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Steroid 5-alpha-reductase type 2 (SRD5a2) is a critical enzyme in androgen metabolism. Two polymorphisms in the SRD5a2 gene, V89L (rs523349) and A49T (rs9282858), have been studied for associations with prostate cancer risk, with conflicting results. The authors conducted a systematic review and meta-analysis (1997-2007) to examine these associations and compared the results with findings from genome-wide association studies of prostate cancer. The meta-analysis included 24 case-control studies (10,088 cases and 10,120 controls for V89L and 4,998 cases and 5,451 controls for A49T). The authors found that prostate cancer was not associated with V89L (L allele vs. V allele: odds ratio = 0.99, 95% confidence interval: 0.94, 1.05) and was probably not associated with A49T (T allele vs. A allele: odds ratio = 1.10, 95% confidence interval: 0.86, 1.40). These results could have been distorted by spectrum-of-disease bias, convenience sampling of cases and controls, genotype misclassification, and/or confounding. Neither V89L nor A49T was included in microarray chips used for published genome-wide association studies. Analysis of well-designed population-based studies with pathway-based arrays containing common genetic variants could be useful for identifying genetic factors in prostate cancer. [ABSTRACT FROM AUTHOR]

Data on 1,501 control women from a multi-center, population-based, case-control study of breast cancer were used to examine characteristics associated with recreational exercise during the year prior to the interview among women 20 to 44 years of age. In a univariate analysis, higher levels of recreational exercise were associated with: higher education; higher family income; white race; previous participation in recreational exercise above the median level at ages 12 to 13 and at age 20; being nulliparous; ever lactating; being a never or past smoker; having a low current Quetelet's index (QI: weight in kilograms divided by height in meters squared); and living in Atlanta or Seattle (compared to New Jersey). 1n a multiple linear regression model, independent predictors of higher levels of recreational exercise were: participation in higher levels of exercise at 20 years of age; having a low current QI; and never having smoked. Though all women should be encouraged to participate in exercise, these findings identity subgroups of women that may need targeting when developing exercise intervention programs. [ABSTRACT FROM AUTHOR]

This randomized clinical trial examined the feasibility of low-fat dietary interventions among postmenopausal women of diverse backgrounds. During 1992-1994, 2,208 women aged 50-79 years, 28% of whom were black and 16% Hispanic, enrolled at clinics in Atlanta, Georgia, Birmingham, Alabama, and Miami, Florida. Intervention/support groups met periodically with a nutritionist to reduce fat intake to 20% of energy and to make other diet modifications. At 6 months postrandomization, the intervention group reduced fat intake from 39.7% of energy at baseline to 26.4%, a reduction of 13.3% of energy, compared with 2.3% among controls. Saturated fatty acid and cholesterol intakes were reduced, but intakes of fruits and vegetables, but not grain products, increased. Similar effects were observed at 12 and 18 months. Black and non-Hispanic white women had similar levels of reduction in fat, but the decrease in Hispanic women was less. Changes did not vary significantly by education. While bias in self-reported intakes may have resulted in somewhat overestimated changes in fat intake, the reported reduction was similar to the approximately 10% of energy decrease found in most trials and suggests that large changes in fat consumption can be attained in diverse study populations and in many subgroups. [ABSTRACT FROM AUTHOR]

Background: Several common medical conditions are associated with altered hormone levels, and may thus plausibly influence breast cancer risk. Few studies have examined such relationships, and we utilized a population-based case-control study of young women in the US to examine breast cancer risk following a history of various medical conditions. Relationships between breast cancer and each medical condition examined are biologically plausible, and relevant in terms of public health.Methods: The study included 2173 breast cancer cases and 1990 population-based controls from three areas of the US, under 55 years, who were administered a questionnaire including details of physician-diagnosed medical conditions.Results: No significantly increased or decreased breast cancer risk was associated with a history of thyroid disease, gallbladder disease, colorectal polyps, diabetes, high blood pressure, high cholesterol or surgery for endometriosis. There was some evidence of an increased breast cancer risk associated with ovarian cysts among women who did not receive an oophorectomy (relative risk [RR] = 1.94, 95% CI: 1.0-3.9). Non-significant increases in breast cancer risk were observed following diagnoses of several other cancers, including thyroid cancer, basal cell carcinoma, Hodgkin's disease and malignant melanoma.Conclusions: To conclude, our generally null results from this large, population-based study support results from previous studies in providing reassurance that women with a history of several common medical conditions do not appear to be at an increased risk of breast cancer at a young age. [ABSTRACT FROM AUTHOR]

