Reproductive factors and subtypes of breast cancer defined by hormone receptor and histology.

Reproductive factors are associated with reduced risk of breast cancer, but less is known about whether there is differential protection against subtypes of breast cancer. Assuming reproductive factors act through hormonal mechanisms they should protect predominantly against cancers expressing oestrogen (ER) and progesterone (PR) receptors. We examined the effect of reproductive factors on subgroups of tumours defined by hormone receptor status as well as histology using data from the NIHCD Women's Contraceptive and Reproductive Experiences (CARE) Study, a multicenter case-control study of breast cancer. We estimated odds ratios (ORs) and 95% confidence intervals (CIs) as measures of relative risk using multivariate unconditional logistic regression methods. Multiparity and early age at first birth were associated with reduced relative risk of ER + PR + tumours (P for trend=0.0001 and 0.01, respectively), but not of ER - PR - tumours (P for trend=0.27 and 0.85), whereas duration of breastfeeding was associated with lower relative risk of both receptor-positive (P for trend=0.0002) and receptor-negative tumours (P=0.0004). Our results were consistent across subgroups of women based on age and ethnicity. We found few significant differences by histologic subtype, although the strongest protective effect of multiparity was seen for mixed ductolobular tumours. Our results indicate that parity and age at first birth are associated with reduced risk of receptor-positive tumours only, while lactation is associated with reduced risk of both receptor-positive and -negative tumours. This suggests that parity and lactation act through different mechanisms. This study also suggests that reproductive factors have similar protective effects on breast tumours of lobular and ductal origin.

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.

Comparison of telephone sampling and area sampling: response rates and within-household coverage.

Random digit dialing is used frequently in epidemiologic case-control studies to select population-based controls, even when both cases and controls are interviewed face-to-face. However, concerns persist about the potential biases of random digit dialing, particularly given its generally lower response rates. In an Atlanta, Georgia, case-control study of breast cancer among women aged 20-54 years, all of whom were interviewed face-to-face, two statistically independent control groups were compared: those obtained through random digit dialing (n = 652) and those obtained through area probability sampling (n = 640). The household screening rate was significantly higher for the area sample, by 5.5%. Interview response rates were comparable. The telephone sample estimated a significantly larger percentage (by approximately 7%) of households to have no age-eligible women. Both control groups, appropriately weighted, had characteristics similar to US Census demographic characteristics for Atlanta women, except that respondents in both control groups were more educated and more likely to be married. The authors conclude that households contacted through random digit dialing are somewhat less likely to participate in the household screening process, and if they are cooperative, some households may not disclose that age-eligible women reside therein. Investigators need to develop improved methods for screening and enumerating household members in random digit dialing surveys that target a specific subpopulation, such as women.

Socioeconomic status and multiple myeloma among US blacks and whites.

OBJECTIVES: This study examined the relation between socioeconomic status (SES) and risk of multiple myeloma among Blacks and Whites in the United States. METHODS: This population-based case-control study included 573 cases (206 Blacks and 367 Whites) with new diagnoses of multiple myeloma identified between August 1, 1986, and April 30, 1989, and 2131 controls (967 Blacks and 1164 Whites) from 3 US geographic areas. Information on occupation, income, and education was obtained by personal interview. RESULTS: Inverse gradients in risk were associated with occupation-based SES, income, and education. Risks were significantly elevated for subjects in the lowest categories of occupation-based SES (odds ratio [OR] = 1.71, 95% confidence interval [CI] = 1.16, 2.53), education (OR = 1.36, 95% CI = 1.06, 1.75), and income (OR = 1.43, 95% CI = 1.05, 1.93). Occupation-based low SES accounted for 37% of multiple myeloma in Blacks and 17% in Whites, as well as 49% of the excess incidence in Blacks. Low education and low income accounted for 17% and 28% of the excess incidence in Blacks, respectively. CONCLUSIONS: Our results indicate that the measured SES-related factors account for a substantial amount of the Black-White differential in multiple myeloma incidence.

The positive yield of imaging studies in the evaluation of men with newly diagnosed prostate cancer: a population based analysis.

