Early discontinuation of tamoxifen intake in younger women with breast cancer: Is it time to rethink the way it is prescribed?

Social Characteristics and Adherence to Adjuvant Endocrine Therapy in Premenopausal Women With Breast Cancer

PURPOSE

Social characteristics, including cohabitation/marital status and socioeconomic position (SEP)-education level, employment status, and income-influence breast cancer prognosis. We investigated the impact of these social characteristics on adherence to adjuvant endocrine therapy (AET) from treatment initiation to 5 years after diagnosis.

METHODS

We assembled a nationwide, population-based cohort of premenopausal women diagnosed in Denmark with stage I-III, estrogen receptor-positive breast cancer during 2002-2011. We ascertained prediagnostic social characteristics from national registries. AET adherence was based on information from the Danish Breast Cancer Group and operationalized as (1) adherence trajectories (from group-based trajectory modeling) and (2) early discontinuation. We computed odds ratios (ORs) and associated 95% CI to estimate the association of cohabitation and SEP with AET adherence using multinomial and logistic regression models adjusted according to directed acyclic graphs.

RESULTS

Among 4,353 patients, we identified three adherence trajectories-high adherence (57%), slow decline (36%), and rapid decline (6.9%). Compared with cohabiting women, those living alone had higher ORs of slow (1.26 [95% CI, 1.08 to 1.46]) or rapid decline (1.66 [95% CI, 1.27 to 2.18]) versus high adherence. The corresponding ORs for women not working versus employed women were 1.22 (95% CI, 1.02 to 1.45) and 1.76 (95% CI, 1.30 to 2.38). For early discontinuation (17%), the ORs were 1.48 (95% CI, 1.23 to 1.78) for living alone and 1.44 (95% CI, 1.17 to 1.78) for women not working.

CONCLUSION

Adherence to AET was lower among women living alone or unemployed than cohabiting or employed women, respectively. These women may benefit from support programs to enhance AET adherence.

Dataset for a randomised factorial experiment to optimise an information leaflet for women with breast cancer

Background

Adherence to adjuvant endocrine therapy (AET) is low in women with breast cancer, which increases the risk of recurrence and mortality. A consistently reported barrier to adherence is low perceived necessity of AET and high concerns. Existing interventions to support medication beliefs have mixed effectiveness and rarely target medication beliefs specifically. We developed an information leaflet with five candidate components aiming to increase necessity beliefs about AET and reduce concerns; (1) diagrams explaining how AET works; (2) icon arrays displaying the benefits of AET; (3) information about the prevalence of side-effects; (4) answers to common concerns and (5) quotes and pictures from breast cancer survivors. Guided by the multiphase optimisation strategy (MOST), we aimed to optimise the content of the information leaflet. We planned for the dataset to be open access to provide an exemplar for other investigators to use.

Methods

The content of the leaflet was optimised in a fully powered online 2 5 factorial experiment. Each candidate component of the leaflet was operationalised as a factor with two levels; on vs off or enhanced vs basic. Healthy women (n=1604) completed the beliefs about medicines questionnaire and were randomised to view one of 32 versions of the information leaflet. The 32 versions comprised unique combinations of the factor levels corresponding to the five candidate intervention components. Time spent on the information leaflet page of the survey was recorded. After viewing the information leaflet, participants completed the beliefs about medicines questionnaire again, a true/false questionnaire assessing their objective knowledge of AET, a subjective rating of their knowledge of AET, and a questionnaire evaluating their satisfaction with the information they received.

Importance of this dataset

The factorial dataset provides the opportunity for other investigators interested in using the MOST framework to learn about complex factorial designs, using a real dataset.

Insights adjusting for non-adherence in randomized clinical trials: a reanalysis of an adjuvant trial of tamoxifen duration in early breast cancer

BACKGROUND

Several randomized clinical trials provide evidence of the survival benefit of extended adjuvant tamoxifen in women with estrogen receptor (ER)-positive early breast cancer (BC). However, non-adherence may lead to underestimate treatment effects using intention to treat (ITT) methods. We reanalyzed a randomized trial using contemporary statistical methods adjusting for non-adherence.

METHODS

The TAM01 study was a phase 3 trial including women with early BC, who had completed 2-3 years of adjuvant tamoxifen between 1986 and 1995. Participants were randomly assigned to continue tamoxifen up to 10 years or to discontinue the treatment at randomization. Invasive disease-free survival (iDFS) and overall survival (OS) were estimated using marginal structural models (MSM) and rank preserving structural failure time model (RPSFTM).

RESULTS

Of 3830 patients enrolled, 2485 were randomized to extended tamoxifen, and 1345 to treatment discontinuation. The 10-year non-adherence rate in the extended group was 27.2%. Among women with ER-positive BC (n = 2402), extended tamoxifen was associated with a 45% and 21% relative improvement in iDFS by MSM and RPSFTM, respectively (Hazard Ratio (HR), 0.55; 95% Confidence Interval (CI), 0.48-0.64 and HR, 0.79; 95%CI, 0.67-0.95, respectively), a considerable greater benefit than in the ITT analysis (HR, 0.90; 95%CI, 0.81-0.99). The OS reanalysis revealed a substantial benefit of extended tamoxifen (MSM: HR, 0.70; 95%CI, 0.59-0.83; RPSFTM: HR, 0.85; 95%CI, 0.67-1.04), compared to the ITT analyses (HR, 0.94; 95%CI, 0.84-1.07).

CONCLUSION

This analysis emphasizes both the importance of adherence to hormonotherapy in hormone-receptor positive early BC and the usefulness of more complex statistical analyses.

Investigation of Factors Affecting Adherence to Adjuvant Hormone Therapy in Early-Stage Breast Cancer Patients: A Comprehensive Systematic Review

PURPOSE

Adherence and persistence to adjuvant hormone therapy (AHT) are seldom maintained among early-stage hormone receptor-positive breast cancer (BC) survivors, despite the significant clinical benefits of long-term AHT. As the factors influencing adherence to AHT remain unclear, this study aimed to comprehensively identify such factors and classify them into specific dimensions.

METHODS

PubMed, Cochrane Library, Embase, PsycINFO, and CINAHL were searched for qualified articles. The search mainly focused on three components: early-stage (0-III) BC, oral AHT administration, and adherence to AHT, with keywords derived from MeSH and entry terms. The factors identified were then classified into six categories based on a modified WHO multidimensional model.

RESULTS

Overall, 146 studies were included; the median sample size was 651 (range, 31-40,009), and the mean age of the population was 61.5 years (standard deviation, 8.3 years). Patient- and therapy-related factors were the most frequently investigated factors. Necessity/concern beliefs and self-efficacy among patient-related factors were consistently related to better adherence than depression. Although drug side effects and medication use cannot be modified easily, a refined prescription strategy for the initiation and switching of AHT is likely to increase adherence levels.

CONCLUSION

An effective psychological program that encourages positive views and beliefs about medication and management strategies for each therapy may be necessary to improve adherence to AHT. Social support and a sense of belonging can be enhanced through community participation and social media for better adherence to AHT. Patient-centered communication and appropriate recommendations by physicians may be attributable to better adherence outcomes. Findings from systematically organized factors that influence adherence to AHT may contribute to the establishment of intervention strategies to benefit patients with early-stage BC to achieve optimal health.

Breast cancer therapy in women under 35 years and between 50 and 69 years: influence of the observation period

PURPOSE

In recent years, therapeutic strategies based on tumour biology have increased significantly. We aimed to provide an overview of the recent changes in patient characteristics, treatment procedures and survival factors for two groups of patients: women younger than 35 years and women between 50 and 69 years.

METHODS

We used data from the population-based Cancer Registry Magdeburg. Subjects included women with non-metastatic breast cancer treated between 2000 and 2015. We compared between two observation periods: 2000-2007 and 2008-2015.

RESULTS

There was an increase in patient survival from the first to the second observation period. Tumour characteristics and treatment modalities changed, especially in the group of older patients. The proportion of prognostically more favourable tumour subtypes, such as Luminal A, increased significantly. Between 2008 and 2015, there were more hormone receptor-positive, lymph-node-negative, human epidermal growth factor receptor-2 (HER2)-negative and well-differentiated tumours. Surgical methods were associated with significantly reduced radicality, while the rate of neoadjuvant therapy increased in both groups. There was a decrease in cyclophosphamide, methotrexate and 5-fluoruracil (CMF) and anthracycline therapies, but taxane-containing chemotherapy increased. While tamoxifen was used more frequently in younger patients in the later observation period, its use was reduced in older patients, superseded by aromatase inhibitors. Furthermore, the use of immune therapy increased.