Background: Blacks have lower survival rates for colon cancer than whites, possibly related to more advanced stages of disease at diagnosis and to socioeconomic differences between blacks and whites. While the black/white difference in colon cancer survival is well documented, the few studies that have investigated this difference have been limited by the modest number and type of explanatory factors that were considered.Purpose: We analyzed data from the National Cancer Institute Black/White Cancer Survival Study to determine 1) what characteristics might contribute to the racial difference in colon cancer survival and 2) if a survival disparity remained between black and white patients after adjustment was made for these characteristics.Methods: This prospective study included 454 blacks and a stratified random sample of 521 whites, aged 20-79 years, with cancer of the colon diagnosed from January 1, 1985, through December 31, 1986, and who were residents of the metropolitan areas of Atlanta, New Orleans, and San Francisco/Oakland. Follow-up was truncated on December 31, 1990. Cox proportional hazards regression was used to estimate the death rate among blacks relative to that among whites after adjustment for potential explanatory factors, including sociodemographic factors, concurrent (comorbid) medical conditions, stage at diagnosis, tumor characteristics, and treatment. All P values were calculated from two-tailed tests of statistical significance.Results: After adjustment for age, sex, and geographic area, the black-to-white mortality hazard ratio (HR) was 1.5 (95% confidence interval [CI] = 1.2-1.9), indicating that the risk of death among black patients was 50% higher than that among white patients. Further adjustment for stage reduced the excess cancer mortality to 20% (HR = 1.2; 95% CI = 1.0-1.5), decreasing the overall racial difference in excess mortality from 50% to 20% or to a 60% reduction in excess mortality. Although adjustment for poverty reduced the excess mortality by 20%, adjusting for both stage and poverty did not further reduce the racial difference. Among patients with stages II and III disease, blacks had lower survival rates than whites (HR = 1.8; 95% CI = 1.0-3.1 and HR - 1.5; 95% CI = 1.0-2.3, respectively). Among those patients with metastatic disease (stage IV), survival was similar for whites and blacks.Conclusions: Stage at diagnosis accounted for more than half of the excess colon cancer mortality observed among blacks. Poverty and other socioeconomic conditions, general health status, tumor characteristics, and general patterns of treatment did not further explain the remaining survival disadvantage among blacks.Implications: Because the racial disparity was confined to earlier stages, future studies should investigate whether blacks have more advanced disease at diagnosis and whether less aggressive treatment is provided because of understanding. [ABSTRACT FROM AUTHOR]

This experimental study attempts to determine if an in-home educational intervention conducted by lay health workers (LHWs) can increase adherence among low-income, inner-city black women to schedules for screening for breast cancer and cervical cancer, as well as increase the women's knowledge and change their attitudes regarding these cancers. This paper is a description of the purposes, hypotheses, design, subject recruitment, intervention, and evaluation of the study conducted by Morehouse School of Medicine. Subjects were recruited from a variety of sources, including patients seen in a community health center, women referred by the National Black Women's Health Project (NBWHP), residents of public and senior citizen housing projects, and persons identified in various community settings. Fewer than half of those asked to participate agreed to do so. The 321 women who were recruited were demographically diverse. Overall, about half of these volunteer subjects self-reported at least one Papanicolaou (Pap) smear and one breast examination within a year before enrollment in the study. There was little variation by source of recruitment in compliance with screening recommendations, except that referrals from NBWHP were more likely (P < 0.01) to have had a Pap test and breast self-examination, while residents of public housing projects were somewhat less likely to have done so. About 35 percent of participants ages 35 and older had a mammogram within an appropriate interval. Participants were randomly assigned to intervention and control groups. Women in the intervention group were visited in their homes by LHWs on three occasions; the LHWs provided education on cancer and reproductive health. The groups were comparable in their baseline sociodemographic status and previous screening history. [ABSTRACT FROM AUTHOR]

