Science, medicine, and the future: Colorectal CancerBMJ 1997; 314 doi: https://doi.org/10.1136/bmj.314.7098.1882 (Published 28 June 1997) Cite this as: BMJ 1997;314:1882
- Malcolm G Dunlopa, senior lecturer
- a Colon Cancer Genetics Group, Department of Surgery, University of Edinburgh and MRC Human Genetics Unit, Western General Hospital, Edinburgh EH4 2XU Malcolm.Dunlop@hgu.mrc.ac.uk
Colorectal cancer is the second commonest fatal malignancy in both sexes combined, after lung cancer. The incidence in both developed and developing countries has increased over the past few decades, and in Britain the population lifetime risk of developing large bowel malignancy is 1:25. The overall five year survival is around 40%, but survival can be as high as 70% after curative surgery. The morbidity associated with the disease and its treatment is considerable. Almost all patients require surgical resection, but palliation is the only realistic hope for the substantial proportion of patients who already have disseminated disease. Although the outlook is poor, considerable financial resources are expended in combatting the disease. The estimated annual cost of treating confirmed cases in Britain exceeds £200m ($320m). This figure substantially underestimates the true cost as it does not include money spent on excluding cancer in patients with large bowel symptoms. In addition, the recent widespread introduction of adjuvant chemotherapy will increase costs dramatically.
This review highlights recent advances in colorectal cancer research that should result in tangible benefits to the patient in the near future. However, the pace of discovery is so rapid that applications of research strategies not yet dreamt of are likely to become reality over the coming decade.
Colorectal cancer is largely an environmental disease, but genetic susceptibility has an important role. Two highly penetrant autosomal dominant predisposition syndromes, hereditary non-polyposis colorectal cancer and familial adenomatous polyposis, together account for 2-10% of all cases of colorectal cancer. Genetic loci have also recently been mapped for Peutz-Jeghers syndrome and a form of juvenile polyposis. However, some familial aggregation is less well defined and may be multifactorial or polygenic in origin or perhaps due to low penetrance autosomal dominant mutations or even recessive gene defects. I will consider the characterised dominant …