CONCLUSION

In both age groups, but primarily in older patients, there were significant changes in tumour biology and treatment options between the two observation periods. These changes have led to a continuous improvement in patient outcomes.

Estimating medication adherence from Electronic Health Records: comparing methods for mining and processing asthma treatment prescriptions

BACKGROUND

Medication adherence is usually defined as the extent of the agreement between the medication regimen agreed to by patients with their healthcare provider and the real-world implementation. Proactive identification of those with poor adherence may be useful to identify those with poor disease control and offers the opportunity for ameliorative action. Adherence can be estimated from Electronic Health Records (EHRs) by comparing medication dispensing records to the prescribed regimen. Several methods have been developed in the literature to infer adherence from EHRs, however there is no clear consensus on what should be considered the gold standard in each use case. Our objectives were to critically evaluate different measures of medication adherence in a large longitudinal Scottish EHR dataset. We used asthma, a chronic condition with high prevalence and high rates of non-adherence, as a case study.

METHODS

Over 1.6 million asthma controllers were prescribed for our cohort of 91,334 individuals, between January 2009 and March 2017. Eight adherence measures were calculated, and different approaches to estimating the amount of medication supply available at any time were compared.

RESULTS

Estimates from different measures of adherence varied substantially. Three of the main drivers of the differences between adherence measures were the expected duration (if taken as in accordance with the dose directions), whether there was overlapping supply between prescriptions, and whether treatment had been discontinued. However, there are also wider, study-related, factors which are crucial to consider when comparing the adherence measures.

CONCLUSIONS

We evaluated the limitations of various medication adherence measures, and highlight key considerations about the underlying data, condition, and population to guide researchers choose appropriate adherence measures. This guidance will enable researchers to make more informed decisions about the methodology they employ, ensuring that adherence is captured in the most meaningful way for their particular application needs.

Compliance to adjuvant endocrine therapy and survival in breast cancer patients

BACKGROUND

Data on compliance to adjuvant endocrine treatment (ET) is mainly reported from prospective clinical trials or from smaller retrospective cohorts without correlation to outcome.

AIMS

To determine compliance to adjuvant ET and the impact on survival in a population-based series of patients with early breast cancer (BC) advised ET.

PATIENTS AND METHODS

1090 consecutive patients with hormone receptor positive (HR+) stage I-III BC diagnosed from 1 January 1997 to 31 December 2003 from one health care region of Sweden were included. Data on tumour, type of ET, compliance, reason for termination and outcome were collected. Statistical analyses were calculated with patients in three groups.

RESULTS

72 patients were excluded leaving 1018 patients with a HR+ stage I to III BC for analyses. The most common ET was tamoxifen (n = 751, 73.8%). At the last follow up (31 Dec 2019) with a median follow-up of 18 years (interquartile range 16-22) 228 (22.4%) patients had a relapse. 71.1% of the included patients were compliant to endocrine therapy. Older patients ≥74 years had lower compliance, 61% compared with 75% in the other age groups (≤50 years and 51-73 years) (p < 0001), other parameters including type of ET were not associated with compliance. Low compliance remained as an independent risk factor in multivariate analyses for lower relapse-free survival, HR=1.83, 95% Confidence Interval (CI) 1.52-2.19, p < 0.001 and for time to BC death, HR=2.69, 95%CI 1.82-3.98, p < 0.001.

CONCLUSIONS

Patients compliant to adjuvant ET have an improved survival.

Approaches to Fertility Preservation for Young Women With Breast Cancer

In patients with early breast cancer, the combination of different systemic treatment strategies, including chemotherapy, endocrine therapy, targeted therapy, and more recently also immunotherapy has demonstrated to significantly improve their survival outcomes. However, this gain is often obtained at the cost of higher toxicity calling for the need of increased attention toward survivorship-related issues, including fertility preservation in young women. According to available guidelines, health care providers should offer oncofertility counseling to all patients with cancer diagnosed at reproductive age. Counselling should focus on the risk of gonadotoxicity of anticancer treatments and on the access to fertility preservation techniques. However, several surveys have demonstrated suboptimal implementation of these recommendations. This review aims at summarizing the available evidence on oncofertility to guide health care providers involved in the management of young women with breast cancer. Available and effective options for fertility preservation include oocyte/embryo cryopreservation or ovarian tissue cryopreservation. Patient, disease, and treatment characteristics should be carefully considered when offering these strategies. Ovarian function preservation with gonadotrophin-releasing hormone agonists during chemotherapy should be discussed and offered to every premenopausal woman concerned about developing premature ovarian insufficiency and independently of her wish to preserve fertility. Current available data confirm that pregnancy occurring after proper treatment for breast cancer is safe, both in terms of long-term clinical outcomes and for the babies. Fertility preservation and pregnancy desire should be pivotal components of the multimodal management of breast cancer in young women, and require a multidisciplinary approach based on close collaborations between oncologists and fertility specialists.

Tumor characteristics, therapy, and prognosis in young breast cancer patients ≤ 35 years

PURPOSES

Young breast cancer patients aged 35 years and younger are a small group of women who tend to present at high-risk form of the disease. More analysis of the data on tumor characteristics, treatment, and survival is necessary to help improving treatment and outcome.

METHODS

In this retrospective study, we compared the clinical and tumor characteristics, the treatments, and the survival of 257 women aged ≤ 35 years, with 6566 women aged 50-69 years. We used a registry-based data of patients with invasive, non-metastatic breast cancer diagnosed between 2000 and 2015.

RESULTS

Young women showed lower rate of hormone receptor (HR) positivity. Their tumors were more often HER2-positive, which showed lower rate of differentiation and higher rate of Ki-67 expression compared to their older counterparts. Women aged 35 years and younger were more likely to undergo neoadjuvant therapy and mastectomy. Endocrine therapy was underrepresented in young patients. 5-Year disease-free survival (DFS) was significantly lower in the younger patient group (81.7% vs. 91.3%, p < 0.001), while 5-year overall survival (OS) was not impaired (91.4% vs. 91.1%, p = 0.847).

CONCLUSION

The unfavorable disease-free survival in the group of younger patients might be explained by their unfavorable tumor characteristics. The surgical treatment appears to be more aggressive in young breast cancer patients and is more frequently combined with chemotherapy and immunotherapy, either in a neoadjuvant or in an adjuvant setting.

The impact of HIV on non-adherence for tamoxifen among women with breast cancer in South Africa

PURPOSE

Women living with HIV (WLWH) and breast cancer (BC) have worse overall survival than HIV-negative women with BC, and poor adherence to prescribed tamoxifen is known to contribute to poor survival. We therefore investigated the association of HIV infection with adherence to adjuvant tamoxifen among women with localized hormone receptor (HR)-positive breast cancer in South Africa.

METHODS

Among 4,097 women diagnosed with breast cancer at six hospitals in the prospective South African Breast Cancer and HIV Outcomes (SABCHO) cohort study between July 2015 and December 2020, we focused on black women with stages I-III HR-positive breast cancer who were prescribed 20 mg of adjuvant tamoxifen daily. We collected venous blood once from each participant during a routine clinic visit, and analyzed concentrations of tamoxifen and its metabolites using a triple quadruple mass spectrometer. We defined non-adherence as a tamoxifen level < 60 ng/mL after 3 months of daily tamoxifen use. We compared tamoxifen-related side effects, and concurrent medication use among women with and without HIV and developed multivariable logistic regression models of tamoxifen non-adherence.

RESULTS

Among 369 subjects, 78 (21.1%) were WLWH and 291 (78.9%) were HIV-negative. After a median (interquartile range) time of 13.0 (6.2-25.2) months since tamoxifen initiation, the tamoxifen serum concentration ranged between 1.54 and 943.0 ng/mL and 208 (56.4%) women were non-adherent to tamoxifen. Women < 40 years of age were more likely to be non-adherent than women > 60 years (73.4% vs 52.6%, odds ratio (OR) = 2.49, 95% confidence interval (CI) = 1.26-4.94); likewise, WLWH (70.5% vs 52.6%, OR = 2.16, 95% CI = 1.26-3.70) than HIV-negative women. In an adjusted model WLWH had twice the odds of non-adherence to tamoxifen, compared to HIV-negative women (OR = 2.40, 95% CI = 1.11-5.20).

CONCLUSION

High rates of non-adherence to adjuvant tamoxifen may limit the overall survival of black South African women with HR-positive breast cancer, especially among WLWH.

