Abstract P4-13-12: Identifying women at increased risk for breast cancer using the electronic health record in an integrated health system

Women at increased risk for breast cancer (BC) are eligible to take selective estrogen receptor modulators (SERMs) to reduce their risk; Food and Drug Administration (FDA) approval of tamoxifen or raloxifene for BC risk reduction and American Society of Clinical Oncology (ASCO) guidelines for the use of SERMs recommend the two drugs for any woman over the age of 35 years with a 5-year risk of 1.67% or greater, but identifying those women can be both challenging and costly. We used an electronic database (Centricity RIS-IC) from the Geisinger Health System (GHS) Department of Radiology with 77,000 women ages 35–90 years to calculate 5-year and lifetime risks of developing invasive BC using National Cancer Institute's (NCI) Breast Cancer Risk Assessment Macro (BrCa RAM). BrCa RAM calculates risk based on patient age, number of biopsies, did a biopsy ever display atypical hyperplasia (Yes/No), age at menarche, age at first live birth, number of first degree relatives with breast cancer, and patient race. Demographic information (age, race, sex) was obtained from the electronic health record (EpicCare), pathology information (number of biopsies, atypical hyperplasia) was obtained from the pathology application (CoPath), and personal history (number of first degree relatives with breast cancer) were obtained from RIS. Age at menarche and age at first live birth could not be obtained, but makes a small relative contribution to the risk of BC. Sensitivity analysis explored implications of missing data; imputing ages for age at first live birth and age at menarche showed that the absence of this data did not overestimate the five-year and lifetime risks. There were 5,897 patients with calculated 5-year breast cancer risk 2; mean age was 65.8 years, mean 5-yr risk of BC = 3.05% (max 18.2%). The number of patients by 5-year risk score category were: risk 2–2.5% (n = 1728); 2.5%–3% (n = 3188); 3%+ (n = 981). There were 4,196 patients with a GHS primary care physician (PCP); 5,086 patients had seen any Geisinger physician within the past year; 4,113 women had seen their PCP in the past year. Only 239 patients ever received a prescription for tamoxifen or raloxifene, and some received raloxifene for prevention or treatment of osteoporosis and not for BC risk reduction. Only 40 were currently taking tamoxifen or raloxifene. These data from an integrated health system with an electronic health record validate the under-utilization of SERMs for primary BC risk reduction. Strategies are being designed to increase their use in GHS by using the risk score to identify the population and attempt to intervene using a risk modification clinical program.

Citation Information: Cancer Res 2012;72(24 Suppl):Abstract nr P4-13-12.

NSABP B-30: definitive analysis of quality of life (QOL) and menstrual history (MH) outcomes from a randomized trial evaluating different schedules and combinations of adjuvant therapy containing doxorubicin, docetaxel and cyclophosphamide in women with operable, node-positive breast cancer

Abstract #76

Background: QOL and MH outcomes were integrated into the NSABP B-30 trial as secondary outcomes to the efficacy analyses which are being presented separately. Explicit secondary aims of the NSABP B-30 study were 1) to compare toxicities among the regimens, 2) to compare QOL, and 3) to examine differences in amenorrhea and its relationship to symptoms, QOL, and efficacy. Here we examine the secondary aims of the study as a companion to the efficacy results that are presented separately.
 Materials and Methods: 5351 pts with cT1-3, N0-1, M0 were enrolled from 3/1/99 to 3/31/2004. 2170 were enrolled on the QOL study, and 2449 were enrolled on the MH study and were randomized to one of three treatment groups: Group 1 [doxorubicin (A) 60 mg/m2 and C 600 mg/m2 q 3 weeks (wks) x 4 followed by docetaxel (T) 100 mg/m2 q 3 wks x 4; Group 2 [A 50 mg/m2 and T 75 mg/m2 q 3 wks x 4]; Group 3 [A 50 mg/m2 T 75 mg/m2 and cyclophosphamide (C) 500 mg/m2 q 3 wks x 4]. All patients with ER-positive tumors received hormonal therapy after completing chemotherapy. Preliminary results from Group 1 have been reported previously (Swain, et al. Breast Cancer Res Treat, 2008).
 Results: The protocol specifies that 800 deaths are required for the definitive analysis of treatment, QOL, and MH outcomes, which are expected to occur by fall 2008. For this final report, results from a comparison of the three arms will be analyzed and presented.

Citation Information: Cancer Res 2009;69(2 Suppl):Abstract nr 76.

Follow-up of the breast cancer prevention trial and the future of breast cancer prevention efforts

