Half of breast cancer patients discontinue tamoxifen and any endocrine treatment before the end of the recommended treatment period of 5 years: a population-based analysis

Characterizing safety, toxicity, and breast cancer risk reduction using a long-term fulvestrant eluting implant

For individuals at high risk of developing breast cancer, interventions to mitigate this risk include surgical removal of their breasts and ovaries or five years treatment with the anti-estrogen tamoxifen or aromatase inhibitors. We hypothesized that a silicone based anti-estrogen-eluting implant placed within the breast would provide the risk reduction benefit of hormonal therapy, but without the adverse effects that limit compliance. To this end, we demonstrate that when placed adjacent to mammary tissue in the 7,12-dimethylbenz[a]anthracene-induced rat breast cancer model a fulvestrant-eluting implant delays breast cancer with minimal systemic exposure. Using adult female sheep, surgical placement of fulvestrant-eluting implants was safe and did not elicit significant breast tissue pathology when placed at the base of the udder for directed elution into the mammary tissue. At 30 days of elution, fulvestrant was found to penetrate mammary tissue forming a concentration gradient beyond 15 mm from the implant. Consistent with the small animal rat study, minimal systemic fulvestrant biodistribution was found. Together, these studies provide the proof of principle that a breast indwelling fulvestrant-eluting implant can reduce the risk of breast cancer and limit systemic exposure, while penetrating and distributing through breast tissue.

Effects of Adjuvant Endocrine Therapy-Specific Perceptions on Response to a Behavioral Intervention for Adjuvant Endocrine Therapy Adherence in Patients With Breast Cancer

PURPOSE

Adjuvant endocrine therapy (AET) is a life-saving medication for patients with hormone-sensitive breast cancer, yet many struggle with adherence, warranting behavioral intervention. In our recent trial, participation in a group cognitive behavioral intervention (STRIDE) for symptom management and adherence was associated with improvements in symptom distress, coping, quality of life, and mood. We now explore whether baseline patient- and medication-specific factors-which may be modifiable by clinician-led discussions-moderated the effect of STRIDE on adherence rates.

METHODS

From October 2019 to June 2021, 100 patients with early-stage breast cancer reporting AET-related distress were enrolled and randomly assigned to STRIDE or a medication monitoring (MM) control group. All patients stored their AET in electronic pill bottles to track objective adherence. Patients also self-reported their adherence on the Medication Adherence Report Scale-5 and their perceptions of AET on the Cancer Therapy Satisfaction Questionnaire at baseline. We conducted hierarchical linear modeling to test moderators of intervention effects on objective adherence rates. We report the time × group × moderator effects.

RESULTS

Among patients reporting greater perceived difficulties with AET adherence at baseline, STRIDE participants had higher adherence rates over time compared with MM (b = -13.80; SE = 4.56; P < .01). Patients with greater expectations of therapeutic benefit from AET also had improved adherence rates if they were assigned to STRIDE, versus MM (b = 0.25; SE = 0.10; P = .01). Patients who perceived taking AET as convenient and had been taking their AET for less time had higher adherence rates in STRIDE, versus MM.

CONCLUSION

The current study identified patient- and medication-specific factors that may augment AET adherence interventions and may be modifiable through clinician-led discussions, such as perceptions of adherence problems, therapeutic efficacy, and convenience of AET.

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.

Adherence to adjuvant endocrine therapy after breast cancer in Sweden - a nationwide cohort study in 1-, 3- and 5-year survivors with a focus on regional differences

BACKGROUND AND PURPOSE

Adjuvant endocrine treatment (AET) is crucial in early oestrogen receptor (ER)-positive breast cancer (BC), providing reduced recurrence rate and increased overall survival. The aim of this study was to estimate AET adherence rates by age at diagnosis and region in Sweden.

PATIENTS AND METHODS

In total, 10,422 women diagnosed with ER-positive BC in 2008-2010 were identified in the Swedish National BC Registry. Information on prescriptions and dispensation of AET was gathered through record linkage to the Swedish Prescription Registry. 1, 3- and 5-year medication possession ratios (MPRs) were calculated. Good adherence was set as MPR ≥ 80%.

RESULTS

The 1-, 3- and 5-year AET age-adjusted adherence rates were 94.4, 87.6 and 81.6%, respectively. The 1-, 3- and 5- year adherence rate was significantly highest in the South region (96.2, 90.5 and 86.2%). Regions with an oncologic clinic had higher adherence rate than regions without, 82.8% versus 75.5% at 5-year FU. Women at age 40-64 years (95.6, 89.9 and 84.1%) and 65-74 years at diagnosis (95.7, 89.5 and 84.6%) had significantly higher adherence rate than women ≥ 75 years at diagnosis (89.1, 79.2 and 68.3%).

INTERPRETATIONS

Despite guidelines being national, there were significant differences in adherence between regions in Sweden. As the largest differences were between age groups invited and not invited to mammography screening intervention should focus on women < 40 and ≥ 75 years at diagnosis. Further studies are needed to find strategies to increase overall adherence to AET in early BC.

Insights Into the Patient Experience of Hormone Therapy for Early Breast Cancer Treatment Using Patient Forum Discussions and Natural Language Processing

PURPOSE

Understanding the real-world experience of patients with early breast cancer (eBC) is imperative for optimizing outcomes and evolving patient care. However, there is a lack of patient-level data, hindering clinical development. This social listening study was performed to understand patient insights into symptoms and impacts of hormone therapy (HT) for eBC using posts from patient forums on breastcancer.org to inform future clinical research.

