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

A prospective, multicenter, randomized, double-blind placebo-controlled trial on purified and specific Cytoplasmic pollen extract for hot flashes in breast cancer survivors

OBJECTIVE

evaluate the efficacy and tolerability of PureCyTonin against hot flashes (HF) in breast cancer survivors (BCS).

METHODS

a prospective, multicenter, randomized, double-blind placebo-controlled trial was conducted in Italy.

INTERVENTIONS

administration of PureCyTonin or placebo, for 3 months. Effectiveness was investigated through the compilation of a daily diary for HF and of validated questionnaires (Menopause Rating Scale (MRS), Pittsburgh Sleep Quality Index (PSQI), Visual Analogical Scales (VAS) for HF, sweating, irritability, fatigue, sleep, quality of life), carried out before starting the treatment (T0), after 1 month (T1) and after 3 months (T2). Any side effects and HF diary were recorded at each visit.

RESULTS

19 women were randomized to receive PureCyTonin and 20 to placebo. At T2 compared to T0, in the PureCyTonin group, we found a reduction in the number of HF (p = 0.02) measured by daily diary. An improvement in the subjective perception of women regarding HF intensity (p = 0.04), sweat nuisance (p = 0.02), irritability (p = 0.03) and fatigue (p = 0.04) was observed through VAS scale measurement at T2 compared to T0.The total MRS score was significantly better in the PureCyTonin group at T1 (p = 0.03) compared to T0.

CONCLUSIONS

PureCyTonin significantly reduces HF number after 3 months of therapy in BCS and it is well-tolerated.

Familial adversity: association with discontinuation of adjuvant hormone therapy and breast cancer prognosis

BACKGROUND

Many studies have examined patient-related factors affecting adjuvant hormone therapy adherence in patients with breast cancer. Our study aimed to examine associations of family-related factors with adjuvant hormone therapy discontinuation and breast cancer-specific mortality.

METHODS

By cross-linking 7 Swedish health registers, we performed a cohort study that included all patients with breast cancer who initiated adjuvant hormone therapy during 2006-2019 in Sweden (N = 10 701). A group-based multitrajectory model was used to identify familial adversity groups based on 3 dimensions: material deprivation, negative family dynamics, and loss or threat of loss. Cox proportional hazard models were used to investigate associations of familial adversity with hormone therapy discontinuation and breast cancer-specific mortality.

RESULTS

We identified 5 distinctive familial adversity groups among the cohort participants. Compared with women who had low familial adversity, higher risks to discontinue adjuvant hormone therapy were observed among women with material deprivation (hazard ratio [HR] = 1.31, 95% confidence interval [CI] = 1.20 to 1.43), negative family dynamics (HR = 1.16, 95% CI = 1.06 to 1.28), loss or threat of loss (HR = 1.15, 95% CI = 1.00 to 1.32), or high familial adversity (HR = 1.53, 95% CI = 1.40 to 1.68). Furthermore, women with material deprivation (HR = 1.37, 95% CI = 1.05 to 1.79), negative family dynamics (HR = 1.41, 95% CI = 1.01 to 1.97), or high adversity (HR = 1.67, 95% CI = 1.26 to 2.23) were at higher risk of dying from breast cancer.

CONCLUSION

Familial adversity is associated with a higher risk of adjuvant hormone therapy discontinuation and breast cancer-specific mortality. Family-related factors identified in our study may help identify high-risk patients for interventions to prevent treatment discontinuation and subsequently improve breast cancer outcomes.

Symptoms and need for individualised support during the first year after primary treatment for breast cancer-A qualitative study

BACKGROUND

The survival rate among patients with breast cancer is high. It is well described that after primary treatment patients may experience symptoms and concerns but the needs and resources during the first year to manage everyday life are not well described.

AIM

To describe experiences of symptom distress, needs and support during the first year after primary treatment for breast cancer from the perspectives of patients and healthcare professionals.

DESIGN

Qualitative descriptive.

METHODS

Data collection through individual interviews with patients (n = 17) and a focus group interview with healthcare professionals (n = 7). Data was analysed using thematic analysis and resulted in three themes.

RESULTS

The first theme, 'Struggling with symptoms and changes in everyday life' shows how symptoms and concerns interfered with the everyday life of patients and in some situations even impeded them. Patients try to adapt to their new situation by creating new routines and managing symptoms through self-care. The second theme, 'Adaption in a period of uncertainty' describes thoughts about cancer recurrence and doubts about continuing with the endocrine therapy if symptoms prolong. In the third theme, 'Support and need for individualized follow-up care' healthcare professionals described that they provide support by being available and by giving both verbal and written information. Patients expressed that the information could be too general and voiced a need for more individually tailored support.

CONCLUSION

During the first year after primary treatment, patients with breast cancer describe how they try to manage by themselves, but express both unmet needs and a wish for extended and more individually tailored support. The healthcare professionals recognised that patients lack a structured plan for the first year and the need for continued support. This stresses a need for development of care models with special consideration towards individualised support after breast cancer treatment.

NO PATIENT OR PUBLIC CONTRIBUTION

There was no patient or public involvement in the design or conduct of the study. The interview study was not considered to benefit from involving patients or healthcare professionals when designing the interview guides as they were developed through literature and previous research of patients treated for breast cancer.

Development and application of a weighted change score to evaluate interventions for vasomotor symptoms in patients with breast cancer using regression trees: a cohort study

PURPOSE

Vasomotor symptoms (VMS) are common among individuals with breast cancer (BC) and poorly managed symptoms are associated with reduced quality of life, treatment discontinuation, and poorer breast cancer outcomes. Direct comparisons among therapies are limited, as prior studies evaluating VMS interventions have utilized heterogeneous change measures which may not fully assess the perceived impact of change in VMS severity.

METHODS

We performed a prospective study where BC patients chose one of four categories of interventions to manage VMS. Change in VMS severity at 6 weeks was assessed using the validated Hot Flush Rating Scale (HFRS). A novel weighted change score integrating baseline symptom severity and directionality of change was computed to maximize the correlation between the change score and a perceived treatment effectiveness score. Variables influencing change in VMS severity were included in a regression tree to model factors influencing the weighted change score.

RESULTS

100 baseline and follow-up questionnaires assessing VMS were completed by 88 patients. Correlations between treatment effectiveness and VMS outcomes strengthened following adjustment for baseline symptoms. Patients with low VMS severity at baseline did not perceive change in treatment effectiveness. Intervention category was predictive of change in HFRS at 6 weeks.

CONCLUSION

Baseline symptom severity and the directionality of change (improvement or deterioration of symptoms) influenced the perception of clinically meaningful change in VMS severity. Future interventional studies utilizing the weighted change score should target moderate-high baseline severity patients.

Pilot randomized controlled trial of a program to enhance experience and adherence with adjuvant endocrine therapy among women with non-metastatic breast cancer: 12-month quantitative results

PURPOSE

Adjuvant endocrine therapy (AET) reduces recurrence risk after hormone receptor-positive breast cancer, but non-adherence is common. We pilot-tested SOIE, a program to enhance AET experience and adherence, to assess its acceptability, feasibility, and effects on psychosocial precursors of AET adherence.

METHODS

We conducted a 12-month pilot randomized controlled trial among women who had a first AET prescription. Intervention group received SOIE while control group received usual care. Psychosocial factors from the Theory of Planned Behavior (TPB) (intention - primary outcome -, attitude, subjective norm, behavioral control), additional constructs (AET knowledge, social support, coping planning), impact of AET services received, and adherence were measured by questionnaires at baseline, 3-month, and 12-month endpoints. Group patterns were compared using repeated measures analyses with generalized estimating equations.

RESULTS

A total of 106 women were randomized (participation = 54.9%; intervention n = 52; control n = 54; retention = 93.8%). Among SOIE women, ≥ 90% received the program components and were satisfied. Both groups scored high on adherence intentions and group patterns over time were not statistically different. In the intervention group, AET knowledge and coping planning with side effects increased (group-by-time p-value = .002 and .016), a higher proportion reported that AET services received helped them take their AET (p < .05) and have a consistent daily intake (p = .01).

CONCLUSION

SOIE is feasible and acceptable for survivors with an AET. SOIE did not significantly impact adherence intentions but was beneficial for other program outcomes and daily intake.

IMPLICATIONS FOR CANCER SURVIVORS

SOIE may represent an encouraging avenue to enhance supportive care and empower survivors with managing AET.

Mapping the Evidence on the Impact of mHealth Interventions on Patient-Reported Outcomes in Patients With Breast Cancer: A Systematic Review

PURPOSE

To comprehensively synthesize the existing evidence concerning mHealth interventions for patients with breast cancer (BC).

DESIGN

On July 30, 2023, we searched PubMed, PsycINFO, and Google Scholar for articles using the following inclusion criteria: evaluation of mHealth interventions in patients with cancer, at least 30 participants with BC, randomized control trials or prospective pre-post studies, determinants of health (patient-reported outcomes [PROs] and quality of life [QoL]) as primary outcomes, interventions lasting at least 8 weeks, publication after January 2015. Publications were excluded if they evaluated telehealth or used web-based software for desktop devices only. The quality of the included studies was analyzed with the Cochrane Collaboration Risk of Bias Tool and the Methodological Index for Non-Randomized Studies.

RESULTS

We included 30 studies (20 focused on BC), encompassing 5,691 patients with cancer (median 113, IQR, 135.5). Among these, 3,606 had BC (median 99, IQR, 75). All studies contained multiple interventions, including physical activity, tailored information for self-management of the disease, and symptom tracker. Interventions showed better results on self-efficacy (3/3), QoL (10/14), and physical activity (5/7). Lifestyle programs (3/3), expert consulting (4/4), and tailored information (10/11) yielded the best results. Apps with interactive support had a higher rate of positive findings, while interventions targeted to survivors showed worse results. mHealth tools were not available to the public in most of the studies (17/30).

