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

A Dedicated Menopausal After Cancer Clinic May Improve Adherence to Endocrine Therapy For Breast Cancer: A Population Based Study

PURPOSE

To examine utilization of a dedicated menopause symptoms after cancer clinic (MSAC) and to determine whether women referred to the MSAC for management of severe hot flush symptoms are more likely to adhere to endocrine therapy compare to those with severe symptoms not referred to MSAC.

PATIENTS AND METHODS

Breast cancer patients prescribed endocrine therapy with a diagnosis of estrogen-receptor positive breast cancer between January 2003 and December 2011 were identified from the Royal Perth Hospital Breast Unit database. Details of breast cancer pathology, endocrine therapy, endocrine therapy related side effects, referral to MSAC and patient reported adherence to endocrine therapy for up to 4 years were ascertained from the database and medical records systems. For those with severe vasomotor symptoms, total duration of endocrine therapy was compared between women referred to MSAC and those who were not referred to MSAC.

RESULTS

About 1275 women were identified from the database, with the cohort followed up until Dec 2016. Of these women, 120 (9.4%) were referred to MSAC and 1155 (90.1%) received usual care. In total, 147 reported severe vasomotor symptoms of whom almost half (71) were referred to MSAC. Women with severe vasomotor symptoms managed by MSAC were less likely to discontinue endocrine therapy (15.5%) compared with those managed with usual care (26.3%). However, this difference was not statistically significant (chi-square test statistic = 2.584, 1df, P = .1).

CONCLUSION

Management of severe vasomotor symptoms at a dedicated menopause clinic may increase adherence to endocrine therapy for breast cancer.

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

PURPOSESocial characteristics, including cohabitation/marital status and socioeconomic position (SEP)-education level, employment status, and income-influence breast cancer prognosis. We investigated the impact of these social characteristics on adherence to adjuvant endocrine therapy (AET) from treatment initiation to 5 years after diagnosis.METHODSWe assembled a nationwide, population-based cohort of premenopausal women diagnosed in Denmark with stage I-III, estrogen receptor-positive breast cancer during 2002-2011. We ascertained prediagnostic social characteristics from national registries. AET adherence was based on information from the Danish Breast Cancer Group and operationalized as (1) adherence trajectories (from group-based trajectory modeling) and (2) early discontinuation. We computed odds ratios (ORs) and associated 95% CI to estimate the association of cohabitation and SEP with AET adherence using multinomial and logistic regression models adjusted according to directed acyclic graphs.RESULTSAmong 4,353 patients, we identified three adherence trajectories-high adherence (57%), slow decline (36%), and rapid decline (6.9%). Compared with cohabiting women, those living alone had higher ORs of slow (1.26 [95% CI, 1.08 to 1.46]) or rapid decline (1.66 [95% CI, 1.27 to 2.18]) versus high adherence. The corresponding ORs for women not working versus employed women were 1.22 (95% CI, 1.02 to 1.45) and 1.76 (95% CI, 1.30 to 2.38). For early discontinuation (17%), the ORs were 1.48 (95% CI, 1.23 to 1.78) for living alone and 1.44 (95% CI, 1.17 to 1.78) for women not working.CONCLUSIONAdherence to AET was lower among women living alone or unemployed than cohabiting or employed women, respectively. These women may benefit from support programs to enhance AET adherence.

Clinical management of oligometastatic cancer: Applying multidisciplinary tumor board recommendations in practice

Aims

Multidisciplinary tumor boards (MDTs) are an integral part of ensuring high-quality, evidence-based and personalized cancer care. In this study, we aimed to evaluate the adherence to and implementation of MDT recommendations in patients with oligometastatic disease (OMD).

Methods

We screened all oncologic positron emission tomography (PET) scans conducted at a single comprehensive cancer center in 2020. Patients were included if they had evidence of imaging-based OMD from a solid organ malignancy on the index scans, had their OMD case discussed at an MDT, and were treated and followed up at the same center. A switch away from the MDT-recommended treatment modalities was classified as a major deviation; non-MDT-mandated adjustments to a recommended treatment modality were coded as minor deviation. Clinical data was obtained via chart review; statistical calculations were computed using the R software.

Results

After review of PET and/or concurrent brain scans, 787 cases of OMD were identified. Thereof, 347 (44.1 %) cases were discussed at MDT, of which 331 (42.1 %) were therapeutically managed and subsequently followed. The three most commonly recommended therapies were systemic therapy (35.6 %), multimodality treatment including definitive local therapy (17.8 %), and radiotherapy (13.9 %). A major deviation was recorded in 16.3 % of cases (most commonly: none of the MDT-recommended treatment modalities were performed: 19 (35.2 %); not all MDT-planned treatment modalities were performed: 12 (22.2 %); and additional treatment modality was performed: 11 (20.3 %). A minor deviation was found in 1.5 % of cases. On multivariable regression, number of distant metastases (n > 1) was associated with a major deviation (OR: 1.85; 95 % CI, 1.0-3.52). Major deviations were associated with a significantly worse OS (p = 0.0034).