METHODS

Natural language processing (NLP) and machine learning techniques were used to identify themes related to eBC from a sample of 500,000 posts. After relevant data selection, 362,074 eBC posts were retained for further analysis of symptoms and impacts related to HT, as well as insights into symptom severity, pain locations, and symptom management using exercise and yoga.

RESULTS

Overall, 32 symptoms and nine impacts had significant associations with ≥one HT. Hot flush (relative risk [RR], 6.70 [95% CI, 3.36 to 13.36]), arthralgia (RR, 6.67 [95% CI, 3.53 to 12.59]), weight increased (RR, 4.83 [95% CI, 3.20 to 7.28]), mood swings (RR, 7.36 [95% CI, 5.75 to 9.42]), insomnia (RR, 4.76 [95% CI, 3.14 to 7.22]), and depression (RR, 3.05 [95% CI, 1.71 to 5.44]) demonstrated the strongest associations. Severe headache, dizziness, back pain, and muscle spasms showed significant associations with ≥one HT despite their low overall prevalence in eBC posts.

CONCLUSION

The social listening approach allowed the identification of real-world insights from posts specific to eBC HT from a large-scale online breast cancer forum that captured experiences from a uniquely diverse group of patients. Using NLP has a potential to scale analysis of patient feedback and reveal actionable insights into patient experiences of treatment that can inform the development of future therapies and improve the care of patients with eBC.

Obstetric and perinatal outcomes in women with previous breast cancer: a nationwide study of singleton births 1973-2017

STUDY QUESTION

What are the obstetric and perinatal outcomes in births to breast cancer survivors compared to women without previous breast cancer?

SUMMARY ANSWER

Women who conceived during the first 2 years following a breast cancer diagnosis had a higher risk for preterm birth, induced delivery, and cesarean section, while no increased risks were observed in births conceived later than 2 years after a breast cancer diagnosis.

WHAT IS KNOWN ALREADY

A recent meta-analysis found higher risks of cesarean section, preterm birth, low birthweight, and small for gestational age in pregnancies among breast cancer survivors. Less is known about rarer outcomes such as pre-eclampsia or congenital malformations.

STUDY DESIGN SIZE DURATION

We conducted a population-based matched cohort study including all breast cancer survivors who gave birth to singletons 1973-2017 in Sweden, identified through linkage between the Swedish Cancer Register, the Medical Birth Register, and the National Quality Register for Breast Cancer.

PARTICIPANTS/MATERIALS SETTINGS METHODS

Each birth following breast cancer (n = 926) was matched by maternal age at delivery, parity, and calendar year at delivery to 100 births in a comparator cohort of women (n = 92 490). Conditional logistic and multinomial regression models estimated relative risks (RR) with 95% CI. Subgroup analyses by time since diagnosis and type of treatment were performed.

MAIN RESULTS AND THE ROLE OF CHANCE

Previous breast cancer was associated with higher risks of induced delivery (RR; 1.3, 1.0-1.6), very preterm birth (RR; 1.8, 1.1-3.0), and planned preterm birth (RR; 1.6, 1.0-2.4). Women who conceived within 1 year after breast cancer diagnosis had higher risks of cesarean section (RR; 1.7, 1.0-2.7), very preterm birth (RR; 5.3, 1.9-14.8), and low birthweight (RR; 2.7, 1.4-5.2), while the risks of induced delivery (RR; 1.8, 1.1-2.9), moderately preterm birth (RR; 2.1, 1.2-3.7), and planned preterm birth (RR; 2.5, 1.1-5.7) were higher in women who conceived during the second year after diagnosis. Women who conceived later than 2 years after breast cancer diagnosis had similar obstetric risks to their comparators.

LIMITATIONS REASONS FOR CAUTION

As information on the end date of treatment was unavailable, the time between the date of diagnosis and conception was used as a proxy, which does not fully capture the effect of time since end of treatment. In addition, treatments and clinical recommendations have changed over the long study period, which may impact childbearing patterns in breast cancer survivors.

WIDER IMPLICATIONS OF THE FINDINGS

Risks of adverse obstetric outcomes in breast cancer survivors were confined to births conceived within 2 years of diagnosis. As family building holds significance for numerous young breast cancer patients, these findings are particularly important to inform both breast cancer survivors and clinicians about future reproductive outcomes.

STUDY FUNDING/COMPETING INTERESTS

This work was supported by the Swedish Cancer Society (grant number 22-2044 Pj A.L.V.J.), Karolinska Institutet Foundations (grant number: 2022-01696 F.E.L., 2022-01559 A.L.V.J.), and the Swedish Research Council (grant number: 2021-01657 A.L.V.J.). K.A.R.-W. is supported by grants from the Swedish Cancer Society (20 0170 F) and the Radiumhemmets Research Foundations for clinical researchers 2020-2026. The authors declare that they have no conflicts of interest.

TRIAL REGISTRATION NUMBER

N/A.

