1. Obviously, the radiation hazard to long-duration space travelers - and the consequent cancer risk - is a major problem. 2. This suggests that such indices are unlikely to provide useful markers for the identification of colorectal cancer risk as previously proposed. 3. A case reports and clinical-epidemiological studies have evaluated the cancer risk in patients who have abused anthranoid laxatives over a long period. 4. Biological markers are becoming increasingly important for early detection of an increased cancer risk and as intermediate end points for chemoprevention trials. 5. Another possible factor resulting in an increased gastric cancer risk is the more common use of tobacco by coal miners. 6. There is a general feeling in published studies that colitis extending beyond the splenic flexure can be regarded as extensive in terms of cancer risk. 7. To date this operation seems to be free of cancer risk although one case of cancer has been reported seven years after operation. 8. We conclude that the cancer risks per unit dose to the population in Umhausen and the uranium miners in West Bohemia do not differ considerably. |