[5-fluorouracil and colorectal tumors: use in clinical practice and the "MISURA" project]

5-fluorouracil, an antimetabolite inhibiting timidilate synthetase, is one of the most used drugs in the treatment of many solid tumor types. In particular it is still central in the treatment of colorectal cancer. Nevertheless 5-FU efficiency is limited, this is due to the rapidity of its metabolism (T1/2 10 min). Many attempts have been done to increase its efficiency: 1) combinations with other antitumor drugs have been tested, but no one showed improved response rates with respect to 5-FU alone; 2) use of biological modifiers such as folinic acid and methotrexate. They interact with the biological actions of 5-FU improving its therapeutic effects. These combinations appear to be more effective than 5-FU alone; 3) continuous infusion increases the percentage of susceptible tumor cells, it makes possible the use of a high intensity dose which is active in patients resistant to 5-FU administered as bolus-injection. There are many schedules and methods of administration of 5-FU in the treatment of CRC, each of them showing different types of toxicities. This explains why there is the need to obtain a profile of 5-FU in clinical practice. The project called MISURA is though to give us this kind of information. It will be a collection of data regarding patients affected by colorectal cancer and treated with 5-FU. The collected information will be about diagnosis; ways of use, schedules, doses and tolerability of the drug; obtained responses. The aims of the study are: 1) to evaluate the use of 5-FU in clinical practice; 2) to collect data about the use of supportive therapy; 3) to know the effective incidence and prevalence of CRC in Italy. The study is retrospective, the sample consists of all patients from the oncological departments chosen to represent the national territory. The analysis of the data will be descriptive.