Association of Sarcopenia With Toxicity-Related Discontinuation of Adjuvant Endocrine Therapy in Women With Early-Stage Hormone Receptor-Positive Breast Cancer

PURPOSE

Sarcopenia, an age-related decline in muscle mass and physical function, is associated with increased toxicity and worse outcomes in women with breast cancer (BC). Sarcopenia may contribute to toxicity-related early discontinuation of adjuvant endocrine  therapy (aET) in women with hormone receptor-positive (HR+) BC but remains poorly characterized.

METHODS AND MATERIALS

This multicenter, retrospective cohort study included consecutive women with stage 0-II HR+ BC who received breast conserving therapy (lumpectomy and radiation therapy) and aET from 2011 to 2017 with a 5-year follow-up. Skeletal muscle index (SMI, cm2/m2) was analyzed using a deep learning model on routine cross-sectional radiation simulation imaging; sarcopenia was dichotomized according to previously validated reports. The primary endpoint was toxicity-related aET discontinuation; logistic regression analysis evaluated associations between SMI/sarcopenia and aET discontinuation. Cox regression analysis evaluated associations with time to aET toxicity, ipsilateral breast tumor recurrence (IBTR), and disease-free survival (DFS).

RESULTS

A total of 305 women (median follow-up, 89 months) were included with a median age of 67 years and early-stage BC (12% stage 0, 65% stage I). A total of 60 (20%) women experienced toxicity-related aET discontinuation. Sarcopenia was associated with toxicity-related early discontinuation of aET (odds ratio, 2.18; P = .036) and shorter time to aET toxicity (hazard ratio [HR], 1.62; P = .031). SMI or sarcopenia were not independently associated with IBTR or DFS; toxicity-related aET discontinuation was associated with worse IBTR (HR, 9.47; P = .002) and worse DFS (HR, 4.53; P = .001).

CONCLUSIONS

Among women with early-stage HR+ BC who receive adjuvant radiation therapy and hormone therapy, sarcopenia is associated with toxicity-related early discontinuation of aET. Further studies should validate these findings in women who did not receive adjuvant radiation therapy. These high-risk patients may be candidates for aggressive symptom management and/or alternative treatment strategies to improve outcomes.

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.

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.

Patients' views and experiences on the supported self-management/patient-initiated follow up pathway for breast cancer

PURPOSE

To explore patients' expectations and experience of Supportive Self-Management (SSM)/ Patient Initiated Follow Up (PIFU) following breast cancer treatments over a 12-month period.

METHODS

In total, 32/110 (29%) patient participants in the PRAGMATIC (Patients' experiences of a suppoRted self-manAGeMent pAThway In breast Cancer) study were interviewed at baseline, 3, 6, 9 and 12 months. Interviews in this sub-study used a mix-methods approach to explore understanding of the pathway, confidence in self-management, triggers to seek help and/or re-engage with the clinical breast team and impact of the COVID-19 pandemic. Responses to pre-assigned categories were summarised as counts/ percentages and collated in tabular or graphic format. Free responses were recorded verbatim and reviewed using framework analysis.

RESULTS

Participants regarded the SSM/PIFU pathway as a way to save time and money for them and the National Health Service (NHS) (14/32; 44%) and as a means of assuming responsibility for their own follow-up (18/32; 56%). Most maintained (very/somewhat) confidence in managing their BC follow-up care (baseline 31/32, 97%; 12 months 29/31, 93%). During the year, 19% (5/26) stopped endocrine therapy altogether because of side effects. Qualitative analysis revealed general satisfaction with SSM/PIFU and described the breast care nurses as reassuring and empathic. However, there was a lingering anxiety about identifying signs and symptoms correctly, particularly for those with screen-detected cancers. There was also uncertainty about who to contact for psychological support. The COVID-19 pandemic discouraged some participants from contacting the helpline as they did not want to overburden the NHS.

CONCLUSIONS

The results show that during the first year on the SSM/PIFU pathway, most patients felt confident managing their own care. Clinical teams should benefit from understanding patients' expectations and experiences and potentially modify the service for men with BC and/or those with screen-detected breast cancers.

A long-term fulvestrant eluting implant is safe, non-toxic, and reduces the risk of breast cancer in in vivo models

For individuals at high risk of developing breast cancer, interventions to mitigate this risk include surgical removal of their breasts and ovaries or five years treatment with the anti-estrogen tamoxifen or aromatase inhibitors. We hypothesized that a silicone based anti-estrogen-eluting implant placed within the breast would provide the risk reduction benefit of hormonal therapy, but without the adverse effects that limit compliance. To this end, we demonstrate that when placed adjacent to mammary tissue in the DMBA-induced rat breast cancer model a fulvestrant-eluting implant delays breast cancer with minimal systemic exposure. Using adult female sheep, fulvestrant-eluting implants were found to be safe and non-toxic when placed at the base of the udder for directed elution into the mammary tissue. At 30 days of elution, fulvestrant was found to penetrate mammary tissue forming a concentration gradient beyond 15 mm from the implant. Consistent with the small animal rat study, minimal systemic fulvestrant biodistribution was found. Together, these studies provide the proof of principle that a breast indwelling fulvestrant-eluting implant can reduce the risk of breast cancer and limit systemic exposure, while penetrating and distributing through breast tissue.

