Cancers of the large bowel: associated disorders in individuals.

The individual medical histories in the files of the Oxford Record Linkage Study for the years 1963 to 1967 were analyzed to ascertain any previously unsuspected associations between cancers of the large bowel and other diseases in individuals, and to quantify the relative risks of disorders already known to be associated. In males significant associations were shown between cancers of the large bowel and cancer of the prostate. In females, cancer of the colon was associated with breast cancer, and cancer of the rectum with a mixed group of genital cancers. The relative risk of colorectal cancer associated with previous benign neoplasms of the large bowel was 20, and with ulcerative colitis, 25. There was no significant association with appendicitis or long-standing diverticular disease.