Extended adjuvant endocrine treatment for premenopausal women: A Delphi approach to guide clinical practice

The use of an aromatase inhibitor (AI) in combination with ovarian function suppression (OFS) has become the mainstay of adjuvant endocrine therapy in high-risk premenopausal patients with hormone receptor-positive breast cancer. Although five years of such therapy effectively reduces recurrence rates, a substantial risk of late recurrence remains in this setting. Multiple trials have shown that extending AI treatment beyond five years could offer further protection. However, as these studies comprised only postmenopausal patients, no direct evidence currently exists to inform about the potential benefits and/or side effects of extended AI + OFS therapies in premenopausal women. Given these grey areas, we conducted a Delphi survey to report on the opinion of experts in breast cancer treatment and summarize a consensus on the discussed topics. A total of 44 items were identified, all centred around two main themes: 1) defining reliable prognostic factors to pinpoint premenopausal patients eligible for endocrine therapy extension; 2) designing how such therapy should optimally be administered in terms of treatment combinations and duration based on patients' menopausal status. Each item was separately discussed and anonymously voted by 12 experts representing oncological institutes spread across Italy. The consensus threshold was reached in 36 out of 44 items (82%). Herein, we discuss the levels of agreement/disagreement achieved by each item in relation to the current body of literature. In the absence of randomized trials to guide the tailoring of extended AI treatment in premenopausal women, conclusions from our study provide a framework to assist routine clinical practice.

The French Early Breast Cancer Cohort (FRESH): A Resource for Breast Cancer Research and Evaluations of Oncology Practices Based on the French National Healthcare System Database (SNDS)

Simple Summary

Because of an important disparity of care pathways and quality of care among women diagnosed with an early-stage breast cancer, we aimed to create a unique cohort of patients including all French women aged 18 years or over, treated by surgery and registered in the general health insurance coverage plan. After aggregating and annotating medico-administrative data on 235,368 early breast cancer patients, we open up perspectives for research on adverse effects, morbidity, mortality, the monitoring of care consumption, or medical-economic studies. We describe data sources, inclusion, and exclusion criteria, basic descriptive analyses, and longitudinal trends over time.

Abstract

Background: Breast cancer (BC) is the most frequent cancer and the leading cause of cancer-related death in women. The French National Cancer Institute has created a national cancer cohort to promote cancer research and improve our understanding of cancer using the National Health Data System (SNDS) and amalgamating all cancer sites. So far, no detailed separate data are available for early BC. Objectives: To describe the creation of the French Early Breast Cancer Cohort (FRESH). Methods: All French women aged 18 years or over, with early-stage BC newly diagnosed between 1 January 2011 and 31 December 2017, treated by surgery, and registered in the general health insurance coverage plan were included in the cohort. Patients with suspected locoregional or distant metastases at diagnosis were excluded. BC treatments (surgery, chemotherapy, targeted therapy, radiotherapy, and endocrine therapy), and diagnostic procedures (biopsy, cytology, and imaging) were extracted from hospital discharge reports, outpatient care notes, or pharmacy drug delivery data. The BC subtype was inferred from the treatments received. Results: We included 235,368 patients with early BC in the cohort (median age: 60 years). The BC subtype distribution was as follows: luminal (80.2%), triple-negative (TNBC, 9.5%); HER2⁺ (10.3%), or unidentifiable (n = 44,388, 18.9% of the cohort). Most patients underwent radiotherapy (n = 200,685, 85.3%) and endocrine therapy (n = 165,655, 70.4%), and 38.3% (n = 90,252) received chemotherapy. Treatments and care pathways are described. Conclusions: The FRESH Cohort is an unprecedented population-based resource facilitating future large-scale real-life studies aiming to improve care pathways and quality of care for BC patients.

Adherence to oral hormonal anticancer agents in breast cancer

There is an increasing trend towards using oral antitumoral agents in oncological patients. Compared to parenteral therapy, oral treatment offers convenience for both the patient and the healthcare system, with similar efficacy. However, the benefit deriving from oral drugs will be obtained only if patients adhere strictly to the treatment. Medical oncologists must therefore seek to optimize patient adherence. Breast cancer patients, particularly, are often treated with oral hormonal anticancer agents. In this review, we summarized evidence about adherence of breast cancer patients to oral hormonal anticancer agents and the consequences of poor compliance, the barriers to oral treatment and strategies to overcome them.

Factors influencing five-year adherence to adjuvant endocrine therapy in breast cancer patients: A systematic review

Purpose

This systematic review aimed to determine the rate and identify correlates of adherence and persistence over five years of treatment with adjuvant endocrine therapy in female breast cancer patients.

Methods

Relevant articles were identified from Medline, Embase, AMED, PsycINFO, International Pharmaceutical Abstracts, and APA PsycArticles. Studies that measured patient adherence in the implementation or persistence phase for a period of at least five years using objective or multiple measures of adherence and investigated correlates of adherence were included. The titles, abstracts and full articles were screened and reviewed by two authors and any discrepancies were discussed with a third author.

Results

Twenty-six studies were included. Mean rate of adherence at five-year for implementation phase was 66.2% (SD = 17.3%), and mean persistence was 66.8% (SD = 14.5%). On average, adherence decreased by 25.5% (SD = 9.3%) from the first to fifth year. Higher rate of adherence was observed through self-report in comparison to database or medical record. Older age, younger age, higher comorbidity index, depression and adverse effects were associated with lower adherence. Treatment with aromatase inhibitors, received chemotherapy, and prior medication use were associated with improved adherence.

Conclusion

Adherence to adjuvant endocrine therapy decreased from the first to fifth year of treatment. On average, one-third of patients were not adherent to treatment by the fifth year. Nineteen recurring factors were found to be significantly associated with long-term adherence in multiple studies. Further research using objective or multiple measures of adherence are needed to improve validity of results.

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On average, adherence fell by 25.5% from the first to the fifth year of treatment.

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Self-reported adherence may overestimate patient adherence.

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Nineteen recurring factors were associated with adherence.

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Having adverse effects was negatively associated with adherence.

Young Women with Breast Cancer in Resource-Limited Settings: What We Know and What We Need to Do Better

Young women with breast cancer (YWBC) account for a variable proportion of patients diagnosed with breast cancer around the globe, with a higher prevalence in resource-limited settings than in high-income countries. This group represents a unique population that warrants special attention due to specific biological considerations and age-specific supportive care issues. This review aims to explore existing knowledge regarding YWBC's needs, particularly in resource-restricted settings. To date, scarce information regarding the care of YWBC in resource-constrained countries is available, with most reports describing suboptimal care in terms of survivorship needs. Health care providers should implement actions to improve endocrine treatment adherence, referrals for fertility counseling and preservation, contraceptive use compliance, timely body image and sexual function interventions, comprehensive genetic risk assessments, and early quality of life and psychosocial health interventions. While high costs act as a barrier for optimal care in resource-limited settings, improving patient education represents a promising and cost-effective solution to improve patient care. Future research on developing tailored educational resources for YWBC in resource-limited settings should be considered a priority.

Adjuvant endocrine therapy for premenopausal women with breast cancer: Patient adherence and physician prescribing practices in Mexico

BACKGROUND

In resource-constrained settings, data regarding breast cancer patients' adherence to endocrine therapy (ET) and physicians' prescribing practices is limited. This study aims to decrease this knowledge gap in a real-world clinical practice.

METHODS

Premenopausal women with stage 0-III hormone-sensitive breast cancer and receiving adjuvant ET during the past 1-5 years were identified in three Mexican referral centers. Participants' self-reported ET compliance, clinicopathologic characteristics, ET-related knowledge and beliefs, experienced adverse effects, social support, and patient-physician relationships were evaluated. Physician ET prescribing practices were compared with the gold standard according to international and national guidelines to assess clinicians' adherence to standard-of-care prescription.

RESULTS

In total, 95/132 (72%) and 35/132 (27%) participants reported complete and acceptable adherence, respectively. Incomplete adherence was mainly attributed to forgetfulness, adverse effects, and unwillingness to take ET. Being employed/studying (p = 0.042), worrying about long-term ET use (p = 0.031), and experiencing >7 ET-related symptoms (p = 0.018) were associated with incomplete adherence. Guideline-endorsed regimens were prescribed in 84/132 (64%) patients, while the rest should have undergone ovarian function suppression (OFS) but instead received tamoxifen monotherapy.