Value of therapeutic drug monitoring of endoxifen in Egyptian premenopausal patients with breast cancer given tamoxifen adjuvant therapy: A pilot study

BACKGROUND

The complex metabolic profile of tamoxifen anticancer drug and polymorphism in its metabolizing enzymes particularly CYP2D6 contribute to the high-observed inter-individual variability in its main active metabolite endoxifen. Therapeutic drug monitoring of endoxifen may play a key role in optimizing tamoxifen therapy, and control of both adverse effects and cancer recurrence. This pilot study aims to assess the clinical benefits of applying endoxifen measurement during tamoxifen therapy in patients with breast cancer.

METHODS

Adult premenopausal breast cancer patients ≥ 18 years who received tamoxifen at a fixed dose of 20 mg daily were included. The primary endpoint was to identify the inter-subject variability in serum concentration of the drug and its metabolites especially endoxifen, through fixation of the tamoxifen dose. The secondary endpoint was to check the correlation between endoxifen metabolite concentration and the development of tamoxifen's adverse effects and cancer recurrence.

RESULTS

Sixty patients were included in the study with a mean age of 38.4  ±  0.6 years (range: 26-50). The mean concentration of tamoxifen and endoxifen was 181  ±  9.6 ng/mL and 31.49 ng/mL, respectively. The inter-individual variability in concentrations for the drug and its active metabolite as estimated by the coefficient of variation percentage was in 41% and 31%, respectively. Cancer recurrence was observed in a group of patients (n  =  16) with an average endoxifen level of 24.48 ng/mL. Another group of patients (n  =  25) developed different tamoxifen adverse effects including hot flashes, vaginal bleeding, endometrial thickness, and ovarian cysts with the average endoxifen level of 38.61 ng/mL. The rest of the patients (n  =  19) who responded smoothly to the drug with no complications had an average endoxifen level of 31.37 ng/mL. Analysis of variance test showed a significant difference in endoxifen levels between the three groups (p  =  0.002).

CONCLUSION

The measurement of the endoxifen active metabolite of tamoxifen in breast cancer patients can help dose optimization in light of the observed wide inter-individual variability in drug fixed-dose related concentration of the metabolite. Monitoring of serum concentration of endoxifen can help to reveal, reduce and control tamoxifen's adverse effects and cancer recurrence.

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

BACKGROUND

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

METHODS

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

RESULTS

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

CONCLUSION

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

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

PURPOSE

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

METHODS

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

RESULTS

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

CONCLUSION

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

Development of the HT&Me intervention to support women with breast cancer to adhere to adjuvant endocrine therapy and improve quality of life

BACKGROUND

Breast cancer is the most common cancer in women worldwide. Approximately 80% of breast cancers are oestrogen receptor positive (ER+). Patients treated surgically are usually recommended adjuvant endocrine therapy (AET) for 5-10 years. AET significantly reduces recurrence, but up to 50% of women do not take it as prescribed.

OBJECTIVE

To co-design and develop an intervention to support AET adherence and improve health-related quality-of-life (QoL) in women with breast cancer.

METHODS

Design and development of the HT&Me intervention took a person-based approach and was guided by the Medical Research Council framework for complex interventions, based on evidence and underpinned by theory. Literature reviews, behavioural analysis, and extensive key stakeholder involvement informed 'guiding principles' and the intervention logic model. Using co-design principles, a prototype intervention was developed and refined.

RESULTS

The blended tailored HT&Me intervention supports women to self-manage their AET. It comprises initial and follow-up consultations with a trained nurse, supported with an animation video, a web-app and ongoing motivational 'nudge' messages. It addresses perceptual (e.g. doubts about necessity, treatment concerns) and practical (e.g. forgetting) barriers to adherence and provides information, support and behaviour change techniques to improve QoL. Iterative patient feedback maximised feasibility, acceptability, and likelihood of maintaining adherence; health professional feedback maximised likelihood of scalability.

CONCLUSIONS

HT&Me has been systematically and rigorously developed to promote AET adherence and improve QoL, and is complemented with a logic model documenting hypothesized mechanisms of action. An ongoing feasibility trial will inform a future randomised control trial of effectiveness and cost-effectiveness.

Persistence with tamoxifen and aromatase inhibitors in Germany: a retrospective cohort study with 284,383 patients

PURPOSE

The aim of this study was to analyze the persistence of women on tamoxifen (TAM) and aromatase inhibitors (AIs) in Germany, and to investigate possible determinants of non-persistence.

METHODS

The present retrospective cohort study was based on the IQVIA longitudinal prescription database (LRx). The study included women with an initial prescription of TAM or AIs (anastrozole, letrozole, and exemestane) between January 2016 and December 2020 (index date). Kaplan-Meier analyses were performed to show the persistence for TAM and AI, using a therapy gap of 90 or 180 days, respectively. A multivariable Cox proportional hazards regression model was further used to estimate the relationship between non-persistence and drug prescription (AI versus TAM), age, and the specialty of the physician initiating therapy (gynecologist, oncologist, or general practitioner).

RESULTS

Up to 5 years after the index date, only 35.1% of AI and 32.5% of TAM patients were continuing therapy when therapy discontinuation was defined as at least 90 days without therapy. Using a 180-day therapy gap, 51.9% of AI and 50.4% of TAM patients remained on therapy after 5 years. Cox regression models reveal that initial therapy with TAM (HR 1.06, 95% CI 1.04-1.07), therapy initiation by oncologists (HR 1.09, 95% CI 1.07-1.11), or general practitioners (HR 1.24, 95% CI 1.21-1.27) and age ≤ 50 (HR 1.08, 95% CI 1.06-1.10) were significantly associated with an increased risk of therapy discontinuation.