Women who are at increased risk for developing breast cancer can be identified using quantitative risk assessment models that provide valid estimates of risk. The Breast Cancer Prevention Trial (BCPT, P-1) demonstrated that tamoxifen can reduce the incidence of both invasive and noninvasive breast cancer as well as of bone fractures in women at increased risk. These benefits accrue at the expense of increased risk of endometrial cancer, thromboses, cataracts, and possibly diminished quality of life in postmenopausal women. All premenopausal women with a 5-year risk of developing invasive breast cancer greater than 1.67% derive net benefit from using tamoxifen to reduce the risk. Subset analyses of older postmenopausal women taking raloxifene for the treatment of osteoporosis indicate reduction of breast cancer incidence by more than 70%. These findings led the National Surgical Adjuvant Breast and Bowel Project (NSABP) to design and launch the STAR trial (P-2, the Study of Tamoxifen and Raloxifene). Eligible women are at least 35 years of age and postmenopausal, and they must have either lobular carcinoma in situ (LCIS) or a 5-year risk of invasive breast cancer of at least 1.67% as determined by the Gail model [M. H. Gail et al., J. Natl. Cancer Inst. (Bethesda), 81: 1879-1886, 1989]. Subjects are randomly assigned to receive either tamoxifen 20 mg or raloxifene 60 mg daily in a double-blind, double-dummy design. The trial is designed to recruit a total of 22,000 postmenopausal women and is powered to demonstrate superior efficacy of either agent or their equivalence in reducing the incidence of primary breast cancer. Additional end points will include the incidence of cardiovascular events and bone fractures. Thromboembolic events and endometrial cancer are the predicted toxicities. Ancillary studies of cognitive function will also be performed. Raloxifene should not be used for the reduction of breast cancer risk outside the context of the STAR trial.

Reducing the risk of breast cancer with tamoxifen in women at increased risk

Validated quantitative models are available that permit the accurate estimation of a woman's risk of developing invasive breast cancer during a specified period of time. Data from the National Surgical Adjuvant Breast and Bowel Project Breast Cancer Prevention Trial indicate that tamoxifen can reduce the risk of developing breast cancer by at least 49% in women who are at increased risk. All premenopausal women whose 5-year risk of developing breast cancer is 1.67% or greater derive a net benefit from taking tamoxifen for risk reduction. Women who have either lobular carcinoma-in-situ or atypical ductal or lobular hyperplasia derive an even greater net benefit. Women who carry mutations in either the BRCA1 or BRCA2 gene will also experience reduced incidence of breast cancer with tamoxifen. Although postmenopausal women derive a net benefit from tamoxifen through the reduction of both breast cancer and bone fracture event rates, the risks of both invasive endometrial cancer and thromboembolic events must be balanced in older women. Physicians should identify appropriate candidates with whom to discuss the possible benefits of tamoxifen for reducing the risk of breast cancer.

Results and implications of the Royal Marsden and other tamoxifen chemoprevention trials: an alternative view

At the time of the release of the findings of the Breast Cancer Prevention Trial (BCPT), early interim results from two smaller European studies were also released. These smaller studies included one from the Royal Marsden (RM) Hospital in London, England, and another from the Italian National Cancer Institute. Since then, there has been much discussion about the relevance of the interim findings from the European studies and the likely reason for the failure of these studies to find a treatment effect. In some instances, the discussion has been incomplete or inconsistent with the observations from the trial. This has caused some confusion regarding the likely differences among the three studies of breast cancer prevention with tamoxifen. Recently, investigators from the RM study have published their interpretation of the reasons for the negative findings from the European studies. The discussions of the RM investigators are reviewed and used as a basis to illustrate some misconceptions regarding key differences in trial design and implementation among the BCPT and the European trials. The investigator discussions are also used to illustrate the significance of performing an appropriate benefit/risk assessment to identify women who would likely have a net beneficial effect when using tamoxifen to reduce the risk of breast cancer occurrence. Differences in terms of the characteristics of the study populations resulting in inadequate statistical power is the most likely reason for the failure to detect treatment differences in the European trials. Possible confounding due to the use of hormone replacement therapy is another reason that must be considered. Also, benefit/risk analysis indicates that tamoxifen has substantial public health potential as an approach to reduce breast cancer incidence and the physical and mental morbidity associated with this disease. The drug cannot be used indiscriminately due to the potential side effects, but benefit/risk assessment methodology can be used to identify substantial numbers of women in whom treatment would provide a net beneficial effect.

Breast cancer prevention: a review of current evidence

The National Cancer Institute has created a breast cancer risk assessment tool that quickly estimates a woman's individualized absolute risk of developing breast cancer. Understanding the magnitude of risk is important because recent data show that breast cancer incidence may be reduced. All women may improve their overall health and thus perhaps minimize breast cancer risk by maintaining a healthy weight, avoiding cigarettes, limiting alcohol consumption, getting regular exercise, and avoiding non-diagnostic ionizing radiation. Nevertheless, no lifestyle modifications have yet been proven to prevent or definitively lower the risk of breast cancer. In addition, women whose personal breast cancer risk is high may consider reducing risk by pharmacologic or surgical means. In such women, a five-year course of tamoxifen reduced the risk of invasive breast cancer by 49%; women with lobular carcinoma in situ or atypical hyperplasia experienced even greater risk reductions. Because of the potential for vascular and endometrial side effects, women who are candidates for a preventive course of tamoxifen must be counseled regarding its relative risks and benefits. Prophylactic mastectomy offers at least a 90% reduction in the risk of breast cancer, but the physical and psychological changes involved in such a procedure make it a difficult choice for many women. Breast cancer risk assessment and appropriate counseling are becoming standard components of breast cancer screening and overall health maintenance.

American Society of Clinical Oncology 1998 update of recommended breast cancer surveillance guidelines

OBJECTIVE

To determine an effective, evidence-based, postoperative surveillance strategy for the detection and treatment of recurrent breast cancer. Tests are recommended only if they have an impact on the outcomes specified by American Society of Clinical Oncology (ASCO) for clinical practice guidelines.

