[Colorectal cancer. Progress and unsolved problems].

This review deals with colorectal carcinoma, the most frequent malignant tumor in western countries aside from skin cancer. Epidemiologic data confirm the crucial role of nutrition in the pathogenesis of these tumors. The pathology and natural history of colorectal cancers are reviewed. Screening programs have yielded encouraging first results. In recent years surgery of rectal cancer has been improved by the introduction of a new stapling device permitting more sphincter-saving operations. Pre- and postoperative radiotherapy as an adjuvant to surgery are important elements in the primary management of rectal carcinoma. Radiotherapy is often effective in palliating pain, bleeding, and mucous discharge. Chemotherapy of colorectal cancer is still unsatisfactory. The prospects for adjuvant chemotherapy are discussed. The often dismal outlook for patients with colorectal cancer will be more promising if etiological factors can be eliminated, early diagnosis improved and chemotherapy ameliorated.