CONCLUSION

Overall, the present study indicates that persistence rates are low in all age groups for both TAM and AI treatment. We found several factors (e.g., physician specialty, younger age, and type of endocrine therapy) to be associated with an increased risk for non-persistence.

Cost-Effectiveness Analysis of MammaPrint® to Guide the Use of Endocrine Therapy in Patients with Early-Stage Breast Cancer

BACKGROUND

Gene expression profiling tests can predict the risk of disease recurrence and select patients who are expected to benefit from therapy, while allowing other patients to forgo therapy. For breast cancers, these tests were initially designed to tailor chemotherapy decisions, but recent evidence suggests that they may also guide the use of endocrine therapy. This study evaluated the cost effectiveness of a prognostic test, MammaPrint^®, to guide the use of adjuvant endocrine therapy in patients eligible according to Dutch treatment guidelines.

METHODS

We constructed a Markov decision model to calculate the lifetime costs (in 2020 Euros) and effects (survival and quality-adjusted life-years) of MammaPrint^® testing versus usual care (endocrine therapy for all patients) in a simulated cohort of patients. The population of interest includes patients for whom MammaPrint^® testing is currently not indicated, but for whom it may be possible to safely omit endocrine therapy. We applied both a health care perspective and a societal perspective and discounted costs (4%) and effects (1.5%). Model inputs were obtained from published research (including randomized controlled trials), nationwide cancer registry data, cohort data and publicly available data sources. Scenario and sensitivity analyses were conducted to explore the impact of uncertainty around input parameters. Additionally, threshold analyses were performed to identify under which circumstances MammaPrint^® testing would be cost effective.

RESULTS

Adjuvant endocrine therapy guided by MammaPrint^® resulted in fewer side effects, more (quality-adjusted) life-years (0.10 and 0.07 incremental QALYS and LYs, respectively) and higher costs (€18,323 incremental costs) compared with the usual care strategy in which all patients receive endocrine therapy. While costs for hospital visits, medication costs and productivity costs were somewhat higher in the usual care strategy, these did not outweigh costs of testing in the MammaPrint^® strategy. The incremental cost-effectiveness ratio was €185,644 per QALY gained from a healthcare perspective and €180,617 from a societal perspective. Sensitivity and scenario analyses showed that the conclusions remained the same under changed input parameters and assumptions. Our results show that MammaPrint^® can become a cost-effective strategy when either the price of the test is reduced (> 50%), or the proportion of patients for which treatment is altered (i.e. those with ultra-low risk) increases to > 26%.

CONCLUSION

Standard MammaPrint^® testing to guide the use of endocrine therapy in our simulated patient population appears not to be a cost-effective strategy compared with usual care. The cost effectiveness of the test can be improved by reducing the price or preselecting a population more likely to benefit from the test.

Short-term changes in ultrasound tomography measures of breast density and treatment-associated endocrine symptoms after tamoxifen therapy

Although breast density decline with tamoxifen therapy is associated with greater therapeutic benefit, limited data suggest that endocrine symptoms may also be associated with improved breast cancer outcomes. However, it is unknown whether endocrine symptoms are associated with reductions in breast density after tamoxifen initiation. We evaluated treatment-associated endocrine symptoms and breast density change among 74 women prescribed tamoxifen in a 12-month longitudinal study. Treatment-associated endocrine symptoms and sound speed measures of breast density, assessed via novel whole breast ultrasound tomography (m/s), were ascertained before tamoxifen (T0) and at 1-3 (T1), 4-6 (T2), and 12 months (T3) after initiation. CYP2D6 status was genotyped, and tamoxifen metabolites were measured at T3. Using multivariable linear regression, we estimated mean change in breast density by treatment-associated endocrine symptoms adjusting for age, race, menopausal status, body mass index, and baseline density. Significant breast density declines were observed in women with treatment-associated endocrine symptoms (mean change (95% confidence interval) at T1:-0.26 m/s (-2.17,1.65); T2:-2.12 m/s (-4.02,-0.22); T3:-3.73 m/s (-5.82,-1.63); p-trend = 0.004), but not among women without symptoms (p-trend = 0.18) (p-interaction = 0.02). Similar declines were observed with increasing symptom frequency (p-trends for no symptoms = 0.91; low/moderate symptoms = 0.03; high symptoms = 0.004). Density declines remained among women with detectable tamoxifen metabolites or intermediate/efficient CYP2D6 metabolizer status. Emergent/worsening endocrine symptoms are associated with significant, early declines in breast density after tamoxifen initiation. Further studies are needed to assess whether these observations predict clinical outcomes. If confirmed, endocrine symptoms may be a proxy for tamoxifen response and useful for patients and providers to encourage adherence.

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.

Facing points of view: Representations on adjuvant endocrine therapy of premenopausal patients after breast cancer and their healthcare providers in France. The FOR-AD study

PURPOSE

Adjuvant endocrine therapy (ET) for 5-10 years is the backbone of the therapeutic strategy in patients with hormone receptor positive (HR+) early breast cancer (BC). However, long-term adherence to adjuvant ET represents a major challenge for most patients. According to prior studies, side effects of adjuvant ET are an important reason for poor adherence. In contrast, better communication and relational bond between patients and healthcare providers (HCPs) may improve adherence. The FOR-AD (Focus on non-adherence) study aimed at better understanding the representation of adjuvant ET by patients and their HCPs, in order to improve the care process.

