[How I treat colorectal cancer. I. Prevention and adjuvant treatment].

Colorectal adenocarcinoma is a major cause of cancer-related morbidity and mortality in Belgium and in other western countries. Prevention implies a modification of alimentation and maybe a chronic uptake of acetylsalicylic acid. Treatment of colorectal cancers is based on surgery and the prognosis is determined by the locoregional or metastatic tumor spread. Complete resection of any Astler Coller stage C colorectal malignant tumor has to be followed by a 5-fluorouracil-based adjuvant chemotherapy. In these protocols, 5-fluorouracil is administered together with folinic acid or levamisole. The administration of an adjuvant chemotherapy could also be considered for stage BII diseases. As rectal cancers are characterized by high local relapse rates, their treatment should associate radiotherapy, given either post-surgery or preferentially pre-surgery, with resection and chemotherapy. Appropriate treatment of colorectal cancers thus requires a concerted multidisciplinary approach.