[Adjuvant therapy in colorectal carcinoma].

Patients with colorectal carcinoma and histological evidence of regional lymph node involvement (N+ or Dukes' C) or tumor invasion into the adjacent pericolic or perirectal fat tissue (T3-T4 or Dukes' B2-B3) still have an unfavourable prognosis if treated by surgery only. In colonic cancer, several clinical studies carried out in the early 1980s using postoperative chemotherapy showed no therapeutic benefit. Only the combination of 5-fluorouracil and levamisole, used in two large randomized studies, resulted in a significant prolongation of the disease-free interval and overall survival in patients with Dukes' C colonic cancer. This treatment has few side effects. In patients with rectal cancer, it was the combination of chemo- and radiotherapy which led to therapeutic improvement: the incidence of local relapses--often very painful and distressing for the patient--was significantly reduced and overall survival prolonged. However, this combined treatment modality carries the risk of delayed toxicity with complications mainly involving the small bowel. It is the general practitioners' duty to decide, together with the specialists involved, whether an individual patient with colonic or rectal cancer appears suitable for such adjuvant treatment.