Objective: To examine the ability of recognized prognostic factors for breast cancer to account for the observed poorer survival in blacks compared with their white counterparts.Design and Participants: Subjects included 1130 women (612 blacks and 518 whites) aged 20 to 79 years residing in metropolitan Atlanta, Ga, New Orleans, La, or San Francisco/Oakland, Calif, who were diagnosed with primary invasive breast cancer. Information on stage, tumor characteristics, treatment, comorbid conditions, and sociodemographic factors was obtained from personal interview, physician and hospital records, and a pathology review of biopsy and surgical specimens.Main Outcome Measure: Multivariable survival models were used to estimate the hazard ratio (relative risk of mortality) for blacks compared with whites, adjusting for various combinations of potential explanatory factors.Results: After controlling for geographic site and age, the risk of dying was 2.2 times (95% confidence interval [CI], 1.8 to 2.8) greater for blacks than whites. Adjustment for stage reduced the risk from 2.2 to 1.7; further adjustment for sociodemographic variables had no effect. Treatment was not a contributing factor once stage and tumor pathology were in the model. After adjusting for stage, treatment, comorbid illness, and pathologic and sociodemographic variables, blacks continued to demonstrate a slightly increased, but not statistically significant, risk of death (hazard ratio = 1.3; 95% CI, 1.0 to 1.8). Results were similar for all-cause mortality and breast cancer-specific mortality.Conclusions: Approximately 75% of the racial difference in survival was explained by the prognostic factors studied. Sociodemographic variables appeared to act largely through racial differences in stage at diagnosis, which may be amenable to change through improved access to and use of screening for black women. [ABSTRACT FROM AUTHOR]

This report describes the associations of race/ethnicity and years of education with the validity, reliability, and bias of a self-administered food frequency questionnaire (FFQ) designed to be sensitive to low-fat, regional, and ethnic dietary patterns. Data were from the Women's Health Trial Feasibility Study in Minority Populations, a randomized clinical trial conducted between 1992 and 1994 to test the feasibility of a low-fat dietary intervention that targeted low-income, black, and Hispanic women. Of 1,015 participants eligible for these analyses, 28.1% were black, 16.2% were Hispanic, and 12.3% had not completed high school. The analyses focused on percentage of energy obtained from fat, and used 4-day food records as the criterion instrument. Validity at baseline, defined as the correlation between FFQs and food records, was lower among blacks than among whites (0.26 vs. 0.49; p < 0.001), did not differ between Hispanics and whites, and was lower among women with fewer years of education (0.19, 0.35, 0.49, and 0.42 for <12, 12, 13-15, and > or =16 years of education, respectively; for trend, p < 0.05). Six months after randomization, validity increased in most race/ethnicity and education subgroups, and differences across groups became small and statistically nonsignificant. Validity increased significantly among participants receiving the dietary intervention, while increases among control women were somewhat smaller. Reliability, defined as the correlation between baseline and 6-month measures among controls, was similar across racial/ethnic and educational groups. Bias at baseline, defined as the mean value from the FFQ minus the mean from the food record, was 4.6 percentage points of energy from fat; it was lowest among blacks (p < 0.01) and did not differ by years of education. These results suggest that special protocols which address participant training may be necessary when using self-administered FFQs in minority or poorly educated populations. [ABSTRACT FROM AUTHOR]