CONCLUSIONS

Premenopausal Mexican women self-report remarkably high rates of adequate ET adherence. However, a considerable proportion misses ≥1 doses/month, usually because of forgetfulness. Notably, only 64% receive standard-of-care ET due to suboptimal prescription of OFS. Interventions that remind patients to take their ET, refine physicians' knowledge on the importance of OFS in high-risk patients, and increase access to OFS could prove pivotal to enhance optimal ET implementation and adherence, which could translate into improved patient outcomes.

Young Women With Breast Cancer: Treatment, Care, and Nursing Implications

BACKGROUND

Young women with breast cancer (YWBC) are more likely to have aggressive disease, carry mutations for hereditary cancer genes, and experience higher mortality. They also may face reduced fertility because of the toxicity of chemotherapy.

OBJECTIVES

This article aims to present a review of YWBC treatments, sequelae of treatment, and psychosocial challenges.

METHODS

The authors performed a review of guideline-supported treatment options, patient resources, and nursing implications.

FINDINGS

Because of high-risk cancers and a lack of specific treatment guidelines, healthcare providers may consider aggressive treatments for younger patients. However, studies indicate that the foundation for treatment decisions for YWBC are best based on disease stage and National Comprehensive Cancer Network guidelines.

Five-Year Adjuvant Endocrine Therapy Adherence Trajectories Among Women With Breast Cancer: A Nationwide French Study Using Administrative Data

BACKGROUND

Adjuvant endocrine therapy (AET) improves long-term survival of breast cancer patients, yet many women are nonadherent or discontinue this treatment. In this study we aimed to describe AET adherence trajectories over 5 years after treatment initiation and to identify factors associated with these trajectories, in a nationwide French cohort of breast cancer survivors.

PATIENTS AND METHODS

Every woman diagnosed with a first nonmetastatic breast cancer in 2011 in France who initiated AET in the 12 months after surgery was included from the French cancer cohort. We identified all reimbursements for AET from national health administrative data sets and modeled AET adherence trajectories over 5 years, using group-based trajectory modeling on the basis of the monthly proportion of days covered by AET. Associated factors were identified using multinomial logistic regressions.

RESULTS

We included 33,260 women. A 6-trajectory model was selected: 1, immediate discontinuation (6.6%); 2, continuous suboptimal adherence (4.3%); 3, progressive nonadherence then discontinuation (6.3%); 4, early nonadherence then discontinuation (5.7%); 5, continuous optimal adherence (68.8%); and 6, late nonadherence then discontinuation (8.3%). The main factors associated with nonadherence trajectories were extreme age (younger than 50 and older than 70 years) and switching AET.

CONCLUSION

Approximately 70% of women had optimal adherence over all 5 years. The original nationwide approach enabled us to identify the "continuous suboptimal adherence trajectory" never previously described.

Assessing Predictors of Tamoxifen Nonadherence in Patients with Early Breast Cancer

Adjuvant endocrine therapy (AET) is generally proposed to all patients with hormone receptor-positive breast cancer to reduce the risk of recurrence and death. Adherence to therapy is crucial. However, non-adherence to AET is common, with estimates of up to 50% of patients not successfully completing a five-year course of treatment, and it is significantly associated with lower survival rates and a higher risk of recurrence. Currently, no gold standard is available to assess adherence. Several studies, most of them retrospective in nature, have used both direct and indirect methods to monitor the adherence to therapy in breast cancer. The indirect method is more widely used, and it is based on pharmacy prescription refills and patient administered questionnaires. On the other hand, direct methods such as a measurement of the level of the drug or its metabolites in blood or urine are much more precise, but more expensive and not routinely implemented. In this review, we analyzed the results of the major studies focused on the adherence to tamoxifen in breast cancer patients. We identified several factors associated with poor adherence, such as the side effects of therapy, the lack of shared decision-making between the physician and patient, the context in which the discussion takes place, and whether the patients are enrolled in a clinical trial. Moreover, we discussed possible methods to improve adherence to adjuvant therapy in breast cancer.

Influence of Traditional Chinese Medicine on Medical Adherence and Outcome in Estrogen Receptor (+) Breast Cancer Patients in Taiwan: A Real-World Population-Based Cohort Study

BACKGROUND

Medical adherence is often higher in clinical trials than in real world practice. The aim of this study was to investigate the effects of traditional Chinese medicine (TCM) on medical adherence to hormonal therapy (HT) and survival outcome in ER (+) breast cancer patients in Taiwan.

SUBJECTS AND METHODS

Using a nationwide longitudinal population-based database, we enrolled patients with newly diagnosed ER-positive breast cancer who had received HT, and followed for up to 5 years (N = 872). Medication adherence in terms of medication possession ratios (MPR) and patient outcome were evaluated with or without TCM exposure. We applied logistic regression and Cox proportional hazards (PH) analysis to identify factors, including TCM exposure, associated with adherence to HT and mortality.

RESULTS

MPR to HT in general decreased over the 5-year period post breast cancer diagnosis. Both TCM and MPR to HT ≥ 80% were significantly associated with reduced risk of breast cancer-associated mortality. Subgroup analysis revealed that TCM annual visits ≥ 3 times with CHP prescription 1~90 days per year affected mortality reduction most significantly (HR: 0.26; 95% CI = 0.08-0.83; p < 0.05) compared to other TCM use. In contrast, using TCM (either short-term or long-term) was not associated with MPR in HT.

CONCLUSIONS

Our results supported the potential advantage of TCM on breast cancer-associated mortality, whereas TCM use does not compromise medical adherence to HT. This study offers important insights in integrative therapy for HT in patients with estrogen receptor (+) breast cancer.

Adherence to Adjuvant Tamoxifen in Mexican Young Women with Breast Cancer

BACKGROUND

Breast cancer (BC) in young women is characterized by an unfavorable prognosis in hormone receptor-positive/HER2-negative tumors, which may be explained by low rates of tamoxifen adherence. In Mexico, up to 14% of all BC diagnoses occur in young women and no data on tamoxifen adherence has been reported.

OBJECTIVE

To estimate the rate of adherence to adjuvant tamoxifen in Mexican young women with BC (YWBC).

METHODS

A cross-sectional survey was conducted at the National Cancer Institute in Mexico City, among YWBC (≤40 years at diagnosis) receiving adjuvant tamoxifen. Adherence was measured subjectively, through self-reported surveys, and objectively, through medication possession ratio (MPR). Descriptive statistics were used to analyze sociodemographic characteristics. To compare associations between patients' characteristics and adherence, Chi-square test was used for categorical variables and Student's t-test or Mann-Whitney U-test for quantitative variables.

RESULTS

A total of 141 YWBC receiving adjuvant tamoxifen were included. Regarding subjective adherence, 95% expressed taking tamoxifen regularly, 70% reported missing 0 doses in the past 30 days, and 71.6% reported having adverse effects. Regarding objective adherence, 74.8% of patients had an MPR ≥80%. The association between subjective and objective adherence was statistically significant (p = 0.004). Subjective adherence was associated with not skipping tamoxifen doses when feeling worse. Objective adherence was associated with having a stable job, not skipping tamoxifen doses when feeling worse, taking additional medications, and time on tamoxifen treatment. Fifty-six percent considered the information on tamoxifen to be insufficient and 37% not understandable.

CONCLUSION

In our study, high subjective and objective adherence rates to adjuvant tamoxifen were reported, although an important proportion of women reported high rates of adverse effects and not fully understanding the benefits of tamoxifen. Strategies to increase tamoxifen adherence may be even more important now that longer durations of treatment or further ovarian function suppression have become the standard of care in YWBC.

Potentially Modifiable Factors Associated with Adherence to Adjuvant Endocrine Therapy among Breast Cancer Survivors: A Systematic Review

Adjuvant endocrine therapy (AET) reduces risk of breast cancer recurrence. However, suboptimal adherence and persistence to AET remain important clinical issues. Understanding factors associated with adherence may help inform efforts to improve use of AET as prescribed. The present systematic review examined potentially modifiable factors associated with adherence to AET in accordance with PRISMA guidelines (PROSPERO registration ID: CRD42019124200). All studies were included, whether factors were significantly associated with adherence or results were null. This review also accounted for the frequency with which a potentially modifiable factor was examined and whether univariate or multivariate models were used. This review also examined whether methodological or sample characteristics were associated with the likelihood of a factor being associated with AET adherence. A total of 68 articles were included. Potentially modifiable factors were grouped into six categories: side effects, attitudes toward AET, psychological factors, healthcare provider-related factors, sociocultural factors, and general/quality of life factors. Side effects were less likely to be associated with adherence in studies with retrospective or cross-sectional than prospective designs. Self-efficacy (psychological factor) and positive decisional balance (attitude toward AET) were the only potentially modifiable factors examined ≥10 times and associated with adherence or persistence ≥75% of the time in both univariate and multivariate models. Self-efficacy and decisional balance (i.e., weight of pros vs. cons) were the potentially modifiable factors most consistently associated with adherence, and hence may be worth focusing on as targets for interventions to improve AET adherence among breast cancer survivors.

