ABSTRACT
The chemotherapeutic treatment of metastatic colorectal cancer in the USA began with the discovery of 5-fluorouracil (5-FU) in the late 1950s. Single-agent activity was demonstrated using a variety of dosage administration schedules. The most widely adopted 5-FU schedules in the USA were an ‘intensive course’ (‘bolus daily 5’) regimen or a weekly schedule.1-3
Although response rates predictably varied among the various uncontrolled trials, approximately 20% of patients experienced an objective tumor response that was almost always partial and lasted only a few months. There was no credible evidence from controlled clinical trials that single-agent 5-FU could improve patient survival.
