Acceptance of tamoxifen chemoprevention by physicians and women at risk

Making Informed Choices On Incorporating Chemoprevention into carE (MiCHOICE, SWOG 1904): Design and methods of a cluster randomized controlled trial

INTRODUCTION

Women with atypical hyperplasia (AH) or lobular carcinoma in situ (LCIS) have a significantly increased risk of breast cancer, which can be substantially reduced with antiestrogen therapy for chemoprevention. However, antiestrogen therapy for breast cancer risk reduction remains underutilized. Improving knowledge about breast cancer risk and chemoprevention among high-risk patients and their healthcare providers may enhance informed decision-making about this critical breast cancer risk reduction strategy.

METHODS/DESIGN

We are conducting a cluster randomized controlled trial to evaluate the effectiveness and implementation of patient and provider decision support tools to improve informed choice about chemoprevention among women with AH or LCIS. We have cluster randomized 26 sites across the U.S. through the SWOG Cancer Research Network. A total of 415 patients and 200 healthcare providers are being recruited. They are assigned to standard educational materials alone or combined with the web-based decision support tools. Patient-reported and clinical outcomes are assessed at baseline, after a follow-up visit at 6 months, and yearly for 5 years. The primary outcome is chemoprevention informed choice after the follow-up visit. Secondary endpoints include other patient-reported outcomes, such as chemoprevention knowledge, decision conflict and regret, and self-reported chemoprevention usage. Barriers and facilitators to implementing decision support into clinic workflow are assessed through patient and provider interviews at baseline and mid-implementation.

RESULTS/DISCUSSION

With this hybrid effectiveness/implementation study, we seek to evaluate if a multi-level intervention effectively promotes informed decision-making about chemoprevention and provide valuable insights on how the intervention is implemented in U.S.

CLINICAL SETTINGS

TRIAL REGISTRATION

NCT04496739.

The Gail Model and Its Use in Preventive Screening: A Comparison of the Corbelli Study

Background This study aims to determine the usage of the Gail model in screening for breast cancer during physical examinations of women by sampling primary care physicians in two regions of Texas - Hidalgo County and Johnson County. A Gail score of 1.66% or higher indicates increased breast cancer risk. Three specialties are surveyed: internal medicine (IM), family medicine (FM), and gynecology (GYN). The null hypothesis for this study is that primary care physicians do not use the Gail model in screening for breast cancer during physical examinations of women. Methods A survey was distributed to 100 physicians with specialties in IM, FM, and GYN from May 2022 to July 2022. The survey assessed the physician's frequency of use of the Gail model and chemoprevention. Data were collected by distributing survey questionnaires to physicians in person. Descriptive statistics were used for response distributions. Fisher's exact probability test was used for comparisons across specialties. Results The response rate was 34% (34/100). Thirty-eight percent of the physicians surveyed reported using the Gail model in their practice (IM 46%, FM 23%, and GYN 31%). All 13 of the physicians using the Gail model were open to using chemoprevention. Conclusions Only 38% of the physicians surveyed responded that they use the Gail model in their practice. The study concluded that a minority of primary care physicians used the Gail model to decrease breast cancer risk. Further research would help to define better the Gail model and its use in preventing breast cancer in women. The Gail model appears to be beneficial to breast cancer risk reduction; however, risk reduction medication side effects need to be minimized.

Non-systemic Approaches for Ductal Carcinoma In Situ: Exploring the Potential of Ultra-flexible Combisomes as a Novel Drug Delivery Strategy-a Review

Ductal carcinoma in situ (DCIS) is currently treated through breast-conserving surgery (lumpectomy), radiation therapy, breast-removing surgery (mastectomy), and hormone therapy to prevent further progression into invasive breast cancer and recurrence. Discrepancies concerning the prognosis of DCIS have sparked controversy about adequate treatment. Considering the severe medical and psychological consequences of mastectomy, developing a treatment approach that arrests the progression of DCIS to the invasive stage without affecting the non-cancerous cells is of utmost importance. In the current review, the problems associated with the diagnosis and management of DCIS have been thoroughly discussed. A summary of the route of administration and drug delivery systems to manage DCIS was also provoked. Innovative ultra-flexible combisomes were also proposed for the effective management of DCIS. Prevention is essential in managing the risk of DCIS and reducing the risk of progression to invasive breast cancer. While prevention is vital, it is not always possible to prevent DCIS, and in some cases, treatment may be necessary. Hence, this review recommends that ultra-flexible combisomes administered as a topical gel provide a non-systemic approach for managing DCIS and thus significantly minimize the side effects and costs associated with existing therapies.

Patient and Provider Web-Based Decision Support for Breast Cancer Chemoprevention: A Randomized Controlled Trial

Significant underutilization of breast cancer chemoprevention remains, despite guidelines stating that physicians should recommend chemoprevention with antiestrogen therapy to high-risk women. We randomized women, ages 35 to 75 years, who met high-risk criteria for breast cancer, without a personal history of breast cancer or prior chemoprevention use, to standard educational materials alone or combined with a web-based decision aid. All healthcare providers, including primary care providers and breast specialists, were given access to a web-based decision support tool. The primary endpoint was chemoprevention uptake at 6 months. Secondary outcomes included decision antecedents (perceived breast cancer risk/worry, chemoprevention knowledge, self-efficacy) and decision quality (decision conflict, chemoprevention informed choice) based upon patient surveys administered at baseline, 1 and 6 months after randomization. Among 282 evaluable high-risk women enrolled from November 2016 to March 2020, mean age was 57 years (SD, 9.9) and mean 5-year invasive breast cancer risk was 2.98% (SD, 1.42). There was no significant difference in chemoprevention uptake at 6 months between the intervention and control groups (2.1% vs. 3.5%). Comparing the intervention and control arms at 1 month, there were significant differences among high-risk women in accurate breast cancer risk perceptions (56% vs. 39%, P = 0.017), adequate chemoprevention knowledge (49% vs. 27%, P < 0.001), mean decision conflict (34.0 vs. 47.0, P < 0.001), and informed choice (41% vs. 23%, P = 0.003). These differences were no longer significant at 6 months. Although our decision support tools did not result in a significant increase in chemoprevention uptake, we did observe improvements in decision antecedents and decision quality measures.

PREVENTION RELEVANCE

In this randomized controlled trial of decision support for 300 high-risk women and 50 healthcare providers, we did not observe a significant increase in chemoprevention uptake, which remained low at under 5%. However, these decision support tools may increase knowledge and informed choice about breast cancer chemoprevention.

Breast Cancer Chemoprevention: Use and Views of Australian Women and Their Clinicians

Guidelines endorse the use of chemoprevention for breast cancer risk reduction. This study examined the barriers and facilitators to chemoprevention use for Australian women at increased risk of breast cancer, and their clinicians. Surveys, based on the Theoretical Domains Framework, were mailed to 1,113 women at ≥16% lifetime risk of breast cancer who were enrolled in the Kathleen Cuningham Foundation Consortium for Research into Familial Breast Cancer cohort study (kConFab), and their 524 treating clinicians. Seven hundred twenty-five women (65%) and 221 (42%) clinicians responded. Only 10 (1.4%) kConFab women had ever taken chemoprevention. Three hundred seventy-eight (52%) kConFab women, two (3%) breast surgeons, and 51 (35%) family physicians were not aware of chemoprevention. For women, the strongest barriers to chemoprevention were side effects (31%) and inadequate information (23%), which operate in the Theoretical Domains Framework domains of "beliefs about consequences" and "knowledge," respectively. Strongest facilitators related to tamoxifen's long-term efficacy (35%, "knowledge," "beliefs about consequences," and "goals" domains), staying healthy for family (13%, "social role" and "goals" domains), and abnormal breast biopsy (13%, "environmental context" domain). The strongest barrier for family physicians was insufficient knowledge (45%, "knowledge" domain) and for breast surgeons was medication side effects (40%, "beliefs about consequences" domain). The strongest facilitators for both clinician groups related to clear guidelines, strong family history, and better tools to select patients ("environmental context and resources" domain). Clinician knowledge and resources, and beliefs about the side-effect consequences of chemoprevention, are key domains that could be targeted to potentially enhance uptake. PREVENTION RELEVANCE: Despite its efficacy in reducing breast cancer incidence, chemoprevention is underutilised. This survey study of Australian women and their clinicians used behavioural change theory to identify modifiable barriers to chemoprevention uptake, and to suggest interventions such as policy change, educational resources and public campaigns, that may increase awareness and use.See related Spotlight by Vogel, p. 1.