POTENTIAL INTERVENTION

All tests described in the literature for postoperative monitoring were considered. In addition, the data were critically evaluated to determine the optimal frequency of monitoring.

OUTCOME

Outcomes of interest include overall and disease-free survival, quality of life, toxicity reduction, and secondarily cost-effectiveness.

EVIDENCE

A search was performed to determine all relevant articles published over the past 20 years on the efficacy of surveillance testing for breast cancer recurrence. These publications comprised both retrospective and prospective studies.

VALUES

Levels of evidence and guideline grades were rated by a standard process. More weight was given to studies that tested a hypothesis directly relating testing to one of the primary outcomes in a randomized design.

BENEFITS, HARMS, AND COSTS

The possible consequences of false-positive and -negative tests were considered in evaluating a preference for one of two tests providing similar information. Cost alone was not a determining factor.

RECOMMENDATIONS

The attached guidelines and text summarize the updated recommendations of the ASCO breast cancer expert panel. Data are sufficient to recommend monthly breast self-examination, annual mammography of the preserved and contralateral breast, and a careful history and physical examination every 3 to 6 months for 3 years, then every 6 to 12 months for 2 years, then annually. Data are not sufficient to recommend routine bone scans, chest radiographs, hematologic blood counts, tumor markers (carcinoembryonic antigen, cancer antigen [CA] 15-5, and CA 27.29), liver ultrasonograms, or computed tomography scans.

VALIDATION

The recommendations of the breast cancer expert panel were evaluated and supported by the ASCO Health Services Research Committee reviewers and the ASCO Board of Directors.

The effect of physician recommendation on enrollment in the Breast Cancer Chemoprevention Trial

BACKGROUND

The purpose of this study was to evaluate the effect of physician recommendation on whether to enroll in a randomized controlled chemoprevention trial for breast cancer.

METHODS

We surveyed 360 women who were at increased risk for breast cancer regarding social and behavioral factors that could influence their decision to enroll or not to enroll in the Breast Cancer Prevention Trial (BCPT). Respondents completed a questionnaire following attendance at an informational session about the trial. The analysis was restricted to 175 women who discussed the possibility of their participation in the trial with their primary care physician (PCP) and who reported what their physician advised them to do regarding participation.

RESULTS

Logistic regression modeling showed that among women who discussed the trial with their physician, physician recommendation was the most important factor that influenced the respondent's decision to enroll in the BCPT. Women who reported that their physician advised them to enroll in the trial were 13 times more likely to participate than were women who reported that their physicians advised them not to participate.

CONCLUSIONS

The results of our study show that PCPs play an important role in influencing preventive health behavior, specifically, regarding enrollment in a randomized breast cancer chemoprevention trial. Efforts to increase recruitment to a trial should include enlisting the support of PCPs.

Validation of a model predicting enrollment status in a chemoprevention trial for breast cancer

We evaluated the performance of a regression model in predicting enrollment status in a chemoprevention trial for breast cancer using a population independent of that from which the model was derived. In years 1 and 2 of recruitment, questionnaires were completed by eligible participants following attendance at informational meetings about the Breast Cancer Prevention Trial. The variables in the original model, based on women recruited in year 1, included not being able to take estrogen replacement therapy (ERT), concern about the side effects of tamoxifen, the possibility of getting a placebo, the out-of-pocket expenses associated with the trial, and disagreement with the statement "significant others would be reassured if the respondent was taking tamoxifen." These variables were used to predict enrollment status of women newly recruited to the trial in year 2. Among the 89 women in the study population who responded to the questionnaire, 66% did not enroll in the trial. By applying the original logistic regression model, enrollment status in the trial was correctly predicted for 72% of year 2 questionnaire respondents. Age and risk scores, as binary variables, were used in a derived logistic model to determine whether they provided additional predictive information on enrollment status. The resulting four-factor model, which predicted nonenrollment, included: age of > or = 50 years, not being able to take ERT, expressed concern that significant others would not be reassured if the respondent was taking tamoxifen, and concern about out-of-pocket expenses associated with the trial. This model correctly classified 76% of the respondents. The logistic regression models performed reasonably well in predicting enrollment status. Not being able to take ERT remained the strongest factor predicting nonenrollment. More research is needed to evaluate factors that motivate persons to seek participation in primary chemoprevention trials in culturally diverse populations.

Breast cancer screening

Radiographic imaging of the breast began in the early years of the twentieth century. Continuous advances in film quality, energy sources, targets, grids, and filters have all contributed to superior image resolution. Federal quality standards now regulate screening mammography, and mass screening for breast cancer has become widely accepted in the United States. Wider application of screening has resulted in a dramatic apparent increase in incidence rates of breast cancer; a large proportion of this increase is in ductal carcinoma in situ. During the past 30 years, nine prospective, randomized trials to evaluate the ability of screening mammography to reduce mortality from breast cancer have been completed. These trials show a 30% reduction in mortality for women ages 50-69 years, but the benefit to women aged 40-49 years remains uncertain. This uncertainty is largely attributable to the lack of properly designed and conducted studies to evaluate screening efficacy in younger women. Although there is no biological reason to predict poor screening performance in the younger age groups, the sensitivity of screening mammography is lower in younger women. Additional data suggest that screening intervals longer than 12 months are ineffective in women younger than 50 years. With shorter screening intervals, the cost associated with screening mammography is comparable to other life-saving measures widely applied in the population. New breast imaging techniques hold promise for superior image quality, but they remain investigational as tools for mass screening. Until primary prevention of breast cancer is a reality, mass screening remains available to reduce mortality from breast cancer.