PURPOSE: We determine the positive yield of imaging studies performed on men with newly diagnosed prostate cancer. MATERIALS AND METHODS: A prospective, population based survey was conducted on 3,690 men with prostate cancer diagnosed between October 1, 1994 and October 31, 1995. Cases were identified by the rapid case ascertainment systems used in 6 geographic regions participating in the Surveillance, Epidemiology and End Results Program. Based on information captured in primary medical record reviews we estimated the positive yield of bone scans, computerized tomography (CT) and magnetic resonance imaging. RESULTS: The positive yield of bone scan and CT was less than 5% and 12%, respectively, for all men with prostate specific antigen (PSA) 4 to 20 ng./ml., and less than 2% and 9%, respectively, for those who also had a Gleason score of 6 or less. Only men with PSA greater than 50 ng./ml. and those with Gleason scores 8 to 10 and PSA greater than 20 ng./ml. had positive yields greater than 10% and 20% for bone scan and CT, respectively. CONCLUSIONS: Imaging studies designed to identify metastases and/or extracapsular extension in men with newly diagnosed prostate cancer frequently have a low positive yield. Wide variations exist in the use of imaging studies and are associated with tumor factors, such as Gleason score and serum PSA, and nontumor factors, such as state of residence. More extensive cost-effectiveness analyses are needed to define appropriate guidelines for ordering imaging studies to optimize the positive yield among men with newly diagnosed prostate cancer.

Occupational risk factors and prostate cancer in U.S. blacks and whites.

Although prostate cancer is a major disease, causal factors are only partially understood. We examined occupational risk factors for this disease in a large case control study among U.S. blacks and whites. The study included 981 new pathologically confirmed prostate cancer cases (479 blacks and 502 whites) diagnosed between 1986 and 1989, and 1,315 population controls (594 blacks and 721 whites) who resided in Atlanta, Detroit, and 10 countries in New Jersey, covered by population-based cancer registries. Information on occupation, including a lifetime work history, was collected by in-person interview. No clear patterns of risk were found for U.S. whites versus blacks, nor for white-collar versus blue-collar jobs. Farming was related to prostate cancer (OR = 2.17; 95% CI = 1.18-3.98). Risk was restricted, however, to short-term workers and workers in crop production. Risk was not limited to those farming after 1950, when widespread use of pesticides started. Risks increased with increasing years of employment in firefighting (chi 2trend, p = 0.02) and power plant operations (chi 2trend, p = 0.03), and were elevated among long-term railroad line-haulers (OR = 5.85; 95% CI = 1.25-27.4); jobs with potential polycyclic aromatic hydrocarbon (PAH) exposures. Risk was elevated among athletes (OR = 5.38; 95% CI = 1.48-19.6). However, most of the cases were athletes before 1960, so the potential use of anabolic steroids was excluded. Although some clues about potential occupational associations were found, the overall results show that occupation is not a major determinant of prostate cancer risk.

Dietary factors and the risk of squamous cell esophageal cancer among black and white men in the United States.

OBJECTIVES: To investigate dietary factors for squamous cell esophageal cancer and whether these factors may contribute to the five-fold higher incidence of this cancer in the black versus white population of the United States. METHODS: Data from a food frequency questionnaire were analyzed for 114 white men and 219 black men with squamous cell esophageal cancer, and 681 white and 557 black male controls from three areas of the United States who participated in a population-based case-control study of esophageal cancer. RESULTS: Protective effects were associated with intake of raw fruits and vegetables (odds ratio for high versus low consumers = 0.3 in both white and black men) and use of vitamin supplements (especially vitamin C; odds ratio for high versus low consumers = 0.4 in both races), with the frequency of consumption of raw fruits and vegetables and vitamin supplements being greater for white than black controls. In addition, elevated risks were associated with high versus low intake of red meat (OR = 2.7 for blacks and 1.5 for whites) and processed meat (OR = 1.6 for blacks and 1.7 for whites), with the levels of consumption being greater for black than white controls. CONCLUSIONS: In the United States, these dietary factors may contribute in part to the much higher incidence of squamous cell esophageal cancer among black compared to white men.