Disparities in Risk Reduction Therapy Recommendations for Young Women With Lobular Carcinoma In-Situ

BACKGROUND

Endocrine therapy (ET) significantly reduces the risk of breast cancer development in high-risk patients diagnosed with lobular carcinoma in situ (LCIS). However, the variables impacting recommendation and use of ET in young adults (YAs) is not well-studied. We examined the role of provider recommendation and patient acceptance for ET for YAs with LCIS.

MATERIALS AND METHODS

The National Cancer Database was queried for women aged < 40 years with primary LCIS between 2000 and 2012. Socioeconomic, demographic, and treatment variables were examined to determine their impact on ET provider recommendation and initial patient acceptance of risk-reducing therapy.

RESULTS

Among 1650 YA patients with LCIS, only 749 (45.4%) were recommended ET. On multivariable analysis, women > 30 years of age were more likely recommended ET than women < 30 years (odds ratio [OR], 1.64; 95% confidence interval [CI], 1.10-2.47), African Americans more than other ethnicities (OR, 1.48; 95% CI, 1.1-2.0), and YAs treated in New England were more likely than those in the rest of the country (OR, 3.26; 95% CI, 2.0-5.2). Among YA women recommended ET, only 20.2% had a documented refusal. Only geography appeared to independently impact the likelihood of refusal, with YAs in the Southeastern-Central United States being most likely to refuse ET (OR, 5.4; 95% CI, 1.2-24.0).

CONCLUSION

ET is underutilized for risk-reduction in YAs with LCIS. This underuse appears dependent on disparities in provider recommendation practices rather than non-acceptance of therapy. This may reflect regional practice patterns, community standards of care, or provider bias regarding the significance of LCIS as a risk factor for development of invasive cancer.

Study protocol: Randomized controlled trial of web-based decision support tools for high-risk women and healthcare providers to increase breast cancer chemoprevention

BACKGROUND

Chemoprevention using selective estrogen receptor modulators and aromatase inhibitors has been shown to reduce invasive breast cancer incidence in high-risk women. Despite this evidence, few high-risk women who are eligible for chemoprevention utilize it as a risk-reducing strategy. Reasons for low uptake include inadequate knowledge about chemoprevention among patients and healthcare providers, concerns about side effects, time constraints during the clinical encounter, and competing comorbidities.

METHODS/DESIGN

We describe the study design of a randomized controlled trial examining the effect of two web-based decision support tools on chemoprevention decision antecedents and quality, referral for specialized counseling, and chemoprevention uptake among women at an increased risk for breast cancer. The trial is being conducted at a large, urban medical center. A total of 300 patients and 50 healthcare providers will be recruited and randomized to standard educational materials alone or in combination with the decision support tools. Patient reported outcomes will be assessed at baseline, one and six months after randomization, and after their clinic visit with their healthcare provider.

DISCUSSION

We are conducting this trial to provide evidence on how best to support personalized breast cancer risk assessment and informed and shared decision-making for chemoprevention. We propose to integrate the decision support tools into clinical workflow, which can potentially expand quality decision-making and chemoprevention uptake.

TRIAL REGISTRATION

NCT03069742.

Chemoprevention Uptake for Breast Cancer Risk Reduction Varies by Risk Factor

BACKGROUND/OBJECTIVE

The efficacy of chemoprevention for breast cancer risk reduction has been demonstrated in randomized controlled trials; however, use remains low. We sought to determine whether uptake differed by risk factors, and to identify reasons for refusal and termination.

METHODS

Women seen in a high-risk clinic from October 2014 to June 2017 considered eligible for chemoprevention (history of lobular carcinoma in situ, atypia, family history of breast/ovarian cancer, genetic mutation, or history of chest wall radiation) were retrospectively identified. Breast cancer risk factors were compared among those with and without chemoprevention use, and compliance was noted.

RESULTS

Overall, 1506 women were identified, 24% with prior/current chemoprevention use. Women ≥ 50 years of age were more likely to use chemoprevention than women < 50 years of age (28% vs. 11%, p < 0.001). Chemoprevention use by risk factor ranged from 7 to 40%. Having multiple risk factors did not increase use. Significant variation by risk factor was present among women ≥ 50 years of age (p < 0.001), but not among women < 50 years of age (p = 0.1). Among women with a documented discussion regarding chemoprevention (575/1141), fear of adverse effects was the most common refusal reason (57/156; 36%). The majority of women (61%) who initiated chemoprevention completed 5 years.

CONCLUSION

Chemoprevention use among women at increased risk for breast cancer remains low, with more frequent use among women ≥ 50 years of age. These data highlight the need for ongoing educational efforts and counseling, as the majority who begin therapy complete 5 years of use. Given the fear of adverse effects as well as low uptake, particularly among women < 50 years of age, alternative risk-reducing strategies are needed.

Deciding on breast cancer risk reduction: The role of counseling in individual decision-making - A qualitative study

OBJECTIVES

The presentation of risks and benefits in clinical practice is common particularly in situations in which treatment recommendations involve trade-offs. The treatment of breast cancer risk with selective estrogen receptor modulators (SERMs) is such a decision. We investigated the influence of health care provider (HCP) counseling on women's decision-making.

METHODS

Thirty breast cancer risk counseling sessions were recorded from April 2012-August 2013 at a comprehensive cancer center and at a safety-net, community hospital in the US. Participating women and HCPs were interviewed. A cross-case synthesis was used for analysis.

RESULTS

Of 30 participants 21 received a SERM-recommendation, 11 decided to take SERMs. Counseling impacted decision-making, but did not determine it. Three categories emerged: 1.) ability to change the decision anytime, 2.) perceptions on medications, and 3.) proximity of cancer.

CONCLUSION

Decision-making under conditions of a risk diagnosis such as increased breast cancer risk is a continuous process in which risk information is transformed into practical and experiential considerations.

PRACTICE IMPLICATIONS

Individuals' health care decision-making is only marginally dependent on the interactions in the clinic. Accepting patients' experiences and beliefs in their own right and letting them guide the discussion may be important for a satisfying decision-making process.

Motivators and barriers of tamoxifen use as risk-reducing medication amongst women at increased breast cancer risk: a systematic literature review

Background

Selective estrogen receptor modulators, such as tamoxifen, reduce breast cancer risk by up to 50% in women at increased risk for breast cancer. Despite tamoxifen’s well-established efficacy, many studies show that most women are not taking up tamoxifen. This systematic literature review aimed to identify the motivators and barriers to tamoxifen use ‘s amongst high-risk women.