Early Discontinuation of Endocrine Therapy and Recurrence of Breast Cancer among Premenopausal Women

PURPOSE

Premenopausal women diagnosed with estrogen receptor (ER)-positive breast cancer are prescribed 5-10 years of endocrine therapy to prevent or delay recurrence. In this study, we evaluated the association between early discontinuation of endocrine therapy and breast cancer recurrence in a cohort of premenopausal women.

EXPERIMENTAL DESIGN

We identified 4,503 patients with premenopausal ER-positive breast cancer who initiated adjuvant endocrine therapy and were registered in the Danish Breast Cancer Group clinical database (2002-2011). Women were excluded if they had a recurrence or were lost to follow-up less than 1.5 years after breast cancer surgery. Endocrine therapy was considered complete if the patient received at least 4.5 years of treatment or discontinued medication less than 6 months before recurrence. Exposure status was updated annually and modeled as a time-dependent variable. We accounted for baseline and time-varying confounders via time-varying weights, which we calculated from multivariable logistic regression models, and included in regression models to estimate HRs and 95% confidence intervals (CIs) associating early discontinuation with recurrence.

RESULTS

Over the study follow-up, 1,001 (22%) women discontinued endocrine therapy. We observed 202 (20%) recurrences among those who discontinued endocrine therapy, and 388 (11%) among those who completed the recommended treatment. The multivariable-adjusted estimated rate of recurrence was higher in women who discontinued endocrine therapy relative to those who completed their treatment (hazard ratio, 1.67; 95% CI, 1.25-2.14).

CONCLUSIONS

These results highlight the importance of clinical follow-up and behavioral interventions that support persistence of adjuvant endocrine therapy to prevent breast cancer recurrence.

The Prognostic Impact of Age at Diagnosis Upon Breast Cancer of Different Immunohistochemical Subtypes: A Surveillance, Epidemiology, and End Results (SEER) Population-Based Analysis

Background and Objectives: The influence of age at diagnosis of breast cancer upon the prognosis of patients with different immunohistochemical (IHC)-defined subtypes is still incompletely defined. Our study aimed at examining the association of age at diagnosis and risk of breast cancer-specific mortality (BCSM). Methods: 172,179 eligible breast cancer patients were obtained for our study cohort using the Surveillance, Epidemiology, and End Results database from 2010 to 2015. Patients were classified into four IHC-defined subtypes according to their ER, PgR, and HER2 status. Kaplan-Meier plots were used to describe BCSM among patients in different age groups. A Cox proportional hazards model was used for multivariate analysis. A multivariable fractional polynomial model within the Cox proportional hazards model was used to evaluate the relationship between age at diagnosis and the risk of BCSM. Results: For the whole cohort, the median follow-up time was 43 months. Patients younger than 40 years and those older than 79 years presented with the worst BCSM (hazard ratio [HR] 1.13, 95% confidence interval [CI] 1.03-1.23, and HR 3.52, 95% CI 3.23-3.83, respectively, p < 0.01, with age 40-49 years as the reference). The log hazard ratios of hormone receptor (HoR)(+)/HER2(-) patients formed a quadratic relationship between age at diagnosis and BCSM, but not in the other three subtypes of breast cancer. In the HoR(+)/HER2(-) subtype, patients younger than 40 years had worse BCSM than those aged at 40-49 years (HR 1.26, 95% CI 1.10-1.45, and p < 0.01). Conclusions: Women diagnosed with HoR(+)/HER2(-) breast cancer younger than 40 years or older than 79 years of age suffer higher rates of cancer-specific mortality. Young age at diagnosis may be particularly prognostic in HoR(+)/HER2(-) breast cancer.

Improving Adherence to Adjuvant Hormonal Therapy Among Disadvantaged Women Diagnosed with Breast Cancer in South Carolina: Proposal for a Multimethod Study

BACKGROUND

Current clinical guidelines recommend that hormone receptor-positive breast cancer survivors take adjuvant hormonal therapy (AHT) for 5 to 10 years, following the end of definitive treatment. However, fewer than half of patients adhere to the guidelines, and suboptimal adherence to AHT is associated with an increased risk of breast cancer mortality. Research has extensively documented sociodemographic and disease-specific factors associated with adherence to AHT, but very little evidence exists on behavioral factors (eg, knowledge, patient-provider communication) that can be modified and targeted by interventions.

OBJECTIVE

The goal of this study is to develop and test a theory-based, multilevel intervention to improve adherence to AHT among breast cancer survivors from racially and socioeconomically disadvantaged backgrounds (eg, Medicaid-insured). The specific aims are to (1) explore multilevel (eg, patient, health care system) factors that influence adherence to AHT; (2) develop a theory-based, multilevel intervention to improve adherence to AHT; and (3) pilot test and evaluate the intervention developed in Aim 2.

METHODS

For Aim 1, we will recruit breast cancer survivors and health care professionals to participate in semistructured interviews to gain their perspectives about barriers and facilitators to AHT use. We will conduct a directed content analysis of the Aim 1 qualitative interview data. For Aim 2, we will integrate Aim 1 findings and current literature into the design of a multilevel intervention using an Intervention Mapping approach. For Aim 3, we will recruit Medicaid-insured breast cancer survivors to assess the feasibility of the pilot intervention.

RESULTS

From May 2016 to July 2018, we completed interviews with 19 breast cancer survivors and 23 health care professionals in South Carolina. We will conduct a directed content analysis of the qualitative interview data. Results from this analysis will be used, in combination with current literature, to design (Aim 2) and pilot test a theory-based multilevel intervention (Aim 3) in Summer 2021. Results of the pilot are expected for Fall 2021.

CONCLUSIONS

This study will provide a deeper understanding of how to improve adherence to AHT, using a novel and multilevel approach, among socioeconomically disadvantaged breast cancer survivors who often experience disproportionate breast cancer mortality.

INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID)

DERR1-10.2196/17742.

Measuring and reporting treatment adherence: What can we learn by comparing two respiratory conditions?

Medication non-adherence, defined as any deviation from the regimen recommended by their healthcare provider, can increase morbidity, mortality and side effects, while reducing effectiveness. Through studying two respiratory conditions, asthma and tuberculosis (TB), we thoroughly review the current understanding of the measurement and reporting of medication adherence. In this paper, we identify major methodological issues in the standard ways that adherence has been conceptualised, defined and studied in asthma and TB. Between and within the two diseases there are substantial variations in adherence reporting, linked to differences in dosing intervals and treatment duration. Critically, the communicable nature of TB has resulted in dose-by-dose monitoring becoming a recommended treatment standard. Through the lens of these similarities and contrasts, we highlight contemporary shortcomings in the generalised conceptualisation of medication adherence. Furthermore, we outline elements in which knowledge could be directly transferred from one condition to the other, such as the application of large-scale cost-effective monitoring methods in TB to resource-poor settings in asthma. To develop a more robust evidence-based approach, we recommend the use of standard taxonomies detailed in the ABC taxonomy when measuring and discussing adherence. Regimen and intervention development and use should be based on sufficient evidence of the commonality and type of adherence behaviours displayed by patients with the relevant condition. A systematic approach to the measurement and reporting of adherence could improve the value and generalisability of research across all health conditions.

Current State of the Art in the Adjuvant Systemic Treatment of Premenopausal Patients With Early Breast Cancer

Breast cancer is the most frequent malignancy diagnosed in premenopausal women. In this age group, breast tumors tend to be diagnosed at more advanced stages and to harbor more aggressive biological features. In addition, specific age-related issues including genetic counseling, fertility preservation, impact on social and couple relationships, working life, and management of long-term side effects should be considered highly relevant when managing early breast cancer in premenopausal women. Therefore, the care of these patients is particularly complex and a multidisciplinary approach is mandatory. The present review summarizes the current state of art in the adjuvant systemic treatment of premenopausal women with early breast cancer focusing on the optimal chemotherapy, endocrine therapy, and targeted therapy approaches in this specific patient population.