Ethical Issues of Chemoprevention Clinical Trials

BACKGROUND: Chemoprevention of malignancy is a new concept in clinical medicine, and little is written about the ethics of identifying and enrolling eligible subjects in chemoprevention clinical trials. METHODS: The authors identify the ethical issues raised in the conduct of clinical chemoprevention trials and review the ethical considerations that should guide clinical researchers in the design and conduct of this new type of clinical trial. RESULTS: The ethics of chemoprevention clinical trials are complicated because (1) chemoprevention lies at the intersection of disease management and health promotion, (2) there are conflicting interests competing in these trials, and (3) multiple values play a role in determining the nature and magnitude of the risks and benefits of chemoprevention of cancer. Ethical questions related to these trials concern the enrollment of healthy individuals rather than cancer patients, confidentiality in recruitment, the enrollment of "high-risk" subjects, randomization, informed consent, trial monitoring, and competing outcomes and toxicities. CONCLUSIONS: These issues will be resolved with the accumulating clinical experience and ethical deliberations that accompany ongoing clinical chemoprevention research studies.

Breast cancer prevention strategies

The ultimate goal of breast cancer prevention strategies is to reduce the incidence of this disease in populations. Greater understanding of recently identified associations of lactation, alcohol, exercise, and diet with breast cancer is necessary to bring these to bear favorably on the behavior of populations. As a hormonally related process, breast cancer incidence is associated with two major physiologic mechanisms: (1) extent of lobular maturation, which is profoundly influenced by the occurrence of a full-term pregnancy, and (2) hormonal exposure of the breast epithelium, which is influenced by a spectrum of lifestyle factors. Manipulation of these processes by technologically simple and practical means is a major goal of research. Modulation of preclinical growth of breast cancers by chemopreventive means poses significant challenges, due to the absence of target-organ specificity and frequent toxicity. With the emergence of well-supported models of breast cancer development, behavioral and social strategies are likely to be key to achieving the ultimate goal.

Assessing women's potential risk of developing breast cancer

Available data show that women tend to overestimate their risk of developing breast cancer. Available models allow for the rapid identification of women who are at increased risk for breast cancer, along with a quantitative estimate of their probability of developing breast cancer over a period of years or by a certain age. Important risk factors include age; family history of breast cancer in first-degree (mother, sister, or daughter) or second-degree (aunt or grandmother) relatives; history of biopsy for benign breast disease, with or without atypical hyperplasia; nulliparity or first live birth after age 30; and menarche before age 12. Risk should be quantified routinely when women seek advice about breast cancer risk-management strategies. Counseling, with appropriate referrals when required, should always accompany specific recommendations for managing risk. Additional predictive models are needed for nonwhite women and for women not being screened regularly with mammography.

Economic savings and costs of periodic mammographic screening in the workplace

This article discusses the costs and benefits of mammographic screening in the workplace. The cost of mammography itself and of diagnostic work-up are two of the largest costs involved. Therefore, the most efficient approach to providing mammography depends on the number of employees receiving mammography; and the diagnostic accuracy of mammography and underlying incidence of breast cancer in the screened population strongly influence the number of suspicious mammograms that are not associated with breast cancer. The health benefit of mammographic screening is due to reduced mortality and morbidity through early detection and more effective treatment, which may also result in economic savings if early-stage cancer is less expensive to treat. However, the total lifetime cost of treating early-stage cancer may be greater than treating late-stage cancer because of improved survival of early-stage patients. Thus, although periodic mammographic screening is not likely to result in overall economic savings, in many populations of working-age women, especially those with identifiable risk factors, screening is cost-effective because the expenditure required to save a year of life through early detection of breast cancer is low compared to other types of health services for which employers commonly pay.

Who uses screening mammography regularly?

We evaluated factors associated with the regular use of screening mammography among women presenting for screening. Six thousand two hundred forty-four women ages 55 and older who participated in the 1991-1992 Texas Breast Screening Project were classified as regular or irregular users of mammography according to self-reported mammographic history since 1986. Logistic regression was applied to determine odds ratios of specified factors. Fourteen % were regular users of mammographic screening. Being older, black or Hispanic, receiving regular care from a family doctor, believing in a lower prospect of cure of breast cancer, and lacking health insurance coverage were associated with less regular use of screening mammography. Higher educational level, family history of breast cancer, prior breast biopsy, annual income > or = +35,000, receiving regular care from a gynecologist, believing that life would be difficult with breast cancer, and believing in a greater personal risk for breast cancer were associated with a greater likelihood of regular use (P < 0.01). Among multiple factors associated with regular use of screening mammography, sociodemographic variables associated with regular mammography use are similar to those influencing initial use of screening mammography. Women who are difficult to persuade to obtain mammographic screening may be equally difficult to persuade to adhere to regular use.

Factors related to enrollment in the breast cancer prevention trial at a comprehensive cancer center during the first year of recruitment

BACKGROUND

Using an a priori theoretic model of behavior change, factors predicting enrollment in a randomized chemoprevention trial during the first year of recruitment were assessed prospectively.