Methods

Using MEDLINE, PsycINFO, and Embase plus reviewing reference lists of relevant articles published between 1995 and 2016, 31 studies (published in 35 articles) were identified, which addressed high-risk women’s decisions about risk-reducing medication to prevent breast cancer and were peer-reviewed primary clinical studies.

Results

A range of factors were identified as motivators of, and barriers to, tamoxifen uptake including: perceived risk, breast-cancer-related anxiety, health professional recommendation, perceived drug effectiveness, concerns about side-effects, knowledge and access to information about side-effects, beliefs about the role of risk-reducing medication, provision of a biomarker, preference for other forms of breast cancer risk reduction, previous treatment experience, concerns about randomization in clinical trial protocols and finally altruism.

Conclusions

Results indicate that the decision for high-risk women regarding tamoxifen use or non-use as a risk-reducing medication is not straightforward. Support of women making this decision is essential and needs to encompass the full range of factors, both informational and psychological.

Tamoxifen Acceptance and Adherence among Patients with Ductal Carcinoma In Situ (DCIS) Treated in a Multidisciplinary Setting

Tamoxifen and other endocrine agents have proven benefits for women with ductal carcinoma in situ (DCIS), but low patient acceptance is widely reported. We examined factors associated with tamoxifen acceptance and adherence among DCIS patients who received a recommendation for therapy in a multidisciplinary setting. Using our institutional database, we identified women diagnosed with DCIS, 1998 to 2009, who were offered tamoxifen. We recorded data on demographics, tumor and therapy variables, tamoxifen acceptance, and adherence to therapy for ≥4 years. Univariable and multivariable analyses were conducted using logistic regression to identify factors specific to each group that were related to acceptance and adherence. A total of 555 eligible women identified, of whom 369 were offered tamoxifen; 298 (81%) accepted, among whom 214 (72%) were adherent, 59 of 298 (20%) were nonadherent, and for 25 (8%), adherence was undetermined. After stepwise elimination in adjusted logistic regression models, acceptance of breast radiotherapy was associated with acceptance of tamoxifen [OR, 2.22; 95% confidence interval (CI), 1.26-3.90; P < 0.01], as was a medical oncology consultation (OR, 1.76; 95% CI, 0.99-3.15; P = 0.05). Insured patients were more likely to adhere to tamoxifen (OR, 6.03; 95% CI, 2.60-13.98; P < 0.01). The majority of nonadherent women (n = 38/56, 68%) discontinued the drug during the first year of treatment with 48 (86%) citing adverse effect(s) as the reason. In a multidisciplinary, tertiary care setting, we observed relatively high rates of acceptance and adherence of tamoxifen. Acceptance of tamoxifen and radiotherapy were associated, and adherence was influenced by insurance status.Key Message: Tamoxifen acceptance and adherence following resection of DCIS of the breast is related to acceptance of radiotherapy and may be improved by confirmation of the recommendation by a medical oncologist. Despite the low cost of tamoxifen, adherence to therapy is significantly impacted by lack of insurance; those who discontinue therapy report adverse effects as a major reason. Cancer Prev Res; 10(7); 389-97. ©2017 AACR.

How do we increase uptake of tamoxifen and other anti-estrogens for breast cancer prevention?

Several randomized controlled trials of anti-estrogens, such as tamoxifen and aromatase inhibitors, have demonstrated up to a 50–65% decrease in breast cancerincidence among high-risk women. Approximately 15% of women, age 35–79 years, in the U.S. meet criteria for breast cancer preventive therapies, but uptake of these medications remain low. Explanations for this low uptake includelack of awareness of breast cancer risk status, insufficient knowledge about breast cancer preventive therapies among patients and physicians, and toxicity concerns. Increasing acceptance of pharmacologic breast cancer prevention will require effective communication of breast cancer risk, accurate representation about the potential benefits and side effects of anti-estrogens, targeting-specific high-risk populations most likely to benefit from preventive therapy, and minimizing the side effects of current anti-estrogens with novel administration and dosing options. One strategy to improve the uptake of chemoprevention strategies is to consider lessons learned from the use of drugs to prevent other chronic conditions, such as cardiovascular disease. Enhancing uptake and adherence to anti-estrogens for primary prevention holds promise for significantly reducing breast cancer incidence, however, this will require a significant change in our current clinical practice and stronger advocacy and awareness at the national level.

Aromatase expression in atypical ductal hyperplasia in women

PURPOSE

To determine the levels of aromatase in atypical ductal hyperplasia (ADH) lesions, tissue surrounding the ADH, and in dense and non-dense normal breast tissue. We postulated that excess aromatase in breast tissue might, through production of increased estrogen, drive the carcinogenic process. Estrogens and their metabolites are thought to contribute to the development of breast cancer through estrogen receptor-mediated mechanisms and genotoxic effects of estrogen metabolites. ADH is a benign lesion of the breast which is associated with substantially increased risk for subsequent development of breast cancer. After 25 years, approximately 30% of women with ADH develop breast cancer. In women with three or more separate ADH lesions at the same time, 47% will develop breast cancer over that time period. Another important risk factor for breast cancer is the presence of mammographically dense breast tissue.

METHODS

We utilized quantitative immunochemical analysis of aromatase in biopsy tissue to test this possibility. Previously published results comparing dense with non-dense breast tissue in normal women (Vachon et al. Breast Cancer Res Treat 125:243-252, 2011) were used for comparisons with ADH. A well-characterized histochemical H-score was employed for quantitative assessment of aromatase in the various tissue studied.

RESULTS

The H-score of aromatase staining was statistically significantly higher (p = 0.003) in the ADH epithelium than surrounding epithelial tissue. In order of H-score from highest to lowest were ADH, issue surrounding ADH, dense normal and non-dense normal breast tissues. The levels of aromatase in a subset of women with ADH who went on to develop breast cancer were not higher than in women who did not.

CONCLUSIONS

We suggest from these studies that overexpression of aromatase in breast tissue and its resultant increase in estradiol levels may contribute to the later development of breast cancer in women with ADH.

Polymeric micelles of amphiphilic graft copolymer of α-tocopherol succinate-g-carboxymethyl chitosan for tamoxifen delivery: Synthesis, characterization and in vivo pharmacokinetic study

Novel amphiphilic graft copolymers were prepared from low molecular weight carboxymethyl chitosan (LMW Cmc) and α-tocopherol succinate (TS) via an amidation reaction and confirmed by (1)H NMR and IR spectroscopy. These graft copolymers are self-assembled to nanosized core-shell-structural micelles in an aqueous milieu. The critical micelle concentration (CMC) decreased with an increasing substitution of TS on LMW Cmc, which ranged from 7.94×10(-8) to 1.58×10(-6)g/mL. Cmc-TS4.5 (Cmc-TS with a charged molar ratio of TS to glucosamine units of Cmc∼4.5) was shown maximum TMX loading up to 8.08±0.98%. Both blank and TMX-loaded PM's of Cmc-TS4.5 exhibit spherical shape with particle size below 200nm. An in vitro release study in simulated gastric and intestinal fluid demonstrated that TMX release from TMX-PM4.5 (TMX-PMs prepared with amphiphilic polymer Cmc-TS4.5, and the weight ratio of Cmc-TS4.5 to TMX was 8:1) was slow and pH dependent. In vivo oral absorption study revealed Cmc-TS4.5 based PM's permeated the epithelial barrier via the paracellular route without causing any intestinal damage. In vivo toxicity study demonstrated the safety of PM's after oral administration. Compared to tamoxifen control, TMX-PM4.5 dosed to fasted female Sprague Dawley rats showed a 1.9 fold increase in AUC0-72h. Thus, the results suggested that Cmc-TS micelles are a promising carrier for TMX delivery.