Conclusions

Adherence to and implementation of MDT recommendations in OMD patients was generally high (83.7%). Major deviations might be further reduced by more careful and elaborate discussions of OMD patient characteristics s and patient preferences.

Breast cancer survivors' opinion on personalizing endocrine therapy and developing informative tools

Understanding breast cancer survivors' perspectives is critical to personalizing endocrine therapy (ET) in the adjuvant setting. A nationwide survey among breast cancer survivors was proposed in France, in collaboration with patient advocacy organizations, to assess their perspectives on personalizing ET and developing dedicated informative tools. This survey explored patients' preferences regarding ET intake schedule, formulation, presentation (color, taste, shape, size, design, and packaging), combination with agents targeting ET-related adverse events, and a mobile application to support them during ET. Of the 1103 individuals who started the survey, 939 (85.1%) were eligible for enrollment and completed the survey. The majority of the participants considered that a personalized ET should take into consideration the intake schedule (n = 974, 90.7%) and swallowable tablet formulation (n = 606, 64.5%), without a preference for ET presentation (n = 619; 65.9%). The majority of the participants expressed a willingness to participate in a potential clinical trial evaluating the combination of ET with agents targeting ET-related adverse events at the start of ET (n = 752, 80.1%) or in the case of major ET-related adverse events (n = 778, 82.8%). The primary considerations were to have an uncompromised ET efficacy and a guaranteed reduction of adverse events. Last, a dedicated mobile application was considered helpful by 665 participants (70.8%). Informative tools should focus on the recommendations for dealing with adverse events (n = 593, 63.2%), the impact on the patient's daily life (n = 515, 54.9%), benefits (n = 504, 53.7%), and adverse events (n = 494, 52.6%) of ET. This survey paves the way for multimodal strategies that can include a personalized ET (e.g., ET in combination with agents targeting ET-related adverse events) and dedicated mobile applications to ultimately improve adherence.

Follow-up Routines Matter for Adherence to Endocrine Therapy in the Adjuvant Setting of Breast Cancer

Background

Endocrine therapy (ET) adherence leads to increased survival in breast cancer (BC). How follow-up should be done to maximize adherence is not known.

Objectives

To assess adherence to ET, factors favouring adherence to ET and effects on survival in a population-based cohort of BC patients in western Sweden.

Design

This is a retrospective study.

Methods

We included 358 patients operated for oestrogen receptor-positive BC and recommended 5 years of ET, in Region Halland, Sweden, year 2015 to 2016. Demographical, clinical and pathological data and use of ET were retrieved from the electronic medical records. Patients were considered adherent if taking ET for 5 years or during the full extent of the follow-up, until termination of ET due to BC relapse or death and where renewals of prescriptions of ET covered ⩾80% of the ordinated dose. Two follow-up routines were employed, ie, routine A where patients were contacted annually by nurses and a more passive follow-up routine B where patients were only contacted by nurses at 2 years and 5 years following start of ET.

Results

Medication persistence for 4 years and more was good and similar between patients initiating aromatase inhibitor (AI) and tamoxifen (75.7% and 72.0%, respectively, P = .43). More patients initiating AIs changed ET due to side effects compared with patients initiating tamoxifen (24.3% vs 9.9%, respectively, P < .0001). Endocrine therapy adherence was better for follow-up routine B than for follow-up routine A (hazard ratio [HR] = 2.71 [1.44-5.09], P = .0027).

Conclusions

Adherence to ET in BC is high in Western Sweden. Less regular nurse-initiated contacts between BC patients and nursesled surprisingly to a better adherence than a more regular nurse-initiated contact.

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.

Information Support Provided by Specialized Nurses via Mobile Healthcare App May Improve Treatment Adherence of Breast Cancer Patients: An Observational Study

OBJECTIVES

Mobile devices facilitate the healthcare management of breast cancer. Meanwhile, specialist nurses play an important role in disease management. We established a smartphone-based app that enables patients to raise questions to specialist nurses. We aimed to evaluate whether the information support provided by specialist nurses via smartphone app could improve the treatment adherence of breast cancer patients.

DATA SOURCE

Breast cancer patients who received surgery and registered for the app between March 2013 and April 2020 were included. Data related to the use of the app, the number of raised questions, and the specific content of each question were retrieved. Overall, 2675 patients were included, with 560 patients raising questions to specialist nurses via the app. Patients with higher educational levels, postmenopause status, and more advanced diseases were more likely to seek informational support via a smartphone app. The treatment adherence was 86.4%. Multivariate analysis demonstrated that raising questions was associated with better compliance. Regarding the distribution of questions, 78.8% of patients had questions about the treatment schedule and procedure, 65.9% of patients had questions during the adjuvant treatment, and only 19.6% of patients raised questions about follow-up and rehabilitation. After a median follow-up of 44 months, there was no survival difference between patients who raised questions and those who did not.

