Fifty-five patients with advanced colorectal cancer were treated with the combination of leucovorin (LV), fluorouracil (FU) and dipyridamole (DP). Two (4%) patients achieved a clinical complete remission, 4 (7%) a partial remission, 24 (44%) had stable disease while 25 (45%) patients progressed during the chemotherapy period. Median survival was 47 weeks and median time to progression 19.5 weeks. Major toxicities included diarrhea (66%), leukopenia (45%), anemia (50%) and nausea/vomiting (44%). In conclusion, the addition of oral DP does not appear to improve the efficacy of the standard LV/FU regimen in patients with advanced colorectal cancer.