Publications

We have investigated the relation between alcohol, tobacco and dietary habits and risk of adenocarcinoma of the small intestine using data from 2 hospital-based case-control studies on intestinal cancers conducted in 6 Italian centres between 1985 and 1996. Cases were 23 patients below age 75 years with adenocarcinoma of the small intestine. Controls were 230 patients admitted to hospital for a wide spectrum of acute, non-neoplastic, non-digestive tract diseases, matched to cases on sex, age, study and centre. Odds ratios (ORs) were estimated using conditional logistic regression. Alcohol and tobacco consumption did not increase the risk of adenocarcinoma of the small intestine. The risk appeared to be directly related to intake of bread, pasta or rice (OR = 3.8), sugar (OR = 2.9) and red meat (OR = 4.6), and inversely to coffee (OR = 0.4), fish (OR = 0.3), vegetables (OR = 0.3) and fruit (OR = 0.6). Our results suggest that dietary correlates of adenocarcinoma of the small intestine are similar to those of colon cancer and at least of the same magnitude. While the present data are inconsistent with a major effect of tobacco or alcohol, a moderate association between these factors and small bowel cancer may have been obscured by the play of chance.

The relationship between diabetes mellitus and primary liver cancer was investigated in a case-control study conducted in Italy between 1984 and 1996 on 428 cases with incident, histologically confirmed hepatocellular carcinoma, 59 with gallbladder and bile duct cancer, and 1,502 control subjects in the hospital for acute non-neoplastic diseases. Sixty-four cases of hepatocellular carcinoma vs. 87 controls reported a history of diabetes, corresponding to an odds ratio (OR) of 2.3 after allowance for age, sex and area of residence, and of 2.1 [95% confidence interval (CI) = 1.4-3.2] after further allowance for alcohol and tobacco consumption, history of hepatitis and liver cirrhosis, body mass index and history of liver cancer in first-degree relatives. The ORs were similar both for subjects diagnosed with diabetes below age 45, who most likely had insulin-dependent diabetes, and for those diagnosed later, who were likelier to have non-insulin-dependent diabetes. The OR was 2.3 for subjects whose diabetes was diagnosed <5 years before diagnosis of liver cancer, 1.9 for those diagnosed 5-9 years in advance and 2.2 for those diagnosed since 10 years or more. Five cases of gallbladder and bile duct cancer reported a history of diabetes: the corresponding OR was 1.2 (95% CI 0.5-2.9). The OR of hepatocellular carcinoma was 2.4 for males and 2.0 for females, 3.0 for subjects diagnosed with liver cancer under age 60 and 1.8 for those diagnosed at age 60 or over. None of the other covariates considered, including education, history of hepatitis, liver cirrhosis and alcohol drinking showed any meaningful modifying effect or interaction. The potential pathogenic mechanisms include liver alteration-and consequent cell proliferation-in subjects with diabetes. Thus a history of diabetes mellitus could explain about 8% (95% CI 5-11) of cases of liver cancer in this population.

Istituto di Ricerche Farmacologiche “Mario Negri,” Via Eritrea 62, 20157 Milan, Italy and lstituto di Statistica Medica e Biometria, University of Milan, Milan, Italy

The characteristics of women reporting cervical cytology screening has been evaluated using data from control subjects collected in the framework of a case-control study on invasive cervical cancer conducted since 1981 in the greater Milan area. A total of 515 women admitted for nonneoplastic, non-gynecologic, nonendocrine-related acute conditions to a network of general and university hospitals were interviewed. The frequency of cervical screening utilization decreased with age: regular screening (≥ 3 lifetime Pap smears) was reported by 46% of women aged 44 years or less, but only 11% of those aged 65 or more. Married women reported about 50% more frequently occasional (1 or 2) and about three times regular (≥ 3) cervical screening than unmarried ones. Parous women were more frequently screened, but no trend emerged with number of births. Similarly number of medical consultations in the year before the interview was associated with an increased number of Pap smears. There was no consistent association between number or recency of Pap smears and smoking, sexual habits or education, but women in low social classes tended to be less frequently screened. Ever contraceptive users (oral contraceptives or barrier methods) reported an increased probability to be screened regularly and within two years before the interview.

The reasons for the worldwide decline in stomach cancer incidence and mortality rates are not fully understood, but dietary changes are clearly implicated. While the possible mechanisms of gastric carcinogenesis and the impact of Helicobacter pylori eradication remain open to debate, at least two practical recommendations - to increase fruit and vegetable intake, and to reduce consumption of salt - are already supported by epidemiological evidence. These dietary recommendations may also be beneficial in the prevention of other cancers and chronic diseases. Promising evidence of a favourable effect of certain vitamins, such as vitamin C and E and beta-carotene, and minerals, such as selenium, justifies additional investigation.