The outcome of surgery for adenosquamous carcinoma of the lung in 39 patients treated in 1982-1996 was compared with results in squamous cell carcinoma and adenocarcinoma. Adenosquamous carcinoma comprised only 4.2% of all 914 resected primary lung cancers. The cumulative 5-year postoperative survival rate was 22.6% for the adenosquamous tumours. Comparison of survival curves with those for squamous cell carcinoma and adenocarcinoma indicated non-significant differences. The incidence of lymph-node metastasis was significantly higher in the patients with adenosquamous carcinoma than in the other patient groups.