BACKGROUND: Incurable rectal cancer often reduces the quality of life because of obstruction, bleeding, pain and tenesmus. For such symptoms palliative therapy is often carried out. METHODS: From 1986 to 1995, 219 patients, 118 men and 101 women, mean age 67 years, with distal colorectal adenocarcinoma were referred for palliative endoscopic laser therapy. In this retrospective analysis of outcome, patients were allocated to 3 subgroups according to their dominant symptom: obstruction, bleeding and others (soiling, diarrhea, tenesmus). After initial successful treatment, maintenance therapy was carried out in cases of obstruction at intervals of 2 to 4 months; patients with bleeding, tenesmus or diarrhea were retreated if there was recurrence of symptoms. RESULTS: Initial successful palliation was obtained in 198 patients (92%), with similar results in the 3 subgroups. Long-term, effective palliation was achieved in 160 patients (75%) of the total study population. Seventy-six patients (65.0%) with obstruction, 63 (82.9%) with bleeding and 21 (80.8%) with other symptoms remained symptom free until death or this analysis of results. There was a significantly negative relation between long-term successful outcome and local spread of the tumor in the obstruction (p = 0.040) and bleeding groups (p = 0.014). The total number of treatments was significantly higher if obstruction was present at presentation (p< 0.05) and if tumors were circumferential (p = 0.05). Major complications were perforation (4.1%), fistula (3.2%), abscess (1.7%) and bleeding (4.1%). There were 5 (possibly) procedure-related deaths. The survival rate was 44.4% at 1 year and 20.4% at 2 years. CONCLUSIONS: Laser therapy is effective for initial palliation but careful patient selection is necessary. Long-term palliation is less feasible in patients with obstruction.