CONCLUSION

mHealth interventions yielded heterogeneous results on different outcomes. Identifying lack of evidence on clinical scenarios (eg, patients undergoing systemic therapy other than chemotherapy) could aid in refining strategic planning for forthcoming research endeavors within this field.

Clinical factors associated with patterns of endocrine therapy adherence in premenopausal breast cancer patients

INTRODUCTION

Patients with hormone receptor positive breast cancer are recommended at least five years of adjuvant endocrine therapy, but adherence to this treatment is often suboptimal. We investigated longitudinal trends in adjuvant endocrine therapy (AET) adherence among premenopausal breast cancer patients and identified clinical characteristics, including baseline comorbidities and non-cancer chronic medication use, associated with AET adherence.

METHODS

We included stage I-III premenopausal breast cancer patients diagnosed during 2002-2011 and registered in the Danish Breast Cancer Group clinical database who initiated AET. We used group-based trajectory modeling to describe AET adherence patterns. We also linked patients to Danish population-based registries and fit multinomial logistic models to compute odds ratios (ORs) and 95% confidence intervals (95% CIs) associating clinical characteristics with AET adherence patterns.

RESULTS

We identified three adherence patterns among 4,353 women-high adherers (57%), slow decliners (36%), and rapid decliners (6.9%). Women with stage I disease (vs. stage II; OR: 1.9, 95% CI 1.5, 2.5), without chemotherapy (vs. chemotherapy; OR: 4.3, 95% CI 3.0, 6.1), with prevalent comorbid disease (Charlson Comorbidity Index score ≥ 1 vs. 0; OR: 1.6, 95% CI 1.1, 2.3), and with a history of chronic non-cancer medication use (vs. none; OR: 1.3, 95% CI 1.0, 1.8) were more likely to be rapid decliners compared with high adherers.

CONCLUSIONS

Women with stage I cancer, no chemotherapy, higher comorbidity burden, and history of chronic non-cancer medication use were less likely to adhere to AET. Taking steps to promote adherence in these groups of women may reduce their risk of recurrence.

Newly Diagnosed Mental Health Disorders in Patients With Breast Cancer Receiving Radiation Therapy

PURPOSE

Patients with a mental health disorder (MHD) have higher age-adjusted mortality compared with the general population. Few reports investigate factors contributing to MHD among patients with breast cancer receiving radiation therapy. We report the incidence of acquired MHD after the diagnosis of breast cancer and treatment with radiation therapy.

METHODS AND MATERIALS

Using a single institution, prospectively maintained database, we analyzed patients with breast cancer treated with radiation therapy between 2012 and 2017. We cross-referenced these patients with newly acquired International Classification of Diseases, Tenth Revision (ICD-10) MHD codes (F01-F99) within 3 years postbreast cancer diagnosis. The study included baseline National Comprehensive Cancer Network® (NCCN) distress tool scores and area deprivation index (ADI). Univariate and multivariable (MVA) Cox regression analyses were conducted to evaluate factors affecting new MHD onset.

RESULTS

Of the 967 included patients, 318 (33%) developed an MHD after their breast cancer diagnosis, which was predominately anxiety (45.1%) and depression (20.1%) related, with a median (IQR) time to diagnosis of 30 (24-33) months. Univariate analysis showed lymph node-positive disease, receipt of chemotherapy, receipt of a mastectomy, high comorbidity index, divorced status, retired status, and fourth-quartile ADI as significant predictors. On MVA, only receipt of chemotherapy (hazard ratio [HR], 1.70; P = .014) and divorced status (HR, 2.04; P = .009) remained significant. Fourth-quartile ADI, retired status, and high comorbidity index showed trends toward significance (HR, 1.78, P = .065; HR, 1.46, P = .094; HR, 1.41, P = .059, respectively). On MVA examining the effects of the radiation therapy type on MHD, whole breast with regional nodal irradiation (HR, 2.31, P = .015) and postmastectomy radiation therapy (HR, 1.88, P = .024) were both strong predictors of MHD development. Additionally, an NCCN distress tool score of >3 was also predictive of MHD onset.

CONCLUSIONS

In this cohort, 1 in 3 patients with localized breast cancer developed a new MHD, predominantly related to anxiety and depression. MHD risk was higher among divorced patients, those receiving chemotherapy, and patients receiving postmastectomy radiation therapy or whole breast with regional nodal irradiation. These findings highlight the importance of future studies and targeted interventions to support this vulnerable population.

Polypharmacy, over-the-counter medications, and aromatase inhibitor adherence in early-stage breast cancer

PURPOSE

Polypharmacy is associated with negative health outcomes and decreased medication adherence. Polypharmacy is common in cancer populations, but few studies have evaluated the relationship between polypharmacy and aromatase inhibitor (AI) adherence. No studies have evaluated the relationship between over-the-counter (OTC) supplements and AI adherence. Our primary hypothesis was that polypharmacy would be associated with increased risk of premature AI discontinuation.

METHODS

This exploratory analysis used data from the Exemestane and Letrozole Pharmacogenetics (ELPh) trial, a prospective, multicenter, randomized controlled trial that enrolled participants from 2005 to 2009. Included patients were female, postmenopausal, with stage 0-III breast cancer, who had completed indicated chemotherapy, surgery, and radiation. Participants were randomized to adjuvant exemestane or letrozole and completed serial clinical examinations and questionnaires for two years. Concomitant medication data were collected prospectively. Cox proportion models were used for statistical analysis of the relationship between polypharmacy, OTCs, medication class, and AI adherence.

RESULTS

In the 490 analyzed participants, use of any prescription medications at baseline was associated with decreased risk of premature AI discontinuation (HR 0.56, p = 0.02). Use of selective serotonin reuptake inhibitors (SSRIs) or selective serotonin and norepinephrine reuptake inhibitors (SNRIs) at baseline was associated with decreased risk of premature AI discontinuation (HR 0.67, p = 0.04). Use of any OTCs was not associated with AI discontinuation.

CONCLUSION

Baseline use of prescription medications but not OTCs was associated with increased AI persistence. Future research is needed to understand how this can be utilized to promote AI adherence.

Challenges in Obtaining and Seeking Information Among Breast Cancer Survivors in an Asian Country: a Qualitative Study

Breast cancer survivors on adjuvant endocrine therapy (AET) have distinct information-seeking experience compared to those in the diagnosis and intensive treatment phase. This study aimed to understand the challenges in obtaining and seeking information among Malaysian breast cancer survivors. We conducted semi-structured, one-to-one interviews among patients using AET from two hospitals and a local cancer organization. Interviews were conducted until theme saturation was achieved (N = 25). Interviews were de-identified, transcribed verbatim, and analysed using thematic analysis. To ensure rigor, coding was conducted through regular discussions between two researchers and the findings were shared with several participants after analysis was completed. Three main themes were identified: limitations in the healthcare system, pitfalls of seeking information online, and limited information from local sources. The participants perceived that their information needs were not met by their healthcare providers and sought information on the Internet to complement their information needs. However, they were faced with risks of misinformation, information overload, and unethical promotion of health products. Those with limited English proficiency had difficulties in accessing quality information, and suggested that there should be more content created by local health advocates in local languages, with information that is tailored for local cultures. As the Internet has become an important medium of health education, healthcare providers and patients should be equipped with the skills to share and search for information online. Digital health literacy needs to be incorporated in patient education modules to create a more informed and empowered patient community.

Effect of telehealth interventions on adherence to endocrine therapy among patients with breast cancer: a systematic review and meta-analysis

PURPOSE

To evaluate the effect of telehealth interventions on adherence to endocrine therapy among patients with breast cancer.

METHODS

A systematic search of five English databases (PubMed, Web of Science, Embase, the American Psychological Association PsycNet, and the Cochrane Library) and four Chinese databases (Chinese National Knowledge Infrastructure, SinoMed, WanFang Data, and WeiPu Data) was performed from inception to March 31, 2023. Two investigators independently screened the available studies for eligibility and extracted relevant data. Quality assessment was conducted using the Cochrane Risk of Bias Tool. The effect size was computed based on the risk ratio for dichotomous data and standardized mean difference for continuous data using Review Manager 5.4.

RESULTS

A total of 1,780 participants from eight randomized controlled trials were included. These studies involved treatment with aromatase inhibitors only (n = 3) or aromatase inhibitors plus tamoxifen (n = 5). Telehealth interventions involved web-based interventions, telephone-based interventions, interventions via mobile applications, and interventions based on technology. In three studies, subjective measures were used, while objective measures were utilized in another three. Two studies incorporated a combination of both subjective and objective measures. The duration of the interventions varied among studies, ranging from a week to 36 months. The follow-up duration ranged from 4 weeks to 36 months. The quality of included studies was moderate to high. The meta-analysis of the five studies reporting dichotomous data showed that telehealth interventions had a significant effect on adherence to endocrine therapy (RR = 0.86, 95% CI = 0.76-0.97). Moreover, four studies reported continuous data. The meta-analysis demonstrated that telehealth interventions significantly improved adherence to endocrine therapy at 1 month (SMD = 0.50, 95% CI = 0.10-0.90), 3 months (SMD = 0.58, 95% CI = 0.17-0.99), and 6 months (SMD = 0.27, 95% CI = 0.08-0.47) of follow-up.

CONCLUSION

Telehealth interventions may facilitate adherence to endocrine therapy among patients with breast cancer. Further research should adopt a theory-based design and explore the longer-term effects.