CONCLUSION

Seeking information support from specialist nurses was associated with better treatment adherence. The smartphone-based healthcare app enables specialist nurses to provide more conducive service for patients, and validation of this finding in further studies is warranted.

IMPLICATIONS FOR NURSING PRACTICE

Breast cancer patients were more interested in problems with treatment procedures and schedules. Those who asked questions had better treatment adherence. The smartphone-based app could not only provide patients with a platform to seek information support but also help specialist nurses understand the needs of patients.

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.

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.

Feasibility of Symptom Monitoring During the First Year of Endocrine Therapy for Early Breast Cancer Using Patient-Reported Outcomes Collected via Smartphone App

PURPOSE

Treatment-associated symptoms drive early discontinuation of adjuvant endocrine therapy (ET) for breast cancer. We hypothesized that symptom monitoring with electronic patient-reported outcomes (ePROs) during adjuvant ET will enhance symptom detection, symptom management, and persistence.

METHODS

Eligible patients were initiating ET for stage 0-III breast cancer. Participants completed ePRO surveys via smartphone at baseline and 1, 3, 6, and 12 months. Measures included Patient-Reported Outcomes Measurement Information System Anxiety, Depression, Fatigue, and Vaginal Discomfort; plus Patient-Reported Outcomes version of the Common Terminology Criteria for Adverse Events items assessing joint pain, hot flashes, vaginal dryness, concentration problems, and memory problems. Scores surpassing prespecified thresholds triggered alerts, and recommended symptom management pathways were provided to clinicians. The primary objective was to evaluate feasibility, assessed by survey completion rates, with targets of >65% for the baseline survey and ≥1 follow-up survey during the first 6 months. Secondary objectives included 12-month ET discontinuation rate (target: ≤15%), describing symptoms and evaluating pathway implementation.

RESULTS

Among 250 participants, 73.2% completed the baseline survey and 69.6% completed ≥1 follow-up survey during the first 6 months. Thirty-one percent of participants had ≥1 symptom alert at baseline and 74% had ≥1 symptom alert during follow-up. The proportions of participants for whom pathway-concordant symptom management was documented at each time point ranged from 12.8% to 36.6%. Twenty-eight participants (11.2%) discontinued ET by 12 months.

CONCLUSION

Symptom monitoring with ePROs during adjuvant ET is feasible. Despite infrequent documentation of pathway-concordant symptom management after symptom alerts, ePROs were associated with favorable short-term ET persistence.

Social inequality in cancer survivorship: Educational differences in health-related quality of life among 27,857 cancer survivors in Denmark

BACKGROUND

With a growing population of cancer survivors in Denmark, the evaluation of health-related quality of life (HRQoL) has become increasingly important. We describe variations in HRQoL between educational groups in a national population of cancer survivors.

METHODS

We conducted a cross-sectional questionnaire study among breast, prostate, lung, and colon cancer survivors diagnosed in 2010-2019 in Denmark. We used the EORTC QLQ-C30 to assess HRQoL including physical, role, emotional, cognitive, social functioning, and symptoms (fatigue, nausea and vomiting, pain, dyspnea, insomnia, appetite loss, constipation, diarrhea, and financial difficulties). Information on educational level and clinical data were extracted from national registers and clinical databases. Levels of impaired functioning and severe symptoms were identified using newly established thresholds for clinical importance. Multivariate logistic regression was used to examine associations between education and HRQoL. All statistical tests were 2-sided.

RESULTS

In total, 27,857 (42%) participated in the study. Up to 72% and 75% of cancer survivors with short education (≤9 years) reported impaired functioning and severe symptoms, respectively. Cancer survivors with short compared to long education (>12 years) were more likely to report impaired functioning and severe symptoms, with for example significantly higher odds ratios (ORs) for impaired physical function (breast OR = 2.41, 99% CI = 2.01-2.89; prostate OR = 1.81, 99% CI = 1.48-2.21; lung OR = 2.97, 99% CI = 1.95-4.57; and colon cancer OR = 1.69, 99% CI = 1.28-2.24).

CONCLUSIONS

Cancer survivors with short education are at greater risk of impaired HRQoL than survivors with long education 2-12 years after diagnosis. This underscores the need for systematic screening and symptom management in cancer aftercare, in order to reach all cancer survivors, also cancer survivors with short education.

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.

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.

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.

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

PURPOSE

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

METHODS

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

RESULTS

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

CONCLUSION

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

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.

Predictors of adherence and the role of primary non-adherence in antihormonal treatment of breast cancer

BACKGROUND

Antihormonal treatment for hormone receptor (HR) positive breast cancer has highly beneficial effects on both recurrence rates and survival. We investigate adherence and persistence in this group of patients.

METHODS

The study population comprised 1192 patients with HR-positive breast cancer who were prescribed adjuvant antihormonal treatment from 2004 to 2013. Adherence was defined as a medical possession ratio (MPR) of ≥80.

