[Adjuvant therapy of colon and rectal cancer. Overview of current status]

Colorectal cancer is the most important gastrointestinal tumour regarding incidence and mortality rate in Western Europe and the U.S. Long term results of treatment have not impressingly changed over the last few decades, at least half of all the patients with curative surgery finally succumbing to recurrence of their disease. Evaluating prospective randomized studies, an attempt has been made to summarize the current status of adjuvant therapy in colorectal cancer. For rectal cancer, combined postoperative chemotherapy and radiotherapy has proven benefit in one study reducing the overall relapse rate and improving disease-free survival. There is also an established benefit in the management of primarily inoperable rectal tumors where high dose radiation therapy renders some of these cases operable. Further studies of adjuvant treatment for rectal cancer are needed to evaluate the optimal radiation schedule and to limit the side effects of the treatment. Adjuvant therapy of colon cancer must still be regarded as unsettled. The lack of efficient systemic treatment for disseminated and recurrent disease favor the localized liver-directed adjuvant measures (perfusion, irradiation) in studies which are followed with interest. Up to date, adjuvant colon cancer trials strongly need a surgery-only control group. Unfortunately, there is as yet no proven significant benefit from immunotherapy as an adjuvant therapy for colorectal cancer, but further basic and clinical studies will be of great interest in this field. Regarding the current status of adjuvant therapy in colorectal cancer, there is a slight optimism that multimodality treatment may improve the survival of rectal cancer patients, and further studies in prospective randomized trials are urgently needed.