Background: Extensive-stage small cell Lung cancer (SCLC) is a highly aggressive malignancy for which little therapeutic progress has been made over the past 20 years. SCLC is a highly angiogenic tumor and targeting angiogenesis is being investigated. The putative mechanism of action of thalidomide is through inhibition of new blood vessel formation. This trial was designed to evaluate thalidomide in ES-SCLC. Patients and methods: Patients who had received first-line chemotherapy without disease progression were eligible. Patients received thalidomide 200 mg daily as maintenance therapy starting 3-6 weeks after completion of chemotherapy. Results: Thirty patients were enrolled. Toxicity was minimal with grade 1 neuropathy in 27% of patients and only one case of grade 3 neuropathy. Median survival from time of initiation of induction chemotherapy was 12.8 months (95% CI: 10.1-15.8 months) and 1-year survival of 51.7% (95% CI: 32.5-67.9%). Median duration on thalidomide was 79 days. Conclusion: Thalidomide 200 mg daily is well tolerated when given as maintenance therapy for ES-SCLC after induction chemotherapy. Further evaluation of anti-angiogenic agents in SCLC is warranted. (c) 2007 Elsevier Ireland Ltd. All rights reserved.