METHODS

Eligible participants were asked to complete a 90-item semistructured questionnaire after attendance at an informational meeting. Components of the Health Belief Model (including perceived susceptibility, perceived severity, perceived benefits and barriers, cues to action, and health motivation), health status, preventive health behaviors, and social influence were assessed in relation to enrollment.

RESULTS

Overall, 331 women attended one of the meetings, and 73% completed a questionnaire; 45% enrolled on the trial and 55% did not. In bivariate analyses, all but one of the perceived barriers were associated negatively with enrollment; however, items assessing perceived susceptibility, perceived severity, and perceived benefits were not. Nonparticipants also were more likely to be over 49 years of age, to be currently or to have been on estrogen replacement therapy, and to have had hot flashes. In logistic regression analysis, not being able to take estrogen replacement therapy was the strongest predictor of nonparticipation (odds ratio [OR], 12.13, 95% confidence interval [CI], 3.63, 40.60). Other factors associated with nonparticipation were concern about side effects of tamoxifen (OR, 5.06; CI, 2.37, 10.80); the possibility of getting a placebo (OR, 7.75; CI, 1.51, 39.67); the costs associated with the trial (OR, 3.21; CI, 1.12, 9.24); and absence of concern that significant others would be reassured if the respondent was taking tamoxifen (OR, 2.58; CI, 1.04, 6.41).

CONCLUSIONS

These findings support the view that recruitment efforts for chemoprevention trials should address barriers specific to their circumstances. In addition, increasing the support available from personal social networks may enhance recruitment to chemoprevention trials for breast cancer.

Validation of a breast cancer risk assessment model in women with a positive family history

BACKGROUND

Gail et al. developed a statistical model for estimating the risk of developing breast cancer in white women screened annually with mammography. This model is used for counseling and for admission to clinical trials.

PURPOSE

We evaluated the model prospectively in a cohort of women with a family history of breast cancer.

METHODS

We followed women who participated in the American Cancer Society 1987 Texas Breast Screening Project. The model was evaluated by comparing the observed (O) and expected (E) numbers of breast cancers using composite background rates from both the Breast Cancer Detection and Demonstration Project and the Surveillance, Epidemiology, and End Results program of the National Cancer Institute. Data were partitioned by adherence to American Cancer Society screening guidelines.

RESULTS

The Gail et al. model predicted the risk well among women who adhered to the American Cancer Society guidelines (O/E = 1.12; 95% confidence interval = 0.75-1.61) but overpredicted risk for women who did not adhere to the guidelines. There was an indication that the model overpredicted risk for women younger than 60 years old and underpredicted risk in women aged 60 years and older.

CONCLUSIONS

Overall, the Gail et al. model accurately predicts risk in women with a family history of breast cancer and who adhere to American Cancer Society screening guidelines. Thus, the model should be used as it was intended, for women who receive annual mammograms.

Factors associated with perceived risk of breast cancer among women attending a screening program

A person's perception of the risk of, or susceptibility to, developing a disease is believed to be an important determinant of health-related behavior, yet little is known about the determinants of perceived risk. Knowledge of these correlates may be useful in identifying and addressing barriers to performance of health behaviors such as mammography screening. Data collected from over 36,000 women participating in a breast cancer screening program in Texas were used to examine the associations between perceived risk of ever getting breast cancer and a number of demographic factors, health-related behaviors, and risk factors for breast cancer. There was a strong positive association between family history of breast cancer and risk perception (OR = 11.3, CI = 10.34-12.35). Women who reported other risk factors for breast cancer also reported higher perceived risk, but those associations were of lesser magnitude. Age was inversely associated with perceived risk, and black, but not Hispanic, women were more likely to perceive their risk as high compared with white women. Of the health-related behaviors for the early detection of breast cancer, only having had a prior mammogram was associated with perceived risk. Educational interventions to heighten women's awareness of breast cancer risk factors may increase perceived risk in high risk women and influence their decision to undergo screening mammography.

Clinical management of women at increased risk for breast cancer

A large number of women in the population are at risk for the development of breast cancer. Methods now exist to accurately assess risk and to provide quantitative estimates of the chance of a woman developing breast cancer in her lifetime. Histologic assessment of premalignant breast pathology aids in the evaluation of risk. The availability of primary chemoprevention clinical trials reduces the number of indications for prophylactic mastectomy. Women at risk for breast cancer and women who have had a malignant lesion at another anatomic site have an increased risk for new cancers at multiple sites. We propose screening strategies based on epidemiologic information about the risks of these diseases and on the predictive value of the available screening tests. The merits and inadequacies of specific management strategies are considered. We review the risks and benefits of estrogen replacement therapy for women at increased risk for breast cancer and consider the ethical implications of both risk assessment and the various interventions.

The Texas Breast Screening Project: Part II. Demographics, risk profiles, and health practices of participants

More than 36,000 of the 64,459 women who had $50 mammograms after a media campaign in 1987 completed a demographic and risk factor questionnaire. The screened women were young and well educated with high annual incomes. Only 32% had had mammograms before 1987. Most women reported that high cost and lack of referral for mammography by their physicians were their reasons for not being screened previously. Publicity promoting the project and the lower cost for mammography were the features of the project that attracted participants. Population-based telephone surveys before and after the project showed a change in attitudes about breast cancer screening. The model used for recruitment in this project can improve compliance with recommendations for regular mammographic screening if charges for screening are reduced. Additional efforts are needed to attract minorities and poor or elderly women to regular breast screening.