Chemoprevention for breast cancer: overcoming barriers to treatment

Evidence from placebo-controlled, randomized clinical trials supports the use of chemoprevention in women at high risk for developing breast cancer, and two agents-tamoxifen and raloxifene-are U.S. Food and Drug Administration (FDA)-approved for the indication. Despite clinical guidelines that recommend physicians counsel high-risk women about the use of chemoprevention and the estimated 2.4 million women in the United States who meet eligibility criteria for net benefit, the uptake of breast cancer chemoprevention has been exceedingly low. Assessments of the risks and benefits of chemoprevention are aided by the availability of models that can be used to estimate of the risk-benefit ratio. However, many physicians remain unaware of these resources to determine patient eligibility for chemoprevention and lack the time to provide informed counseling to their patients. The barriers for patients' acceptance of chemoprevention treatment include fear of side effects and the perception that chemoprevention will not substantially lower their risk of developing breast cancer. Despite these challenges, there are substantial opportunities to increase the utilization of chemoprevention. These strategies include education, dissemination of user-friendly risk-benefit models, and the support of research efforts focused on identifying biomarkers that can more accurately select women most likely to develop breast cancer and predict responsiveness of treatment.

Factors affecting uptake and adherence to breast cancer chemoprevention: a systematic review and meta-analysis

BACKGROUND

Preventive therapy is a risk reduction option for women who have an increased risk of breast cancer. The effectiveness of preventive therapy to reduce breast cancer incidence depends on adequate levels of uptake and adherence to therapy. We aimed to systematically review articles reporting uptake and adherence to therapeutic agents to prevent breast cancer among women at increased risk, and identify the psychological, clinical and demographic factors affecting these outcomes.

DESIGN

Searches were carried out in PubMed, CINAHL, EMBASE and PsychInfo, yielding 3851 unique articles. Title, abstract and full text screening left 53 articles, and a further 4 studies were identified from reference lists, giving a total of 57. This review was prospectively registered with PROSPERO (CRD42014014957).

RESULTS

Twenty-four articles reporting 26 studies of uptake in 21 423 women were included in a meta-analysis. The pooled uptake estimate was 16.3% [95% confidence interval (CI) 13.6-19.0], with high heterogeneity (I(2) = 98.9%, P < 0.001). Uptake was unaffected by study location or agent, but was significantly higher in trials [25.2% (95% CI 18.3-32.2)] than in non-trial settings [8.7% (95% CI 6.8-10.9)] (P < 0.001). Factors associated with higher uptake included having an abnormal biopsy, a physician recommendation, higher objective risk, fewer side-effect or trial concerns, and older age. Adherence (day-to-day use or persistence) over the first year was adequate. However, only one study reported a persistence of ≥ 80% by 5 years. Factors associated with lower adherence included allocation to tamoxifen (versus placebo or raloxifene), depression, smoking and older age. Risk of breast cancer was discussed in all qualitative studies.

CONCLUSION

Uptake of therapeutic agents for the prevention of breast cancer is low, and long-term persistence is often insufficient for women to experience the full preventive effect. Uptake is higher in trials, suggesting further work should focus on implementing preventive therapy within routine care.

Addressing barriers to uptake of breast cancer chemoprevention for patients and providers

Breast cancer is the most common malignancy among women in the United States, and the primary prevention of this disease is a major public health issue. Because there are relatively few modifiable breast cancer risk factors, pharmacologic interventions with antiestrogens have the potential to significantly affect the primary prevention setting. Breast cancer chemoprevention with selective estrogen receptor modulators (SERMs) tamoxifen and raloxifene, and with aromatase inhibitors (AIs) exemestane and anastrozole, is underutilized despite several randomized controlled trials demonstrating up to a 50% to 65% relative risk reduction in breast cancer incidence among women at high risk. An estimated 10 million women in the United States meet high-risk criteria for breast cancer and are potentially eligible for chemoprevention, but less than 5% of women at high risk who are offered antiestrogens for primary prevention agree to take it. Reasons for low chemoprevention uptake include lack of routine breast cancer risk assessment in primary care, inadequate time for counseling, insufficient knowledge about antiestrogens among patients and providers, and concerns about side effects. Interventions designed to increase chemoprevention uptake, such as decision aids and incorporating breast cancer risk assessment into clinical practice, have met with limited success. Clinicians can help women make informed decisions about chemoprevention by effectively communicating breast cancer risk and enhancing knowledge about the risks and benefits of antiestrogens. Widespread adoption of chemoprevention will require a major paradigm shift in clinical practice for primary care providers (PCPs). However, enhancing uptake and adherence to breast cancer chemoprevention holds promise for reducing the public health burden of this disease.

Decision making in the context of breast cancer chemoprevention: patient perceptions and the meaning of risk

Chemoprevention with selective estrogen receptor modulators (SERMs) is considered one of the most promising risk reduction options to date in the United States. Tamoxifen and raloxifene are both approved by the U.S. Food and Drug Administration (FDA) for breast cancer risk reduction. However, despite endorsement from the American Society for Clinical Oncology and the National Comprehensive Cancer Network, uptake remains low. Decision aids have been successful in improving women's understanding and knowledge about the risk-benefit trade-offs in decision making regarding SERMs. However, increased knowledge does not lead to increased uptake of chemoprevention for the purpose of reducing breast cancer risk; instead, women become more reluctant to take medication that is itself associated with risks. Reasons for this include a lack of awareness that SERMs are effective in reducing breast cancer risk, an unwillingness to increase the risk of other disease, reluctance to take a daily medication, and the perception of tamoxifen as a "cancer drug." In studies on hypothetical decision making in the context of chemoprevention women indicate greater willingness to take a SERM when they are determined to be at risk. These findings suggest a differential understanding of what risk means among the general public, health professionals, and researchers. Feeling at risk is related to bodily signs and symptoms and not to population-derived probabilities. Such differential understanding may in part explain women's perception of the low efficacy of SERMs and their decision making regarding SERM use.

Awareness of preventive medication among women at high risk for breast cancer and their willingness to consider transdermal or oral tamoxifen: a focus group study

Background

Despite demonstrated efficacy, acceptance of selective estrogen receptor modulators (SERMs), such as tamoxifen, for breast cancer risk reduction remains low. Delivering SERMs via local transdermal therapy (LTT) could significantly reduce systemic effects and therefore may increase acceptance. We aim to assess women’s knowledge of breast cancer prevention medications and views on LTT of SERMs.

Methods

Focus groups were conducted with healthy women identified through the comprehensive breast center of a large urban cancer institution. Group discussions covered risk perceptions, knowledge of and concerns about risk reducing medications. Participants reported their perceived risk for breast cancer (average, below/above average), preference for SERMs in a pill or gel form, risk factors, and prior physician recommendations regarding risk-reducing medicines. Participants’ breast cancer risk was estimated using tools based on the Gail Model. Trained personnel examined all qualitative results systematically; risk perceptions and preferred method of medication delivery were tallied quantitatively.

Results

Four focus groups (N = 32) were conducted. Most participants had at least a college degree (78.2 %) and were of European (50 %) or African ancestry (31 %). The majority (72 %) were at elevated risk for breast cancer; approximately half of these women perceived themselves to be at elevated risk. Few participants had prior knowledge of preventive medications. The women noted a number of concerns about LTT, including dosage, impact on day-to-day life, and side effects; nonetheless, over 90 % of the women stated they would prefer LTT to a pill.

