This investigation of some biosocial factors such as level of education, profession, tobacco smoking, alcohol and coffee consumption, and previous illnesses, reports on 98 patients with histologically confirmed rectal cancer, and 196 hospitalized and neighborhood-matched controls. Past history of hemorrhoids, polyposis, colitis, diverticulosis and appendectomy, as well as the use of laxatives were significantly more frequent among rectal cancer patients than in their controls. None of the case-control differences related to the other parameters reached statistical significance.