RESULTS

Of the 1192 included patients, 903 (75.8%) were adherent and 289 (24.2%) were non-adherent. Primary non-adherence was seen in 101 (8.5%) patients. The extremes of age (< 40 and ≥ 80 years) were associated with poor adherence. Patients with metastasis to axillary lymph nodes and those who received radiotherapy and/or chemotherapy were more likely to be adherent. Better adherence was also shown for those who switched medication at 2 years after diagnosis. Primary non-adherence seems to be associated with cancers with a good prognosis.

CONCLUSION

Adherence to antihormonal therapy for breast cancer is suboptimal. Primary non-adherence occurs among patients with a relatively good prognosis. Non-adherent patients tend to terminate their antihormonal therapy in the initial part of the treatment period. Targeted interventions to improve adherence should be focused on the first part of the treatment period.

Network Modeling of Complex Time-Dependent Changes in Patient Adherence to Adjuvant Endocrine Treatment in ER+ Breast Cancer

Early patient discontinuation from adjuvant endocrine treatment (ET) is multifactorial and complex: Patients must adapt to various challenges and make the best decisions they can within changing contexts over time. Predictive models are needed that can account for the changing influence of multiple factors over time as well as decisional uncertainty due to incomplete data. AtlasTi8 analyses of longitudinal interview data from 82 estrogen receptor-positive (ER+) breast cancer patients generated a model conceptualizing patient-, patient-provider relationship, and treatment-related influences on early discontinuation. Prospective self-report data from validated psychometric measures were discretized and constrained into a decisional logic network to refine and validate the conceptual model. Minimal intervention set (MIS) optimization identified parsimonious intervention strategies that reversed discontinuation paths back to adherence. Logic network simulation produced 96 candidate decisional models which accounted for 75% of the coordinated changes in the 16 network nodes over time. Collectively the models supported 15 persistent end-states, all discontinued. The 15 end-states were characterized by median levels of general anxiety and low levels of perceived recurrence risk, quality of life (QoL) and ET side effects. MIS optimization identified 3 effective interventions: reducing general anxiety, reinforcing pill-taking routines, and increasing trust in healthcare providers. Increasing health literacy also improved adherence for patients without a college degree. Given complex regulatory networks’ intractability to end-state identification, the predictive models performed reasonably well in identifying specific discontinuation profiles and potentially effective interventions.

Adesão à Terapia Hormonal Adjuvante com Tamoxifeno e Anastrozol utilizando ARMS-12 e MMAS-4

Introdução: Entre os canceres de mama, aproximadamente 75% das mulheres são receptores hormonais positivos, sendo estas mais propensas a responderem a hormonioterapia com anastrozol e tamoxifeno. Apesar de eficazes, apresentam taxas significativas de não adesão. Objetivo: Avaliar a adesão a terapia hormonal adjuvante com tamoxifeno e anastrozol em pacientes atendidos nos Ambulatórios da Mastologia e de Quimioterapia do Hospital São Paulo entre os anos de 2019 e 2020. Método: Estudo transversal com 102 mulheres, realizado entre os meses de setembro de 2019 e marco de 2020. A adesão a terapia hormonal adjuvante foi avaliada utilizando-se as escalas Morisky Medication Adherence Scale (MMAS-4) e Adherence to Refills and Medications Scale of 12 items (ARMS-12). Resultados: A média de idade foi de 61,5 anos (59,3-63,6). Entre as pacientes, 27,7% faziam uso de tamoxifeno e 72,3% de anastrozol. Relataram desconforto em relação ao uso do medicamento 84,4%, sendo as ondas de calor (42,2%) e as dores articulares (55,9%) os mais frequentes. A escala de ARMS>12 foi pontuada por 79,2%; cerca de 90% das mulheres pontuaram a MMAS-4 até dois pontos, porém não houve diferença significativa entre os tipos de hormônios utilizados para escalas de adesão (p=0,815 e p=0,489). Conclusão: A adesão a hormonioterapia observada foi relativamente baixa, independentemente da endocrinoterapia, podendo essas pacientes estarem em risco de inadequação quanto a resposta clínica.

Association of treatment-emergent symptoms identified by patient-reported outcomes with adjuvant endocrine therapy discontinuation