Identifying determinants of adherence to adjuvant endocrine therapy following breast cancer: A systematic review of reviews

BACKGROUND

In oestrogen-receptor positive breast cancer, daily oral adjuvant endocrine therapy (ET) for at least 5 years significantly reduces risks of recurrence and breast cancer-specific mortality. However, many women are poorly adherent to ET. Development of effective adherence support requires comprehensive understanding of influences on adherence. We undertook an umbrella review to identify determinants of ET adherence.

METHODS

We searched PubMed, Embase, CINAHL, PsycINFO, Cochrane and PROSPERO (inception to 08/2022) to identify systematic reviews on factors influencing ET adherence. Abstracted determinants were mapped to the World Health Organization's dimensions of adherence. Reviews were quality appraised and overlap assessed.

RESULTS

Of 5732 citations screened, 17 reviews were eligible (9 quantitative primary studies; 4 qualitative primary studies; 4 qualitative or quantitative studies) including 215 primary papers. All five WHO dimensions influenced ET non-adherence: The most consistently identified non-adherence determinants were patient-related factors (e.g. lower perceived ET necessity, more treatment concerns, perceptions of ET 'cons' vs. 'pros'). Healthcare system/healthcare professional-related factors (e.g. perceived lower quality health professional interaction/relationship) were also important and, to a somewhat lesser extent, socio-economic factors (e.g. lower levels of social/economic/material support). Evidence was more mixed for medication-related and condition-related factors, but several may be relevant (e.g. experiencing side-effects, cost). Potentially modifiable factors are more influential than non-modifiable/fixed factors (e.g. patient characteristics).

CONCLUSIONS

The evidence-base on ET adherence determinants is extensive. Future empirical studies should focus on less well-researched areas and settings. The determinants themselves are numerous and complex in indicating that adherence support should be multifaceted, addressing multiple determinants.

Effects of Reishimmune-S, a Fungal Immunomodulatory Peptide Supplement, on the Quality of Life and Circulating Natural Killer Cell Profiles of Patients With Early Breast Cancer Receiving Adjuvant Endocrine Therapy

OBJECTIVES

To evaluate the effects of Reishimmune-S, a fungal immunomodulatory peptide, on the quality of life (QoL) and natural killer (NK) cell subpopulations in patients receiving adjuvant endocrine therapy (ET) for breast cancer (BC).

METHODS

Patients who received adjuvant ET for stage I-III hormone receptor-positive BC without active infection were enrolled in this prospective pilot study. Reishimmune-S was administered sublingually daily for 6 months. QoL scores, circulating immune cell levels, including lymphocyte/NK cell subpopulations, and plasma levels of interleukin (IL)-6 and tumor necrosis factor (TNF)-α were measured at baseline and every 4 weeks. Data were analyzed using linear mixed-effect regression models.

RESULTS

Nineteen participants were included in the analyses. One patient with underlying asthma did not complete the study owing to the occurrence of skin rashes 15 days after the initiation of Reishimmune-S. No other adverse events were reported. Reishimmune-S supplementation significantly improved the cognitive function at 3 months and significantly decreased the fatigue and insomnia levels at 3 and 6 months, respectively. There was no significant change in the global health/QoL score between baseline and week 4 of treatment. The proportion of CD19+ lymphocytes was significantly higher at 3 and 6 months, and that of NKG2A+ and NKp30+ NK cells was significantly lower at 6 months than at baseline. In addition, fatigue positively correlated with the proportion of NKp30+ NK cells (β ± standard error: 24.48 ± 8.75, P = .007 in the mixed-effect model).

CONCLUSIONS

Short-term supplementation with Reishimmune-S affected the circulating immune cell composition and exerted positive effects on cognitive function, fatigue, and insomnia in patients with BC undergoing adjuvant ET, providing a potential approach for the management of treatment-related adverse reactions in this patient population.

Medication Adherence in Cancer Patients: A Comprehensive Review

Cancer is a complex disease that can affect different parts of the body. The rates of cancer have shown an increasing trend in the past decade. A majority of cancers are detected late, therefore becoming untreatable and resulting in significant mortality. Additionally, the lack of awareness about cancers, their risk factors, diagnostic modalities, and preventive measures contributes to increased burden among people. Despite significant developments in the therapeutic and comprehensive management of cancers, the cause for concern is the lack of medication adherence. This is majorly attributed to the adverse effects of the medication, the cost of the drugs, and other reasons. This review comprehensively discusses various aspects of cancer medication adherence that include therapeutic modalities for treating cancers, factors influencing medication adherence, barriers, and facilitators to medication adherence.

Predictive Models of Psychological Distress, Quality of Life, and Adherence to Medication in Breast Cancer Patients: A Scoping Review

Purpose

An interplay of clinical and psychosocial variables affects breast cancer patients' experiences and clinical trajectories. Several studies investigated the role of socio-demographic, clinical, and psychosocial factors in predicting relevant outcomes in breast cancer care, thus developing predictive models. Our aim is to summarize predictive models for specific psychological and behavioral outcomes: psychological distress, quality of life, and medication adherence. Specifically, we aim to map the determinants of the outcomes of interest, offering a thorough overview of these models.

Methods

Databases (PubMed, Scopus, Embase) have been searched to identify studies meeting the inclusion criteria: a breast cancer patients' sample, development/validation of a predictive model for selected psychological/behavioral outcomes (ie, psychological distress, quality of life, and medication adherence), and availability of English full-text.

Results

Twenty-one papers describing predictive models for psychological distress, quality of life, and adherence to medication in breast cancer were included. The models were developed using different statistical approaches. It has been shown that treatment-related factors (eg, side-effects, type of surgery or treatment received), socio-demographic (eg, younger age, lower income, and inactive occupational status), clinical (eg, advanced stage of disease, comorbidities, physical symptoms such as fatigue, insomnia, and pain) and psychological variables (eg, anxiety, depression, body image dissatisfaction) might predict poorer outcomes.

Conclusion

Predictive models of distress, quality of life, and adherence, although heterogeneous, showed good predictive values, as indicated by the reported performance measures and metrics. Many of the predictors are easily available in patients' health records, whereas others (eg, coping strategies, perceived social support, illness perceptions) might be introduced in routine assessment practices. The possibility to assess such factors is a relevant resource for clinicians and researchers involved in developing and implementing psychological interventions for breast cancer patients.

Optimal adjuvant therapy in older (≥70 years of age) women with low-risk early-stage breast cancer

Older women are under-represented in breast cancer (BC) clinical trials, and treatment guidelines are primarily based on BC studies in younger women. Studies uniformly report an increased incidence of local relapse with omission of breast radiation therapy. Review of the available literature suggests very low rates of distant relapse in women ≥70 years of age. The incremental benefit of endocrine therapy in decreasing rate of distant relapse and improving disease-free survival in older patients with low-risk BC remains unclear. Integration of molecular genomic assays in diagnosis and treatment of estrogen receptor positive BC presents an opportunity for optimizing risk-tailored adjuvant therapies in ways that may permit treatment de-escalation among older women with early-stage BC. The prevailing knowledge gap and lack of risk-specific adjuvant therapy guidelines suggests a compelling need for prospective trials to inform selection of optimal adjuvant therapy, including omission of adjuvant endocrine therapy in older women with low risk BC.

Omitting radiotherapy in elderly breast cancer patients: Valid strategy or illusory hope?

Breast cancer treatment strategies have evolved significantly over the years, and decisions regarding the use of radiotherapy have become increasingly complex. This paper explores the considerations and limitations associated with omitting radiotherapy as part of breast cancer treatment. While omitting radiotherapy may be a viable option for select patient groups, it is not without its challenges. The decision to omit radiotherapy in breast cancer treatment should be highly individualized and made after a comprehensive evaluation of the patient's specific circumstances.

Beliefs about medicines' association with endocrine therapy adherence in early breast cancer survivors in Croatia

This observational, cross-sectional study conducted at the University Hospital Centre Zagreb (UHC Zagreb) aimed to explore patients' beliefs about adjuvant endocrine therapy (AET) as well as their association with non-adherence and sociodemographic and clinical factors. Out of 420 early breast cancer (BC) patients included in the study, 79.5 % perceived AET necessary and important for their health, as measured by the Belief About Medicines Questionnaire (BMQ), with the mean necessity score (20.4 ± 3.68) significantly higher than the mean concerns score (13 ± 4.81) (p < 0.001). Based on the Medication Adherence Report Scale (MARS-5), 44.4 % (n = 182) of the participants were non-adherers, out of which 63.2 % (n = 115) were unintentional and 36.8 % (n = 67) intentional non-adherers. Significantly higher concern beliefs were found among patients that were younger (p < 0.001), employed (p < 0.001), intentionally non-adherent to AET (p = 0.006), had a lower body-mass index (p = 0.005) and a higher level of education (p < 0.001), were premenopausal at the time of diagnosis (p < 0.001), taking tamoxifen treatment (p = 0.05) and receiving ovarian suppression (p < 0.001). Younger patients should be recognized as being at risk of non-adherence as they hold greater concern beliefs about medicines.

Adherence to oral endocrine therapy in racial/ethnic minority patients with low socioeconomic status before and during the COVID-19 pandemic

BACKGROUND

Adherence to oral endocrine therapy (OET) is crucial in ensuring its maximum benefit in the prevention and treatment of hormone receptor-positive (HR +) breast cancer (BC). Medication use behavior is suboptimal especially in racial/ethnic minorities with lower socioeconomic status (SES).

AIM

We aimed to assess the impact of the coronavirus disease 2019 (COVID-19) pandemic on OET adherence and identify demographic and/or clinical characteristics associated with nonadherence in racial/ethnic minorities with lower SES.

METHOD

A retrospective study was conducted at the Harris Health System in Houston, Texas. Data were collected during the 6 months before and 6 months after the start of the pandemic. The adherence was assessed using the prescription refill data using the proportion of days covered. A multivariable logistic regression model was used to identify demographic/clinical characteristics associated with nonadherence. Eighteen years or older patients on appropriate doses of OET for prevention or treatment of BC were included.

