Chemotherapy as a complement to surgery or adjuvent chemotherapy has been presented as one of the possible means of improving 5 years survival rates following the excision of a digestive tract carcinoma. Started early after excision, and given in adequate doses for a period of one to two years, it is aimed at treatment of residual sub-clinical disease. Its effectiveness may be assessed only by study of the reduction in the number of recurrences or metastases in a large number of patients treated. At the present time, published series have not made it possible to define whether there is a definite reduction in the percentage of recurrence and metastases or merely a prolongation of the clear period which precedes their clinical manifestation. The practical difficulties of treatment, together with its possible early or late toxicity, are such that it should be reserved for forms in which there is some doubt as to the prognosis. The addition of immunotherapy has to be defined.