Psychological and clinical factors implicated in decision making about a trial of low-dose tamoxifen in hormone replacement therapy users

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.

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.

Aspirin use for cancer prevention: A systematic review of public, patient and healthcare provider attitudes and adherence behaviours

We undertook a systematic review to synthesise the data on attitudes and behaviour towards the use of aspirin for cancer prevention, and healthcare providers' attitudes towards implementing aspirin in practice. Searches were carried out across 12 databases (e.g. MEDLINE, EMBASE). We used the Mixed Methods Appraisal Tool to evaluate study quality, and conducted a narrative synthesis of the data. The review was pre-registered (PROSPERO: CRD42018093453). Thirty-eight studies were identified. Uptake and adherence data were all from trials. Trials recruited healthy participants, those at higher risk of cancer, and those with cancer. Four studies reported moderate to high (40.9-77.7%) uptake to an aspirin trial among people who were eligible. Most trials (18/22) reported high day-to-day adherence (≥80%). Three trials observed no association between gender and adherence. One trial found no association between adherence and colorectal cancer risk. Three studies reported moderate to high (43.6-76.0%) hypothetical willingness to use aspirin. Two studies found that a high proportion of healthcare providers (72.0-76.0%) perceived aspirin to be a suitable cancer prevention option. No qualitative studies were identified. The likelihood that eligible users of aspirin would participate in a trial evaluating the use of aspirin for preventive therapy was moderate to high. Among participants in a trial, day-to-day adherence was high. Further research is needed to identify uptake and adherence rates in routine care, the factors affecting aspirin use, and the barriers to implementing aspirin into clinical care.

Understanding low chemoprevention uptake by women at high risk of breast cancer: findings from a qualitative inductive study of women's risk-reduction experiences

BACKGROUND

Chemoprevention is one of several methods that have been developed to help high-risk women reduce their risk of breast cancer. Reasons for the low uptake of chemoprevention are poorly understood. This paper seeks a deeper understanding of this phenomenon by drawing on women's own narratives about their awareness of chemoprevention and their risk-related experiences.

METHODS

This research is based on a parent project that included fifty in-depth, semi-structured interviews with a purposive sample of African American and White women at elevated risk of breast cancer. This specific study draws on the forty-seven interviews conducted with women at high or severe risk of breast cancer, all of whom are eligible to use chemoprevention for breast cancer risk-reduction. Interviews were analyzed using grounded theory methods.

RESULTS

Forty-five percent of participants, and only 21% of African American participants, were aware of chemoprevention options. Women who had seen specialists were more likely to be aware, particularly if they had ongoing specialist access. Aware and unaware women relied on different types of sources for prevention-related information. Those whose main source of information was a healthcare provider were more likely to know about chemoprevention. Aware women used more nuanced information gathering strategies and worried more about cancer. Women simultaneously considered all risk-reduction options they knew about. Those who knew about chemoprevention but were reluctant to use it felt this way for multiple reasons, having to do with potential side effects, perceived extreme-ness of the intervention, similarity to chemotherapy, unknown information about chemoprevention, and reluctance to take medications in general.

CONCLUSIONS

Lack of chemoprevention awareness is a critical gap in women's ability to make health-protective choices. Future research in this field must consider complexities in both women's perspectives on chemoprevention and the reasons they are reluctant to use it.

Breast cancer worry in higher-risk women offered preventive therapy: a UK multicentre prospective study

Purpose

Women’s worry about developing breast cancer may influence their decision to use preventive therapy. However, the direction of this relationship has been questioned. We prospectively investigated the relationship between breast cancer worry and uptake of preventive therapy. The socio-demographic and clinical factors associated with high breast cancer worry were also investigated.

Methods

Women at increased risk of developing breast cancer were recruited from clinics across England (n = 408). Participants completed a survey on their breast cancer worry, socio-demographic and clinical factors. Uptake of tamoxifen was recorded at 3 months (n = 258 women, 63.2%). Both primary and sensitivity analyses were conducted using different classifications of low, medium and high worry.