RESULTS

In 258 patients, adherence was significantly lower during the pandemic (44%) compared to before the pandemic (57%). The demographic/clinical characteristics associated with OET nonadherence before the pandemic were Black/African American, obesity/extreme obesity, prevention setting, tamoxifen therapy, and 4 or more years on OET. During the pandemic, prevention setting and those not using home delivery were more likely to be nonadherent.

CONCLUSION

OET adherence was significantly reduced during the COVID-19 pandemic in racial/ethnic minority patients with low SES. Patient-centered interventions are necessary to improve OET adherence in these patients.

Prognostic impact of adjuvant endocrine therapy for estrogen receptor-positive and HER2-negative T1a/bN0M0 breast cancer

PURPOSE

Mammography screening has increased the detection of subcentimeter breast cancers. The prognosis for estrogen receptor (ER)-positive and human epidermal growth factor receptor 2 (HER2)-negative T1a/bN0M0 breast cancers is excellent; however, the necessity of adjuvant endocrine therapy (ET) is uncertain.

METHODS

We evaluated the effectiveness of adjuvant ET in patients with ER-positive and HER2-negative T1a/bN0M0 breast cancer who underwent surgery from 2008 to 2012. Standard ET was administrated after surgery. The primary endpoint was the cumulative incidence of distant metastasis. All statistical tests were 2-sided.

RESULTS

Adjuvant ET was administered to 3991 (83%) of the 4758 eligible patients (1202 T1a [25.3%] and 3556 T1b [74.7%], diseases). The median follow-up period was 9.2 years. The 9-year cumulative incidence of distant metastasis was 1.5% with ET and 2.6% without ET (adjusted subdistribution hazard ratio [sHR], 0.54; 95% CI, 0.32-0.93). In multivariate analysis, the independent risk factors for distant metastasis were no history of ET, mastectomy, high-grade, and lymphatic invasion. The 9-year overall survival was 97.0% and 94.4% with and without ET, respectively (adjusted HR, 0.57; 95% CI, 0.39-0.83). In addition, adjuvant ET reduced the incidence of ipsilateral and contralateral breast cancer (9-year rates; 1.1% vs. 6.9%; sHR, 0.17, and 1.9% vs. 5.2%; sHR, 0.33).

CONCLUSIONS

The prognosis was favorable in patients with ER-positive and HER2-negative T1a/bN0M0 breast cancer. Furthermore, adjuvant ET reduced the incidence of distant metastasis with minimal absolute risk difference. These findings support considering the omission of adjuvant ET, especially for patients with low-grade and no lymphatic invasion disease.

Are breast cancer patients with suboptimal adherence to cardiovascular treatment more likely to discontinue adjuvant endocrine therapy? Competing risk survival analysis in a nationwide cohort of postmenopausal women

BACKGROUND

High rates of discontinuation undermine the effectiveness of adjuvant endocrine therapy (AET) among hormone-receptive breast cancer patients. Patient prognosis also relies on the successful management of cardiovascular risk, which affects a high proportion of postmenopausal women. As with AET, adherence with cardiovascular drugs is suboptimal. We examined whether patient adherence with cardiovascular drugs was associated with the rate of AET discontinuation in a French nationwide claims database linked with hospitalisation data.

METHODS

We identified postmenopausal women starting AET between 01/01/2016 and 31/12/2020 and taking at least two drugs for the primary prevention of cardiovascular disease (antihypertensive drugs, lipid-lowering drugs and platelet aggregation inhibitors) before AET initiation. Adherence was assessed for each drug class by computing the proportion of days covered. Women were categorised as fully adherent, partially adherent or fully non-adherent with their cardiovascular drug regimen based on whether they adhered with all, part or none of their drugs. AET discontinuation was defined as a 90-day gap in AET availability. Time to AET discontinuation according to levels of cardiovascular drug adherence was estimated using cumulative incidence curves, accounting for the competing risks of death and cancer recurrence. Multivariate cause-specific Cox regressions and Fine-and-Gray regressions were used to assess the relative hazards of AET discontinuation.

RESULTS

In total, 32,075 women fit the inclusion criteria. Women who were fully adherent with their cardiovascular drugs had the lowest cumulative incidence of AET discontinuation at any point over the 5-year follow-up period. At 5 years, 40.2% of fully non-adherent women had discontinued AET compared with 33.5% of partially adherent women and 28.8% of fully adherent women. Both partial adherence and full non-adherence with cardiovascular drugs were predictors of AET discontinuation in the two models (cause-specific hazard ratios 1.16 [95% CI 1.10-1.22] and 1.49 [95% CI 1.39-1.58]; subdistribution hazard ratios 1.15 [95% CI 1.10-1.21] and 1.47 [95% CI 1.38-1.57]).

CONCLUSION

Clinicians should be aware that patients who do not adhere with their entire cardiovascular drug regimen are also more likely to discontinue AET. This stresses the importance of integrated care, as suboptimal adherence with both treatment components poses a threat to achieving ideal patient outcomes.

Barriers and Facilitators of Adherence to Oral Anticancer Medications Among Women with Breast Cancer: A Qualitative Study

Purpose

Despite the life-saving benefits of oral anticancer medications (OAMs) to women with breast cancer (BC), adherence remains suboptimal and, in many cases, not well documented. The study examined barriers and facilitators of adherence to OAMs among women receiving BC treatment in Nigeria.

Patients and Methods

The study was framed within the World Health Organization (WHO) Multidimensional Model of Adherence. We conducted qualitative in-depth interviews of 16 purposively sampled women in two tertiary hospitals in Southern Nigeria. The interviews were audio-recorded and transcribed verbatim. The interview data were analyzed using the Framework Method.

Results

The key barriers to OAM adherence mentioned were socioeconomic factors (high cost of medication) and therapy-related factors (medication side effects). The key facilitating mechanisms for adherence to OAMs mentioned included; (i) patient-related psychosocial factors such as self-encouragement and self-discipline in sticking to the prescription, taking the medication at a particular time each day, receiving practical support from family members; and (ii) healthcare team/system factors such as obtaining an adequate supply of the medication at the pharmacy.

Conclusion

Barriers and facilitators to OAM adherence are multidimensional. The study findings highlight the potential benefit of a multifaceted intervention (such as patient education and monitoring or strategies promoting cost-containment and side effects management) to optimize adherence. Therefore, our findings may inform the designing and evaluating of context-specific adherence measures and multifaceted intervention strategies targeting key barriers and approaches that enable adherence to enhance patient outcomes.

"Interventions to increase adherence to oral therapies in breast cancer patients: A systematic review based on the behavior change technique taxonomy"

OBJECTIVE

High rates of non-adherence to oral medications in breast cancer (BC) patients have been reported. Here we provide an up-to-date systematic review of the interventions aimed at increasing adherence to oral medication in BC patients, with a particular focus on the content of the interventions.

METHODS

PubMed, Scopus, Embase and Ovid databases and reference lists of relevant studies were searched through October 2022. Studies which (1) described an intervention aimed at increasing adherence to oral anticancer medication, (2) included (or planned to include) at least one sub-group of BC patients, (3) were written in English, and (4) with full-text available were included. The contents of the interventions were coded using the Behavior Change Technique Taxonomy. Quality assessment was conducted using Downs and Black scale.

RESULTS

Thirty-six studies met the inclusion criteria and involved a total sample of 28,528 BC patients. Interventions were mainly delivered with eHealth devices (n = 21) and most of them used mobile app. Other studies used in-person modalities (e.g., CBT, relaxation technique) or written materials (e.g., psycho-educational booklet). The behavior change techniques most frequently implemented were "problem solving," "social support," "information about health consequences," and "prompts/cues". Quality assessment revealed that the higher risk of bias refers to the selection process.

CONCLUSIONS

The use of reminders, monitoring patients' medication-taking behaviors and giving feedback were the most frequently implemented techniques in those interventions that resulted significant. If these preliminary observations were to be confirmed by future comparative studies, they should be taken into account when developing new interventions.

Stress appraisal and emotion regulation mediate the association between mindfulness and affect in cancer patients: Differential mechanisms for positive and negative affect

OBJECTIVE

Cancer patients are at an increased risk for affective problems, including feelings of anxiety and depression. Mindfulness has been linked to an array of benefits for affective functioning in various populations including cancer patients, but the mechanisms underlying this relationship are still poorly understood. Based on emotion-regulation and stress-coping models, this study examined the potential mediating role of stress appraisal and coping strategies in the associations between mindfulness and cancer patients' positive and negative affect.

METHODS

For this cross-sectional study, 245 cancer patients completed self-report questionnaires measuring mindfulness (FFMQ), positive and negative affect (PANAS), stress appraisal (SPSI-R:S), coping through positive reappraisal and positive refocusing (CERQ), rumination (RRQ), and distraction (COPE). Serial mediation analyses were conducted using the regression-based bootstrapping method.

RESULTS

Higher levels of mindfulness were associated with higher levels of positive affect; this relationship was mediated via stress appraisal and positive reappraisal. We also found an indirect effect from mindfulness directly via positive reappraisal to positive affect. In addition, higher levels of mindfulness were negatively associated with negative affect; this relationship was mediated via stress appraisal and rumination, with also an indirect effect from mindfulness directly via stress appraisal to negative affect.

CONCLUSIONS

Results suggest that stress appraisal and distinct coping strategies mediate the relationship between mindfulness and affect. Mindfulness may provide benefits for cancer patients' affect by allowing adaptive stress appraisal and ways of coping through more positive and less negative thinking.

