Alcohol, tobacco and breast cancer--collaborative reanalysis of individual data from 53 epidemiological studies, including 58,515 women with breast cancer and 95,067 women without the disease.

Alcohol and tobacco consumption are closely correlated and published results on their association with breast cancer have not always allowed adequately for confounding between these exposures. Over 80% of the relevant information worldwide on alcohol and tobacco consumption and breast cancer were collated, checked and analysed centrally. Analyses included 58,515 women with invasive breast cancer and 95,067 controls from 53 studies. Relative risks of breast cancer were estimated, after stratifying by study, age, parity and, where appropriate, women's age when their first child was born and consumption of alcohol and tobacco. The average consumption of alcohol reported by controls from developed countries was 6.0 g per day, i.e. about half a unit/drink of alcohol per day, and was greater in ever-smokers than never-smokers, (8.4 g per day and 5.0 g per day, respectively). Compared with women who reported drinking no alcohol, the relative risk of breast cancer was 1.32 (1.19-1.45, P<0.00001) for an intake of 35-44 g per day alcohol, and 1.46 (1.33-1.61, P<0.00001) for >/=45 g per day alcohol. The relative risk of breast cancer increased by 7.1% (95% CI 5.5-8.7%; P<0.00001) for each additional 10 g per day intake of alcohol, i.e. for each extra unit or drink of alcohol consumed on a daily basis. This increase was the same in ever-smokers and never-smokers (7.1% per 10 g per day, P<0.00001, in each group). By contrast, the relationship between smoking and breast cancer was substantially confounded by the effect of alcohol. When analyses were restricted to 22 255 women with breast cancer and 40 832 controls who reported drinking no alcohol, smoking was not associated with breast cancer (compared to never-smokers, relative risk for ever-smokers=1.03, 95% CI 0.98-1.07, and for current smokers=0.99, 0.92-1.05). The results for alcohol and for tobacco did not vary substantially across studies, study designs, or according to 15 personal characteristics of the women; nor were the findings materially confounded by any of these factors. If the observed relationship for alcohol is causal, these results suggest that about 4% of the breast cancers in developed countries are attributable to alcohol. In developing countries, where alcohol consumption among controls averaged only 0.4 g per day, alcohol would have a negligible effect on the incidence of breast cancer. In conclusion, smoking has little or no independent effect on the risk of developing breast cancer; the effect of alcohol on breast cancer needs to be interpreted in the context of its beneficial effects, in moderation, on cardiovascular disease and its harmful effects on cirrhosis and cancers of the mouth, larynx, oesophagus and liver.

Enteritis necroticans among Khmer children at an evacuation site in Thailand.

A severe illness characterised by bloody diarrhoea and intestinal dysfunction was recognised at an evacuation site on the Thai-Kampuchean border. From June, 1985, to July, 1986, the illness occurred in 62 Khmer children aged 10 months to 10 years (mean 4 years); it was characterised by bloody diarrhoea (94%), fever (90%), and abdominal pain (78%). The overall mortality rate was 58%. Among 16 children who died and underwent necropsy, small-intestinal necrosis of varying severity was found; in 5 of these children small-intestinal lesions with areas of full-thickness necrosis were seen that histologically resembled those in cases of enteritis necroticans (pigbel) in Papua New Guinea. Beta-toxin-producing Clostridium perfringens type C was isolated from 2 of 23 children from whom specimens for anaerobic cultures were collected, and antibodies to beta toxin were detected in 5 of 9 survivors but not in 10 healthy, age-matched control children. These cases show that enteritis necroticans can cause substantial morbidity and mortality outside Papua New Guinea.

Diverticular disease of the colon in a far-eastern community.

A 5-year retrospective case review and 6-month clinical observation, in a teaching and general hospital in Bangkok, Thailand, show that colonic diverticular disease is not so common as in the West and has many distinctive features. Solitary cecal diverticula are at least five times more common, accounting for about one-fourth of all diverticula of the large bowel, and show definite male preponderance and occur in younger patients. Their congenital origin is supported by the lack of association with social classes, by the finding of structural relationship with the appendix in one of the patients, and by the presence of the muscular coat. On the other hand, multiple colonic diverticulosis is essentially a disease of those above the age of 40 years and shows slight female preponderance. The diverticula appear segmental and need not originate in the sigmoid colon first. Almost all multiple diverticula show radiologic features of simple massed diverticulosis and seem to be associated with higher social classes. The differences in the pattern of diverticular disease in this series and in the West cannot be readily explained on the basis of the difference in dietary habit or psychologic stress.