Leucovorin plus 5-fluorouracil: an effective treatment for metastatic colon cancer.

In Columbus, OH, 46 patients with measurable metastatic colorectal cancer were treated with leucovorin (LV) 80 mg/m2/20 h intravenous (IV) infusion followed by 5-fluorouracil (5-FU) 400 mg/m2 IV bolus daily for three days and then once weekly. Many patients had liver (62%) and/or multisite metastases (53%), carcinoembryonic antigen (CEA) greater than 10 (76%), documented tumor progression before entry (51%), and tumor-related symptoms (36%), but also good performance status (84%). Prior therapy consisted of radiotherapy (RT) in 18%, chemotherapy in 22%, both in 4%, and none in 56%. There were 36% objective responses and 31% stabilization, which we believe is a significant change in the natural history of these patients. Median survival was 8 months. Improved survival was seen in patients with single- rather than multiple-site involvement. Decreasing CEA levels were seen in 59% (always in responders or patients with stable disease), and correlated with longer survival time (11.0 v 5.5 months, P = 0.01). Palliation of tumor related symptoms occurred in 75%, with or without antitumor effect. One patient with prior RT died of neutropenic sepsis after only the three-day load, so we now recommend only weekly therapy in previously radiated patients. Otherwise, toxicity was mild, manifest as weakness in 62%, nausea in 53%, or diarrhea in 47%, which was the most common dose-limiting side effect. The occurrence or absence of toxicity did not predict outcome. Because of equivalent efficacy, mild toxicity, and less expense, this regimen should be considered for patients who desire therapy.