Physical Exercise and Reduced Risk of Breast Cancer in Young WomenLeslie Bernstein, Brian E. Henderson, Rosemarie Hanisch et al.|JNCI Journal of the National Cancer Institute|1994 BACKGROUND: Epidemiologic evidence strongly suggests that cumulative exposure to ovarian hormones is a determinant of breast cancer risk. Because physical activity can modify menstrual cycle patterns and alter the production of ovarian hormones, it may reduce breast cancer risk; yet few epidemiologic studies have assessed this relationship. PURPOSE: The major objective of this study was to determine whether young women (aged 40 and younger) who regularly participated in physical exercise activities during their reproductive years had a reduced risk of breast cancer. METHODS: Using a case-control design, we conducted personal interviews of a total of 545 women (aged 40 and younger at diagnosis) who had been newly diagnosed with in situ or invasive breast cancer between July 1, 1983, and January 1, 1989, and a total of 545 control subjects. Case patients and control subjects were individually matched on date of birth (within 36 months), race (white), parity (nulliparous versus parous), and neighborhood of residence. Lifetime histories of participation in physical exercise activities on a regular basis were obtained during the personal interview. RESULTS: After adjustment for potential confounding factors, we found that the average number of hours spent in physical exercise activities per week from menarche to 1 year prior to the case patient's diagnosis was a significant predictor of reduced breast cancer risk (two-sided P for trend < .0001). The odds ratio (OR) of breast cancer among women who, on average, spent 3.8 or more hours per week participating in physical exercise activities was 0.42 (95% confidence limits [CLs] = 0.27, 0.64) relative to inactive women. The effect was stronger among women who had had a full-term pregnancy. Comparing most active (> or = 3.8 hours/wk of exercise) women to inactive women, the ORs were 0.28 (95% CL = 0.16, 0.50) for parous and 0.73 (95% CL = 0.38, 1.41) for nulliparous women. CONCLUSIONS: Most previously identified risk factors for breast cancer are reproductive and menstrual events that cannot be readily altered. The protective effect of exercise on breast cancer risk in the women whom we studied suggests that physical activity offers one modifiable lifestyle characteristic that may substantially reduce a woman's lifetime risk of breast cancer. IMPLICATIONS: Whether the protective effects of exercise on breast cancer risk are due to alterations in ovarian function and whether they extend into women's menopausal years need to be established. Our results suggest that implementation of regular physical exercise programs as a critical component of a healthy lifestyle should be a high priority for adolescent and adult women.
Diagnostic Evaluation of HER-2 as a Molecular Target: An Assessment of Accuracy and Reproducibility of Laboratory Testing in Large, Prospective, Randomized Clinical TrialsPURPOSE: To critically assess the accuracy and reproducibility of human epidermal growth factor receptor type 2 (HER-2) testing in outside/local community-based hospitals versus two centralized reference laboratories and its effect on selection of women for trastuzumab (Herceptin)-based clinical trials. EXPERIMENTAL DESIGN: Breast cancer specimens from 2,600 women were prospectively evaluated by fluorescence in situ hybridization (FISH) for entry into Breast Cancer International Research Group (BCIRG) clinical trials for HER-2-directed therapies. RESULTS: HER-2 gene amplification by FISH was observed in 657 of the 2,502 (26%) breast cancers successfully analyzed. Among 2,243 breast cancers with central laboratory immunohistochemistry (10H8-IHC) analysis, 504 (22.54%) showed overexpression (2+ or 3+). Outside/local laboratories assessed HER-2 status by immunohistochemistry in 1,536 of these cases and by FISH in 131 cases. Overall, the HER-2 alteration status determined by outside/local immunohistochemistry showed a 79% agreement rate [kappa statistic, 0.56; 95% confidence interval (95% CI), 0.52-0.60], with FISH done by the central laboratories. The agreement rate comparing BCIRG central laboratory 10H8-IHC and outside/local laboratory immunohistochemistry was 77.5% (kappa statistic, 0.51; 95% CI, 0.46-0.55). Finally, HER-2 status, determined by unspecified FISH assay methods at outside/local laboratories, showed a 92% agreement rate (kappa statistic, 0.83; 95% CI, 0.73-0.93), with FISH done at the BCIRG central laboratories. CONCLUSIONS: Compared with the HER-2 status determined at centralized BCIRG reference laboratories, these results indicate superiority of FISH to accurately and reproducibly assess tumors for the HER-2 alteration at outside/local laboratories for entry to clinical trials.
High breast cancer incidence rates among California teachers: results from the California Teachers Study (United States)OBJECTIVE: [corrected] To determine risk factor profiles and cancer incidence rates among participants in the California Teachers Study (CTS), a study designed to document high breast cancer incidence rates of California teachers and to investigate emergent hypotheses in the etiology of breast and other cancers. METHODS: The CTS is a prospective study of 133,479 California female teachers and administrators, established in 1995-1996 with members of the California State Teachers Retirement System completing a detailed mailed questionnaire regarding possible risk factors for breast and other cancers. Cancer outcomes were identified by linkage with the California Cancer Registry. RESULTS: CTS participants have a 51% higher age-standardized invasive breast cancer incidence rate and a 67% higher in-situ breast cancer incidence rate than would be expected based on race-specific statewide rates after three years of follow-up. CTS participants also have substantially elevated rates of endometrial cancer (rate ratio, RR = 1.72), ovarian cancer (RR = 1.28), melanoma (RR = 1.59), non-Hodgkin's lymphoma (RR= 1.53), and leukemia (RR = 1.28), but low rates of invasive cervix cancer (RR = 0.53) and lung cancer (RR = 0.66). CONCLUSIONS: CTS members have high rates of several major cancers, particularly breast cancer, and low rates of lung and cervix cancer. Although late age at first birth can explain a portion of the observed excess risk of breast cancer in this cohort, the unique risk factor profile of CTS members may account for much of their higher risk of breast and selected other cancers. The CTS offers a rich resource for future studies of cancer risk and of women's health, in general.