Resistance to Resilience: Understanding Post-surgical Hormone Therapy in Breast Cancer Care

Breast cancer is one of the most common types of cancer affecting women worldwide. Over the years, breast cancer has become a major public health concern, and its incidence is rising globally. The treatment of breast cancer does not stop with surgical intervention, but adjuvant therapies are administered to improve patient outcomes post-surgery based on the type of breast cancer diagnosed. This review focuses on the value of hormone therapy (HT) in improving the prognosis of breast cancer patients and why adhering to adjuvant treatment post-surgery is difficult for patients. HT aims to reduce the chances of breast cancer recurrence after surgical treatment. Even though HT is life-saving, patients tend to not adhere to the therapy due to various factors such as side effects, age-related issues, and socioeconomic status. Most patients stop adhering to the therapy as the duration can be as long as 5-10 years, and the quality of life is greatly impacted due to the side effects of the treatment. This review examines the possible factors leading to non-adherence to HT and tries to propose possible interventions that might improve patient compliance with the treatment. This article not only focuses on the impact of side effects of HT on patients' quality of life but also tries to understand the problems faced by breast cancer patients in adhering to HT.

Medication Adherence in Patients with Hematologic Malignancies Who Are Hematopoietic Stem Cell Transplantation Survivors: A Qualitative Study

Medication adherence is critical for optimal health outcomes in patients with hematologic malignancies who have undergone allogeneic hematopoietic stem cell transplants (HSCT). However, this population struggles with medication nonadherence. Research that comprehensively describes the complex patient- and medication-related factors which impact medication adherence in this population is lacking. Hence, we used semistructured qualitative interviews to explore the diverse and complex factors contributing to medication adherence in HSCT recipients. We conducted 30 in-depth interviews with patients who were more than 180 days post-allogeneic HSCT at the Dana-Farber Cancer Institute. The interviews explored the physical, social, psychological, and sociodemographic factors that facilitate or discourage adherence to the post-transplantation medication regimen. Interviews were audio-recorded, transcribed, and coded using NVivo software. Two themes emerged that characterized the barriers patients face with their medication regimen. Patients reported factors outside of their control, such as managing multiple pharmacies, health insurance difficulties, and dosage timing, as significant barriers to medication adherence. Patients also reported barriers within their control, such as familial responsibilities. Important facilitators for medication adherence included caregiver and clinician support, previous experience managing a medication regimen, and tools that aid pill organization and timing. Furthermore, patients reported that although medication side effects and quantity of pills did not directly impact medication adherence, it increased their psychological distress. Facilitators and barriers to medication adherence can be physical, psychological, organizational, and social. There are many aspects of medication regimens that significantly increase patient distress. Hence, supportive interventions to improve medication adherence in patients undergoing HSCT may need to incorporate strategies to manage medication side effects and skills to improve psychological well-being and social support.

Endocrine Therapy for Surgeons: Practical Pearls for Managing Menopausal, Bone Loss and Sexual Adverse Effects

Breast cancer patients are living longer than ever before and as such the population of breast cancer survivors continues to grow. Approximately 80% of breast cancers are hormone receptor-positive (HR+) and most patients will receive neoadjuvant or adjuvant estrogen blockade, referred to as endocrine therapy. Although endocrine therapy reduces HR+ breast cancer recurrence by 30-50%, significant adverse effects pose a threat to treatment adherence. These adverse effects include vasomotor symptoms, colloquially referred to as hot flashes, bone loss, joint arthralgias, genitourinary syndrome of menopause (GSM), previously referred to as vaginal atrophy, and low libido. This review will present the evidence-based treatments available for each of these adverse effects, including clear treatment algorithms for GSM, which is often experienced by patients but overlooked by providers. The most important takeaway is to ask open-ended questions, encourage reporting of these symptoms, and refer patients to specialty providers as needed. Surgeons may be the first to encounter these symptoms, therefore it is critical to remain informed of the treatment options.

A Systematic Review and Meta-Analysis of Interventions to Promote Adjuvant Endocrine Therapy Adherence Among Breast Cancer Survivors

PURPOSE

Adjuvant endocrine therapy (AET) adherence among breast cancer survivors is often suboptimal, leading to higher cancer recurrence and mortality. Intervention studies to promote AET adherence have burgeoned, more than doubling in number since this literature was last reviewed. The current aim is to provide an up-to-date systematic review and meta-analysis of interventions to enhance AET adherence and to identify strengths and limitations of existing interventions to inform future research and clinical care.

METHODS

Systematic searches were conducted in three electronic databases. Studies were included in the systematic review if they examined an intervention for promoting AET adherence among breast cancer survivors. Studies were further included in the meta-analyses if they examined a measure of AET adherence (defined as compliance or persistence beyond initiation) and reported (or provided upon request) sufficient information to calculate an effect size.

RESULTS

Of 5,045 unique records, 33 unique studies representing 375,951 women met inclusion criteria for the systematic review. Interventions that educated patients about how to manage side effects generally failed to improve AET adherence, whereas policy changes that lowered AET costs consistently improved adherence. Medication reminders, communication, and psychological/coping strategies showed varied efficacy. Of the 33 studies that met the inclusion criteria for the systematic review, 25 studies representing 367,873 women met inclusion criteria for the meta-analysis. The meta-analysis showed statistically significant effects of the adherence interventions overall relative to study-specified control conditions (number of studies [k] = 25; odds ratio, 1.412; 95% CI, 1.183 to 1.682; P = .0001). Subgroup analyses showed that there were no statistically significant differences in effect sizes by study design (randomized controlled trial v other), publication year, directionality of the intervention (unidirectional v bidirectional contact), or intervention type.

CONCLUSION

To our knowledge, this is the first known meta-analysis to demonstrate a significant effect for interventions to promote AET adherence. The systematic review revealed that lowering medication costs and a subgroup of psychosocial and reminder interventions showed the most promise, informing future research, policy, and clinical directions.

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.

Assessing Adherence to Adjuvant Hormone Therapy in Breast Cancer Patients in Routine Clinical Practice

BACKGROUND

Adjuvant hormone therapy (HT) in patients with hormone receptor-positive breast cancer (BC) increases overall survival (OS). A lack of adherence to adjuvant endocrine therapy is common, 31.0-73.0% of women discontinue endocrine treatment before 5 years. The aim of the study was to assess adherence to HT in routine clinical practice in patients assisted at the Clinical Oncology Department of the Hospital de Clinicas - Universidad de la Republica, Uruguay.

METHODS

Patients treated with HT for stage 0-III BC between 2017 and 2019 were included. The medication possession (MPR) rate was calculated using pharmacy records, and the Morisky-Green Scale was applied to assess adherence. Adherent patients were those with MPR ≥ 0.80 and who correctly answered the Morisky-Green treatment adherence questionnaire. The association of adherence with polypharmacy, treatment, and patient characteristics was assessed using simple logistic models. The associations between qualitative variables and adherence were assessed using simple logistic regression model or Fisher's exact test. The association between quantitative variables and adherence was assessed using the Student's t-test. The odds ratio (OR) for non-adherence to treatment and its 95% confidence interval were estimated.

RESULTS

Totally, 118 patients were included; 65.2% were treated with aromatase inhibitors (AIs), 36.0% presenting polypharmacy. The adherence rate at the end of 2 years was 81.0 %; and it was associated with age (P = 0.03, OR = 0.96 for non-adherence), with adherent and non-adherent patients having a mean age of 65.0 and 60.3 years, respectively; however, adherence was not associated with polypharmacy, territory of origin, marital status, living alone, level of education, occupation, or stage. The adherence profile was similar for both drugs, but homemakers and retired women showed greater adherence to AI.

CONCLUSIONS

Adherence to HT was assessed in real life, with 19.0% of the patients not adhering to the treatment, despite the known benefit for OS, being a well-tolerated treatment, and being provided free of charge. Older patients were associated with being more adherent. The results show the need of the Pharmacy Service and Department of Clinical Oncology Medical Oncology combining efforts to develop coordinated strategies and interventions to increase adherence, given the impact that this may have on patients' OS.

Importance of endocrine treatment adherence and persistence in breast cancer survivorship: a systematic review

PURPOSE

Adjuvant endocrine treatment is essential for treating luminal subtypes of breast cancer, which constitute 75% of all breast malignancies. However, the detrimental side effects of treatment make it difficult for many patients to complete the guideline-required treatment. Such non-adherence may jeopardize the lifesaving ability of anti-estrogen therapy. In this systematic review, we aimed to assess the consequences of non-adherence and non-persistence from available studies meeting strict statistical and clinical criteria.

METHODS

A systematic literature search was performed using several databases, yielding identification of 2,026 studies. After strict selection, 14 studies were eligible for systematic review. The review included studies that examined endocrine treatment non-adherence (patients not taking treatment as prescribed) or non-persistence (patients stopping treatment prematurely), in terms of the effects on event-free survival or overall survival among women with non-metastatic breast cancer.

RESULTS

We identified 10 studies measuring the effects of endocrine treatment non-adherence and non-persistence on event-free survival. Of these studies, seven showed significantly poorer survival for the non-adherent or non-persistent patient groups, with hazard ratios (HRs) ranging from 1.39 (95% CI, 1.07 to 1.53) to 2.44 (95% CI, 1.89 to 3.14). We identified nine studies measuring the effects of endocrine treatment non-adherence and non-persistence on overall survival. Of these studies, seven demonstrated significantly reduced overall survival in the groups with non-adherence and non-persistence, with HRs ranging from 1.26 (95% CI, 1.11 to 1.43) to 2.18 (95% CI, 1.99 to 2.39).

CONCLUSION

The present systematic review demonstrates that non-adherence and non-persistence to endocrine treatment negatively affect event-free and overall survival. Improved follow-up, with focus on adherence and persistence, is vital for improving health outcomes among patients with non-metastatic breast cancer.