Drinking practices and risk of squamous-cell esophageal cancer among Black and White men in the United States.

To evaluate whether the fivefold greater incidence rate of squamous-cell esophageal cancer in Black compared with White men is due to type of alcoholic beverage consumed or to other qualitative differences in alcohol consumption, we conducted a population-based case-control study with 373 males diagnosed with squamous-cell esophageal cancer (124 Whites and 249 Blacks) and 1,364 male controls (750 Whites and 614 Blacks) from three geographic areas in the United States. Included were all histologically confirmed cases newly diagnosed from 1 August 1986 through 30 April 1989, among White and Black men aged 30 to 79 years. Risks varied to some extent according to type of alcohol used, with beer a stronger contributor in Whites, and wine and liquor stronger contributors in Blacks. However, most of the differences in the odds ratios by type of alcohol and race were eliminated after controlling for average weekly amount of total alcohol consumed. Thus, while alcohol use in all forms is an important risk factor for squamous-cell esophageal cancer in Whites and Blacks, type of alcoholic beverage used does not appear to account for the racial differences in incidence.

Multiple myeloma among Blacks and Whites in the United States: role of cigarettes and alcoholic beverages.

In the United States, the incidence rates of multiple myeloma in Blacks are more than twice those in Whites, but the etiology of this cancer is poorly understood. A population-based case-control interview study of 571 subjects (365 White, 206 Black) with multiple myeloma and 2,122 controls (1,155 White, 967 Black) living in three areas of the United States (Georgia, Michigan, New Jersey) offered the opportunity to investigate the relationship with smoking and alcohol drinking and to evaluate whether these factors might contribute to the excess risk of multiple myeloma in Blacks. For Blacks and Whites of either gender, there were no significantly elevated risks associated with ever use of cigarettes or alcoholic beverages and no consistent patterns with either intensity or duration of use. These data support previous studies indicating that smoking and drinking are not related causally to the risk of multiple myeloma, and thus cannot account for the racial disparity in incidence rates.

Effect of a cancer screening intervention conducted by lay health workers among inner-city women.

INTRODUCTION: We conducted a randomized controlled trial to determine if an in-home educational intervention conducted by lay health workers (LHWs) could increase adherence among low-income, inner-city, African-American women to breast and cervical cancer screening schedules. METHODS: We recruited 321 African-American women from diverse inner-city sources. After baseline interviews, they were randomly assigned to either the intervention (n = 163) or the control (n = 158) group. Those in the intervention group were visited in their homes up to three times by LHWs who provided a culturally sensitive educational program that emphasized the need for screening. RESULTS: Ninety-three (93) women in the intervention group and 102 in the control group completed the postintervention interview. For Pap smears, the increase in screening was similar in both groups. For clinical breast exams (CBEs), however, there was a modest increase in the intervention group. The improvement was greatest for mammography, for which there was a 10% to 12% increase. Among women who were not on recommended schedules at baseline, the improvement was substantial and greater in the intervention group. CONCLUSIONS: LHWs' intervention appeared to improve the rate at which inner-city women obtained CBEs and mammograms, but had no effect on Pap smears. A high attrition rate weakened our ability to make conclusive statements about the exact impact of the intervention.

Alcohol use and prostate cancer risk in US blacks and whites.