Improving Adjuvant Endocrine Treatment Tailoring in Premenopausal Women With Hormone Receptor-Positive Breast Cancer

The Oncology Grand Rounds series is designed to place original reports published in the Journal into clinical context. A case presentation is followed by a description of diagnostic and management challenges, a review of the relevant literature, and a summary of the authors' suggested management approaches. The goal of this series is to help readers better understand how to apply the results of key studies, including those published in Journal of Clinical Oncology, to patients seen in their own clinical practice.

Incidence and Survival Among Young Women With Stage I-III Breast Cancer: SEER 2000-2015

Background

Although recent findings suggest that de novo stage IV breast cancer is increasing in premenopausal women in the United States, contemporary incidence and survival data are lacking for stage I-III cancer.

Methods

Women aged 20-29 (n = 3826), 30-39 (n = 34 585), and 40-49 (n = 126 552) years who were diagnosed with stage I-III breast cancer from 2000 to 2015 were identified from the Surveillance, Epidemiology, and End Results 18 registries database. Age-adjusted, average annual percentage changes in incidence and 5- and 10-year Kaplan-Meier survival curves were estimated by race and ethnicity, stage, and hormone receptor (HR) status and grade (low to well and moderately differentiated; high to poorly and undifferentiated) for each age decade.

Results

The average annual percentage change in incidence was positive for each age decade and was highest among women aged 20-29 years. Increased incidence was driven largely by HR+ cancer, particularly HR+ low-grade cancer in women aged 20-29 and 40-49 years. By 2015, incidence of HR+ low- and high-grade cancer each independently exceeded incidence of HR- cancer in each age decade. Survival for HR+ low- and high-grade cancer decreased with decreasing age; survival for HR- cancer was similar across age decades. Among all women aged 20-29 years, 10-year survival for HR+ high-grade cancer was lower than that for HR+ low-grade or HR- cancer. Among women aged 20-29 years with stage I cancer, 10-year survival was lowest for HR+ high-grade cancer.

Conclusions

HR+ breast cancer is increasing in incidence among premenopausal women, and HR+ high-grade cancer was associated with reduced survival among women aged 20-29 years. Our findings can help guide further evaluation of preventive, diagnostic, and therapeutic strategies for breast cancer among premenopausal women.

Nonadherent behaviors among young women on adjuvant endocrine therapy for breast cancer

BACKGROUND

Young age is a known factor associated with suboptimal adherence to endocrine therapy (ET) for adjuvant breast cancer (BC) treatment. This study was aimed at assessing nonadherent behaviors and associated factors among young women with early-stage hormone receptor-positive BC.

METHODS

As part of a multicenter, prospective cohort of women with a diagnosis of BC at or under the age of 40 years, participants were surveyed 30 months after their diagnosis about adherent behaviors. Among those who reported taking ET, adherence was measured with a 3-item Likert-type scale: Do you ever forget to take your ET? If you feel worse when you take your ET, do you stop taking it? Did you take your ET exactly as directed by your doctor over the last 3 months? Women reporting at least 1 nonadherent behavior were classified as nonadherers. Variables with a P value <.20 were included in a multivariable logistic model.

RESULTS

Among 384 women, 194 (51%) were classified as nonadherers. Univariate factors that retained significance in the multivariable model included educational level (odds ratio [OR], 0.50 for high vs low; P = .04), level of social support according to the Medical Outcome Study Social Support Survey (OR, 0.98 per 1 point; P = .01), and confidence with the decision regarding ET measured on a 0 to 10 numerical scale (OR, 0.63 for high vs low; P = .04).

CONCLUSIONS

Findings from this study could help to identify young patients at higher risk for nonadherence. Interventions adapted to the level of education and aimed at reinforcing support and patients' confidence in their decision to take ET could improve adherence and associated outcomes in this population.

Acceptability of Localized Cancer Risk Reduction Interventions Among Individuals at Average or High Risk for Cancer

Individuals at high risk for cancer, including those already diagnosed with premalignant lesions, can potentially benefit from chemopreventive interventions to reduce cancer risk. However, uptake and acceptability have been hindered due to the risk of systemic toxicity and other adverse effects. Locally delivered chemopreventive agents, where direct action on the primary organ may limit systemic toxicity, are emerging as an option for high-risk individuals. While a number of clinical trials support the development of chemopreventive agents, it is crucial to understand the factors and barriers that influence their acceptability and use. We conducted 36 focus groups with 198 individuals at average and high risk of breast/ovarian, gynecologic, and head/neck/oral and lung cancers to examine the perceptions and acceptability of chemopreventive agents. Participants' willingness to use chemopreventive agents was influenced by several factors, including perceived risk of cancer, skepticism around prevention, previous knowledge of chemopreventive agents, support from trusted sources of health information, participation in other cancer-related risk-reduction activities, previous experience with similar modalities, cost, regimen, side effects, and perceived effectiveness of the preventive intervention. Our findings indicate that individuals may be more receptive to locally delivered chemopreventive agents if they perceive themselves to be at high risk for cancer and are given the necessary information regarding regimen and side effects to make an informed decision. Clinical trials that collect additional patient-centered data including side effects and how these interventions fit into an individual's lifestyle are imperative to improve uptake of chemopreventive agents.

Adherence to adjuvant endocrine therapy in postmenopausal breast cancer patients: A 5-year prospective study

PURPOSE

Adjuvant endocrine therapy (ET) in breast cancer reduces recurrence risk and increases overall survival. The aim of the study was to quantify non-adherence and discontinuation to ET in postmenopausal women with breast cancer, and identify possible clinical or social risk factors.

METHODS

Women with hormone-receptor positive breast cancer (N = 138), mean age 58 (SD 9.3) years, filled in 4 questionnaires within 1-12, 24, 36 and 48-60 months after surgery; Subjective Health Complaints Inventory (SHC), Functional Assessment of Cancer Therapy-Social Support Subscale (FACT-ES), and Quality of Patient Information Questionnaire (QPI). Adherence to Tamoxifen (Tam) or Aromatase Inhibitors (AI) was examined using self-reported adherence and data from the Norwegian Prescription Database (NorPD) [corrected]. Kaplan-Meier curves and Cox proportional hazards regression models estimated adherence to ET.

RESULTS

The estimate of discontinued ET within 60 months was 38%. Self-reported discontinuation was 7% compared with 25% from the NorPD. Being overweight or obese were significantly time dependent factors predictive for discontinuing ET, p = 0.025.

CONCLUSION

Closer follow-ups, tailor-made information about the proven benefits of ET, and keeping a normal body mass index (BMI) may improve adherence to ET in postmenopausal women with breast cancer.

Improving adherence to endocrine hormonal therapy among breast cancer patients: Study protocol for a randomized controlled trial

Adjuvant endocrine hormonal therapy (EHT) is highly effective and appropriate for nearly all breast cancer patients with hormone receptor-positive tumors, which represent 75% of all breast cancer diagnoses. Long-term use of EHT reduces recurrence rates and nearly halves the risk of death during the second decade after diagnosis. Despite the proven benefits, about 33% of women receiving EHT do not take their medication as prescribed. This causes an increase in the risk for recurrence and death.

To promote adherence to EHT among breast cancer patients, this study will develop and pilot-test an intervention consisting of 1) a bilingual, culturally tailored, personalized, interactive smartphone application (app); and 2) support from a patient navigator. The control group will receive usual care. This 2-group randomized control trial will recruit 120 breast cancer patients receiving EHT at the Mays Cancer Center at UT Health San Antonio. The two-year study will have 3-time assessments (baseline, 3 and 6 months).

This theory-based intervention will empower patients' self-monitoring and management. It will facilitate patient education, identification/reporting of side effects, delivery of self-care advice, and simplify communication between the patient and the oncology team. The ultimate goal of this innovative multi-communication intervention is to improve overall survival and life expectancy, enhance quality of life, reduce recurrence, and decrease healthcare cost. The anticipated outcome is a scalable, evidence-based, and easily disseminated intervention with potentially broad use to patients using EHT and other oral anticancer agents.

Determinants of non-adherence to adjuvant endocrine treatment in women with breast cancer: the role of comorbidity

PURPOSE

To examine factors associated with non-adherence during 5 years of endocrine treatment, including the possible influence of comorbidity burden and specific medical conditions.

METHODS

From all women diagnosed with stage I-III, ER-positive breast cancer in Stockholm-Gotland, Uppsala-Örebro and Northern Sweden between 2006 and 2009, we included 4645 women who had at least one dispensation of tamoxifen or aromatase inhibitors (AIs) and 5 years of follow-up without distant recurrence. A medical possession ratio of < 80% was used to define non-adherence. Logistic regression was used to estimate odds ratios (ORs) and 95% confidence intervals (CIs) of non-adherence.