METHODS

Three focus groups of premenopausal women (receiving adjuvant ET for variable amount of time) and two focus groups of HCPs (including oncologists, pharmacists, and nurses) were conducted, each including around ten participants. Thematic analyses using a general inductive approach were constructed to report participants' representations.

RESULTS

Two main themes emerged across groups, and appeared of major importance. Representations on adjuvant ET were often homogenous within each group, but differed between patients and their HCPs. The relationship between both groups was considerably discussed, particularly its importance in facilitating adherence to adjuvant ET. Suggestions on improving the care process were also given, such as systematically including psychologists in follow-up care paths and having a nurse navigator follow patients under treatment with adjuvant ET.

CONCLUSION

The present qualitative exploration may help buildi future tailored interventions to improve adherence to adjuvant ET, in particular regarding the role of nurse navigators.

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.

Impact of Endocrine Therapy Adherence on Outcomes in Elderly Women with Early-Stage Breast Cancer Undergoing Lumpectomy Without Radiotherapy

BACKGROUND

National Comprehensive Center Network guidelines recommend radiotherapy (RT) omission in women age ≥ 70 years with estrogen receptor-positive (ER+), cN0, T1 tumors post-lumpectomy if they receive endocrine therapy (ET). However, little is known about the impact of poor adherence on locoregional recurrence (LRR) in elderly women forgoing RT.

METHODS

Women age ≥ 70 years with pT1-2 ER+ breast cancer undergoing lumpectomy without RT from 2004 to 2019 were identified from a prospectively maintained database. ET adherence, calculated as treatment duration over follow-up time up to 5 years, was determined by chart review. We compared clinicopathologic characteristics and rates of LRR between women with high adherence (≥ 80%), low adherence (< 80%), and no ET.

RESULTS

Of 968 women (27 bilateral cancers), adherence was high in 676 (70%) and low in 162 (17%); 130 (13%) took no ET. Younger age and use of aromatase inhibitor were associated with high adherence. On multivariable analysis, tumor size (hazard ratio [HR] 1.67, 95% confidence interval [CI] 1.03-2.68, p = 0.04) and high adherence (HR 0.13, 95% CI 0.07-0.26, p < 0.001) were significantly associated with LRR. At 53 months median follow-up, the 5-year rate of LRR was 3.1% (95% CI 2.4-3.9%) with high adherence, 14.7% (95% CI 11.7-17.7%) with low adherence, and 17.9% (95% CI 13.9-21.8%) with no ET (p < 0.01).

CONCLUSIONS

Although adherence to ET was high overall, in the 30% of women with low adherence or no ET, LRR rates were significantly increased. Counseling regarding the distinct toxicities of ET and RT can help patients choose the therapy to which they will likely adhere to.

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.

Rationale and usability findings of an e-health intervention to improve oral anticancer adherence among breast cancer survivors: The My Journey mindfulness study

BACKGROUND

Approximately 80% of breast cancer survivors are prescribed oral endocrine therapy (ET) medication for 5-10 years following primary treatment, making adherence to ET a critical aspect of cancer survivorship care. Despite the benefits of ET, non-adherence is problematic, and up to half of breast cancer survivors ave been documented to discontinue ET early. Our team developed My Journey, an online, mindfulness-based program designed to improve adherence to ET. This manuscript describes the usability testing of My Journey and the protocol development for the My Journey randomized feasibility trial.

METHODS

Usability participants were women (N = 15) with a diagnosis of hormone receptor-positive non-metastatic breast cancer who had initiated ET. Participant impressions and feedback were collected qualitatively and quantitatively using items on usefulness, satisfaction, and ease of use. Participants in the 8-week feasibility trial (N = 80) will be randomized to receive the web-based My Journey intervention or a health education comparison condition.

RESULTS

Quantitative feedback on the usability trial was favorable, with a mean overall usability score of 106.3 (SD = 7.7; Range: 83-115) indicating above average usability. Qualitative data showed that participants found several strengths in the initial design of the My Journey online tool and that participants liked the layout of My Journey.

CONCLUSIONS

Findings indicate that the My Journey online tool is useable. The program's feasibility is being evaluated in a randomized trial.

Systematic review of real-world studies evaluating the impact of medication non-adherence to endocrine therapies on hard clinical endpoints in patients with non-metastatic breast cancer

Breast cancer, one of the most common malignancies, is associated with significant economic and health burden both at the patient and societal level. Although medication non-adherence to endocrine breast cancer therapies is common, so far only limited systematic evidence has been available on its quantitative consequences, as previous systematic reviews focused mainly on factors contributing to medication non-adherence. The objective of this review was to explore the implications of medication non-adherence to endocrine therapies on hard clinical outcomes in breast cancer based on real-world studies. A systematic literature review was conducted on PubMed; empirical evidence on hard clinical endpoints (i.e., survival, disease-free survival, metastasis and recurrence) were extracted from uni- or multivariate statistical analyses from retrospective or prospective cohort studies. Of the 2,360 identified records, 12 studies met the inclusion criteria. Two studies identified significant positive association between medication non-adherence and the risk of distant metastasis, three articles between medication non-adherence and the recurrence of breast cancer, two studies between medication non-adherence- and non-persistence and of worse disease-free survival and eight articles between medication non-adherence and mortality. There was only one study where the positive association between medication adherence and survival did not apply to all subgroups. The strong evidence on the negative health consequences of non-adherence to breast cancer treatments indicates the need for the regular monitoring of medication adherence. Furthermore, explicit inclusion of adherence enhancing interventions into health policy agenda would be warranted to improve medication adherence also at a system level.