Prostate cancer is the most common malignancy in US men (more than 165,000 cases per annum) and occurs substantially more frequently in blacks than in whites. The causes of this disease are, however, poorly understood. Alcohol consumption, which has been clearly related to malignancies of the upper aerodigestive tract, may also increase risk of cancer at other sites, including the prostate. The authors investigated alcohol use as a risk factor for prostate cancer among US blacks and whites. A population-based, case-control study was carried out among 981 men (479 blacks and 502 whites) with pathologically confirmed prostate cancer diagnosed between August 1, 1986, and April 30, 1989, and 1,315 controls (594 blacks and 721 whites) who resided in Atlanta, Georgia; Detroit, Michigan; and 10 counties in New Jersey, geographic areas covered by three population-based cancer registries. In-person interviews elicited information on alcohol use and other factors possibly related to prostate cancer. Compared with never-users, risk for prostate cancer increased with amount of alcohol drunk (chi2 (trend), p < 0.001), with significantly elevated risks seen for those who had 22-56 drinks per week (odds ratio = 1.4; 95% confidence interval 1.0-1.8) and 57 or more drinks per week (odds ratio = 1.9; 95% confidence interval 1.3-2.7). The finding was consistent among blacks (chi2 (trend), p < 0.01) and whites (chi2 (trend), p < 0.05), and among young and old subjects; it was not restricted to a specific type of alcoholic beverage. In this first large study among US blacks and whites, increased risk for prostate cancer was associated with increased alcohol use. The risk was similar for whites and blacks and could not be attributed to tobacco use or to a number of other potential confounders.

Exogenous sex hormone use, correlates of endogenous hormone levels, and the incidence of histologic types of sarcoma of the uterus.

BACKGROUND: We analyzed data from a population-based, multi-center, case-control study to determine whether the occurrence of histologic types of uterine sarcoma is related to exogenous hormone use and/or to two correlates of endogenous estrogens: excess weight and cigarette smoking. METHODS: One hundred sixty-seven women with newly-diagnosed uterine sarcoma (56 leiomyosarcoma, 85 mixed mullerian tumors, and 26 endometrial stromal sarcomas) were interviewed by telephone regarding possible risk factors for these neoplasms, For comparison, 208 women identified at random from the general population of the study areas were interviewed as controls. RESULTS: Use of oral contraceptives was positively associated with the risk of leiomyosarcoma (odds ratios [OR] = 1.7, 95% confidence interval [CI] = 0.7, 4.1), primarily among women who last used these medications 15 or more years prior to diagnosis. Use of noncontraceptive estrogens was directly associated with the risk of mixed mullerian tumors, but only among recent and long-term users of these medications. Women in the highest quantile of body mass index (> or = 27.5 kg/m2) one year prior to diagnosis were at increased risk of each type of uterine sarcoma (leiomyosarcoma, OR = 2.5, 95% CI = 1.1, 5.7; mixed mullerian tumors, OR = 2.9, 95% CI = 1.3, 6.7; stromal sarcoma, OR = 3.5, 95% CI = 1.1, 10.9). Women who had ever smoked cigarettes were at reduced risk of leiomyosarcoma (OR = 0.6, 95% CI = 0.3, 1.1) and stromal sarcoma (OR = 0.5, 95% CI = 0.2, 1.2), but the relationship was not more pronounced among heavy smokers; no association with smoking was observed with mixed mullerian tumors. CONCLUSIONS: Several of these findings parallel those from studies of endometrial carcinoma and may indicate a role for unopposed estrogen in the etiology of histologic types of uterine sarcoma.

Oral contraceptives and breast cancer risk among younger women.