Results

39.5% of respondents reported medium breast cancer worry at baseline and 21.2% reported high worry. Ethnic minority women were more likely to report high worry than white women (OR = 3.02, 95%CI 1.02, 8.91, p = 0.046). Women educated below degree level were more likely to report high worry than those with higher education (OR = 2.29, 95%CI 1.28, 4.09, p = 0.005). No statistically significant association was observed between worry and uptake. In the primary analysis, fewer respondents with medium worry at baseline initiated tamoxifen (low worry = 15.5%, medium = 13.5%, high = 15.7%). In the sensitivity analysis, participants with medium worry reported the highest uptake of tamoxifen (19.7%).

Conclusions

No association was observed between worry and uptake, although the relationship was affected by the categorisation of worry. Standardised reporting of the classification of worry is warranted to allow transparent comparisons across cohorts.

Supplementary Information

The online version contains supplementary material available at 10.1007/s10549-021-06183-x.

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.

Women's perceptions of the adoption of personalised risk-based breast cancer screening and primary prevention: a systematic review

INTRODUCTION

Increased knowledge of breast cancer risk factors may enable a paradigm shift from the current age-based mammographic screening programmes to a personalised risk-based approach. This would warrant a significant change in practice, yet the acceptability from a woman's perspective has never been systematically explored. In this systematic review, we inventoried and appraised studies of women's perceptions of risk-based breast cancer screening and prevention to identify factors associated with adopting this new paradigm.

METHODS

We searched Medline, Embase and PsycInfo to identify original articles in English containing perceptions of risk-based breast cancer screening and/or primary prevention of women with an average to above average risk of developing breast cancer. Qualitative data were systematically extracted and referenced against four theoretical models of preventative health behaviour adoption.

RESULTS

When considering the adoption of this novel screening and prevention programme, women carefully review their perceived susceptibility to breast cancer. Their decisions are based on a cost-benefit analysis of adopting lifestyle changes, chemoprevention, or prophylactic surgery, taking into account their perceived competence, individual autonomy, relatedness to others, and personal preference. The role of intent is limited when considering behavioural change.

CONCLUSIONS

Implementing risk-based breast cancer screening and prevention will require a multifactorial approach. The transition from theory to practice can be supported by developing evidence-based shared decision aids and family-oriented (genetic) counselling programmes.

'No Pink Ribbons': How Women's Lived Experiences With Breast Atypia Inform Decisions Involving Risk-Reducing Medications

Purpose

Atypical hyperplasia (AH) is associated with a nearly 4-fold elevation of lifetime risk for breast cancer, and lobular carcinoma in situ (LCIS) is associated with a 7- to 8-fold risk. Women with AH/LCIS make numerous decisions in the course of treatment, including whether to take a risk-reducing medication, an option relatively few women pursue. We explored women's decision-making processes through patient narratives in an effort to inform decision supports for AH/LCIS.

Methods

We conducted in-depth interviews with 20 English-speaking women with AH/LCIS and no subsequent diagnosis of invasive breast cancer who had enrolled in the Rays of Hope Center for Breast Cancer Research patient registry between April 5, 2012, and March 31, 2016. Interviews were audiotaped, professionally transcribed, and qualitatively analyzed using thematic qualitative content analysis.

Results

We identified three major narrative themes: 1) experiences with medical care; 2) decision-making; and 3) making sense of AH/LCIS. Each major theme had several subthemes, many of which map onto existing decisional theories and heuristics. Subthemes included the impact of life context on diagnosis meaning, emotional responses, changes in self-concept and body image, and understanding of the risk-benefit of risk-reducing medications.

Conclusions

This narrative analysis offers important insights into how lived experience may influence decision-making for women with AH/LCIS. Decision supports that focus not only on analytic decisional processes, but also patients' subjectivities and decisional heuristics, could prove useful for women and their health care providers.

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.

Worry and risk perception of breast cancer in a prevention trial of low dose tamoxifen in midlife postmenopausal hormone users

OBJECTIVE

There is increasing interest in combining postmenopausal hormone therapy (HT) and SERMs in midlife women. We previously showed that refusal to participate in a prevention trial of low dose tamoxifen in HT users was associated with higher worry about breast cancer. Given this counterintuitive finding, we studied which factors influenced worry and risk perception of breast cancer.