The Texas Breast Screening Project: Part I. Mammographic and clinical results

The 1987 Texas Breast Screening Project was designed to educate women about the benefits and safety of mammographic screening. During the 2-week promotion, 109,339 women called toll-free telephone numbers to inquire about the program, and 64,459 (65%) of 99,650 eligible callers had $50 mammograms at 306 participating community radiology centers. Biopsies were obtained for 1,122 women (1.7% of those screened), and the ratio of benign to malignant biopsy results was 4.2:1. Among the women having biopsies, 214 cancers were found (3.3 cancers per 1,000 women screened). Forty-seven percent of the tumors were not palpable, 80% were smaller than 2 cm, and 72% were clinicopathologic stage 0 or I. These results show that women will respond to an invitation to attend mammographic screening, and that community radiology centers can detect large numbers of early, curable breast cancers.

Epidemiology and etiology of leukemia

New clinical and epidemiologic studies provide information about the possible causes of human leukemia. Evidence for a viral etiology continues to appear, and the relationship between myelodysplastic syndrome and the leukemias is now linked through molecular genetic studies. Molecular mechanisms of leukemogenesis are being understood through evaluation of preleukemic conditions and predisposing medical illnesses. Epipodophyllotoxins and, to a lesser extent, cisplatin are being linked causally to secondary leukemia. Potential environmental causes of leukemia are being intensively investigated with both positive and negative results. The literature on the epidemiology of leukemia is growing rapidly, and important leads toward a more complete understanding of its etiology are emerging.

Early detection, epidemiology, and prevention of breast cancer

Control of breast cancer will ultimately be achieved through a better understanding of the epidemiology of the disease and application of primary prevention. Until then, use of screening mammography offers the promise of a 30% reduction in breast cancer mortality, which continues to be shown by screening studies with prolonged follow-up. Biologic markers of cancer risk, including nipple aspirates and cyst fluid, suggest that a complete risk profile can be developed using fluid and tissue obtained from the normal breast. Epidemiologic studies of dietary factors and geographic differences in breast cancer risk continue to provide promising leads relating to the etiology of the disease. Increasing evidence suggests that circulating androgens and estrogens affect breast cancer risk, whereas exogenous estrogen therapy does not increase risk except for small subgroups of women at risk. Increasing understanding of the genetics of breast cancer will have an impact on the disease in the near future. The greatest impact in the short term will come from the use of tamoxifen for primary prevention of breast cancer. The retinoids, particularly N-(4-hydroxyphenyl)retinamide, hold great promise as agents for primary prevention.

Low incidence of familial breast cancer among Hispanic women

There is a paucity of data on familial patterns of breast cancer among minority populations. This study compared the frequency of cancer in 1,095 first-degree relatives of 50 White, 46 Black, and 49 Hispanic breast-cancer patients referred to The University of Texas M.D. Anderson Cancer Center (United States). Family histories of cancer were derived from a self-administered questionnaire on risk factors. Expected numbers of cancers were calculated from the Connecticut Tumor Registry for White and Black relatives and from the New Mexico Tumor Registry for Hispanic relatives. Family history of a first-degree relative with breast cancer was the most important risk factor for both Black and White patients. Significantly elevated standardized incidence ratios (SIR) for breast cancer were noted among White (SIR = 4.5, 95 percent confidence interval [CI] = 1.2-11.4) and Black (SIR = 4.1, CI = 1.1-10.4) relatives younger than age 45. Despite the small number of Black patients, the combined effect of family history of breast cancer and the relative's age at diagnosis (under 45 years) was associated with an SIR of 7.1 (CI = 1.9-18.1). A deficit of cancer was noted in Hispanic women; only one patient reported having a first-degree relative with breast cancer. These findings, although based on small numbers, suggest that Hispanics have a lower rate of familial breast cancer than Whites and Blacks, and that they may possess protective factors that reduce their risk for breast cancer.

Design and conduct of a low-cost mammography screening project: experience of the American Cancer Society, Texas Division

To improve compliance with recommendations for screening mammography, the American Cancer Society (ACS) Texas Division designed and conducted a media-promoted screening project in 1987. The project was planned during a 2-year period by a task force made up of physicians and lay members of ACS division committees. Radiology centers desiring to participate in the project were asked to submit information about the number of patients they could screen and their equipment, along with physics data, to a review committee. Of 306 facilities that responded, 266 (87%) passed the initial review. Thirteen facilities (4%) submitted images from two examinations using a dedicated mammography phantom, and 27 sites (9%) entered the project by agreeing to adhere to the project standards and guidelines without undergoing formal review. All facilities agreed to provide mammograms for $50 to women scheduling appointments during a 2-week media campaign in February 1987. The project generated 64,459 mammographic screening examinations. Our experience indicates that a media campaign can encourage women to have screening mammograms and that screening facilities will agree to screen a large number of women at reduced cost. This strategy, if widely applied, can improve compliance with mammographic screening recommendations and reduce breast cancer mortality.