Breast Cancer Recurrence by Subtype in a Diverse, Contemporary Cohort of Young Women

BACKGROUND

Young breast cancer (YBC) patients are a unique subpopulation that are often underrepresented in randomized clinical trials. Furthermore, large national cancer databases lack detailed information on recurrence, a meaningful oncologic outcome for young patients.

STUDY DESIGN

A retrospective review of YBC patients (age 40 years or younger) with stage I to III breast cancer diagnosed from 2008 to 2018 was performed. Information on clinicopathologic characteristics, demographics, and outcomes was obtained from the electronic health record and chart review. Chi-square and Fisher's exact tests were used for comparisons of categorical variables and parametric and nonparametric tests for continuous variables.

RESULTS

The cohort included 1,431 women with a median follow-up of 4.8 years (range 0.3 to 12.9 years). The median age was 37 years (interquartile range 34 to 39). The study population included 598 (41.8%) White, 112 (7.8%) Black, 420 (29.4%) Asian/Pacific Islander, 281 (19.6%) Hispanic, and 20 (1.4%) "other" race/ethnicity patients. Tumor subtype was as follows: [1] hormone receptor (HR) + /human epidermal growth factor 2 (HER2 - ), grade (G) 1 to 2 = 541 (37.8%); [2] HR + /HER2 - , G3 = 268 (18.7%); [3] HR + /HER2 + = 262 (18.3%); [4] HR - /HER2 + = 101 (7.1%); [5] HR - /HER2 - = 259 (18.1%). The majority (64.2%) presented with stage II/III disease. There were 230 (16.1%) recurrences during follow-up; 74.8% were distant. Locoregional-only recurrence was seen in 17 of 463 (3.7%) patients who underwent breast conservation vs 41 of 968 (4.2%) patients undergoing mastectomy (p < 0.001). Recurrence varied by tumor subtype: [1] HR + /HER2 - , G1 to 2 (14.0%); [2] HR + /HER2 - , G3 (20.9%); [3] HR + /HER2 + (11.1%); [4] HR - /HER2 + (22.8%); [5] HR - /HER2 - (17.8%) (p = 0.005).

CONCLUSIONS

In this large, diverse YBC cohort, recurrences were most frequent among HR + /HER2 - , G3, or HR - /HER2 + invasive tumors; most were distant. There were numerically similar locoregional-only recurrences after breast conservation vs mastectomy. Additional research is needed to identify predictors of recurrence.

Abemaciclib in Combination with Endocrine Therapy for Adjuvant Treatment of Hormone Receptor-Positive, HER2-Negative, Node-Positive Early Breast Cancer: An Evidence Review Group Perspective of a NICE Single Technology Appraisal

The National Institute for Health and Care Excellence (NICE) invited the manufacturer (Eli Lilly) of abemaciclib (Verzenios) to submit evidence for the clinical and cost effectiveness of this drug in combination with endocrine therapy (ET) for the treatment of adult patients with hormone receptor (HR)-positive, human epidermal growth factor receptor 2 (HER2)-negative, node-positive early breast cancer at high risk of recurrence, as part of the Institute's Single Technology Appraisal (STA) process. Kleijnen Systematic Reviews Ltd, in combination with Newcastle University, was commissioned to act as the independent Evidence Review Group (ERG). This paper summarised the Company Submission (CS), presents the ERG's critical review of the clinical and cost-effectiveness evidence in the CS, highlights the key methodological considerations, and describes the development of the NICE guidance by the Appraisal Committee. The ERG produced a critical review of the evidence for the clinical and cost-effectiveness evidence in the CS and also independently searched for relevant evidence and modified the manufacturer decision analytic model to examine the impact of altering some of the key assumptions. A systematic literature review identified the MonarchE trial, an ongoing, open-label, randomised, double blind trial involving 5637 people comparing abemaciclib in combination with ET versus ET alone. The trial included two cohorts that used different inclusion criteria to define high risk of recurrence. The ERG considered Cohort 1 as an adequate representation of this population and the AC concluded that Cohort 1 was generalisable to National Health Service clinical practice. Trial results showed improvements in invasive disease-free survival for the abemaciclib arm, which was considered an appropriate surrogate outcome. The ERG believed that the modelling structure presented in the de novo economic model by the company was appropriate but highlighted several areas of uncertainty that had the potential to have a significant impact on the resulting incremental cost-effectiveness ratio (ICER). Areas of uncertainty included the extrapolation of long-term survival curves, the duration of treatment effect and treatment waning, and the proportion of patients who receive other CDK4/6 treatments for metastatic disease after receiving abemaciclib. ICER estimates were £9164 per quality-adjusted life-year gained for the company's base-case and £17,810 for the ERG's base-case. NICE recommended abemaciclib with ET as an option for the adjuvant treatment of HR-positive, HER2-negative, node-positive early breast cancer at high risk of recurrence.

Preoperative Partial Breast Irradiation in Patients with Low-Risk Breast Cancer: A Systematic Review of Literature

BACKGROUND

Preoperative instead of standard postoperative partial breast irradiation (PBI) after breast-conserving surgery (BCS) has the advantage of reducing the irradiated breast volume, toxicity, and number of radiotherapy sessions and can allow tumor downstaging. In this review, we assessed tumor response and clinical outcomes after preoperative PBI.

PATIENTS AND METHODS

We conducted a systematic review of studies on preoperative PBI in patients with low-risk breast cancer using the databases Ovid Medline, Embase.com, Web of Science (Core Collection), and Scopus (PROSPERO registration CRD42022301435). References of eligible manuscripts were checked for other relevant manuscripts. The primary outcome measure was pathologic complete response (pCR).

RESULTS

A total of eight prospective and one retrospective cohort study were identified (n = 359). In up to 42% of the patients, pCR was obtained and this increased after a longer interval between radiotherapy and BCS (0.5-8 months). After a maximum median follow-up of 5.0 years, three studies on external beam radiotherapy reported low local recurrence rates (0-3%) and overall survival of 97-100%. Acute toxicity consisted mainly of grade 1 skin toxicity (0-34%) and seroma (0-31%). Late toxicity was predominantly fibrosis grade 1 (46-100%) and grade 2 (10-11%). Cosmetic outcome was good to excellent in 78-100% of the patients.

CONCLUSIONS

Preoperative PBI showed a higher pCR rate after a longer interval between radiotherapy and BCS. Mild late toxicity and good oncological and cosmetic outcomes were reported. In the ongoing ABLATIVE-2 trial, BCS is performed at a longer interval of 12 months after preoperative PBI aiming to achieve a higher pCR rate.

Medication Adherence among Allogeneic Haematopoietic Stem Cell Transplant Recipients: A Systematic Review

Recipients of a haematopoietic stem cell transplantation (HSCT) may experience issues in medication adherence (MA) when discharged. The primary aim of this review was to describe the oral MA prevalence and the tools used to evaluate it among these patients; the secondary aims were to summarise factors affecting medication non-adherence (MNA), interventions promoting MA, and outcomes of MNA. A systematic review (PROSPERO no. CRD42022315298) was performed by searching the Cumulative Index of Nursing and Allied Health (CINAHL), Cochrane Library, Excerpta Medica dataBASE (EMBASE), PsycINFO, PubMed and Scopus databases, and grey literature up to May 2022 by including (a) adult recipients of allogeneic HSCT, taking oral medications up to 4 years after HSCT; (b) primary studies published in any year and written in any language; (c) with an experimental, quasi-experimental, observational, correlational, and cross-sectional design; and (d) with a low risk of bias. We provide a qualitative narrative synthesis of the extracted data. We included 14 studies with 1049 patients. The median prevalence of MA was 61.8% and it has not decreased over time (immunosuppressors 61.5% [range 31.3-88.8%] and non-immunosuppressors 65.2% [range 48-100%]). Subjective measures of MA have been used most frequently (78.6%) to date. Factors affecting MNA are younger age, higher psychosocial risk, distress, daily immunosuppressors, decreased concomitant therapies, and experiencing more side effects. Four studies reported findings about interventions, all led by pharmacists, with positive effects on MA. Two studies showed an association between MNA and chronic graft-versus-host disease. The variability in adherence rates suggests that the issues are relevant and should be carefully considered in daily practice. MNA has a multifactorial nature and thus requires multidisciplinary care models.

SRSF5 Regulates the Expression of BQ323636.1 to Modulate Tamoxifen Resistance in ER-Positive Breast Cancer

About 70% of breast cancer patients are oestrogen receptor-positive (ER +ve). Adjuvant endocrine therapy using tamoxifen (TAM) is an effective approach for preventing local recurrence and metastasis. However, around half of the patients will eventually develop resistance. Overexpression of BQ323636.1 (BQ) is one of the mechanisms that confer TAM resistance. BQ is an alternative splice variant of NCOR2. The inclusion of exon 11 generates mRNA for NCOR2, while the exclusion of exon 11 produces mRNA for BQ. The expression of SRSF5 is low in TAM-resistant breast cancer cells. Modulation of SRSF5 can affect the alternative splicing of NCOR2 to produce BQ. In vitro and in vivo studies confirmed that the knockdown of SRSF5 enhanced BQ expression, and conferred TAM resistance; in contrast, SRSF5 overexpression reduced BQ expression and, thus, reversed TAM resistance. Clinical investigation using a tissue microarray confirmed the inverse correlation of SRSF5 and BQ. Low SRSF5 expression was associated with TAM resistance, local recurrence and metastasis. Survival analyses showed that low SRSF5 expression was associated with poorer prognosis. We showed that SRPK1 can interact with SRSF5 to phosphorylate it. Inhibition of SRPK1 by a small inhibitor, SRPKIN-1, suppressed the phosphorylation of SRSF5. This enhanced the proportion of SRSF5 interacting with exon 11 of NCOR2, reducing the production of BQ mRNA. As expected, SRPKIN-1 reduced TAM resistance. Our study confirms that SRSF5 is essential for BQ expression. Modulating the activity of SRSF5 in ER +ve breast cancer will be a potential approach to combating TAM resistance.