METHODS

We assessed the relationships of breast cancer worry and risk perception with age, age at menopause, Gail risk, education, adherence to mammographic screening, BMI, smoking, physical activity, alcohol use, anxiety and depression in 457 midlife HT users who were eligible to participate in the trial.

RESULTS

Women with menopause <48 years were more worried about breast cancer than women with menopause >52 years (OR = 5.0, 95% CI, 1.2-21.1). Worry was also associated with high absolute risk perception and former smoking. Factors associated with higher risk perception were age>60 years, at-risk life style, worry about breast cancer and depression.

CONCLUSIONS

The inverse association between early menopause and worry about breast cancer is in contrast with the known protective effect of early menopause on breast cancer risk and seems to reflect a feeling of aging and disease vulnerability. Our findings indicate that worry about cancer has an affective construct which is independent of breast cancer biology but is engaged in health decision making. Increasing breast cancer risk awareness in subjects high in worry without a plan of emotional coping may therefore be counterproductive because of avoidant attitudes.

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.

Uptake of exemestane chemoprevention in postmenopausal women at increased risk for breast cancer

Despite their efficacy, uptake of selective estrogen receptor modulators for breast cancer chemoprevention remains low. Exemestane, an aromatase inhibitor, has recently been identified as a potential chemopreventive option with fewer serious side effects compared with selective estrogen receptor modulators in postmenopausal women. The purpose of this study was to assess the uptake of exemestane in a breast cancer prevention clinic. A retrospective chart review was conducted to capture chemoprevention uptake by postmenopausal women presenting to the Yale Breast Cancer Prevention Clinic between November 2011 and November 2012. Descriptive statistics of the study population have been presented. Statistical analyses were carried out using SAS 9.3 (SAS Institute Inc., Cary, North Carolina, USA) between December 2012 and February 2013. Of 90 postmenopausal women, 56 were eligible for chemoprevention. Their mean age was 56.8 years. Among the women, 39% had osteopenia or osteoporosis. Thirteen women chose to start chemoprevention medication (23%). Although 31% of the chemopreventive medication administered included exemestane, only four of 56 postmenopausal women opted for exemestane (7%). Chemoprevention uptake rates of postmenopausal women in the setting of a breast cancer prevention clinic are higher than that reported in the general population; however, they remain low overall despite the inclusion of exemestane as an option. A significant proportion of postmenopausal women have decreased bone density, which is a potential barrier to exemestane uptake. The results provide practical implications suggesting that exemestane may have limited impact on breast cancer chemoprevention uptake. Further investigations should focus on understanding the factors that influence, predict, and increase chemoprevention uptake.

Clinician-Reported Barriers to Implementing Breast Cancer Chemoprevention in the UK: A Qualitative Investigation

AIMS

The use of tamoxifen and raloxifene as preventive therapy for women at increased risk of breast cancer was approved by the National Institute for Health and Care Excellence (NICE) in 2013. We undertook a qualitative investigation to investigate the factors affecting the implementation of preventive therapy within the UK.

METHODS

We recruited general practitioners (GPs) (n = 10) and clinicians working in family history or clinical genetics settings (FHCG clinicians) (n = 15) to participate in semi-structured interviews. Data were coded thematically within the Consolidated Framework for Implementation Research.

RESULTS

FHCG clinicians focussed on the perceived lack of benefit of preventive therapy and difficulties interpreting the NICE guidelines. FHCG clinicians felt poorly informed about preventive therapy, and this discouraged patient discussions on the topic. GPs were unfamiliar with the concept of preventive therapy, and were not aware that they may be asked to prescribe it for high-risk women. GPs were reluctant to initiate therapy because it is not licensed, but were willing to continue a prescription if it had been started in secondary or tertiary care.

CONCLUSIONS

Barriers to implementing preventive therapy within routine clinical practice are common and could be addressed by engaging all stakeholders during the development of policy documents.

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.