Identification of women at increased risk for breast cancer in a population-based screening program

A multivariate model to assess breast cancer risk was developed by Gail et al. (M. H. Gail, L. A. Brinton, D. B. Byar, D. K. Corle, S. B. Green, C. Schairer, and J. J. Mulvihill, J. Natl. Cancer Inst., 81: 1879-1886, 1989) based on data analysis of the Breast Cancer Detection and Demonstration Project. We evaluated the model's usefulness for assigning women to risk groups for counseling and follow-up by applying it to the 1987 Texas Breast Screening Project data. We identified 3165 women with one or more first-degree relatives affected with breast cancer. The mean risk score for the group was 3.3 (range, 2.7-11.8), indicating a greater than 3-fold elevated risk. The mean risk score for the remaining 27,439 women without affected first-degree relatives was 1.5 (range, 1.24-3.2). Risk perception was found to be a motivator for participation. Women with a risk score greater than 5 perceived themselves to be at high risk for breast cancer. The perception of risk was related to the type of affected first-degree relatives: 80.0% of the women with three affected first-degree relatives and 71.5% of women whose mother and sister were both affected with breast cancer perceived themselves to be at high risk. The Gail model is potentially useful in the clinical setting because women at high risk for breast cancer can be entered into etiological studies, enrolled in primary prevention trials, or referred to programs seeking to improve compliance with screening mammography. The Gail model needs validation, but it is useful for estimating the risk of breast cancer in large populations.

Breast cancer screening behaviors and attitudes in three racial/ethnic groups

Data from a multiethnic sample of women participating in the American Cancer Society 1987 Texas Breast Screening Project was used to compare attitudes and behaviors related to breast cancer screening for whites, blacks, and Hispanics. In general, similar patterns of association were observed across racial/ethnic groups between a number of demographic and risk factors and prior mammography and recent clinical breast examination (CBE), although the magnitude of the associations varied somewhat across groups. Reasons for not having had prior mammography also were similar across groups, with lack of physician referral and cost cited as the two most important reasons. However, Hispanics were less likely than blacks or whites to report prior breast cancer screening, including mammography, CBE, and breast self-examination (BSE). This study demonstrated that women of different racial/ethnic backgrounds can be successfully recruited to participate in a patient-initiated, community-based program. However, this programmatic approach requires augmentation with other intervention strategies designed to reach low-income women because women with more years of education and higher family income were overrepresented in all three groups.

High-risk populations as targets for breast cancer prevention trials

Breast cancer risk factors include age; a family history of the disease in first-degree relatives (particularly if premenopausal with bilateral disease); proliferative benign breast disease with or without atypia; mammographic parenchymal pattern showing glandular, dense, dysplastic, or Wolfe P2 changes; and obesity. Women in these risk groups have annual breast cancer incidence rates 2 to 10 times higher than baseline. Using data from the National Cancer Institute SEER Program, the U.S. 1987 census estimates, and published prevalence and incidence estimates for breast cancer risk factors, estimates were made for the number of women in the white female population who are at increased risk for breast cancer and who might serve as suitable subjects for an antiestrogen chemoprevention intervention trial. More than 30 million white women are older than 50 years. Two million women older than 50 years have at least one first-degree relative with breast cancer. Six million women over age 50 have undergone breast biopsy for benign disease; one-fourth of these women have proliferative changes, and 11% also have a family history of breast cancer. More than 8 million women older than 50 years are obese, and at least a million older women have high-risk mammographic parenchymal patterns. Thus, there are at least 12 million women at increased risk for breast cancer in the United States, and each year 200,000 additional women enter the high-risk pool. These data indicate that sufficient numbers of women at increased risk for breast cancer are present in the population to justify a chemoprevention trial. The optimal recruitment strategy is yet to be identified.

Mammographic screening of women with increased risk of breast cancer

Five hundred one women from Dallas County, Texas who participated in the American Cancer Society 1987 Texas Breast Screening Project were selected because of a self-reported family history of breast cancer (cases). They were matched with 501 randomly selected women from the same county with no family history (controls). Although there was a statistically significant trend with age for an increasing proportion of women to report having undergone mammography, there was no significant difference when comparing mammographic histories of cases with controls after controlling for age (31.5% versus 35.1%, P = 0.33). Significantly more cases (79%) perceived their risk for breast cancer to be moderate or greater compared with controls (54%, P less than 0.0001), but mammographic histories were not different when controlling for perceived risk. Both cases and controls cited lack of physician referral and cost as their reasons for not having undergone mammography. Women at increased risk for breast cancer (because of their family history) are not undergoing regular mammographic screening despite their self-awareness of the increase in their risk.

Inhibition of protein kinase C by the 12-O-tetradecanoylphorbol-13-acetate antagonist glycyrrhetic acid

Glycyrrhetic acid is an anti-inflammatory agent isolated from licorice root that inhibits 12-O-tetradecanoylphorbol-13-acetate (TPA)-mediated tumor promotion in mouse skin. Although it has been established that glycyrrhetic acid inhibits a number of events induced by the phorbol ester tumor promoter TPA in cultured cells, its mechanisms of action has remained obscure. In this report, we demonstrate that glycyrrhetic acid inhibits the Ca2+-and phospholipid-dependent phosphotransferase activity of protein kinase C (PKC), the phorbol ester tumor promoter receptor. Therefore, inhibition of PKC may play a role in the anti-promoting activity of glycyrrhetic acid.