RESULTS

During follow-up, 977 (21%) women became non-adherents. Non-adherence was associated with greater comorbidity burden assessed by Charlson comorbidity index (CCI) during follow-up (OR 1.43; 95% CI 1.08-1.88 for ≥ 2 additional scores compared to 0), pre-diagnostic HRT use (OR 1.99; 1.58-2.49), not married (OR 1.42; 1.23-1.64), high educational level (OR 1.25; 1.02-1.53 compared to lowest level), and use of symptom-relieving drugs. HER-2 positivity (OR 0.61; 0.45-0.81) and adjuvant chemotherapy (OR 0.42; 0.35-0.52) were associated with lower odds of non-adherence. Similar patterns were observed for the presence of lymph node metastasis, higher tumour grade, and use of AIs compared to tamoxifen. Myocardial infarction and chronic pulmonary disease was suggested as leading conditions associated with non-adherence in women with increasing CCI.

CONCLUSION

We identified subgroups of women with breast cancer at increased risk of non-adherence. Our findings related to comorbidity suggest the importance of focusing on the presence of specific co-existing conditions when monitoring adherence.

Understanding adjuvant endocrine therapy persistence in breast Cancer survivors

Background

Adjuvant endocrine therapy (AET) significantly decreases the risk of breast cancer recurrence and mortality. Notwithstanding the demonstrated efficacy of AET, 31–73% of breast cancer survivors do not persist with AET. The purpose of this study was to explore breast cancer survivors’ experiences and perspectives of persisting with AET and to identify the psychosocial and healthcare system factors that influence AET persistence.

Methods

Informed by interpretive descriptive methodology and relational autonomy theory, individual interviews were conducted with 22 women diagnosed with early-stage breast cancer who had been prescribed AET. These participants also completed a demographic form and a survey that assessed their perceived risk of recurrence. Interviews were analysed using inductive thematic and constant comparative analysis to iteratively compare data and develop conceptualizations of the relationships among data. Descriptive statistics were used to summarize the quantitative data.

Results

The personal, social, and structural factors found to influence AET persistence included AET side effects, perception of breast cancer recurrence risk, medication and necessity beliefs, social support, the patient-provider relationship, and the continuity and frequency of follow-up care. For most women, over time, the decision-making process around AET persistence became a balancing act between quality of life and quantity of life. The interplay between the personal, social, and structural factors was complex and the weight women placed on some factors over others influenced their AET persistence or non-persistence.

Conclusion

Expanding our understanding of the factors affecting breast cancer survivors’ AET persistence from their perspective is the first step in developing efficacious, patient-centered interventions aimed at improving AET persistence. In order to improve AET persistence, enhanced symptom management is required, as well as the development of supportive care strategies that acknowledge the values and beliefs held by breast cancer survivors while reinforcing the benefits of AET, and addressing women’s reasons for non-persistence. Improved continuity of health care and patient-healthcare provider communication across oncology and primary care settings is also required. The development and evaluation of supportive care strategies that address the challenges associated with AET experienced by breast cancer survivors hold the potential to increase both women’s quality and quantity of life.

Electronic supplementary material

The online version of this article (10.1186/s12885-018-4644-7) contains supplementary material, which is available to authorized users.

Personal and clinical social support and adherence to adjuvant endocrine therapy among hormone receptor-positive breast cancer patients in an integrated health care system

PURPOSE

We evaluated associations between personal and clinical social support and non-adherence to adjuvant endocrine therapy (AET) in a large, Northern California breast cancer (BC) cohort from an integrated healthcare network.

METHODS

This study included 3382 women from the Pathways Study diagnosed from 2005 to 2013 with stages I-III hormone receptor-positive BC and who responded to the Medical Outcomes Study Social Support and Interpersonal Processes of Care surveys, approximately 2 months post-diagnosis. We used logistic regression to evaluate associations between tertiles of social support and non-initiation (< 2 consecutive prescription fills within a year after diagnosis). Among those who initiated treatment, we used proportional hazards regression to evaluate associations with discontinuation (≥ 90 day gap) and non-adherence (< 80% medical possession ratio).

RESULTS

Of those who initiated AET (79%), approximately one-fourth either discontinued AET or were non-adherent. AET non-initiation was more likely in women with moderate (adjusted OR 1.18, 95% CI 0.96-1.46) or low (OR 1.30, 95% CI 1.05-1.62) versus high personal social support (P trend = 0.02). Women with moderate (HR 1.20, 95% CI 0.99-1.45) or low (HR 1.32, 95% CI 1.09-1.60) personal social support were also more likely to discontinue treatment (P trend = 0.01). Furthermore, women with moderate (HR 1.25, 95% CI 1.02-1.53) or low (HR 1.38, 95% CI 1.12-1.70) personal social support had higher non-adherence (P trend = 0.007). Associations with clinical social support and outcomes were similar. Notably, high clinical social support mitigated the risk of discontinuation when patients' personal support was moderate or low (P value = 0.04).

CONCLUSIONS

Women with low personal or clinical social support had higher AET non-adherence. Clinician teams may need to fill support gaps that compromise treatment adherence.

A tissue microRNA signature that predicts the prognosis of breast cancer in young women

Since breast cancers in young women are generally aggressive, young patients tend to be intensively treated with anti-cancer drugs. To optimize the strategy for treatment, particularly in young women, prognostic biomarkers are urgently required. The objective of this study was to identify a tissue microRNA (miRNA) signature that predicts prognosis in young breast cancer patients. Total RNA from 45 breast cancer patients aged <35 years was extracted from formalin-fixed paraffin-embedded (FFPE) tissues and analyzed using miRNA microarrays. Patients were categorized into two groups according to recurrence status within the 5 year period after surgery: recurrence (n = 11) and non-recurrent (n = 34). Histological parameters of hormone receptors and Ki-67 were statistically compared between the two groups. Differentially expressed miRNAs were identified, and their associations with overall survival (OS) were evaluated by log-rank test. The median observation period was 5.8 years for the recurrent group, and 9.1 years for the non-recurrent group. Nine miRNAs were significantly differentially expressed between the recurrent and non-recurrent groups. Receiver Operating Characteristic curve analysis was performed to evaluate the prediction accuracy of the identified miRNAs, and the resultant area under the curve was >0.7. Five of the miRNAs were validated by qRT-PCR, and the expression levels of three of those five (miR-183-5p, miR-194-5p, and miR-1285-5p), both alone and in combination, were associated with OS. In conclusion, we identified three candidate miRNAs that could be used separately or in combination as prognostic biomarkers in young breast cancer patients. This miRNA signature may enable selection of better treatment choices for young women with this disease.

Predicting Adherence to Aromatase Inhibitor Therapy among Breast Cancer Survivors: An Application of the Protection Motivation Theory

The purpose of this observational study was to determine if the Protection Motivation Theory could predict and explain adherence to aromatase inhibitor (AI) therapy among breast cancer survivors. Purposive sampling was used to identify 288 survivors who had been prescribed AI therapy. A valid and reliable survey was mailed to survivors. A total of 145 survivors completed the survey.

The Morisky scale was used to measure adherence to AI. The survivors reported a mean score of 6.84 (±0.66) on the scale. Nearly 4 in 10 survivors (38%) were non-adherent. Adherence differed by age, marital status, insurance status, income, and presence of co-morbid conditions. Self-efficacy (r=0.485), protection motivation (r=0.310), and Response Efficacy (r=0.206) were positively and significantly correlated with adherence. Response Cost (r=-0.235) was negatively correlated with adherence. The coping appraisal constructs were statistically significant predictors medication adherence (β=0.437) with self-efficacy being the strongest significant predictor of adherence (β = 0.429).

Barriers and facilitators of adjuvant hormone therapy adherence and persistence in women with breast cancer: a systematic review

PURPOSE

Nonadherence to hormone therapy in breast cancer survivors is common and associated with increased risk of mortality. Consistent predictors of nonadherence and nonpersistence are yet to be identified, and little research has examined psychosocial factors that may be amenable to change through intervention. This review aimed to identify predictors of nonadherence and nonpersistence to hormone therapy in breast cancer survivors in order to inform development of an intervention to increase adherence rates.

METHODS

Studies published up to April 2016 were identified through MEDLINE, Embase, Web of Science, PsycINFO, CINAHL and gray literature. Studies published in English measuring associations between adherence or persistence and any predictor variables were included. Eligible studies were assessed for methodological quality, data were extracted and a narrative synthesis was conducted.