Many patients discontinue endocrine therapy for breast cancer due to intolerance. Identification of patients at risk for discontinuation is challenging. The minimal important difference (MID) is the smallest change in a score on a patient-reported outcome (PRO) that is clinically significant. We evaluated the association between treatment-emergent symptoms detected by worsening PRO scores in units equal to the MID with discontinuation. We enrolled females with stage 0-III breast cancer initiating endocrine therapy in a prospective cohort. Participants completed PROs at baseline, 3, 6, 12, 24, 36, 48, and 60 months. Measures included PROMIS pain interference, fatigue, depression, anxiety, physical function, and sleep disturbance; Endocrine Subscale of the FACT-ES; and MOS-Sexual Problems (MOS-SP). We evaluated associations between continuous PRO scores in units corresponding to MIDs (PROMIS: 4-points; FACT-ES: 5-points; MOS-SP: 8-points) with time to endocrine therapy discontinuation using Cox proportional hazards models. Among 321 participants, 140 (43.6%) initiated tamoxifen and 181 (56.4%) initiated aromatase inhibitor (AI). The cumulative probability of discontinuation was 23% (95% CI 18-27%) at 48 months. For every 5- and 4-point worsening in endocrine symptoms and sleep disturbance respectively, participants were 13 and 14% more likely to discontinue endocrine therapy respectively (endocrine symptoms HR 1.13, 95% CI 1.02-1.25, p = 0.02; sleep disturbance HR 1.14, 95% CI 1.01-1.29, p = 0.03). AI treatment was associated with greater likelihood of discontinuation than tamoxifen. Treatment-emergent endocrine symptoms and sleep disturbance are associated with endocrine therapy discontinuation. Monitoring for worsening scores meeting or exceeding the MID on PROs may identify patients at risk for discontinuation.

Comparison of Approaches for Measuring Adherence and Persistence to Oral Oncologic Therapies in Patients Diagnosed with Metastatic Renal Cell Carcinoma

BACKGROUND

Adherence and persistence studies face several methodologic difficulties, including short-term mortality. We compared approaches to quantify adherence and persistence to first line (1L) oral targeted therapy (TT) in patients diagnosed with metastatic renal cell carcinoma (mRCC).

METHODS

Patients with mRCC ages 66 years or more who initiated TTs within 4 months of diagnosis were identified in the Surveillance, Epidemiology, and End Results Medicare-linked database (2007-2015). Adherence [proportion of days covered (PDC) >80%] was calculated using (i) PDC with a fixed 6-month denominator including then excluding patients who died within the 6 months and (ii) PDC with a denominator measuring time on treatment. Risk of nonpersistence was obtained by censoring death or treating death as a competing risk using cumulative incidence functions.

RESULTS

Among 485 patients with mRCC initiating a 1L oral TT (sunitinib, 64%; pazopanib, 25%; other, 11%), 40% died within 6 months. Adherence was higher after restricting to patients who survived (60%) compared with including those patients and assigning zero days covered after death (47%). Risk of nonpersistence was higher when censoring patients at death, 0.91 [95% confidence interval (CI), 0.88-0.94], compared with treating death as a competing risk, 0.75 (95% CI, 0.71-0.79).

CONCLUSIONS

Different approaches to handling death resulted in different adherence and persistence estimates in the metastatic setting. Future studies should explicitly report the proportion of patient deaths over time and explore appropriate methods to account for death as competing risk.

IMPACT

Use of several approaches can provide a more comprehensive picture of medication-taking behavior in the metastatic setting where death is a major competing risk.

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

Purpose

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

Methods

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

Results

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

Conclusion

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

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

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Self-reported adherence may overestimate patient adherence.

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Nineteen recurring factors were associated with adherence.

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Having adverse effects was negatively associated with adherence.

Trends in endocrine therapy prescription and survival in patients with non-metastatic hormone receptor positive breast cancer treated with endocrine therapy: A population based-study

PURPOSE

To identify prognostic factors of invasive-disease free survival (iDFS) in women with non-metastatic hormone receptor positive (HR+) breast cancer (BC) in daily routine practice.

METHODS

We performed a retrospective study using data from the Côte d'Or breast and gynecological cancer registry in France. All women diagnosed with primary invasive non-metastatic HR + BC from 1998 to 2015 and treated by endocrine therapy (ET) were included. Women with bilateral tumors or who received ET for either metastasis or relapse were excluded. We performed adjusted survival analysis and Cox regression to identify prognostic factors of iDFS.

RESULTS

A total of 3976 women were included. Age at diagnosis, ET class, SBR grade, treatment, stage and comorbidity were independently associated with iDFS. Women who had neither surgery nor radiotherapy had the highest risk of recurrence (HR = 3.75, 95%CI [2.65-5.32], p < 0.0001). Receiving aromatase inhibitors (AI) was associated with a lower risk of recurrence (HR = 0.70, 95%CI [0.54-0.90], p = 0.055) compared to tamoxifen. Compared to women with no comorbidities, women with 1 or 2 comorbidities were more likely to receive AI (OR = 1.63, 95%CI [1.22-2.17], p = 0.0009).

CONCLUSIONS

Comorbidities, age at diagnosis and previous treatment were associated with iDFS in non-metastatic HR + BC patients. This study also showed that women who received tamoxifen for their cancer experienced worse iDFS compared to women treated with AI.

A Smartphone-Based App to Improve Adjuvant Treatment Adherence to Multidisciplinary Decisions in Patients With Early-Stage Breast Cancer: Observational Study

BACKGROUND

Multidisciplinary treatment (MDT) and adjuvant therapy are associated with improved survival rates in breast cancer. However, nonadherence to MDT decisions is common in patients. We developed a smartphone-based app that can facilitate the full-course management of patients after surgery.

