Search

The purposes of this study were to determine whether exposure of the vestigial male breast to ionizing radiation is associated with an increase in risk of breast cancer and, if so, to determine whether the apparent effects on risk in men are similar to those reported for women. A population-based case-control study of breast cancer in men was conducted in 10 geographic areas of the United States. Information on possible prior exposure to ionizing radiation, and on other potential risk factors for breast cancer, was obtained from personal interviews of 227 cases and 300 controls who were recruited from October 1983 to September 1986. Evidence from this study that ionizing radiation can cause breast cancer in men includes: a modest trend of increasing risk with frequency of chest X-rays; an increase in risk in men with three or more radiographic examinations, especially if received prior to 1963; and an increase in risk in men who received X-ray treatments to the chest and adjacent body areas. Risk was increased only from 20 to 35 years after initial exposure from either radiographic examinations or X-ray treatments, and declined after three to four decades since last exposure, suggesting a wave of increased risk of finite duration following exposure. The doses of radiation received could not be estimated precisely, but those from diagnostic procedures were likely similar to those received by prepubertal females in prior studies, and the results of those and the present investigation are compatible. The carcinogenic effects of ionizing radiation may be similar in the male and prepubertal female breast.

Histologic slides from 282 incident cases of breast cancer in men, that were identified in 10 population-based cancer registries in the United States, were reviewed by a single pathologist. Breast cancer more often presented in the noninvasive stage in men (10.8 percent of all cases) than would be expected among women. All noninvasive carcinomas were of the ductal type. Of invasive carcinomas, compared with women, men had smaller proportions of lobular and mucinous types and larger proportions of ductal and papillary types and Paget's disease. No case of tubular or medullary carcinoma was seen. The breast in men is composed only of ducts and normally contains no lobules, and the histologic types of breast carcinomas that predominate in men are likely of ductal origin. Estrogen and progesterone receptors were present in 86.7 percent and 76.3 percent of invasive carcinomas, respectively, which are higher proportions than would be expected among women. Also, unlike findings in women, receptor content was not associated with patient age at diagnosis.

Cases included in a population-based case-control study of breast cancer in men were recruited from 10 geographic areas of the United States from 1983 to 1986. Controls, matched to cases on age and geographic area, were selected by random digit dialing for men under age 65 years and from Health Care Financing Administration files for older men. Results are based on responses from 227 cases and 300 controls to questions asked in a standardized personal interview. An increased risk of breast cancer was most strongly associated with undescended testes and was also related to orchiectomy, orchitis, testicular injury, late puberty, and infertility; and a decreasing trend in risk was observed with an increasing number of children. Relative risk estimates were also elevated in relation to a history of high blood cholesterol, rapid weight gain, benign breast conditions, and possibly obesity. These findings suggest that breast cancer in men develops in response to androgen deficiency associated with testicular dysfunction and under conditions associated with excess estrogen. Risk was also found to be elevated in men with a history of amphetamine use, diabetes, and cigar smoking and reduced in men with prior head trauma.

Data from a population-based case-control study of breast cancer in men were used to examine the hypothesis that occupational exposure to electromagnetic fields increases the risk of breast cancer. Incident cases (n = 227) diagnosed between 1983 and 1987 were obtained from 10 population-based cancer registries of the Surveillance, Epidemiology, and End Results program of the National Cancer Institute. Controls (n = 300) were selected by random digit dialing and from Medicare eligibility lists. Exposure status, defined as ever having been employed in a job which has been classified as involving potential exposure to electromagnetic fields, was assigned without knowledge of case/control status. An elevated risk was found for any job with exposure (odds ratio (OR) = 1.8, 95 percent confidence interval (CI) 1.0-3.7), and risk was highest among electricians, telephone linemen, and electric power workers (OR = 6.0, 95 percent CI 1.7-21) and radio and communications workers (OR = 2.9, 95 percent CI 0.8-10). Risk did not vary with duration of exposed employment. The risk was highest among subjects who were first employed in jobs with exposure before the age of 30 years and who were initially exposed at least 30 years prior to diagnosis. These results lend support to the theory that electromagnetic fields may be related to breast cancer in men. The hypothesis warrants evaluation in women.

Objectives: The purpose of this paper was to investigate the relationship between food and beverage consumption and the development of breast cancer in men.Methods: Possible relationships of dietary factors to risk of breast cancer in men were assessed in a case-control study conducted between 1983 and 1986. Cases (N = 220) were ascertained from ten population-based cancer registries. Controls (N = 291) were selected by random-digit dialing (< age 65) and from Health Care Financing Administration Medicare beneficiary lists (> or = age 65).Results: No trends in risk were observed with increasing intakes of specific foods, except for an increase in risk with citrus fruits. No increase in risk with increasing amounts of specific fats, vitamins, or minerals or with amounts of protein, fiber, carbohydrate, starches, nitrites, or alcohol consumed was observed, except for an increase in risk with dietary vitamin C consumption. A decreasing trend in risk with dietary niacin and with coffee and an increasing trend in risk with tea consumption were observed. No associations were found with use of any dietary supplements, including vitamin C.Conclusions: The observed associations are not consistent with findings from studies of breast cancer in women and probably do not represent causal relationships. Dietary factors are unlikely to be strong determinants of breast cancer in men. [ABSTRACT FROM AUTHOR]