Conclusion

Awareness of preventive medications was low even in a highly educated sample of high-risk women. If given a choice in the route of administration, most women preferred a gel to a pill, anticipating fewer side effects. Future work should focus on demonstrating equivalent efficacy and reduced toxicity of topical over oral medications and on raising awareness of chemopreventive options for breast cancer.

Alternate dosing schedules for cancer chemopreventive agents

Pharmacologic interventions for cancer risk reduction involve the chronic administration of synthetic or natural agents to reduce or delay the occurrence of malignancy. Despite the strong evidence for a favorable risk-benefit ratio for a number of agents in several common malignancies such as breast and prostate cancer, the public's attitude toward cancer chemoprevention remains ambivalent, with the issue of toxicity associated with drugs being perceived as the main barrier to widespread use of preventive therapy by high-risk subjects. Among the strategies to overcome such obstacles to preventive therapies, two novel and potentially safer modes of administering agents are discussed in this paper. The first strategy is to lower the dose of drugs that are in common use in the adjuvant setting based on the notion that prevention of cancer cells from developing should require a lower dose than eradicating established tumor cells. A second approach is to adopt an intermittent administration similar to what is used in the chemotherapy setting in an attempt to minimize risks while retaining benefits. This article provides a detailed discussion of the principles and future development of these two approaches in the direction of a precision preventive medicine.

Breast Cancer Chemoprevention among High-risk Women and those with Ductal Carcinoma In Situ

Chemoprevention with the anti-estrogens, tamoxifen, raloxifene, and aromatase inhibitors, reduce breast cancer incidence in high-risk women; however, uptake has been poor (<5%) in the prevention setting. We assessed use of anti-estrogens for breast cancer prevention, among high-risk women seen at an academic breast center, to observe how uptake rates compare in this setting. We collected data on demographics, breast cancer risk factors, and health behaviors via self-administered questionnaires and medical chart abstraction. Women eligible for chemoprevention with anti-estrogens had a 5-year predicted breast cancer risk according to the Gail model of ≥1.67%, history of lobular or ductal carcinoma in situ (LCIS/DCIS), and/or BRCA mutation. We dichotomized anti-estrogen use as ever or never. Predictors of use were evaluated using multivariable log-binomial regression. Of 412 high-risk women enrolled, 316 (77%) were eligible for chemoprevention. Among eligible women, 55% were non-Hispanic white, 29% Hispanic, 8% non-Hispanic black, and 7% Asian. Women were grouped based upon their highest category of breast cancer risk (in descending order): BRCA mutation carriers (3%), DCIS (40%), LCIS (22%), and 5-year Gail risk ≥1.67% (36%). Among those eligible for chemoprevention, 162 (51%) had ever initiated anti-estrogen therapy (71% tamoxifen, 23% raloxifene, 5% aromatase inhibitor). Anti-estrogen use was highest among women with DCIS (73%). In multivariable analysis, women with a 5-year Gail risk ≥1.67% had approximately a 20% lower likelihood of anti-estrogen use compared to women with DCIS (p = 0.01). In the primary prevention setting, excluding women diagnosed with DCIS, anti-estrogen use was 37%. Multivariable analysis showed differences in uptake by education and potentially by race/ethnicity. Among high-risk women seen at a breast center, anti-estrogen use for chemoprevention was relatively high as compared to the published literature. Clinicians can support high-risk women by effectively communicating breast cancer risk and enhancing knowledge about the risks and benefits of chemoprevention.

Risk-benefit profiles of women using tamoxifen for chemoprevention

BACKGROUND

Tamoxifen has been US Food and Drug Administration-approved for primary prevention of breast cancer since 1998 but has not been widely adopted, in part because of increased risk of serious side effects. Little is known about the risk-benefit profiles of women who use chemoprevention outside of a clinical trial. We examined characteristics associated with initiation and discontinuation of tamoxifen for primary prevention of breast cancer within a large cohort of women with a first-degree family history of breast cancer.

METHODS

This research was conducted within The Sister Study, a cohort of 50884 US and Puerto Rican women age 35 to 74 years enrolled from 2003 to 2009. Eligible women were breast cancer-free at enrollment and had a sister who had been diagnosed with breast cancer. Participants reported tamoxifen use, ages started and stopped taking tamoxifen, and total duration of use at enrollment. We identified 788 tamoxifen users and 3131 nonusers matched on age and year of enrollment who had no history of contraindicating factors (stroke, transient ischemic attack, cataract, endometrial or uterine cancer). Characteristics associated with tamoxifen initiation were evaluated with multivariable conditional logistic regression. All statistical tests were two-sided.

RESULTS

Based on published risk-benefit indices, 20% of women who used tamoxifen had insufficient evidence that the benefits of tamoxifen outweigh the risk of serious side effects. After 4.5 years, 46% of women had discontinued tamoxifen.

CONCLUSIONS

While the majority of women who used tamoxifen for primary prevention of breast cancer were likely to benefit, substantial discontinuation of tamoxifen before five years and use by women at risk of serious side effects may attenuate benefits for breast cancer prevention.

A randomized phase II presurgical trial of transdermal 4-hydroxytamoxifen gel versus oral tamoxifen in women with ductal carcinoma in situ of the breast

PURPOSE

Local transdermal therapy to the breast may achieve effective target-organ drug delivery, while diminishing systemic effects. We conducted a randomized, double-blind, placebo-controlled phase II trial comparing transdermal 4-hydroxytamoxifen gel (4-OHT) to oral tamoxifen (oral-T) in women with ductal carcinoma in situ (DCIS).

METHODS

Twenty-seven pre- and postmenopausal women were randomized to 4-OHT (4 mg/day) or oral-T (20 mg/day) for 6 to 10 weeks before surgery. Plasma, nipple aspirate fluid, and breast adipose tissue concentrations of tamoxifen and its major metabolites were determined by liquid chromatography/tandem mass spectrometry. The primary endpoint was Ki67 labeling in DCIS lesions, measured by immunohistochemistry. In plasma, insulin-like growth factor-1 (IGFI), sex hormone-binding globulin (SHBG), and coagulation protein concentrations were determined.

RESULTS

Posttherapy Ki67 decreased by 3.4% in the 4-OHT and 5.1% in the oral-T group (P ≤ 0.03 in both, between-group P = 0. 99). Mean plasma 4-OHT was 0.2 and 1.1 ng/mL in 4-OHT and oral groups, respectively (P = 0.0003), whereas mean breast adipose tissue concentrations of 4-OHT were 5.8 ng/g in the 4-OHT group and 5.4 ng/g in the oral group (P = 0.88). There were significant increases in plasma SHBG, factor VIII, and von Willebrand factor and a significant decrease in plasma IGFI with oral-T, but not with 4-OHT. The incidence of hot flashes was similar in both groups.

CONCLUSIONS

The antiproliferative effect of 4-OHT gel applied to breast skin was similar to that of oral-T, but effects on endocrine and coagulation parameters were reduced. These findings support the further evaluation of local transdermal therapy for DCIS and breast cancer prevention.

Women's preferences for selective estrogen reuptake modulators: an investigation using protection motivation theory

OBJECTIVE

Selective estrogen receptor modulators (SERMs) reduce breast cancer risk by 38%. However, uptake is low and the reasons are not well understood. This study applied protection motivation theory (PMT) to determine factors associated with intention to take SERMs.

METHODS

Women at increased risk of breast cancer (N=107), recruited from two familial cancer clinics in Australia, completed a questionnaire containing measures of PMT constructs. Hierarchical multiple linear regression analysis was used to analyze the data.