OBJECTIVE

This study aims to investigate the influence factors of treatment nonadherence and to determine whether this smartphone-based app can improve the compliance rate with MDTs.

METHODS

Patients who had received a diagnosis of invasive breast cancer and had undergone MDT between March 2013 and May 2019 were included. Patients were classified into 3 groups: Pre-App cohort (November 2017, before the launch of the app); App nonused, cohort (after November 2017 but not using the app); and App used cohort (after November 2017 and using the app). Univariate and multivariate analyses were performed to identify the factors related to MDT adherence. Compliance with specific adjuvant treatments, including chemotherapy, radiotherapy, endocrine therapy, and targeted therapy, was also evaluated.

RESULTS

A total of 4475 patients were included, with Pre-App, App nonused, and App used cohorts comprising 2966 (66.28%), 861 (19.24%), and 648 (14.48%) patients, respectively. Overall, 15.53% (695/4475) patients did not receive MDT recommendations; the noncompliance rate ranged from 27.4% (75/273) in 2013 to 8.8% (44/500) in 2019. Multivariate analysis demonstrated that app use was independently associated with adherence to adjuvant treatment. Compared with the patients in the Pre-App cohort, patients in the App used cohort were less likely to deviate from MDT recommendations (odds ratio [OR] 0.61, 95% CI 0.43-0.87; P=.007); no significant difference was found in the App nonused cohort (P=.77). Moreover, app use decreased the noncompliance rate for adjuvant chemotherapy (OR 0.41, 95% CI 0.27-0.65; P<.001) and radiotherapy (OR 0.49, 95% CI 0.25-0.96; P=.04), but not for anti-HER2 therapy (P=.76) or endocrine therapy (P=.39).

CONCLUSIONS

This smartphone-based app can increase MDT adherence in patients undergoing adjuvant therapy; this was more obvious for adjuvant chemotherapy and radiotherapy.

Prevalence and predictors of medication non-adherence among people living with multimorbidity: a systematic review and meta-analysis

OBJECTIVES

This systematic review aimed to describe medication non-adherence among people living with multimorbidity according to the current literature, and synthesise predictors of non-adherence in this population.

METHODS

A systematic review was conducted according to the Preferred Reporting Items for Systematic reviews and Meta-Analyses. PubMed, EMBASE, CINAHL and PsycINFO were searched for relevant articles published in English language between January 2009 and April 2019. Quantitative studies reporting medication non-adherence and/or predictors of non-adherence among people with two or more chronic conditions were included in the review. A meta-analysis was conducted with a subgroup of studies that used an inclusive definition of multimorbidity to recruit participants, rather than seeking people with specific conditions. Remaining studies reporting prevalence and predictors of non-adherence were narratively synthesised.

RESULTS

The database search produced 10 998 records and a further 75 were identified through other sources. Following full-text screening, 178 studies were included in the review. The range of reported non-adherence differed by measurement method, at 76.5% for self-report, 69.4% for pharmacy data, and 44.1% for electronic monitoring. A meta-analysis was conducted with eight studies (n=8949) that used an inclusive definition of multimorbidity to recruit participants. The pooled prevalence of non-adherence was 42.6% (95% CI: 34.0 - 51.3%, k=8, I²=97%, p<0.01). The overall range of non-adherence was 7.0%-83.5%. Frequently reported correlates of non-adherence included previous non-adherence and treatment-related beliefs.

CONCLUSIONS

The review identified a heterogeneous literature in terms of conditions studied, and definitions and measures of non-adherence used. Results suggest that future attempts to improve adherence among people with multimorbidity should determine for which conditions individuals require most support. The variable levels of medication non-adherence highlight the need for more attention to be paid by healthcare providers to the impact of multimorbidity on chronic disease self-management.

PROSPERO REGISTRATION NUMBER

CRD42019133849.

Machine Learning to Predict Tamoxifen Nonadherence Among US Commercially Insured Patients With Metastatic Breast Cancer

PURPOSE

Adherence to tamoxifen citrate among women diagnosed with metastatic breast cancer can improve survival and minimize recurrence. This study aimed to use real-world data and machine learning (ML) methods to classify tamoxifen nonadherence.

METHODS

A cohort of women diagnosed with metastatic breast cancer from 2012 to 2017 were identified from IBM MarketScan Commercial Claims and Encounters and Medicare claims databases. Patients with < 80% proportion of days coverage in the year following treatment initiation were classified as nonadherent. Training and internal validation cohorts were randomly generated (4:1 ratio). Clinical procedures, comorbidity, treatment, and health care encounter features in the year before tamoxifen initiation were used to train logistic regression, boosted logistic regression, random forest, and feedforward neural network models and were internally validated on the basis of area under receiver operating characteristic curve. The most predictive ML approach was evaluated to assess feature importance.