Barriers to preventive therapy for breast and other major cancers and strategies to improve uptake

The global cancer burden continues to rise and the war on cancer can only be won if improvements in treatment go hand in hand with therapeutic cancer prevention. Despite the availability of several efficacious agents, utilisation of preventive therapy has been poor due to various barriers, such as the lack of physician and patient awareness, fear of side effects, and licensing and indemnity issues. In this review, we discuss these barriers in detail and propose strategies to overcome them. These strategies include improving physician awareness and countering prejudices by highlighting the important differences between preventive therapy and cancer treatment. The importance of the agent-biomarker-cohort (ABC) paradigm to improve effectiveness of preventive therapy cannot be overemphasised. Future research to improve therapeutic cancer prevention needs to include improvements in the prediction of benefits and harms, and improvements in the safety profile of existing agents by experimentation with dose. We also highlight the role of drug repurposing for providing new agents as well as to address the current imbalance between therapeutic and preventive research. In order to move the field of therapeutic cancer prevention forwards, engagement with policymakers to correct research imbalance as well as to remove practical obstacles to implementation is also urgently needed.

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.

Prevention of head and neck squamous cell carcinoma: removing the "chemo" from "chemoprevention"

The concept of chemoprevention whereby the use of a systemic agent is intended to halt the carcinogenesis process has been an attractive topic in head and neck squamous cell carcinoma (HNSCC). Yet, despite the significant efforts over the past decades and the substantial gain in knowledge of the biology of pre-malignant lesions of the head and neck, no tangible indications for chemoprevention have emerged for this disease. The negative results observed in the earlier larger studies using retinoids did not encourage further trials with these agents. Attention has been more recently focused on epidermal growth factor receptor tyrosine kinase inhibitors (EGFR TKIs) as well as cyclo-oxygenase 2 (COX-2) inhibitors with early studies showing encouraging responses but rather poor tolerance to therapy. Natural compounds have gained more interest recently given preclinical evidence of activity as well as a low side effect profile. We herein offer a comprehensive overview of the field of chemoprevention in HNSCC with an in depth analysis of the challenges we face and discuss a road map for future directions.

Acceptability of chemoprevention trials in high-risk subjects

The development and current widespread acceptance of clinical trials is one of the major conceptual advances in research medicine introduced during the second half of the 20th century. Despite general agreement on the scientific merits of randomization, many patients and physicians are however reluctant to participate in randomized, controlled trials. If we focus on chemoprevention in healthy subjects, it is even more essential to evaluate the ethics, logistics, patient's and doctor's acceptability, acute and late toxic effect, patient accrual and compliance of treatment. Furthermore, the decision-making process about participating in a cancer chemoprevention trial is often poorly understood. Adherence to a cancer prevention trial requires in fact a strong sense of awareness and an ability to carefully assess risks and benefits. We review the main aspects in the chemo-preventive approach to patients at high risk for breast and ovarian cancer, focusing on different pharmacological risk reduction strategies, ongoing phase III chemoprevention studies in carriers of BRCA1/2 germline mutation, the psychological and clinical factors implicated in decision making about a trial, and the possible impact of the trial design on the overall acceptability and adherence.

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 Trial Feasibility Using Botanicals in Exceptionally High Risk Populations for Lung Cancer

While chemoprevention with botanicals shows promise in reducing cancer risk, recruitment and retention of participants for trials continues to be costly and presents unique challenges. Knowledge of interest, willingness of target populations and evaluation of design challenges are critical to improve accrual in these chemoprevention trials.

OBJECTIVE

The study assessed interest and willingness of former smokers to participate in a chemoprevention trial using a botanical agent.

METHODS

An introductory letter and survey instrument were mailed to 609 consecutive, former heavy smokers, with no cancer, from a database of 826 subjects at the Moffitt Cancer Center.

RESULTS

202 (40.4%) subjects returned completed surveys. 92-96% reported interest in receiving free lung exams and knowing their lung cancer risk. 88% were interested in participating in a trial evaluating a botanical agent for lung cancer prevention. Over 92% of subjects reported willingness to comply with study requirements; multiple blood draws and trips to the Center, spiral CTs and chest x-rays. Subjects were relatively less enthusiastic (73-79%) about bronchoscopy, taking multiple study agents and assignment to placebo arm.