Elevated protein kinase C expression in human breast tumor biopsies relative to normal breast tissue

The Ca2+- and phospholipid-dependent protein kinase, protein kinase C (PKC), is a critical enzyme in the regulation of cell growth. In this report, we demonstrate elevated expression of PKC activity in surgical specimens of eight of nine spontaneous human breast tumors, as compared with the expression of PKC activity in normal breast tissue obtained from the same patients. The mean PKC specific activity in histologically normal breast tissue was 166 +/- 63 pmol 32P/min/mg, whereas the mean PKC specific activity in the breast tumors was 460 +/- 182 pmol 32P/min/mg (P = 0.0003; Student's t test). The low interpatient variability among the PKC levels observed in the histologically normal breast tissue specimens and the significant elevation of PKC levels observed in the tumors indicate that elevated expression of PKC activity in breast tissue is a potential marker for malignant disease in the breast.

Dietary epidemiology of colon cancer

Epidemiologic studies of the relationship of diet to cancer etiology are hampered by methodologic difficulties which can be overcome by careful trial design. The use of appropriate dietary assessment instruments is necessary to minimize bias and improve accuracy of diet assessment. Population studies implicate dietary fat intake in the etiology of colorectal carcinogenesis, and the incidence of colorectal malignancies around the world is positively correlated with meat and fat consumption and total calorie intake. Retrospective studies of fat intake yield equivocal results, whereas prospective studies have failed to show a relationship between fat intake and colon cancer risk. An inverse relationship exists between fiber consumption and colorectal cancer incidence and mortality rates. The positive observational studies are supported by laboratory studies of experimental carcinogenesis which show a greater number of tumors in animals fed high-fat or high-calorie diets. Increased fiber intake appears to offer some protection against colorectal cancer. Plausible mechanisms have been proposed in animals for the role of fat and fiber in colorectal carcinogenesis; the mechanisms in human populations await further description. The interrelationships between fat consumption and consumption of dietary fiber and micronutrients have made it difficult to assess the roles of these substances in the etiology of colorectal cancer. Calcium offers protection in animal systems, and the data in humans are suggestive but not yet conclusive. Data on the role of alcohol in colorectal carcinogenesis remain inconclusive. Little evidence exists for a protective effect of retinoids and carotenoids; the evidence for selenium and vitamin C is limited and evolving.

Personal risk factors. What do they mean?

Epidemiologic studies have identified myriad factors related to cancer risk. Risk can be quantified on the basis of demographic factors, genetics, occupation, medical conditions, and lifestyle. Existing evidence suggests that: (1) individuals at risk often are unaware of their risk; (2) physicians may not know well those factors associated with the highest cancer risk; and (3) methods to reduce risk have been under-applied because of lack of knowledge, lack of funds, or lack of motivation among both patients and physicians. Methods to reduce risk do not follow the usual medical model in that those groups requiring risk-modification intervention usually are symptom free. Evidence indicates that elimination of tobacco use would reduce lung cancer deaths by 83% and substantially reduce the incidence of head and neck malignancies. Broad application of mammographic screening would effect a 30% reduction in breast cancer mortality. Dietary modification could potentially reduce cancer mortality by 30%. An effective program to reduce cancer risk will accomplish the following: (1) develop new and refine existing risk factor measurements to improve identification of individuals at risk; (2) apply risk factor identification and modification more completely to populations known to be at risk; (3) use combinations of risk factors to identify subpopulations at the highest risk; (4) apply existing prevention and screening modalities more broadly and uniformly; (5) identify new screening strategies with improved test performance and cost effectiveness to maximize screening efficiency; and (6) provide accurate and rapid means of risk assessment and quantification using the best available multivariate estimates of risk. An emphasis on education of primary care physicians to practice cancer prevention programs focused on personal risk profiles is reasonable since the populations these physicians serve express risk factors which represent 50% of the attributable risk for cancer in the US. A summary of site-specific risk factors which are amenable to intervention by primary care physicians is provided.

Venoocclusive disease of the liver following bone marrow transplantation

Review of 235 consecutive patients undergoing bone marrow transplantation was performed in order to define the clinical syndrome of venoocclusive disease of the liver (VOD) in these patients. Analysis of all patients with histologically proven VOD revealed a consistent clinical syndrome of liver dysfunction occurring within the first 3 weeks after marrow infusion. This was characterized by hyperbilirubinemia peaking at greater than or equal to 2 mg/dl with at least 2 of 3 other findings: hepatomegaly, ascites, and 5% or greater weight gain. VOD developed in 22% (52 of 235). A persistently elevated aspartate aminotransferase (SGOT) prior to transplant was associated with an increased risk of developing VOD by multivariate analysis (P = 0.0003), and acute leukemia in first remission was associated with a decreased risk (P = 0.02). Neither the preparative regimen (busulfan and cyclophosphamide versus cyclophosphamide and total body irradiation) nor the type of graft (allogeneic versus autologous) influenced the occurrence. Twenty-four of these 52 patients (47%) died with VOD (10% of the entire group). This makes VOD the third leading cause of death in our allogeneic graft recipients, and the second leading cause in our patients receiving autologous transplants. VOD is a common complication of bone marrow transplantation and has a specific clinical presentation, which usually allows diagnosis without the need of liver biopsy.