RESULTS

Forty-five percent of women said they would be likely or very likely to take SERMs in the future. PMT components accounted for 40% of variance in intention to take SERMs. Perceived vulnerability, severity and response efficacy appeared the most influential in women's decisions to take or not take SERMs.

CONCLUSION

Many women are interested in SERMs as a risk management option. Accurate risk estimation and an understanding of the benefits of SERMs are critical to women's decision making.

PRACTICE IMPLICATIONS

Health professionals need to explore women's perceptions of their risk and its consequences, as well as providing clear evidence-based information about the efficacy of SERMs. Exploring the source and strength of beliefs about SERMs may allow more effective, tailored counseling.

Women's preferences for selective estrogen reuptake modulators: an investigation using the time trade-off technique

Purpose

Selective Estrogen Receptor Modulators (SERMs) reduce the risk of breast cancer for women at increased risk by 38%. However, uptake is extremely low and the reasons for this are not completely understood. The aims of this study were to utilize time trade-off methods to determine the degree of risk reduction required to make taking SERMs worthwhile to women, and the factors associated with requiring greater risk reduction to take SERMs.

Methods

Women at increased risk of breast cancer (N = 107) were recruited from two familial cancer clinics in Australia. Participants completed a questionnaire either online or in pen and paper format. Hierarchical multiple linear regression analysis was used to analyze the data.

Results

Overall, there was considerable heterogeneity in the degree of risk reduction required to make taking SERMs worthwhile. Women with higher perceived breast cancer risk and those with stronger intentions to undergo (or who had undergone) an oophorectomy required a smaller degree of risk reduction to consider taking SERMs worthwhile.

Conclusion

Women at increased familial risk appear motivated to consider SERMs for prevention. A tailored approach to communicating about medical prevention is essential. Health professionals could usefully highlight the absolute (rather than relative) probability of side effects and take into account an individual’s perceived (rather than objective) risk of breast cancer.

Uptake of tamoxifen in consecutive premenopausal women under surveillance in a high-risk breast cancer clinic

BACKGROUND

Randomised trials of tamoxifen versus placebo indicate that tamoxifen reduces breast cancer risk by approximately 33%, yet uptake is low. Approximately 10% of women in our clinic entered the IBIS-I prevention trial. We assess the uptake of tamoxifen in a consecutive series of premenopausal women not in a trial and explore the reasons for uptake through interviews.

METHODS

All eligible women between 33 and 46 years at ≥17% lifetime risk of breast cancer and undergoing annual mammography in our service were invited to take a 5-year course of tamoxifen. Reasons for accepting (n=15) or declining (n=15) were explored using semi-structured interviews.

RESULTS

Of 1279 eligible women, 136 (10.6%) decided to take tamoxifen. Women >40 years (74 out of 553 (13.4%)) and those at higher non-BRCA-associated risk were more likely to accept tamoxifen (129 out of 1109 (11.6%)). Interviews highlighted four themes surrounding decision making: perceived impact of side effects, the impact of others' experience on beliefs about tamoxifen, tamoxifen as a 'cancer drug', and daily reminder of cancer risk.

CONCLUSIONS

Tamoxifen uptake was similar to previously ascertained uptake in a randomised controlled trial (IBIS-I). Concerns were similar in women who did or did not accept tamoxifen. Decision making appeared to be embedded in the experience of significant others.

Chemoprevention of Breast Cancer: The Paradox of Evidence versus Advocacy Inaction

Women who are at high risk of breast cancer can be offered chemoprevention. Chemoprevention strategies have expanded over the past decade and include selective receptor modulator inhibitors and aromatase inhibitors. Physicians are expected to provide individualized risk assessments to identify high risk women who may be eligible for chemoprevention. It is prudent that physicians utilize a shared decision approach when counseling high risk women about their preventive options. Barriers and misperceptions however exist with patient and physician acceptance of chemoprevention and continue to impede uptake of chemoprevention as a strategy to reduce breast cancer risk. Programs to increase awareness and elucidate the barriers are critical for women to engage in cancer prevention and promote chemoprevention adherence.

Oral low dose and topical tamoxifen for breast cancer prevention: modern approaches for an old drug

Tamoxifen is a drug that has been in worldwide use for the treatment of estrogen receptor (ER)-positive breast cancer for over 30 years; it has been used in both the metastatic and adjuvant settings. Tamoxifen's approval for breast cancer risk reduction dates back to 1998, after results from the Breast Cancer Prevention Trial, co-sponsored by the National Cancer Institute and the National Surgical Adjuvant Breast and Bowel Project, showed a 49% reduction in the incidence of invasive, ER-positive breast cancer in high-risk women. Despite these positive findings, however, the public's attitude toward breast cancer chemoprevention remains ambivalent, and the toxicities associated with tamoxifen, particularly endometrial cancer and thromboembolic events, have hampered the drug's uptake by high-risk women who should benefit from its preventive effects. Among the strategies to overcome such obstacles to preventive tamoxifen, two novel and potentially safer modes of delivery of this agent are discussed in this paper. Low-dose tamoxifen, expected to confer fewer adverse events, is being investigated in both clinical biomarker-based trials and observational studies. A series of systemic biomarkers (including lipid and insulin-like growth factor levels) and tissue biomarkers (including Ki-67) are known to be favorably affected by conventional tamoxifen dosing and have been shown to be modulated in a direction consistent with a putative anti-cancer effect. These findings suggest possible beneficial clinical preventive effects by low-dose tamoxifen regimens and they are supported by observational studies. An alternative approach is topical administration of active tamoxifen metabolites directly onto the breast, the site where the cancer is to be prevented. Avoidance of systemic administration is expected to reduce the distribution of drug to tissues susceptible to tamoxifen-induced toxicity. Clinical trials of topical tamoxifen with biological endpoints are still ongoing whereas pharmacokinetic studies have already shown that appropriate formulations of drug successfully penetrate the skin to reach breast tissue, where a preventive effect is sought.

Willingness to use tamoxifen to prevent breast cancer among diverse women

Use of chemoprevention to prevent development of breast cancer among high-risk women has been limited despite clinical evidence of its benefit. Our goals were to determine whether knowledge of the benefits and risks of tamoxifen affects a woman's willingness to take it to prevent breast cancer, to define factors associated with willingness to take tamoxifen, and to evaluate race/ethnic differences. Women, ages 50-80, who identified as African American, Asian, Latina, or White, and who had at least one visit to a primary care physician in the previous 2 years, were recruited from ambulatory practices. After a screening telephone survey, women completed an in-person interview in their preferred language. Multivariate regression models were constructed to examine the associations of demographic characteristics, numeracy, breast cancer history, and health knowledge with willingness to take tamoxifen. Over 40% of the women reported they would likely take tamoxifen if determined to be at high risk, and 31% would be somewhat likely to do so. Asian women, those with no insurance, and those with less than high school education were significantly more likely to be willing to take tamoxifen. Higher scores on numeracy and on breast cancer knowledge were also associated with willingness to take tamoxifen. A higher tamoxifen knowledge score was inversely related to willingness to take the drug. Factors affecting women's willingness to take breast cancer chemoprevention drugs vary and are not determined solely by knowledge of risk/benefit or risk perception.