Patient-Reported Outcomes From Phase III Neoadjuvant Systemic Trial Comparing Neoadjuvant Chemotherapy With Neoadjuvant Endocrine Therapy in Pre-Menopausal Patients With Estrogen Receptor-Positive and HER2-Negative, Lymph Node-Positive Breast Cancer

We aimed to evaluate the patient-reported outcomes (PROs) in a prospective phase III clinical trial, comparing neoadjuvant endocrine therapy (NET) with conventional neoadjuvant chemotherapy (NCT) in patients with hormone status positive, lymph node-positive premenopausal breast cancer (NCT01622361). The patients were randomized prospectively to either 24 weeks of NCT with adriamycin plus cyclophosphamide followed by taxane or NET with gonadotropin-releasing hormone agonist and tamoxifen. The patients were examined at the surgery unit of a large tertiary care hospital with a comprehensive cancer center. PROs were assessed on the first day of the trial (day 1, baseline) and at the end of treatment, using the breast cancer module of the European Organisation for Research and Treatment of Cancer Quality of Life Questionnaire Core 23 (EORTC QLQ BR23). One hundred and eighty-seven patients were randomly assigned to chemotherapy (n=95) or endocrine therapy (n=92), and 174 patients completed 24 weeks of the neoadjuvant treatment period (n=87, in each group). Baseline scores were similar between the groups. After treatment, there were no statistically significant differences in the function scales, including body image, sexual functioning, and sexual enjoyment between the groups, although the endocrine treatment group showed a significant improvement in the future perspective (hazard ratio, 8.3; 95% confidence interval, 1.72-18.38; P = 0.021). Similarly, there were no statistically significant differences in the symptom scales between the groups, including adverse effects of systemic therapy, breast symptoms, arm symptoms, and upset about hair loss. In conclusion, overall PROs were similar in both treatment groups, except for "future perspective," which was significantly better in the NET group than in the NCT group.

CLINICAL TRIAL REGISTRATION

ClinicalTrials.Gov, identifier NCT01622361.

Association of Modifiable Risk Factors With Early Discontinuation of Adjuvant Endocrine Therapy: A Post Hoc Analysis of a Randomized Clinical Trial

IMPORTANCE

Early discontinuation of adjuvant endocrine therapy (ET) is problematic among breast cancer survivors, with previous studies suggesting that up to 50% of women do not adhere to the recommended full 5 years of ET treatment.

OBJECTIVE

To identify the association between early discontinuation of ET in the Trial Assigning Individualized Options for Treatment (TAILORx) and modifiable risk factors, polypharmacy, and types of additional medications such as antidepressants and opioids.

DESIGN, SETTING, AND PARTICIPANTS

This post hoc analysis includes a subgroup of 954 patients with breast cancer in TAILORx, a randomized clinical trial conducted from April 7, 2006, to October 6, 2010. All participants received a diagnosis of hormone receptor-positive, ERBB2-negative, axillary node-negative breast cancer and started ET within a year of study entry. Analyses were conducted in the intent-to-treat population. Statistical analysis took place from January 15, 2020, to April 6, 2021.

MAIN OUTCOMES AND MEASURES

Participants completed measures on cancer-related health-related quality of life including physical well-being and social well-being prior to initiating ET. Early discontinuation of ET was defined as discontinuation less than 4 years from initiation for reasons other than death or recurrence. Kaplan-Meier estimates were used to calculate discontinuation, and Cox proportional hazards regression joint prediction models were used to analyze the association between rates of adherence to ET with patient-level factors.

RESULTS

A total of 954 women (mean [SD] age, 56.6 [8.9] years) were included in this analysis. In a joint model, receipt of chemoendocrine therapy (vs receipt of ET only; hazard ratio [HR], 0.57; 95% CI, 0.35-0.92; P = .02) and age older than 40 years (vs ≤40 years; HR for 41-50 years, 0.39; 95% CI, 0.18-0.85; P = .02; HR for 51-60 years, 0.28; 95% CI, 0.13-0.60; P = .001; HR for 61-70 years, 0.40; 95% CI, 0.18-0.86; P = .02; and HR for >70 years, 0.23; 95% CI, 0.07-0.77; P = .02) were associated with a lower probability of early discontinuation of ET. Adjusted for these factors, a history of depression compared with no history of depression (HR, 1.82; 95% CI, 1.19-2.77; P = .005), worse physical well-being compared with better physical well-being (HR, 2.12; 95% CI, 1.30-3.45; P = .002), and worse social well-being compared with better social well-being (HR, 1.94; 95% CI, 1.20-3.13; P = .006) were individually and significantly associated with a higher probability of early discontinuation of ET. Only antidepressant use at study baseline was associated with early discontinuation (HR, 1.87; 95% CI, 1.23-2.84; P = .003).