BACKGROUND: Several studies have suggested a link between oral contraceptive use and breast cancer in younger women, but it is possible that chance or bias, including selective screening of contraceptive users, contributed to the putative association. PURPOSE: Given that oral contraceptives were first marketed in the United States in the early 1960s, we conducted a population-based case-control study to examine the relationship between use of oral contraceptives and breast cancer among women in a recently assembled cohort, focusing on women younger than 45 years of age who had the opportunity for exposure throughout their entire reproductive years. METHODS: Breast cancer patients and healthy control subjects were identified, the latter group by random-digit dialing, in Atlanta, Ga., Seattle/Puget Sound, Wash., and central New Jersey. In Seattle and New Jersey, the study was confined to women 20 through 44 years of age; in Atlanta the age range was extended through 54 years. Patients included women with in situ or invasive breast cancer newly diagnosed during the period of May 1, 1990, through December 31, 1992. In-person interviews were completed by 2203 (86.4%) of 2551 eligible patients and 2009 (78.1%) of 2571 eligible control subjects. Analyses focused on women younger than 45 years of age (1648 patients and 1505 control subjects) to maximize opportunities for extended exposure. Logistic regression analyses were used to obtain maximum likelihood estimates of relative risks (RRs) and their 95% confidence intervals (CIs). RESULTS: Among women younger than 45 years, oral contraceptive use for 6 months or longer was associated with an RR for breast cancer of 1.3 (95% CI = 1.1-1.5). Risks were enhanced for breast cancers occurring prior to age 35 years (RR = 1.7; 95% CI = 1.2-2.6), with the RR rising to 2.2 (95% CI = 1.2-4.1) for users of 10 or more years. The RR for breast cancer for those whose oral contraceptive use began early (before age 18 years) and continued long-term (> 10 years) was even higher (RR = 3.1; 95% CI = 1.4-6.7). The RRs observed for those who used oral contraceptives within 5 years of cancer diagnosis were higher than for those who had not, with the effect most marked for women younger than age 35 years (RR = 2.0; 95% CI = 1.3-3.1). Oral contraceptive associations were also strongest for cancers diagnosed at advanced stages. Evaluation of screening histories and methods of diagnosis failed to support the speculation that associations could be due to selective screening. Among women 45 years of age and older, no associations of risk with use of oral contraceptives were noted. CONCLUSIONS: The relationship between oral contraceptives and breast cancer in young women appears to have a biologic basis rather than to be an artifact or the result of bias.

PIP: A population-based case control study examined the relationship between use of oral contraceptives and breast cancer among women in a cohort, focusing on women younger than 45 years old who had the opportunity for exposure throughout their entire reproductive years. Breast cancer patients and healthy control subjects were identified, the latter group by random-digit dialing, in Atlanta, Georgia, Seattle/Puget Sound, Washington, and central New Jersey. In Seattle and New Jersey, the study was confined to women 20-44 years old; in Atlanta the age range was extended through 54 years. Patients included women with in situ or invasive breast cancer newly diagnosed during the period of May 1, 1990, through December 31, 1992. In-person interviews were completed by 2203 (86.4%) of 2551 eligible patients and 2009 (78.1%) of 2571 eligible control subjects. Analyses focused on women younger than 45 years old (1648 patients and 1505 control subjects) to maximize opportunities for extended exposure. Logistic regression analyses were used to obtain maximum likelihood estimates of relative risks (RRs). Among women under 45, oral contraceptive use for 6 months or longer was associated with an RR for breast cancer of 1.3. Risks were enhanced for breast cancers occurring prior to age 35 years (RR = 1.7) with the RR rising to 2.2 for users of 10 or more years. The RR for breast cancer for those whose oral contraceptive use began before age 18 years and continued long-term ( 10 years) was even higher (RR = 3.1). The RRs observed for those who used oral contraceptives within 5 years of cancer diagnosis were higher than for those who had not, with the effect most marked for women younger than 35 years (RR = 2.0). Oral contraceptive associations were also strongest for cancers diagnosed at advanced stages. The relationship between oral contraceptives and breast cancer in young women appears to have a biologic basis rather than to be an artifact or the result of bias.

Prostate cancer risk in U.S. blacks and whites with a family history of cancer.

Prostate cancer occurs more frequently in U.S. blacks than whites. A population-based case-control study which investigated the association with family history of cancer was carried out among 981 men (479 black, 502 white) with pathologically confirmed prostate cancer, diagnosed between August 1, 1986, and April 30, 1989, and 1,315 controls (594 black, 721 white). Study subjects, aged 40-79, resided in Atlanta, Detroit, and 10 counties in New Jersey, geographic areas covered by population-based cancer registries. Prostate cancer risk was significantly elevated among those who reported a history of prostate cancer in first-degree relatives (O.R. = 3.2; 95% C.I.: 2.0-5.0), with blacks and whites having similarly elevated risks. These risks were unchanged by statistical adjustment for job-related socio-economic status, education, income, and marital status. Overall, the ORs associated with history of prostate cancer in fathers and brothers were 2.5 (95% C.I.: 1.5-4.2) and 5.3 (95% C.I.: 2.3-12.5), respectively. Risks associated with a family history of prostate cancer were consistently elevated among younger and older subjects. Only small non-significant excesses of prostate cancer risk were associated with a family history of breast, colorectal, or other cancers. While familial occurrence is a key risk factor for prostate cancer and likely to be genetically based, the similar familial risks among blacks and whites suggest that the ethnic disparity in incidence is influenced by environmental factors.