To assess the performance of food-frequency questionnaires in minority populations, we reviewed published studies of such questionnaires with respect to reports of reliability, bias in mean intake estimates, validity, and factors that might affect these characteristics, including the method by which a questionnaire was developed. Because of the small number of studies and the variation in their methods, the results of the review are not easily summarized and cannot be generalized. Most reliability correlation coefficients were in the range usually reported in evaluations of the performance of questionnaires in nonminority populations (0.5-0.8). Mean intakes derived from questionnaires were generally higher than those estimated with use of referent methods, although this varied according to the population, questionnaire, and nutrient being assessed; moreover, the accuracy of the referent method was questioned by some investigators. Validation correlation coefficients were variable, with some indicating that the questionnaires performed less well in certain populations. Additional research is needed on the performance of food-frequency questionnaires in minority and multicultural populations and on determining how best to develop such questionnaires. (C) 1997 American Society for Clinical Nutrition [ABSTRACT FROM AUTHOR]

Most major medical organizations recommend routine screening for breast, cervical, and colorectal cancers. Screening can lead to early detection of these cancers, resulting in reduced mortality. Yet not all people who should be screened are screened, either regularly or, in some cases, ever. This report presents the results of systematic reviews of effectiveness, applicability, economic efficiency, barriers to implementation, and other harms or benefits of interventions designed to increase screening for breast, cervical, and colorectal cancers by increasing community access to these services. Evidence from these reviews indicates that screening for breast cancer (by mammography) has been increased effectively by reducing structural barriers and by reducing out-of pocket client costs, and that screening for colorectal cancer (by fecal occult blood test) has been increased effectively by reducing structural barriers. Additional research is needed to determine whether screening for cervical cancer (by Pap test) can be increased by reducing structural barriers and by reducing out-of-pocket costs, whether screening for colorectal cancer (fecal occult blood test) can be increased by reducing out-of-pocket costs, and whether these interventions are effective in increasing the use of other colorectal cancer screening procedures (i.e., flexible sigmoidoscopy, colonoscopy, double contrast barium enema). Specific areas for further research are also suggested in this report. [ABSTRACT FROM AUTHOR]

Purpose: This paper presents methods and operational results of a population-based case-control study examining the effects of oral contraceptive use on breast cancer risk among white and black women aged 35-64 years in five U.S. locations.Methods: Cases were women newly diagnosed with breast cancer during July 1994 through April 1998. Controls were identified through random digit dialing (RDD) using unclustered sampling with automated elimination of nonworking numbers. Sampling was density-based, with oversampling of black women. In-person interviews were conducted from August 1994 through December 1998. Blood samples were obtained from subsets of cases and controls, and tissue samples were obtained from subsets of cases. A computerized system tracked subjects through study activities. Special attention was devoted to minimizing exposure misclassification, because any exposure-disease associations were expected to be small.Results: An estimated 82% of households were screened successfully through RDD. Interviews were completed for 4575 cases (2953 whites; 1622 blacks) and 4682 controls (3021 whites; 1661 blacks). Interview response rates for cases and controls were 76.5% and 78.6%, respectively, with lower rates for black women and older women.Conclusions: The methodologic details of this large collaboration may assist researchers conducting similar investigations. [ABSTRACT FROM AUTHOR]

Most major medical organizations recommend routine screening for breast, cervical, and colorectal cancers. Screening can lead to early detection of these cancers, resulting in reduced mortality. Yet not all people who should be screened are screened, either regularly or, in some cases, ever. This report presents the results of systematic reviews of effectiveness, applicability, economic efficiency, barriers to implementation, and other harms or benefits of interventions designed to increase screening for breast, cervical, and colorectal cancers by increasing community demand for these services. Evidence from these reviews indicates that screening for breast cancer (mammography) and cervical cancer (Pap test) has been effectively increased by use of client reminders, small media, and one-on-one education. Screening for colorectal cancer by fecal occult blood test has been increased effectively by use of client reminders and small media. Additional research is needed to determine whether client incentives, group education, and mass media are effective in increasing use of any of the three screening tests; whether one-on-one education increases screening for colorectal cancer; and whether any demand-enhancing interventions are effective in increasing the use of other colorectal cancer screening procedures (i.e., flexible sigmoidoscopy, colonoscopy, double contrast barium enema). Specific areas for further research are also suggested in this report. [ABSTRACT FROM AUTHOR]