Doctors are still far from being able to say what causes cancer, but they suspect many things. Last week, for the first time, the American Cancer Society and the U.S. Public Health Service's National Cancer Institute got together for a national cancer conference. For three days some 400 experts talked things over in Memphis' Hotel Peabody, where, between sessions, they chatted, smoked, and watched the tamed wild ducks swimming in the lobby fountain.
Vitamins & Smoke. Diet may be "an important predisposing cause" of cancer of the mouth, said the University of Southern California's Dr. Ian MacDonald. A lack of proteins and vitamins of the B-complex family (e.g., the sort of bland diet used to treat stomach ulcers) may be the trouble. Diets rich in proteins and B-complex may help prevent it. Smoking? Possibly a minor cause of cancer of the mouth, said Dr. MacDonald.
But smoking, argued New Orleans' Dr. Alton Ochsner, can be blamed for the increase of cancer of the lung. Surgeon Ochsner, a nonsmoker, was positive. Dr. Charles S. Cameron, A.C.S. medical and scientific director, who does smoke, was not so sure. For every expert who blames tobacco for the increase of cancer of the lung, he said, there is another who says tobacco is not the cause.
Three other investigators made a preliminary report on a scientific survey, the first of its kind, in which they looked for some connection between smoking and lung cancer. Chief Surgeon Evarts Graham and Medical Student Ernest L. Wynder of Washington University's School of Medicine, and Manhattan's Dr. Herbert C. Maier, checked 200 male patients who had lung cancer, and a group of 500 without cancer. Of the 200 with cancer, 95.5% had smoked at least one package of cigarettes a day for at least 20 years; only one was a nonsmoker, and all but 3% inhaled. Of the 500 without cancer, only 50% smoked that much. The doctors also found that only one-half of 1% of the cancerous 200, but 11 % of the 500 cancer-free patients, were nonsmokers. Some 5,000 to 10,000 cases will have to be studied before they are sure, but the three researchers now say that cigarette smoking may be one of many factors in lung cancer. One big reason for present uncertainty: failure to produce lung cancer in laboratory animals by tobacco smoke.
Sun & Emotion. About 5% of all cancer is caused by environment, said the Institute's Dn A. V. Diebert. Exposure to too much sun may cause it; cancer of the skin is three times as prevalent in the South as in the North. Cancer may also be included among occupational hazards. Men who mend fishnets for a living have a high rate, added Cameron, because they hold the bobbin in their mouths, and get tar smudges on their lips. Fumes from tar-surfaced roads may also be a hazard. Pacific island natives who chew tar-bearing betel nuts have a high rate of cancer of the cheek.