Human immunodeficiency virus-related lymphoma. Prognostic factors predictive of survivalIn an attempt to determine factors predictive of survival in patients seropositive for human immunodeficiency virus (HIV) with acquired immune deficiency syndrome (AIDS)-related lymphoma, the authors studied 60 such patients, all of whom were treated with curative intent. Eleven patients presented with lymphoma primary to the brain (P-CNS); the remaining 49 had systemic AIDS-related lymphoma. Patients with P-CNS lymphoma had more severe underlying HIV-related disease than did patients with systemic lymphoma as evidenced by a higher incidence of AIDS before the diagnosis of lymphoma (73% versus 37%; P = 0.04), and lower median number of CD-4-positive lymphocytes in peripheral blood at diagnosis of lymphoma (30/dl versus 189/dl; P = 0.005). Median survival of such patients was 2.5 months versus 6.0 months for patients with systemic lymphoma (P = 0.04). Forty patients with systemic AIDS-related lymphoma have died; three factors were strongly associated with shorter survival: (1) Karnofsky performance status (KPS) of less than 70% (multivariate relative survival risk [RSR] = 3.1); (2) history of AIDS before the diagnosis of lymphoma (multivariate RSR = 3.0 for opportunistic infection plus Kaposi's sarcoma); and (3) bone marrow involvement (RSR = 3.1)). All three factors (KPS of less than 70%, prior AIDS diagnosis, and marrow involvement) were associated with early demise attributed to AIDS, whereas death attributed to lymphoma per se was associated with only two factors (KPS of less than 70% and marrow involvement). In the absence of all three risk factors, a "good prognosis" group of 17 patients was defined, with a median survival of 11.3 months; the median survival of the remaining patients ("poor prognosis") was 4.0 months (P = 0.0002). Attainment of complete response to therapy (CR) was strongly related to prolonged survival in the patients in the good prognosis group (17.8 months in patients with CR versus 5.0 months in those with less than CR); however, such meaningful prolongation of survival was not seen in patients with poor prognosis who attained CR (6.3 months versus 3.4 months). The patients with poor prognosis may be unable to tolerate the insult of multiagent chemotherapy, experiencing low CR rates (25%) and death caused by lymphoma and AIDS. However, patients in either prognostic category who attained CR remained at risk for dying of AIDS while the lymphoma was in remission. Thus, it is apparent that meaningful prolongation of survival in the patient with AIDS-related lymphoma will require not only effective antineoplastic intervention, but also control of the underlying HIV infection. In addition, future therapeutic trials should stratify patients based upon the prognostic factors defined here in an attempt to clarify the results obtained.
Lifetime Recreational Exercise Activity and Breast Cancer Risk Among Black Women and White WomenLeslie Bernstein, Alpa V. Patel, Giske Ursin et al.|JNCI Journal of the National Cancer Institute|2005 BACKGROUND: Physical inactivity is a potentially modifiable breast cancer risk factor. Because few data on this relationship exist for black women, we examined the relationship between breast cancer risk and lifetime and time- or age-specific measures of recreational exercise activity among white women and among black women. METHODS: The Women's Contraceptive and Reproductive Experiences Study was a multicenter population-based case-control study of black women and white women aged 35-64 years with newly diagnosed invasive breast cancer. We collected detailed histories of lifetime recreational exercise activity during in-person interviews with 4538 case patients with breast cancer (1605 black and 2933 white) and 4649 control subjects (1646 black and 3033 white). Control subjects were frequency-matched to case patients on age, race, and study site. We examined associations between exercise activity measures (metabolic equivalents of energy expenditure [MET]-hours per week per year) and breast cancer risk overall and among subgroups defined by race, other breast cancer risk factors, and tumor characteristics by use of unconditional logistic regression. All statistical tests were two-sided. RESULTS: Among all women, decreased breast cancer risk was associated with increased levels of lifetime exercise activity (e.g., average MET-hours per week per year, P(trend) = .002). An average annual lifetime exercise activity that was greater than the median level for active control subjects was associated with an approximately 20% lower risk of breast cancer, compared with that for inactivity (for 6.7-15.1 MET-hours/week/year, odds ratio [OR] = 0.82, 95% confidence interval [CI] = 0.71 to 0.93; for > or =15.2 MET-hours/week/year, OR = 0.80, 95% CI = 0.70 to 0.92). The inverse associations did not differ between black and white women (for MET-hours/week/year, P(trend) = .003 and P(trend) = .09, respectively; homogeneity of trends P = .16). No modification of risk was observed by disease stage, estrogen receptor status, or any breast cancer risk factor other than first-degree family history of breast cancer. CONCLUSIONS: This study supports an inverse association between physical activity and breast cancer among black women and among white women.