RESULTS

A total of 3,022 patients were included with 40% classified as nonadherent. All models had moderate predictive accuracy. Logistic regression (area under receiver operating characteristic 0.64) was interpreted with 94% sensitivity (95% CI, 89 to 92) and 0.31 specificity (95% CI, 29 to 33). The model accurately classified adherence (negative predictive value 89%) but was nondiscriminate for nonadherence (positive predictive value 48%). Variable importance identified top predictive factors, including age ≥ 55 years and pretreatment procedures (lymphatic nuclear medicine, radiation oncology, and arterial surgery).

CONCLUSION

ML using baseline administrative data predicts tamoxifen nonadherence. Screening at treatment initiation may support personalized care, improve health outcomes, and minimize cost. Baseline claims may not be sufficient to discriminate adherence. Further validation with enriched longitudinal data may improve model performance.

Literature review and case report of bilateral intracystic papillary carcinoma associated with an invasive ductal carcinoma in a male breast

Intracystic papillary carcinoma (IPC) is a rare tumor with good prognosis that occurs in only 5% to 7.5% of male breast cancer. We report a case of a 46-year-old man who presented a brown nipple discharge a few months ago. He had a bilateral IPC and an invasive ductal carcinoma on the right breast. A double mastectomy was then performed with a bilateral sentinel lymph node biopsy, and he received chemotherapy, radiotherapy, and hormonotherapy. Two years after the diagnosis, the patient recovered and was free of recurrence. Considering the scarcity of this tumor type, we conducted a systematic literature review on the PubMed of all the cases of IPC in men. The clinical presentation, imaging, and treatment of the 43 case reports from the 41 articles selected were described. Furthermore, no clear guidelines for IPC management are available. Conservative surgery should also be preferred, and a sentinel lymph node biopsy should be performed systematically. Moreover, radiotherapy should be proposed in the case of conservative surgery, and hormone therapy could be proposed in the case of invasive IPC or IPC associated with a ductal carcinoma in situ.

Further Evidence That OPG rs2073618 Is Associated With Increased Risk of Musculoskeletal Symptoms in Patients Receiving Aromatase Inhibitors for Early Breast Cancer

Background

Aromatase inhibitors (AI) reduce recurrence and death in patients with early-stage hormone receptor-positive (HR +) breast cancer. Treatment-related toxicities, including AI-induced musculoskeletal symptoms (AIMSS), are common and may lead to early AI discontinuation. The objective of this study was to replicate previously reported associations for candidate germline genetic polymorphisms with AIMSS.

Methods

Women with stage 0-III HR + breast cancer initiating adjuvant AI were enrolled in a prospective clinic-based observational cohort. AIMSS were assessed by patient-reported outcomes (PRO) including the PROMIS pain interference and physical function measures plus the FACT-ES joint pain question at baseline and after 3 and 6 months. For the primary analysis, AIMSS were defined as ≥ 4-point increase in the pain interference T-score from baseline. Secondary AIMSS endpoints were defined as ≥ 4-point decrease in the physical function T-score from baseline and as ≥ 1-point increase on the FACT-ES joint pain question from baseline. The primary hypothesis was that TCL1A rs11849538 would be associated with AIMSS. Twelve other germline variants in CYP19A1, VDR, PIRC66, OPG, ESR1, CYP27B1, CYP17A1, and RANKL were also analyzed assuming a dominant genetic effect and prespecified direction of effect on AIMSS using univariate logistic regression with an unadjusted α = 0.05. Significant univariate associations in the expected direction were adjusted for age, race, body mass index (BMI), prior taxane, and the type of AI using multivariable logistic regression.

Results

A total of 143 participants with PRO and genetic data were included in this analysis, most of whom were treated with anastrozole (78%) or letrozole (20%). On primary analysis, participants carrying TCL1A rs11849538 were not more likely to develop AIMSS (odds ratio = 1.29, 95% confidence interval: 0.55-3.07, p = 0.56). In the statistically uncorrected secondary analysis, OPG rs2073618 was associated with AIMSS defined by worsening on the FACT-ES joint pain question (OR = 3.33, p = 0.004), and this association maintained significance after covariate adjustment (OR = 3.98, p = 0.003).

Conclusion

Carriers of OPG rs2073618 may be at increased risk of AIMSS. If confirmed in other cohorts, OPG genotyping can be used to identify individuals with HR + early breast cancer in whom alternate endocrine therapy or interventions to enhance symptom detection and implement strategies to reduce musculoskeletal symptoms may be needed.

Adherence to Adjuvant Hormonal Therapy and Associated Factors Among Women with Breast Cancer Attending the Tikur Anbessa Specialized Hospital, Addis Ababa Ethiopia, 2019: A Cross-sectional Study

BACKGROUND

In breast cancer patients, adherence to adjuvant hormone therapy (AHT) is uncertain. Seven in every 10 patients were hormone receptor positive and adjuvant hormone therapy (AHT) is prescribed for 5-10 years for a woman with breast cancer. Therefore, the aim of this research was to examine adherence to adjuvant hormone therapy and related factors among women with breast cancer attending the Tikur Anbessa Specialized Hospital Oncology Center.