Multiple myeloma among blacks and whites in the United States: the role of chronic antigenic stimulation.

Multiple myeloma (MM) is twice as common among Blacks than Whites in the United States. The reasons for this racial disparity are unknown, and the etiology of this cancer, in general, is poorly understood. Repeated or chronic antigenic stimulation (CAS) of the immune system has been suggested as a risk factor. Previous case-control studies have reported inconsistent CAS associations based on evaluations of individual and biologic categories of medical conditions. Interview data from 573 cases and 2,131 population-based controls were used to investigate further the CAS hypothesis using an immunologically based approach, and to determine whether CAS accounts for the excess of myeloma among Blacks. Over 50 medical conditions were grouped into biologically and immunologically related categories, and B-cell- and T-cell-mediated response groups. Except for urinary tract infections among Black men (odds ratio [OR] = 2.0), no significantly increased risks of MM were observed. However, there was a suggestion of increased risk among Blacks with an increased exposure to anaphylactic conditions. Analysis by immunoglobulin type revealed significantly elevated risks of IgG myeloma with eczema (OR = 2.1), the biologic category 'allergic conditions' (OR = 1.6), and the immunologic category 'anaphylaxis response' (OR = 1.6) among Whites, with Blacks having slightly lower risks. Our findings do not support a causal relationship between CAS and MM, nor do they explain the higher incidence among Blacks.

Second cancers following oral and pharyngeal cancer: patients' characteristics and survival patterns.

A survey was made of second primary cancers among patients who were enrolled in a large case-control investigation of oral and pharyngeal cancer, hereafter called oral cancer, during 1984-1985 in four areas of the United States. Among the original 1090 patients with oral cancer (nearly all squamous cell carcinomas), 107 developed a second cancer (one-half of them squamous cell) by the end of follow-up in June 1989 (average follow-up 2.6 years), with 69% occurring in the oral cavity, pharynx, oesophagus, larynx or lung. Rates of second tumours varied by age and socioeconomic status, but not sex or race, and were higher among those whose initial cancer was localised, even after adjusting for their longer survival. Long-term survival was lower among those with second cancers. Conditional on surviving for 2 years, the survival at 5 years was under 50% and nearly 70%, respectively, for those with versus those without a second cancer in the first 2 years. These findings confirm the exceptionally high rate of second cancers (especially of the aerodigestive tract) following oral cancer, describe the clinical and pathological features of patients with multiple cancers and indicate the importance of preventive measures.

Are racial differences in squamous cell esophageal cancer explained by alcohol and tobacco use?

BACKGROUND: In the United States, incidence rates of squamous cell esophageal cancer are more than five times higher among black men than among white men. Reasons that might explain this large racial disparity are being sought. PURPOSE: We evaluated whether differential use of alcohol and tobacco can fully account for the excess of squamous cell esophageal cancer among U.S. blacks. METHODS: We conducted a population-based, case-control study with in-person interviews with 373 squamous cell esophageal cancer case patients (124 white males and 249 black males) and 1364 control subjects (750 white males and 614 black males) from three U.S. geographic areas. Histologically confirmed cases of squamous cell esophageal cancer newly diagnosed from August 1, 1986, through April 30, 1989, among white and black men aged 30-79 years were included. RESULTS: Alcohol use of more than one drink per day and/or current cigarette use of at least one pack per day accounted for 92.7% (95% confidence interval [CI] = 86.8%-98.5%) of the squamous cell esophageal cancers in blacks, versus 86.3% (95% CI = 75.5%-97.1%) in whites, and for 94% of the difference between the black and white annual incidence rates. The interaction between race and the continuous drinking/smoking variable in a logistic regression analysis was statistically significant (two-sided, P = .02). Exposure rates among controls at all levels of combined alcohol and tobacco use examined were slightly higher among blacks and accounted for a small portion of the racial differences in incidence rates. CONCLUSION: Although the vast majority of esophageal cancers in both blacks and whites in our data can be explained by use of alcohol and tobacco, it is not clear why heavy consumption of alcohol and/or tobacco is responsible for 14.9 per 100,000 per year more cases of squamous cell esophageal cancer among blacks than among whites. The differences in the odds ratios appear to account for more of the racial differences in incidence rates than do the prevalences of exposure to alcohol and tobacco alone. The reasons for this apparent racial difference in carcinogenic risk from the same level of alcohol and tobacco use are unknown, but they may include qualitative differences in alcohol consumption, differences in other environmental exposures that interact with alcohol and/or tobacco to modify risks, or differences in susceptibility to these factors.