CONCLUSIONS

Our study strongly suggests feasibility, highlights potential challenges and the significant interest and willingness of this exceptionally high risk population to participate in chemoprevention trials.

Insecurities of women regarding breast cancer research: a qualitative study

Objectives

Only 1.2%–11% of all potential study participants participate in cancer studies. Low participation rates can result in bias or in a failure to obtain data saturation. Subject-scientific psychology assumes that reasons for acting are based on individual premises. The objective of this study was to render reproducible individual reasons of female breast cancer patients to participate or not participate in breast cancer studies using a qualitative approach.

Methods

Problem-based interviews were conducted with female breast cancer patients. The selection of interview partners continued until theoretical data saturation was achieved.

Results

As main arguments against participation emotional overload and too many medication side-effects were stated. Improvement of health-related values, long-term protection and comprehensive follow-up exams were stated as arguments for participation. Trust in the attending physician was mentioned as influencing both participation and non-participation.

Conclusions

A significant influential factor determining willingness to participate in studies was one's contentment with patient-physician communication. In order to guarantee an adequate patient decision-making process, keeping existing standards for patient briefings is absolutely mandatory.

Exemestane for breast cancer prevention: a critical shift?

The Mammary Prevention 3 (MAP.3) placebo-controlled randomized trial in 4,560 high-risk postmenopausal women showed a 65% reduction in invasive breast cancer with the use of exemestane at 35 months median follow-up. Few differences in adverse events were observed between the arms, suggesting a promising risk:benefit balance with exemestane for use in chemoprevention. Yet, the MAP.3 design and implementation raise concerns regarding limited data maturity and not prospectively including key bone-related and other toxicities as study end points. Exemestane for prevention is juxtaposed against selective estrogen receptor modulators and the other aromatase inhibitors. Additional issues for prevention, including the influence of obesity, alternative dosing, and biomarker use in phase III trials, are addressed.

SIGNIFICANCE

The recently completed MAP.3 trial of exemestane for breast cancer prevention offers a potential new standard for pharmaceutical risk reduction in high-risk postmenopausal women. In addition to describing key findings from the publication of MAP.3 and related trials, our review undertakes a detailed analysis of the strengths and weaknesses of MAP.3 as well as the implications for future prevention research.

Acceptability and adherence in a chemoprevention trial among women at increased risk for breast cancer attending the Modena Familial Breast and Ovarian Cancer Center (Italy)

Chemoprevention for women at risk for breast cancer has been shown to be effective, but in actual practice, women's uptake of chemoprevention has been poor. We explored factors that influence acceptability, adherence, and dropout in the International Breast (Prevention) Intervention Study during our first 3 years of activity at the Modena Familial Breast and Ovarian Cancer Center. We evaluated socio-demographic characteristics, health status, adherence, and side effect intensity. Semi-structured interviews analyzed reasons for accepting/refusing/stopping the trial. A total of 471 postmenopausal women were invited to participate, of which 319 declined to participate (68%), 137 accepted to participate (29%), and 15 participants did not make a final decision (3%). Breast cancer-related worries and trust in our preventive and surveillance programs were the most frequent reasons for accepting. Side effect-related worry was the most frequent reason for refusing. General practitioners' and family members' opinions played an important role in the decision-making process. Adherence significantly decreased after a 12-month follow-up, but it remained unchanged after 24- and 36-month follow-ups. Mild/moderate side effects reported by women did not change after 12 months of treatment. Forty percent of women withdrew from the study due to complaints of side effects. We concluded that chemoprevention trials are difficult medical experiments and that the process of deciding about whether or not to participate is based mainly on beliefs and values. This study has important clinical implications. During counselling with prospective participants, it is important to emphasize the potential benefits and to promote an informed choice. How participants make decisions, their belief systems, and their perception of risk are all factors that should be investigated in future research.

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.

Reasons for and against participation in studies of medicinal therapies for women with breast cancer: a debate

BACKGROUND

A special challenge for research studies of breast cancer among females is low patient participation rates. We compiled this systematic review to identify reasons why women with, or at high risk of, breast cancer do or do not participate in medicinal studies of breast cancer.