Adherence to endocrine therapy in early breast cancer in relation to Cytochrome P450 2D6 genotype: a comparison between pharmacy dispensation data and medical records

PURPOSE

Suboptimal adherence to adjuvant endocrine treatment (AET) is an important clinical concern. A correlation between CYP2D6 activity and tamoxifen discontinuation has been described. The main aim of this study was to investigate the consistency between pharmacy dispensation data and medical records on adherence to AET.

METHODS

Adherence was calculated for patients with at least 4.5 years of follow up and was defined as Medical Possession Rate ≥ 80%. Subgroup analyses were performed based on menopausal status, recurrence risk and CYP2D6 activity.

RESULTS

In 86% of the 1235 included patients the consistency between the two sources of information was within 80-125%. Poor consistency, < 80%, was most frequent in the premenopausal/ high-risk group and CYP2D6 Poor Metabolizers (PMs). Among 899 patients with at least 4.5 years follow up, 72% were adherent to tamoxifen based on pharmacy dispensation data, compared with 77% as reported by medical records. When including patients who switched to aromatase inhibitors after tamoxifen, adherence increased to 82% and 88%, respectively. Adherence did not differ by menopausal status or risk for recurrence. CYP2D6 PMs had poorer adherence (54%) to tamoxifen compared to patients with the highest CYP2D6 activity (83%).

CONCLUSIONS

There was a good consistency between medical records and pharmacy dispensing data on the use of AET. Adherence to AET was adequate, especially when including switch to aromatase inhibitors. Surprisingly, CYP2D6 PMs had low adherence to tamoxifen, despite a likely reduced risk of side effects according to previous data.

Adherence to oral anticancer hormonal therapy in breast cancer patients and its relationship with treatment satisfaction: an important insight from a developing country

BACKGROUND

Hormone-positive breast cancer is the most common type and represents a burden in all countries. Treatment satisfaction might be a predictor for adherence, as higher satisfaction with medication encourages patients to adhere appropriately to the medication and, consequently, successfully achieve the treatment goals. The present study evaluated the adherence of women with hormone-positive breast cancer to oral hormonal drugs and correlated it with treatment satisfaction and other sociodemographic and clinical factors.

METHODS

A cross-sectional design was applied. This study included two cancer centers. Data were collected from patients through face-to-face interviews and medical record reviews. The Medication Adherence Scale was adapted to assess medication adherence, and the Treatment Satisfaction Questionnaire for Medication (TSQM) version 1.4 was adopted to measure treatment satisfaction.

RESULTS

The final analysis included 106 patients, with a mean age ± SD of 51.9 ± 1.2. Approximately 35% were hospitalized in the past year. Current hormonal therapy among cancer patients included letrozole (38.7%), tamoxifen (31.1%), exemestane (17%), and anastrozole (13.2%). The median adherence score was 5.0 [4.8-6.0], and 62.3% adhered fully to their oral hormonal drugs in the past week. The median scores of effectiveness, side effects, convenience, and global satisfaction were 66.67 [61.11.0-72.22], 75.00 [48.44-100.00], 66.67 [66.67-72.22], and 71.43 [57.14-78.57], respectively. A significantly lower adherence score was identified in patients living in camps (p = 0.020). Patients with comorbidities and those who continued on the same hormonal therapy had higher adherence scores, although they were not statistically significant. Multiple linear regression analysis showed that two domains of treatment satisfaction, side effects (p = 0.013) and global satisfaction (p = 0.018), were predictors of adherence to oral hormonal drugs.

CONCLUSIONS

The current study revealed a significant association between treatment satisfaction and adherence to oral hormonal therapy. We recommend creating a specialized scale to measure adherence, considering the psychosocial factors that affect hormonal anticancer medication adherence.

Menopausal symptoms in breast cancer patients receiving adjuvant endocrine therapy and their relationships with health-promoting behaviors and social support

OBJECTIVE

To investigate the prevalence and severity of menopausal symptoms in patients with breast cancer undergoing adjuvant endocrine therapy and explore the relationships of these symptoms with health-promoting behaviors and social support.

METHODS

This cross-sectional study investigated 226 participants from December 2020 to December 2021 in China. Data were collected using the sociodemographic information questionnaire, Menopause Rating Scale, the Health-Promoting Lifestyle Profile II, and Perceived Social Support Survey. Multivariate step regression was used to analyze the potential factors of menopausal symptoms.

RESULTS

In our sample of 226 patients, 92.9% reported at least one menopausal symptom with a mean score of 13 points (interquartile range, 9-18 points). The highest prevalence of most symptoms included hot flashes/night sweats, fatigue, joint and muscular discomfort, irritability, and sleep problems. In the regression models, health responsibility ( β = -0.15, P = 0.03), spiritual growth ( β = -0.28, P < 0.01), friend support ( β = -0.43, P < 0.01), and other support ( β = -0.31, P = 0.01) were negatively associated with menopausal symptoms.

CONCLUSIONS

The prevalence and severity of menopausal symptoms are high in breast cancer patients undergoing adjuvant endocrine therapy. Higher health-promoting behaviors and social support are associated with fewer menopausal symptoms. The findings highlight the clinical implications in terms of developing appropriate strategies for managing menopausal symptoms.

Adherence to oral hormonal therapy in advanced prostate cancer: a scoping review

Background:

Orally administrated agents play a key role in the management of prostate cancer, providing a convenient and cost-effective treatment option for patients. However, they are also associated with adherence issues which can compromise therapeutic outcomes. This scoping review identifies and summarizes data on adherence to oral hormonal therapy in advanced prostate cancer and discusses associated factors and strategies for improving adherence.

Methods:

PubMed (inception to 27 January 2022) and conference databases (2020–2021) were searched to identify English language reports of real-world and clinical trial data on adherence to oral hormonal therapy in prostate cancer using the key search terms ‘prostate cancer’ AND ‘adherence’ AND ‘oral therapy’ OR respective aliases.

Results:

Most adherence outcome data were based on the use of androgen receptor pathway inhibitors in metastatic castration-resistant prostate cancer (mCRPC). Self-reported and observer-reported adherence data were used. The most common observer-reported measure, medication possession ratio, showed that the vast majority of patients were in possession of their medication, although proportion of days covered and persistence rates were considerably lower, raising the question whether patients were consistently receiving their treatment. Study follow-up for adherence was generally around 6 months up to 1 year. Studies also indicate that persistence may drop further with longer follow-up, especially in the non-mCRPC setting, which may be a concern when years of therapy are required.

Conclusions:

Oral hormonal therapy plays an important role in the treatment of advanced prostate cancer. Data on adherence to oral hormonal therapies in prostate cancer were generally of low quality, with high heterogeneity and inconsistent reporting across studies. Short study follow-up for adherence and focus on medication possession rates may further limit relevance of available data, especially in settings that require long-term treatment. Additional research is required to comprehensively assess adherence.

5-year adherence to adjuvant endocrine treatment in Dutch women with early stage breast cancer: A population-based database study (2006-2016)

BACKGROUND

Hormonal receptor (HR) positive breast tumors are common. Adjuvant hormonal therapy (AHT) with tamoxifen or Aromatase Inhibitors (AIs) is beneficial depending on the stage of the tumor. Despite the fact that AHT has been shown to improve survival and recurrence, Dutch adherence rates, which were mostly dependent on Tamoxifen prescriptions until 2006, plummeted from 80% after one year to 50% after five years. Nonadherence with AHT reduces its effectiveness. This research presents more recent adherence statistics (from 2006 to 2016), on a larger sample (7,996 vs 1,451), as well as factors that influence AHT adherence. In addition to tamoxifen data, AIs are now included.

OBJECTIVE

As low use of adjuvant endocrine therapy is a potentially important and modifiable risk factor for poor outcome, it is important to monitor the rate as an indicator of women's burden of disease and the direction of adherence trends.

METHODS

The Netherlands Cancer Registry (NCR) was used to find women with early-stage breast cancer who started AHT within a year of surgery and were linked to the PHARMO Database Network (n = 8,679). The Kaplan-Meier approach was used to measure AHT adherence five years after treatment was started, with a 60-day gap between refills as our primary outcome. Furthermore, the Medication Possession Rate (MPR) was determined using a cutoff of ≥80%. Analysis was performed on influential factors of adherence.

RESULTS

The proportion of persistent women declined over time to reach 46.6% at the end of the fifth year and 53.3% of the women had a MPR ≥80% during the fifth year. Older and being diagnosed in 2006-2010 were associated with AHT adherence.

CONCLUSION

Dutch 5-year AHT adherence appears to remain poor. Improving AHT adherence in HR+ breast cancer survivors is a critical medical need.

Adherence to Oral Anticancer Medications Among Women With Breast Cancer in Africa: A Scoping Review

PURPOSE

Oral anticancer medications (OAMs) improve treatment outcomes and survival in women with breast cancer (BC). However, adherence to OAM therapy remains suboptimal. This scoping review provides evidence of adherence to OAMs among African women with BC.

METHODS

We searched four databases and gray literature, using guidance from the Joanna Briggs Institute. Thirteen studies on adherence rates, determinants, and interventions were included. NVivo 12 software was used to perform thematic analysis of the included studies. The determinants (barriers and facilitators) associated with adherence were analyzed according to the five dimensions of the WHO multidimensional adherence model.