METHODS

An institutional-based cross-sectional study was conducted from March to April, 2019. Systematic random sampling technique was used to select participants. A semi-structured questionnaire was used. Medication possession ratio (MPR) was used where score ≥80% was adherence. Data were entered in EpiData version 4.4.2.1 and transferred to SPSS version 25, and analyzed using binary logistic regression.

RESULTS

Out of 216 women with breast cancer 209 participated in the study with a response rate of 97%. The overall adherence in this study was 77.5%. Getting social support (OR=3.959, 95%CI: 1.570-9.980), being on anastrozole (OR=0.139, 95%CI: 0.040-0.485), getting a thorough therapeutic communication about treatment (OR=4.590, 95%CI: 1.061-19.863), undergoing mastectomy (OR=0.215, 95%CI: 0.059-0.788), having side effects (OR=0.210, 95%CI: 0.085-0.517) were found to be significantly associated with adherence to AHT.

CONCLUSION

In general, the overall adherence to AHT was 77.5% for women with breast cancer. Factors such as types of adjuvant hormone therapy, lack of side effects, mastectomy, getting social support, and thorough therapeutic communication were strongly linked with adherence to them.

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

PURPOSE

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

EXPERIMENTAL DESIGN

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

RESULTS

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

CONCLUSIONS

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

Impact of patients' refusal to undergo adjuvant treatment measures on survival

PURPOSE

Breast cancer patients receive treatment recommendations from multidisciplinary tumour boards. To determine the consequences of patients' refusal of such recommendations, we analysed the database of the Centre for Breast Cancer at the Ortenau Clinic in Offenburg, Germany.

METHODS

A total of 4315 patients with non-metastatic primary breast cancer, treated between 1997 and 2019, were analysed with descriptive analyses, Kaplan-Meier survival analyses, and Cox regression analyses regarding the effects of their refusal.

RESULTS

About 10.7% of the patients rejected the treatment advice. These were significantly elderly (F = 74.4; p < 0.001; one-way ANOVA), with greater tumour size (F = 36.7; p < 0.001; one-way ANOVA), a higher number of affected lymph nodes (F = 4.2; p = .039; one-way ANOVA), and more poorly differentiated tumours (χ² = 16.8; df = 2; p < 0.001). The refusal of adjuvant treatment resulted in higher rates of local recurrences (χ²_radiotherapy = 109.1; df = 1; p < 0.001, χ²_chemotherapy = 18.3; df = 1; p < 0.001, χ²_endocrine = 32.5; df = 1; p < 0.001) and poorer overall survival (χ²_radiotherapy = 184.9; df = 6; p < 0.001; χ²_chemotherapy = 191.8; df = 6; p < 0.001).

CONCLUSIONS

All parts of the adjuvant treatment of breast cancer are clearly associated with improvements regarding disease-free and overall survival. To answer open questions about the background of patients' refusal, an analysis of prospective data collections seems necessary. In addition, patient communication should be improved so that patients understand the background of the multidisciplinary tumour board and the potential consequences of their refusal.

Endocrine treatment and incidence of relapse in women with oestrogen receptor-positive breast cancer in Europe: a population-based study

PURPOSE

Endocrine therapy (ET) is the mainstream adjuvant treatment for ER-positive breast cancer (BC). We analysed 9293 ER-positive BC patients diagnosed in nine European countries in 2009-2013 to investigate how comorbidities at diagnosis, age, stage and subtype affected ET use over time, and relapse.

METHODS

Adjusted odds ratios (ORs) and 95% confidence intervals (95%CIs) of receiving ET were estimated according to Charlson comorbidity, age, stage and subtype using logistic regression. The 2-year cumulative incidence and adjusted sub-hazard ratios (SHRs) of relapse were estimated using competing risk analysis, with all-cause death as the competing event. The z-test was used to assess differences in the proportion of patients receiving ET in 1996-1998 and 2009-2013.

RESULTS

Ninety percent of the patients started adjuvant ET, range 96% (Belgium, Estonia, Slovenia, Spain)-75% (Switzerland). ORs of starting ET were lower for women aged > 75 years, with severe comorbidities, or luminal B HER2-positive cancer. The factors independently increasing the risk of relapse were: not receiving ET (SHR 2.26, 95%CI 1.02-5.03); severe comorbidity (SHR 1.94, 95%CI 1.06-3.55); luminal B, either HER2 negative (SHR 3.06, 95%CI 1.61-5.79) or positive (SHR 3.10, 95%CI 1.36-7.07); stage II (SHR 3.20, 95%CI 1.56-6.57) or stage III (SHR 7.41, 95%CI 3.48-15.73). ET use increased significantly but differently across countries from 51-85% in 1996-1998 to 86-96% in 2009-2013.

CONCLUSIONS

ER-positive BC patients in Europe are increasingly prescribed ET but between-country disparities persist. Older women and women with severe comorbidity less frequently receive ET. ET omission and severe comorbidity independently predict early disease relapse.