Risk factors for male breast cancer (United States).

OBJECTIVES: The etiology of male breast cancer is obscure, although an excess risk has been associated with Klinefelter syndrome, testicular disorders, benign breast disease including gynecomastia, use of exogenous estrogens, radiation, and a family history of male or female breast cancer. We conducted a case-control study to investigate risk factors further for breast cancer in men. METHODS: Based on data from the 1986 National (United States) Mortality Followback Survey (NMFS) of almost 20,000 deceased adults (age 25 years or over), we compared information obtained from next-of-kin interviews of 178 men who died of breast cancer with that of 512 male controls who died of other causes. Information was obtained on selected demographic and other factors, including diet, exercise, occupation, height and weight, and use of tobacco and alcohol. RESULTS: Increased risks were found for men who were described by their next-of-kin as very overweight (odds ratio [OR] = 2.3, 95 percent confidence interval [CI] = 1.1-5.0). The risks associated with the three upper quartiles of body mass index (BMI) (wt/ht2) were 1.3, 1.6, and 2.3, respectively, with a significant dose-response relationship (P < 0.01). An excess risk was also associated with limited exercise (OR = 1.3, CI = 0.8-2.0). Consumption of red meat was associated with an increased risk, and consumption of fruits and vegetables with a decreased risk, although the trends were not significant. No association was found for tobacco or alcohol use, but an excess risk was associated with higher levels of socioeconomic status (SES) (OR = 1.8, CI = 1.1-3.0). CONCLUSIONS: Our study suggests that obesity increases the risk of male breast cancer, possibly through hormonal mechanisms, while dietary factors, physical activity, and SES indicators also deserve further investigation.

Risk factors for colorectal cancer in a prospective study among U.S. white men.

The association of diet, smoking/drinking and occupation with subsequent risk of fatal colorectal cancer was investigated in a cohort of 17,633 white males aged 35 and older, who completed a mail questionnaire in 1966. During the subsequent 20 years of follow-up, 120 colon cancer and 25 rectal cancer deaths were identified. Due to small numbers, no significant dose-response trends were observed in the study, but risk of colon cancer was elevated among heavy cigarette smokers (> or = 30/day; RR = 2.3, 95% CI 0.9-5.7), heavy beer drinkers (> or = 14 times/month; RR = 1.9, 95% CI 1.0-3.8) and white-collar workers (RR = 1.7, 95% CI 1.0-3.0) or crafts workers within service and trade industries (RR = 2.6, 95% CI 1.1-5.8). In addition, an increased risk was seen for those who consumed red meat more than twice a day (RR = 1.8, 95% CI 0.8-4.4). Risk patterns for cancers of the colon and rectum combined were similar to those reported for cancer of the colon, but the estimates were somewhat dampened. Our findings support previous reports that a high intake of red meat and a sedentary life-style may increase the risk of colon cancer.

Risk factors for adrenal cancer: an exploratory study.

Adrenal cancer is a heterogeneous group of neoplasms with unknown etiology. In search of risk factors, we conducted a case-control study based on data from the 1986 National Mortality Followback Survey, which included a questionnaire sent to the next of kin of almost 20,000 deceased adults (age > or = 25 year) in the United States. Information was obtained on a large number of items, including use of cigarettes, alcohol, oral contraceptives (OCs), height and weight and food consumption patterns. A total of 176 subjects who died of adrenal cancer (88 men and 88 women) and 352 controls (176 men and 176 women) who died of causes unrelated to smoking, drinking or OCs (for female controls) were included in the study. Although information on histologic type was not available, most cases were estimated from incidence surveys to be adrenocortical carcinoma, with a small percentage being malignant pheochromocytoma or neuroblastoma. An increased risk was associated with heavy smoking (> or = 25 cigarettes/day) among men (odds ratio [OR] = 2.0, 95% confidence interval [CI] 1.0-4.4) but not women. No clear association was seen for alcohol use, height and weight or food consumption patterns in either sex. Among women, increased risks were found for ever users of OCs (OR = 1.8, 95% CI 1.0-3.2) and especially those who used them before age 25 (OR = 2.5, 95% CI 1.2-5.5). When the analysis was restricted to subjects with spousal respondents, more pronounced risks were seen for ever users of OCs and for those who used OCs before age 25. Our findings suggest that cigarette smoking and use of OCs may increase the risk of adrenal cancer, but additional studies are needed with more detailed information on risk factors and histologic type of adrenal cancer.

A cohort study of smoking, alcohol consumption, and dietary factors for pancreatic cancer (United States).