METHOD

A systematic literature search in the databases Cochrane Library, EMBASE, Medline, Pascal Biomed, ACP Journal Club and CINAHL, as well as searches through reference lists of relevant texts, was performed.

RESULTS

Of 39 relevant full texts, ultimately, nine studies (1 qualitative, 8 quantitative) were included after applying the inclusion criteria. Despite a lack of data material, it was possible to identify various factors influencing women's willingness to participate in medicinal studies and group them into three categories: person-related, study-related, and physician-related.

CONCLUSION

Reasons for or against participation in studies of medicinal therapies by women with, or at high risk of, breast cancer are multi-dimensional, and should be considered when planning such studies to garner higher participation rates. For a more comprehensive picture of factors that affect participation, further studies in this field are recommended.

Cigarette smoking, obesity, physical activity, and alcohol use as predictors of chemoprevention adherence in the National Surgical Adjuvant Breast and Bowel Project P-1 Breast Cancer Prevention Trial

The double-blind, prospective, National Surgical Adjuvant Breast and Bowel Project (NSABP) Breast Cancer Prevention Trial (BCPT) showed a 50% reduction in the risk of breast cancer for tamoxifen versus placebo, yet many women at risk of breast cancer do not adhere to the 5-year course. This first report of the rich BCPT drug adherence data examines predictors of adherence. Between June, 1992 and September, 1997 13,338 women at high risk of breast cancer were randomly assigned to 20 mg/d tamoxifen versus placebo; we analyzed the 11,064 enrolled more than 3 years before trial unblinding. Primary endpoint was full drug adherence (100% of assigned pills per staff report, excluding protocol-required discontinuation) at 1 and 36 months; secondary was adequate adherence (76%-100%). Protocol-specified multivariable logistic regression tested lifestyle factors, controlling for demographic and medical predictors. About 13% were current smokers; 60% were overweight/obese; 46% had moderate/heavy physical activity; 21%, 66%, 13% drank 0, 0-1, 1+ drinks per day, respectively; 91% were adequately adherent at 1 month; and 79% were at 3 years. Alcohol use was associated with reduced full adherence at 1 month (P = 0.016; OR = 0.79 1+ vs. 0), as was college education (P <0.001; OR = 0.78 vs. high school); age (P < 0.001; OR = 1.4 age 60+) and per capita household annual income (P < 0.001; OR = 1.2 per $30,000) with increased adherence. Current smoking (P = 0.003; OR = 0.75), age (P = 0.024, OR = 1.1), college education (P = 0.037; OR = 1.4), tamoxifen assignment (P = 0.031; OR = 0.84), and breast cancer risk (P <.001; OR = 1.5 high vs. low) predicted adequate adherence at 36 months. There were no significant associations with obesity or physical activity. Alcohol use and smoking might indicate a need for greater adherence support.

Acceptability of cancer chemoprevention trials: impact of the design

BACKGROUND

Chemoprevention could significantly reduce cancer burden. Assessment of efficacy and risk/benefit balance is at best achieved through randomized clinical trials.

METHODS

At a periodic health examination center 1463 adults were asked to complete a questionnaire about their willingness to be involved in different kinds of preventive clinical trials.

RESULTS

Among the 851 respondents (58.2%), 228 (26.8%) agreed to participate in a hypothetical chemoprevention trial aimed at reducing the incidence of lung cancer and 116 (29.3%) of 396 women agreed to a breast cancer chemoprevention trial. Randomization would not restrain participation (acceptability rate: 87.7% for lung cancer and 93.0% for breast cancer). In these volunteers, short-term trials (1 year) reached a high level of acceptability: 71.5% and 73.7% for lung and breast cancer prevention respectively. In contrast long-term trials (5 years or more) were far less acceptable: 9.2% for lung cancer (OR=7.7 CI(95%) 4.4-14.0) and 10.5 % for breast cancer (OR=6.9 CI(95%) 3.2-15.8). For lung cancer prevention, the route of administration impacts on acceptability with higher rate 53.1% for a pill vs. 7.9% for a spray (OR=6.7 CI(95%) 3.6-12.9).

CONCLUSION

Overall healthy individuals are not keen to be involved in chemo-preventive trials, the design of which could however increase the acceptability rate.