protocol violation). Response rate, by disease stage, was: in the 13 LD, 1 complete response (CR), 8 partial responses (PR), 2 minor responses and 2 failures; in the 11 ED, 1 CR, 4 PR and 6 failures. The overall response rate was 58% (14/24) (95% confidence limits = 38-78%), comprising 8% CR and 50% PR. Median duration of response was 7 months (range 2-32). Median overall duration of survival was 9 months (range 1.5-36+). Toxicity was haematological WHO grade III in 13% of courses delivered, whereas no further important side-effects were recorded, excluding alopecia, which was common. Teniposide used alone appeared a safe and effective palliative treatment for poor-risk patients; the major limitation was the low CR rate.