Adenocarcinoma of the esophagus and esophagogastric junction in white men in the United States: alcohol, tobacco, and socioeconomic factors.

In the United States, the incidence of adenocarcinoma of the esophagus, including the esophagogastric (EG) junction, has been increasing rapidly over the past two decades. Except for an association with Barrett's esophagus, little is known about the etiology of these cancers. A population-based case-control interview study of 174 White men with adenocarcinoma of the esophagus and 750 controls living in three areas of the United States offered the opportunity to investigate the relationship of these cancers with smoking, alcohol drinking, socioeconomic factors, and history of ulcer. There were significantly elevated risks for men who smoked cigarettes (odds ratio [OR] = 2.1) or drank liquor (OR = 1.6). For both cigarette smoking and liquor drinking, there were significant dose gradients with amount consumed. No reduction in risk was observed following smoking cessation. Subjects who switched from nonfilter to filter cigarettes experienced half the risk of those who only smoked nonfilter cigarettes. Inverse risk gradients were seen with increasing recent annual income, with the highest risk (OR = 3.4) for the lowest category. The risk for a history of ulcer (OR = 1.7), especially of the duodenum (OR = 2.2), was also significantly elevated. These data suggest that tobacco and alcohol may be etiologic factors for adenocarcinoma of the esophagus and EG junction, but these factors do not appear to explain the rapid rise in incidence of these tumors. The associations with low social class and history of ulcer need to be explored in greater detail along with other factors that may account for the temporal trends in esophageal adenocarcinomas.

Tobacco use and prostate cancer in blacks and whites in the United States.

Prostate cancer occurs more frequently in Blacks than Whites in the United States. A population-based case-control study which investigated the association between tobacco use and prostate cancer risk was carried out among 981 pathologically confirmed cases (479 Blacks, 502 Whites) of prostate cancer, diagnosed between 1 August 1986 and 30 April 1989, and 1,315 controls (594 Blacks, 721 Whites). Study subjects, aged 40 to 79 years, resided in Atlanta (GA), Detroit (MI), and 10 counties in New Jersey, geographic areas covered by three, population-based, cancer registries. No excesses in risk for prostate cancer were seen for former cigarette smokers, in Blacks (odds ratio [OR] = 1.1, 95 percent confidence interval [CI] = 0.7-1.5) and in Whites (OR = 1.2, CI = 0.9-1.6), or for current cigarette smokers, in Blacks (OR = 1.0, CI = 0.7-1.4) and in Whites (OR = 1.2, CI = 0.8-1.7). Increases in risk were noted for smokers of 40 or more cigarettes per day, among former (OR = 1.4, CI = 1.0-1.5) and current (OR = 1.5, CI = 1.0-2.4) smokers. Duration of cigarette use and cumulative amount of cigarette use (pack-years) were not associated with prostate cancer risk for Blacks or Whites. By age, only the youngest subjects, aged 40 to 59 years, showed excess risk associated with current (OR = 1.5, CI = 1.0-2.3) and former (OR = 1.7, CI = 1.1-2.6) use of cigarettes, but there were no consistent patterns in this group according to amount or duration of smoking.(ABSTRACT TRUNCATED AT 250 WORDS)