RESULTS

Sixty-one eligible articles were identified. Most studies focused on clinical and demographic factors with inconsistent results. Some evidence suggested that receiving specialist care and social support were related to increased persistence, younger age and increased number of hospitalizations were associated with nonadherence, and good patient-physician relationship and self-efficacy for taking medication were associated with better adherence. A small amount of evidence suggested that medication beliefs were associated with adherence, but more high-quality research is needed to confirm this.

CONCLUSION

Some psychosocial variables were associated with better adherence and persistence, but the results are currently tentative. Future high-quality research should be carried out to identify psychosocial determinants of nonadherence or nonpersistence that are modifiable through intervention.

Challenges in Treating Premenopausal Women with Endocrine-Sensitive Breast Cancer

For the hundreds of thousands of premenopausal women who are diagnosed annually with endocrine-sensitive breast cancer, treatment strategies are complex. For many, chemotherapy may not be necessary, and endocrine therapy decision making is paramount. Options for adjuvant endocrine regimens include tamoxifen for 5 years, tamoxifen for 10 years, ovarian function suppression (OFS) plus tamoxifen for 5 years, and OFS plus an aromatase inhibitor for 5 years. There are modest differences in efficacy between these regimens, with a benefit from OFS most obvious among patients with higher-risk disease; therefore, choosing which should be used for a given patient requires consideration of expected toxicities and patient preferences. An aromatase inhibitor cannot be safely prescribed without OFS in this setting. Additional research is needed to determine whether genomic tests such as Prosigna and Endopredict can help with decision making about optimal duration of endocrine therapy for premenopausal patients. Endocrine therapy side effects can include hot flashes, sexual dysfunction, osteoporosis, and infertility, all of which may impair quality of life and can encourage nonadherence with treatment. Ovarian function suppression worsens menopausal side effects. Hot flashes tend to be worse with tamoxifen/OFS, whereas sexual dysfunction and osteoporosis tend to be worse with aromatase inhibitors/OFS. Pregnancy is safe after endocrine therapy, and some survivors can conceive naturally. Still, embryo or oocyte cryopreservation should be considered at the time of diagnosis for patients with endocrine-sensitive disease who desire future childbearing, particularly if they will undergo chemotherapy.

Family-building After Breast Cancer: Considering the Effect on Adherence to Adjuvant Endocrine Therapy

Adherence to endocrine therapy (ET) is a longstanding problem in breast cancer (BC) survivorship care, particularly among younger women. Younger patients have reported lower ET initiation rates and greater rates of early discontinuation and are considered an "at risk" group for nonadherence. For women who hope to have children in the future, concerns about premature menopause and the implications of postponing childbearing for the 5 to 10 years of ET are widespread. Preliminary evidence suggests that prioritizing fertility, along with concerns about side effects, leads to ET noninitiation and early discontinuation. Clinical efforts to improve adherence might need to consider patients' family-building goals during the course of treatment and to appropriately counsel patients according to their priorities and family-building intentions. Educational materials about family building after cancer are still not consistently available or provided. Helping patients to access trusted informational resources and decision support tools, in conjunction with medical counseling, will promote informed decisions regarding ET adherence and pregnancy that are medically appropriate. Such shared patient-provider decision-making about ET adherence and pregnancy could help to maximize patient autonomy by incorporating their values, preferences, and priorities into decisions, using providers' medical expertise.

Cancer Care Coordinators to Improve Tamoxifen Persistence in Breast Cancer: How Heterogeneity in Baseline Prognosis Impacts on Cost-Effectiveness

OBJECTIVES

To assess the cost-effectiveness of a cancer care coordinator (CCC) in helping women with estrogen receptor positive (ER+) early breast cancer persist with tamoxifen for 5 years.

METHODS

We investigated the cost-effectiveness of a CCC across eight breast cancer subtypes, defined by progesterone receptor (PR) status, human epidermal growth factor receptor 2 (HER2) status, and local/regional spread. These subtypes range from excellent to poorer prognoses. The CCC helped in improving tamoxifen persistence by providing information, checking-in by phone, and "troubleshooting" concerns. We constructed a Markov macrosimulation model to estimate health gain (in quality-adjusted life-years or QALYs) and health system costs in New Zealand, compared with no CCC. Participants were modeled until death or till the age of 110 years. Some input parameters (e.g., the impact of a CCC on tamoxifen persistence) had sparse evidence. Therefore, we used estimates with generous uncertainty and conducted sensitivity analyses.

RESULTS

The cost-effectiveness of a CCC for regional ER+/PR-/HER2+ breast cancer (worst prognosis) was NZ $23,400 (US $15,800) per QALY gained, compared with NZ $368,500 (US $248,800) for local ER+/PR+/HER2- breast cancer (best prognosis). Using a cost-effectiveness threshold of NZ $45,000 (US $30,400) per QALY, a CCC would be cost-effective only in the four subtypes with the worst prognoses.

CONCLUSIONS

There is value in investigating cost-effectiveness by different subtypes within a disease. In this example of breast cancer, the poorer the prognosis, the greater the health gains from a CCC and the better the cost-effectiveness. Incorporating heterogeneity in a cost-utility analysis is important and can inform resource allocation decisions. It is also feasible to undertake in practice.

Persistence to 5-year hormonal breast cancer therapy: a French national population-based study

Background:

Non-persistence to oral hormonal therapy (HT) in breast cancer (BC) is an emerging health issue, and estimations vary according to the population selected and/or the statistical method applied. This study aimed to estimate non-persistence over 5 years to HT in an unselected sample of women with BC using a French national population-based database and accounting for competing risks.

Methods:

A retrospective cohort of 600 women initiating a HT between 2006 and 2007 was constituted using a representative sample of the French national healthcare insurance system database. The Cumulative Incidence Function method was used to estimate the probability of first treatment discontinuation of at least 90 days accounting for competing risk of death from any cause over the theoretical 5-year period of treatment.

Results:

Thirty one percent of patients who initiated a HT were identified as non-persistent at the fifth year of follow-up. Patients who switched to another HT (HR 3.10, 95% CI (2.20; 4.36)) or had metastatic BC (HR 3.07, 95% CI (1.73; 5.46)) were more likely to be non-persistent. Women who initiated aromatase inhibitors as compared with tamoxifen (HR 0.62, 95% CI (0.46; 0.83)), had administrative registration for BC (HR 0.21, 95% CI (0.13; 0.32)), or had received an adjuvant chemotherapy (HR 0.65, 95% CI (0.48; 0.89)) were less likely to discontinue.

Conclusions:

The estimate of long-term non-persistence in an unselected sample of women treated in France by oral hormonal therapy is substantial, even accounting for competing risks.

Subtype-Dependent Relationship Between Young Age at Diagnosis and Breast Cancer Survival

PURPOSE

Young women are at increased risk for developing more aggressive subtypes of breast cancer. Although previous studies have shown a higher risk of breast cancer recurrence and death among young women with early-stage breast cancer, they have not adequately addressed the role of tumor subtype in outcomes.

METHODS

We examined data from women with newly diagnosed stage I to III breast cancer presenting to one of eight National Comprehensive Cancer Network centers between January 2000 and December 2007. Multivariable Cox proportional hazards models were used to assess the relationship between age and breast cancer-specific survival.

RESULTS

A total of 17,575 women with stage I to III breast cancer were eligible for analysis, among whom 1,916 were ≤ 40 years of age at diagnosis. Median follow-up time was 6.4 years. In a multivariable Cox proportional hazards model controlling for sociodemographic, disease, and treatment characteristics, women ≤ 40 years of age at diagnosis had greater breast cancer mortality (hazard ratio [HR], 1.4; 95% CI, 1.2 to 1.7). In stratified analyses, age ≤ 40 years was associated with statistically significant increases in risk of breast cancer death among women with luminal A (HR, 2.1; 95% CI, 1.4 to 3.2) and luminal B (HR 1.4; 95% CI, 1.1 to 1.9) tumors, with borderline significance among women with triple-negative tumors (HR, 1.4; 95% CI, 1.0 to 1.8) but not among those with human epidermal growth factor receptor 2 subtypes (HR, 1.2; 95% CI, 0.8 to 1.9). In an additional model controlling for detection method, young age was associated with significantly increased risk of breast cancer death only among women with luminal A tumors.

CONCLUSION

The effect of age on survival of women with early breast cancer seems to vary by breast cancer subtype. Young age seems to be particularly prognostic in women with luminal breast cancers.