Risk factors for pancreatic cancer were evaluated in a cohort study of 17,633 White men in the United States who responded to a mailed questionnaire in 1966 and were followed-up through 1986 for mortality. Cigarette smoking and alcohol consumption were found to be important risk factors for pancreatic cancer. Risks increased significantly with number of cigarettes smoked, reaching fourfold for smokers of 25 or more cigarettes per day relative to nonsmokers. Alcohol intake also was related significantly to risk, with consumers of 10 or more drinks per month having three times the risk of nondrinkers, but dose-response trends among drinkers were not smooth. Coffee consumption was unrelated to risk. Dietary analyses revealed a rising rate of pancreatic cancer mortality with increasing consumption of meat after adjustment for other risk factors. Men in the highest quartile of meat intake had about three times the risk of those in the lowest quartile. No consistent association, however, was observed for consumption of fruits, vegetables, or grains. This study confirms cigarette smoking as an important risk factor for pancreatic cancer, and provides evidence that elevated intake of alcohol and meat may increase the risk of this fatal malignancy.

Parity and primary liver cancer among young women.

PIP: Researchers from the US National Cancer Institute compared data on 25-49 year old US women who died of primary liver cancer between 1985 and 1986 with data on age matched controls who died of causes other than liver conditions or oral contraceptive (OC) related conditions to determine the association between primary liver cancer and parity. Women who had experienced at least 1 live birth wear 1.9 times more likely to have died of primary liver cancer than were nulliparous women. The association was not significant (p=.22), however. The highest risks were among children with at least 6 children (odds ratio [OR]=2.9) and with 2 children (2.1). Further the risks were greater when the parents or spouse completed the questionnaire and the association almost reached significance (p=.07). This may have been due to parents and spouse providing more complete information than a friend or neighbor. The risks of developing primary liver cancer were higher among women who had never used OCs than they were among those who ever did. For example, the OR for never users past parity 2 was 3.6 compared with 1.3 for ever OC users. There was a higher risk associated with parity among long term OC users (=or 5 years) than with short-term OC users, however. The researchers concluded that since parity was positively associated with increased risk of primary liver cancer in the US (a low risk country), endogenous hormones may contribute to liver cancer development. The following facts add to this plausibility. Estrogen profiles of parous women are different from those of nulliparous women. Estrogen levels rise considerably during pregnancy. Estrogens alter liver metabolism. Pregnancy makes the body more defenseless against hepatitis and its sequelae. In low risk countries, the risk of primary liver cancer rises among women using exogenous hormones.^ieng

Is cigarette smoking a risk factor for non-Hodgkin's lymphoma or multiple myeloma? Results from the Lutheran Brotherhood Cohort Study.

Among 17,633 U.S. white male insurance policy holders whose use of tobacco was characterized in a 1966 self-administered questionnaire, there were 49 deaths from non-Hodgkin's lymphoma (NHL) and 21 from multiple myeloma (MM) during a 20-year follow-up. Men who had ever smoked cigarettes had an elevated mortality from NHL (RR = 2.1; CI = 0.9-4.9), with risk almost four-fold greater among the heaviest smokers (RR = 3.8; CI = 1.4-10.1) compared with those who used no tobacco. In contrast, risk of MM was only slightly elevated among those who had ever smoked cigarettes (RR = 1.3; CI = 0.4-3.9) and without evidence of a dose-response trend. Since this is the first cohort study suggesting a link between cigarette smoking and NHL and findings from case-control studies have been inconsistent, additional clarification should be sought from larger incidence-based cohort investigations.

Oral contraceptives and primary liver cancer among young women.

The association of oral contraceptive use with liver cancer was examined in a study of 76 deaths from primary liver cancer, 22 deaths from cancer of the intrahepatic bile ducts, and 629 controls among women aged 25 to 49 years. The subjects in the study are from the 1986 National Mortality Followback Survey, which included a questionnaire sent or administered to the next-of-kin of almost 20,000 deceased individuals in the United States. Information on a number of lifestyle factors was collected, including questions on oral contraceptive use. Increased risks of primary liver cancer were found for ever-users (odds ratio [OR] = 1.6, 95 percent confidence interval [CI] = 0.9-2.6), and for long-term (greater than or equal to 10 years) users (OR = 2.0, CI = 0.8-4.8) of oral contraceptives. When the analysis was restricted to subjects whose spouse or parent was the respondent, more pronounced risks were seen for ever-users (OR = 2.7, CI = 1.4-5.3) and long-term users (OR = 4.8, CI = 1.7-14.0). No clear excess risk was found for cancer of the intrahepatic bile ducts. This study, the largest to date, adds to the number of investigations demonstrating an increased risk of primary liver cancer with use, particularly long-term use, of oral contraceptives.

Cigarette smoking and leukemia: results from the Lutheran Brotherhood Cohort Study.

In a 20-year follow-up (1966-86) of 17,633 White males who described tobacco use in a mailed questionnaire sent in 1966, there were 74 deaths from leukemia (including 30 myeloid, 30 lymphatic, and 14 other and unspecified leukemia). Among men who ever smoked cigarettes, increased risks were observed for lymphatic (relative risk [RR] = 2.7), and other and unspecified leukemia (RR = 1.5); risks rose with increasing number of cigarettes smoked, although the dose-response relationship was statistically significant only for total leukemia. Mortality from myeloid leukemia was not elevated, except among those smoking over a pack of cigarettes per day. Results from this cohort support a relationship between cigarette smoking and leukemia. Further studies are needed to elucidate subtype associations with cigarette smoking.