Tamoxifen vs Raloxifene vs Exemestane for Chemoprevention

Clinical trial data on selective estrogen receptor modulators (SERMs) and aromatase inhibitors (AIs) have demonstrated reduced breast cancer incidence in the prevention setting among high-risk women. We conducted an extensive review of clinical trials and recent published reports of barriers to uptake of breast cancer chemoprevention, to provide health care professionals with information to improve decision-making regarding chemoprevention. Despite the positive results of these trials, uptake of chemoprevention has been low due to barriers in identifying high-risk women, lack of understanding of risks and benefits, as well as concerns about side effects. Interventions designed to increase uptake have met with limited success. Clinicians can support women in informed decision-making about SERMs and AIs by effectively communicating breast cancer risk and enhancing knowledge about the risks and benefits of chemoprevention. Promoting uptake and adherence to chemoprevention holds promise for reducing the public health burden of this disease.

Breast-specific gamma imaging in the detection of atypical ductal hyperplasia and lobular neoplasia

RATIONALE AND OBJECTIVES

Atypical lesions such as atypical ductal hyperplasia (ADH) and lobular neoplasia are nonmalignant lesions that are associated with significant increased risk of developing breast cancer. Atypical lesions have been reported to present with focal increased radiotracer uptake on breast-specific gamma imaging (BSGI) examination, a novel physiologic tool for the detection of breast cancer. To date the sensitivity of BSGI in the detection of atypical lesions has not been reported. The purpose of this study is to determine the sensitivity of BSGI in detecting ADH and lobular neoplasia.

MATERIALS AND METHODS

A total of 1316 patients who received a BSGI exam between January 2006 and July 2009 were retrospectively reviewed. All patients who underwent minimally invasive biopsy and subsequent surgical excision where the highest pathology was solely ADH or lobular neoplasia (reported as ALH, lobular carcinoma in situ or lobular neoplasia), according to the pathology database were included (n = 15). The sensitivity was determined as the percentage of positive BSGI exams out of all patients diagnosed with ADH or lobular neoplasia who received a BSGI.

RESULTS

Patient ages ranged from 39 to 67 (mean, 52). Eight of 15 patients had ADH, 6/15 lobular neoplasia, and 1/15 ADH and lobular neoplasia in one lesion. Fifteen of the 15 (100%) patients with surgically confirmed ADH or lobular neoplasia had a positive BSGI, with focally increased radiotracer uptake at the site of the verified high-risk lesion.

CONCLUSION

BSGI has a high sensitivity for the detection of atypical, high-risk breast lesions. A diagnosis of an atypical lesion is concordant with focal increased radiotracer uptake with BSGI and can identify women at increased risk for breast cancer.

Could NSAIDs become a preventative therapy in pregnancy-associated breast cancer?

SUMMARY Pregnancy-associated breast cancer (PABC) is a unique type of young women’s breast cancer that includes two biologically distinct conditions: those diagnosed during pregnancy and those diagnosed postpartum. It is the dominant subset of postpartum PABC that is more consistently associated with higher breast cancer mortality. Preclinical work has identified the normal event of postpartum involution as a wound-healing milieu rich in immune cells. We have shown that the involution environment drives tumor growth, proliferation and metastasis. Moreover, we have demonstrated in animal models that this ‘involution effect’ can be abrogated with drug therapy, namely NSAIDs, which target normal involution pathways implicated in PABC tumor promotion. In this perspective, we review the contemporary understanding of PABC, our preclinical modeling and its implications and the unmet research needs required for future translation of these preclinical studies into rational and safe human clinical trials.

Soy isoflavone supplementation for breast cancer risk reduction: a randomized phase II trial

Soy isoflavone consumption may protect against breast cancer development. We conducted a phase IIB trial of soy isoflavone supplementation to examine its effect on breast epithelial proliferation and other biomarkers in the healthy high-risk breast. One hundred and twenty-six consented women underwent a random fine-needle aspiration (rFNA); those with 4,000 or more epithelial cells were randomized to a double-blind 6-month intervention of mixed soy isoflavones (PTIG-2535) or placebo, followed by repeat rFNA. Cells were examined for Ki-67 labeling index and atypia. Expression of 28 genes related to proliferation, apoptosis, and estrogenic effect was measured using quantitative reverse transcriptase PCR. Hormone and protein levels were measured in nipple aspirate fluid (NAF). All statistical tests were two-sided. Ninety-eight women were evaluable for Ki-67 labeling index. In 49 treated women, the median Ki-67 labeling index was 1.18 at entry and 1.12 post intervention, whereas in 49 placebo subjects, it was 0.97 and 0.92 (P for between-group change: 0.32). Menopausal stratification yielded similar results between groups, but within premenopausal soy-treated women, Ki-67 labeling index increased from 1.71 to 2.18 (P = 0.04). We saw no treatment effect on cytologic atypia or NAF parameters. There were significant increases in the expression of 14 of 28 genes within the soy, but not the control group, without significant between-group differences. Plasma genistein values showed excellent compliance. A 6-month intervention of mixed soy isoflavones in healthy, high-risk adult Western women did not reduce breast epithelial proliferation, suggesting a lack of efficacy for breast cancer prevention and a possible adverse effect in premenopausal women.

Recruitment to a physical activity intervention study in women at increased risk of breast cancer

Background

Physical activity is being studied as a breast cancer prevention strategy. Women at risk of breast cancer report interest in lifestyle modification, but recruitment to randomized physical activity intervention studies is challenging.

Methods

We conducted an analysis of recruitment techniques used for a prospective, randomized pilot study of physical activity in women at risk of breast cancer. We evaluated differences in proportion of eligible patients, enrolled patients, and successful patients identified by each individual recruitment method. The Fisher-Freeman-Halton test (an extension of Fisher's exact test from 2 × 2 tables to general row by column tables) was used to compare the success of different recruitment strategies.

Results

We received 352 inquiries from women interested in participating, of whom 171 (54%) were eligible. Ninety-nine women completed a baseline activity evaluation, and 58 (34% of eligible; 16% of total inquiries) were randomized. Recruitment methods fell into three broad categories: media techniques, direct contact with potential participants, and contacts with health care providers. Recruitment strategies differed significantly in their ability to identify eligible women (p = 0.01), and women who subsequently enrolled in the study (p = 0.02).

Conclusion

Recruitment techniques had varying success. Our data illustrate the challenges in recruiting to behavior modification studies, and provide useful information for tailoring future recruitment efforts for lifestyle intervention trials.

Trial Registration No(s)

CDR0000393790, NCI-04-C-0276, NCI-NAVY-B05-001

Using clinical factors and mammographic breast density to estimate breast cancer risk: development and validation of a new predictive model

BACKGROUND

Current models for assessing breast cancer risk are complex and do not include breast density, a strong risk factor for breast cancer that is routinely reported with mammography.

OBJECTIVE

To develop and validate an easy-to-use breast cancer risk prediction model that includes breast density.

DESIGN

Empirical model based on Surveillance, Epidemiology, and End Results incidence, and relative hazards from a prospective cohort.

SETTING

Screening mammography sites participating in the Breast Cancer Surveillance Consortium.

PATIENTS

1,095,484 women undergoing mammography who had no previous diagnosis of breast cancer.

MEASUREMENTS

Self-reported age, race or ethnicity, family history of breast cancer, and history of breast biopsy. Community radiologists rated breast density by using 4 Breast Imaging Reporting and Data System categories.

RESULTS

During 5.3 years of follow-up, invasive breast cancer was diagnosed in 14,766 women. The breast density model was well calibrated overall (expected-observed ratio, 1.03 [95% CI, 0.99 to 1.06]) and in racial and ethnic subgroups. It had modest discriminatory accuracy (concordance index, 0.66 [CI, 0.65 to 0.67]). Women with low-density mammograms had 5-year risks less than 1.67% unless they had a family history of breast cancer and were older than age 65 years.