RESULTS

Most studies (n = 11, 85%) focused on endocrine medication. Depending on the definition, measurements, and assessment period, the nonadherence rates ranged from 4.3% to 65.4% for endocrine medications, 80.9% for cytotoxic chemotherapies, and 32.7% for combined medications. The significant barriers associated with adherence include Islamic religion, concurrent comorbidities, mastectomy, anastrozole treatment, side effects, unawareness of treatment insurance coverage, and seeking treatment from traditional healers. Thorough therapeutic communication regarding treatment, neoadjuvant chemotherapy, and adequate social support significantly facilitate adherence. A randomized controlled trial of breast nursing interventions reported improved patient adherence.

CONCLUSION

The evidence mapped from studies that evaluated OAM adherence in women with BC indicates that nonadherence to OAMs is common. Applying context-specific standardized measures to assess adherence and facilitators or strategies targeting the identified barriers can optimize adherence and treatment outcomes. Effective interventions to improve adherence are limited. Therefore, further empirical and interventional studies in Africa are required to enhance the evidence.

Cost-Effectiveness Analysis of Ultra-Hypofractionated Whole Breast Radiation Therapy Alone Versus Hormone Therapy Alone or Combined Treatment for Low-Risk ER-Positive Early Stage Breast Cancer in Women Aged 65 Years and Older

PURPOSE

The optimal management of early-stage, low-risk, hormone-positive breast cancer in older women remains controversial. Recent trials have shown that 5-fraction ultrahypofractionated whole-breast irradiation (U-WBI) has similar outcomes to longer courses, reducing the cost and inconvenience of treatment. We performed a cost-utility analysis to compare U-WBI to hormone therapy alone or their combination.

METHODS AND MATERIALS

We simulated 3 different treatment approaches for women age 65 years or older with pT1-2N0 ER-positive invasive ductal carcinoma treated with lumpectomy with negative margins using a Markov microsimulation model. The strategies were U-WBI performed with a 3-dimensional conformal technique over 5 fractions without a boost ("radiation therapy [RT] alone"), adjuvant hormone therapy (anastrozole for 5 years) without RT ("aromatase-inhibitor [AI] alone"), or the combination of the 2. The combination strategy was calibrated to match trial results, and the relative effectiveness of the RT alone and AI alone strategies were inferred from previous randomized trials. The primary endpoint was the cost-effectiveness of the 3 strategies over a lifetime horizon as measured by the incremental cost-effectiveness ratio (ICER), with a value of $100,000/quality-adjusted life-year deemed "cost-effective."

RESULTS

The model results compared with the prespecified target outcomes. On average, RT alone was the least expensive strategy ($14,775), with AI alone slightly more ($14,998), and combination therapy the costliest ($19,802). RT alone dominated AI alone (the incremental cost-effectiveness ratio [ICER] -$5089). Combination therapy, compared with RT alone, was slightly more expensive than our definition of cost-effective (ICER $113,468) but was cost-effective compared with AI alone (ICER $54,451). Probabilistic sensitivity analysis demonstrated RT alone to be cost-effective in 50% of trials, with combination therapy in 36% and AI alone in 14%.

CONCLUSIONS

U-WBI alone appears the more cost-effective de-escalation strategy for these low-risk patients, compared with AI alone. Combining U-WBI and AI appears more costly but may be preferred by some patients.

Optimizing Adjuvant Treatment Recommendations for Older Women with Biologically Favorable Breast Cancer: Short-Course Radiation or Long-Course Endocrine Therapy?

Omission of radiotherapy among older women taking 5 years of adjuvant endocrine therapy following breast conserving surgery for early-stage, hormone sensitive breast cancers is well-studied. However, endocrine therapy toxicities are significant, and many women have difficulty tolerating endocrine therapy, particularly elderly patients with comorbidities. Omission of endocrine therapy among women receiving adjuvant radiation is less well-studied, but available randomized and non-randomized data suggest that this approach may confer equivalent local control and survival for select patients. Herein we review available randomized and non-randomized outcome data for women treated with radiation monotherapy and emphasize the need for future prospective, randomized studies of endocrine therapy omission.

Identifying the predictors of adherence to oral endocrine therapy in racial/ethnic minority patients with low socioeconomic status

Background Adherence to oral endocrine therapy (OET) is crucial in ensuring its maximum benefit in prevention and treatment of hormone receptor-positive (HR+) breast cancer (BC) in patients. Medication use behavior is suboptimal especially in racial/ethnic minorities of lower socioeconomic status (SES). We aimed to assess the OET adherence and its predictors in racial/ethnic minority patients of lower SES. Aim We aimed to assess the OET adherence and determine the predictors of OET nonadherence in racial/ethnic minority patients of lower SES. Method A retrospective study was conducted at the Harris Health System in Houston, Texas. Since the study period included the COVID-19 pandemic, data was collected during the 6 months prior and 6 months after the start of the pandemic. The adherence was assessed using the prescription refill data using the proportion of days covered. Multivariable logistic regression model was used to identify predictors of nonadherence. Eighteen years or older patients on appropriate doses of OET for prevention or treatment of BC were included. Result In 258 patients, the adherence was significantly lower during the pandemic (44%) compared to before the pandemic (57%). The predictors of OET nonadherence before the pandemic were Black/African American, obesity/extreme obesity, prevention setting, tamoxifen therapy, and 4 or more years on OET. During the pandemic, prevention setting and those not using home delivery were more likely to be nonadherent. Conclusion Racial/ethnic minority patients of lower SES, especially African Americans and those using OET for prevention of BC, require individualized interventions to improve adherence.

The relationship between medication adherence and illness perception in breast cancer patients with adjuvant endocrine therapy: beliefs about medicines as mediators

PURPOSE

To describe medication adherence, to analyze the relationships among medication adherence, illness perception, and beliefs about medicines, and to determine the mediating effects of beliefs about medicines on the relationship in breast cancer patients with adjuvant endocrine therapy (AET) in China.

METHODS

A cross-sectional study was conducted on 202 breast cancer patients with AET from September 2017 to February 2019 in China. The Medication Adherence Report Scale (MARS-5), the Chinese version of the revised illness perception questionnaire for Breast Cancer (CIPQ-R-BC) and the Beliefs about Medicines Questionnaire (BMQ) were used.

RESULTS

The mean MARS-5 score of our participants was 23.72 (SD = 1.62), and 175 (86.6%) patients were adherent to medications. Moreover, medication adherence was negatively correlated with identity, environmental or immune factors, emotional representations, BMQ-specific concerns, BMQ-general overuse, and BMQ-general harm, as well as being positively correlated with coherence and the total BMQ scores. Furthermore, beliefs in the overuse about medicines functioned as mediators for the influencing effects of coherence and emotional representations on medication adherence.

CONCLUSION

Illness perception not only directly affected medication adherence, but also indirectly affected medication adherence through the beliefs about medicines. Necessary interventions that target beliefs in the overuse about medicines in breast cancer patients with AET with low levels of coherence or high levels of emotional representations could be provided to improve the level of their medication adherence.

Association of Adherence to Endocrine Therapy Among Patients With Breast Cancer and Potential Drug-Drug Interactions

IMPORTANCE

Suboptimal adherence to endocrine therapy (ET) among patients with hormone-receptor-positive breast cancer significantly affects survival outcomes and is associated with higher hospitalization rates and health care costs. Weak adherence to long-term treatments has multiple determinants, including disease characteristics, treatment adverse effects, and patients' attributes, such as age and comorbidities.

OBJECTIVE

To examine whether potential drug-drug interactions (PDDI) with tamoxifen or aromatase inhibitor were associated with adherence to ET in patients with early and advanced breast cancer.

DESIGN, SETTING, AND PARTICIPANTS

This cohort study used anonymized health record data of women with breast cancer who received ET in a private observational primary care database. Patients eligible for analysis included women aged 18 years or older who had a reported diagnosis of breast cancer and received ET with tamoxifen or aromatase inhibitor between 1994 and 2021. Data were analyzed 2021.

EXPOSURES

Adherence to ET during a given year was defined by a medication possession ratio of 80% or greater over 1-year prescription periods. PDDI were categorized into absent, minor (a combination to take into account), moderate (combination requiring precautions for use), major (combination not recommended), and contraindicated according to guidelines in the Claude Bernard Drug Database.

MAIN OUTCOMES AND MEASURES

We used regression models to estimate odds ratios (ORs) and 95% CIs for the associations between adherence and age, baseline comorbidities, PDDI, and adherence to ET during the previous year.

RESULTS

A total of 10 863 patients who were prescribed ET for breast cancer were eligible for the analysis (age 70 years or older, 3509 patients [32.3%]). In the tamoxifen cohort (3564 patients), PDDI were reported in 497 of 3670 patients (13.5%) at baseline (moderate, 254 patients [51.1%]; major, 227 patients [45.7%]), 2047 of 4831 patients (42.4%) at year 1, 1127 of 2751 patients (41.0%) at year 2, 761 of 1861 patients (40.9%) at year 3, 376 of 1058 patients (35.5%) at year 4, and 201 of 593 patients (33.9%) at year 5. In the aromatase inhibitor cohort (7299 patients), PDDI were reported in 592 of 7437 patients (8.0%) at baseline (moderate in 588 of 592 patients [99.3%]), which reached 2875 of 9031 patients (31.8%) at year 1 and ranged between 31.4% (1802 of 5730 patients in year 2) and 32.8% (791 of 2411 in year 4) throughout the study period. No association between adherence and PDDI was found in the tamoxifen (OR, 0.99; 95% CI, 0.91-1.08) or aromatase inhibitor (OR, 1.05; 95% CI, 0.95-1.15) cohort.

CONCLUSIONS AND RELEVANCE

In this cohort of patients with hormone-receptor-positive breast cancer, PDDI with tamoxifen and aromatase inhibitors were not associated with adherence to ET.