LIMITATION

The model has only modest ability to discriminate between women who will develop breast cancer and those who will not.

CONCLUSION

A breast cancer prediction model that incorporates routinely reported measures of breast density can estimate 5-year risk for invasive breast cancer. Its accuracy needs to be further evaluated in independent populations before it can be recommended for clinical use.

Atypia in random periareolar fine-needle aspiration affects the decision of women at high risk to take tamoxifen for breast cancer chemoprevention

Random periareolar fine-needle aspiration (RPFNA) is a research procedure designed to (a) evaluate short-term breast cancer risk in women at high risk for developing breast cancer, and (b) track response to chemoprevention. Of import, cellular atypia in breast RPFNA is prospectively associated with a 5.6-fold increase in breast cancer risk in women at high risk. Among 99 women attending a clinic for high-risk breast cancer, we explored the effects of RPFNA cytology results on decision making pertaining to the use of tamoxifen for breast cancer chemoprevention. No patient with nonproliferative or hyperplastic cytology subsequently elected to take tamoxifen. Only 7% of subjects with borderline atypia elected to take tamoxifen. In contrast, 50% with atypia elected to take tamoxifen. These results suggest that the provision of a biomarker of short-term risk can affect the motivation to take tamoxifen for chemoprevention. This conclusion is informative given that tamoxifen, due to its side effects, is often underused by women at high risk of developing breast cancer. Further research is needed to determine the mechanisms through which RPFNA results affect the decision to use tamoxifen, or any other breast cancer chemopreventive agent.

A role for biomarkers in the screening and diagnosis of breast cancer in younger women

The widespread usage of screening mammography has resulted in an increase in the detection of early-stage disease, particularly in situ (stage 0) and early-stage (stage 1) cancers. However, incidence of stage 2 and 3 disease has not fallen commensurately, suggesting a bias in the detection of indolent cancers rather than aggressive cancers. Improved screening and diagnosis of a broader range of cancers is therefore an important need. Although MRI is a very sensitive breast cancer detection tool that has become standard for women at very high risk, it lacks sufficient specificity and cost-effectiveness for use as a general screen. The greatest opportunity for molecular tools to improve breast cancer outcomes is to better discern biologically aggressive cancers, especially in women under the age of 50 years. In this age group, presentation in stage 2 or 3 is more common and mammographic screening is less efficacious. We propose a multi-tiered triage strategy that uses emerging markers of susceptibility to segment the population for more focused screening with imaging. In particular, it would be helpful to identify a subset of at-risk, younger women who would benefit from intensive surveillance or preventive interventions. It is likely that tests for susceptibility, unless they are highly specific, will need to be combined with indicators of short-term risk. Although the combined sensitivity and specificity of screening must be high, each individual test does not require high specificity. It is important, however, for the susceptibility tests and short-term risk markers to be highly sensitive. If the majority of women under 50 years of age who develop breast cancer are captured with this strategy, then mammography screening for the general population can start at age 50 years. Finally, and perhaps most importantly, biomarkers of susceptibility and short-term risk are likely to provide insight into the biology of tumors that develop, leading to new interventions to support prevention. The most effective preventive strategies will be those where a marker predicts risk for the disease, as well as the benefit from preventive interventions.

How should we inform women at higher risk of breast cancer about tamoxifen? An approach with a decision guide

BACKGROUND

Tamoxifen has been shown to reduce the incidence of invasive breast cancer in women at higher risk. Translating these research results to clinical practice is challenging. Our objective was to develop and evaluate a decision-making guide and process that can be used in clinical practice to inform eligible women of chemoprevention with tamoxifen.

METHODS

A decision guide explaining the benefits and risks of tamoxifen was developed with input from health care professionals and two focus groups of women both with and without cancer. Following consent, 51 eligible women presenting to a multi-disciplinary diagnostic facility for breast problems were given the decision guide/questionnaire to read, fill out and return by mail. Women with further questions or wanting to take tamoxifen were encouraged to re-contact their physicians.

RESULTS

Atypia was seen in 60% of subjects. Median 5-year Gail risk was 3.7 (range 1.7-9.4). Only 6 (11.8% 95% CI = 2.9, 20.6%) women reported they would like to take tamoxifen while 6 (11.8% 95% CI = 2.9, 20.6%) remained uncertain.

CONCLUSION

We have developed a decision-making guide and process that is acceptable to providers and women to identify and inform women at higher risk of breast cancer with regard to chemoprevention with tamoxifen. Few women in this select group, when provided with a balanced decision guide, wished to pursue chemoprevention with tamoxifen.

Regulation of intracellular calcium release and PP1α in a mechanism for 4-hydroxytamoxifen-induced cytotoxicity

Treatment with tamoxifen, or its metabolite 4-hydroxytamoxifen (4OHT), has cytostatic and cytotoxic effects on breast cancer cells in vivo and in culture. Although the effectiveness of 4OHT as an anti-breast cancer agent is due to its action as an estrogen receptor-alpha (ERalpha) antagonist, evidences show that 4OHT is also cytotoxic for ERalpha-negative breast cancer cells and can be effective therapy against tumors that lack estrogen receptors. These findings underscore 4OHT signaling complexities and belie the most basic understandings of 4OHT action and resistance. Here, we have investigated the effects of 4OHT on Ca2+ homeostasis and cell death in breast cancer cells in culture. Measurement of Ca2+ signaling in breast cancer cells showed that 4OHT treatment altered Ca2+ homeostasis and was cytotoxic for both an ERalpha+ and an ERalpha- cell line, MCF-7 and MDA-MB-231, respectively. Further investigation lead us to the novel discovery that 4OHT-induced increase of ATP-dependent Ca2+ release from the endoplasmic reticulum correlated with 4OHT-induced upregulation of protein phosphatase 1alpha (PP1alpha) and the inositol 1,4,5-trisphosphate receptor (IP3R). Blocking 4OHT-induced PP1alpha upregulation by siRNA strategy reduced the effects of 4OHT on both Ca2+ signaling and cytotoxicity. Results from these investigations strongly suggest a role for PP1alpha upregulation in a mechanism for 4OHT-induced changes to Ca2+ signaling that ultimately contribute to the cytotoxic effects of 4OHT.

Decision making in cancer primary prevention and chemoprevention

BACKGROUND

We know very little about how individuals decide to undertake, maintain, or discontinue cancer primary prevention or chemoprevention.

PURPOSE

The aims of this article are to (a) examine whether and, if so, how traditional health behavior change models are relevant for decision making in this area; (b) review the application of decision aids to forming specific, personal choices between options; and (c) identify the challenges of evaluating these decision processes to suggest areas for future research.

METHODS

Theoretical models and frameworks derived from the health behavior change and decision-making fields were applied to cancer primary prevention choices. Decision aids for the human papillomavirus (HPV) vaccine, Hormone Replacement Therapy (HRT), and tamoxifen were systematically examined.

RESULTS

Traditional concepts such as decisional balance and cues to action are relevant to understanding cancer primary prevention choices; Motivational Interviewing, Self-Determination Theory, and the Preventive Health Model may also explain the facilitators of decision making. There are no well-tested HPV vaccine decision aids, although there have been some studies on aids for HPV testing. There are several effective decision aids for HRT and tamoxifen; evidence-based decision aid components have also been identified.

CONCLUSIONS

Additional theory-based empirical research on decision making in cancer primary prevention and chemoprevention, particularly at the interface of psychology and behavioral economics, is suggested.