CONCLUSIONS AND RELEVANCE

In this post hoc analysis of a randomized clinical trial, baseline patient-reported health-related quality of life components, such as poor social well-being, poor physical well-being, and comorbid depression, were significant risk factors for early discontinuation of endocrine therapies. These results support systematic screening for patient-reported outcomes and depressive symptoms to identify women at risk for discontinuation of ET.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT00310180.

Extending Adjuvant Endocrine Therapy for 10 Years: A Mixed-Methods Analysis of Women's Decision Making in an Online Breast Cancer Forum

An additional 5 years of treatment with adjuvant hormonal therapy, to complete 10 years of medication, is recommended to reduce the risk of breast cancer recurrence. Yet professionals and patients should balance this benefit against side effects and toxicities. Little is known about women’s decision making regarding persistence with extended endocrine therapy. In this study, we collected data from a UK online breast cancer forum to analyse patterns of persistence and its associated factors. A mixed-methods exploratory sequential design was used, with a qualitative analysis of text (n = 61 individuals) informing the development of a quantitative instrument to statistically analyse the prevalence of the findings (n = 130). Our findings identified three different groups of women who had to make decisions regarding persistence with treatment: those about to complete 5 years of therapy, those who decided to extend treatment, and those who were initially prescribed 10 years. Factors affecting persistence were, lack of self-efficacy in managing side effects, lack of reassurance about individual risk of recurrence, and impact on quality of life. Interventions such as training of healthcare professionals including risk communication, medication reviews by clinical pharmacists, and re-planning of services in follow-up care, should better support women’s needs in extended hormonal therapy.

Development of a self-management intervention to improve tamoxifen adherence in breast cancer survivors using an Intervention Mapping framework

OBJECTIVE

Up to 50% of women prescribed tamoxifen do not take it as prescribed for the full duration, which increases risk of recurrence and mortality. The current paper describes the development of a self-management intervention aiming to improve adherence in breast cancer survivors taking tamoxifen.

METHODS

The intervention was developed following an Intervention Mapping approach. The content of the intervention was determined by theories of health behaviour and empirical evidence. Development was an iterative process involving input from expert researchers, clinicians and patient representatives.

RESULTS

The intervention was designed to improve both intentional and unintentional non-adherence. Key features included modifying unhelpful illness and treatment beliefs, improving confidence for coping with side effects and developing strategies for remembering to take tamoxifen.

CONCLUSION

Intervention Mapping proved a useful tool for developing an intervention which is grounded in theory and empirical evidence. The intervention has the potential to improve adherence in breast cancer survivors but needs to be trialled before the effectiveness of the intervention can be determined.

Preferences of Individuals With Cancer for Patient-Reported Outcome Measures

PURPOSE

Symptom monitoring and management using patient-reported outcome (PRO) measures improves outcomes for individuals with cancer. The purpose of the current study was to provide a qualitative assessment of preferences of individuals with cancer for PRO measures.

PARTICIPANTS & SETTING

15 patients receiving systemic therapy at the University of Texas MD Anderson Cancer Center.

METHODOLOGIC APPROACH

Participants completed three PRO measures. Qualitative interviews were conducted, and content analysis was used to identify relevant themes.

FINDINGS

Identified themes were the importance of communicating various aspects of the disease and treatment experience to the oncology team, the importance of systematic PRO assessments, congruence among PRO questionnaires and questions clinicians ask at clinic visits, concerns about the length of PRO questionnaires, the importance of the response options available in PRO questionnaires, and willingness to complete PRO measures frequently.

IMPLICATIONS FOR NURSING

Oncology nurses are critical facilitators of the systematic use of PRO measures across the cancer care continuum.

Endocrine therapy and radiotherapy use among older women with hormone receptor-positive, clinically node-negative breast cancer

PURPOSE

To examine patterns of radiotherapy (RT) and endocrine therapy (ET) use, associations between RT omission and ET adherence, and associations among ET and RT use and disease recurrence in older women with early-stage, estrogen receptor-positive breast cancer.

METHODS

Women age 65 and older diagnosed with hormone receptor-positive, clinically node-negative breast cancer between 2005 and 2018 and who did not undergo mastectomy were included. Multinomial logistic regression was used to examine the trends in practice patterns over time and by age. Kaplan-Meier estimates were used to estimate the probability of ET discontinuation. Cox proportional hazards models were constructed to assess associations between recurrence and ET/RT.

RESULTS

Of the 484 enrolled patients, 47.9% patients underwent RT and initiated ET, 27.4% received ET alone, 10.2% received RT alone, and 13.8% patients received neither. Older patients had a higher probability of receiving ET alone or neither ET nor RT (both p < 0.001). The probability of initiating ET was greater among patients who underwent RT than those who omitted RT (p < 0.001). Regardless of RT status (RT or no RT), initiation and continuation of ET may be associated with reduced risk of recurrence.

CONCLUSION

Patients who opt for no adjuvant therapy, or who do not tolerate ET, are at increased risk of disease recurrence if they omit RT. Clinicians should consider the likelihood a patient will adhere to ET prior to recommending omission of RT.

Assessing Predictors of Tamoxifen Nonadherence in Patients with Early Breast Cancer

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

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

BACKGROUND

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

SUBJECTS AND METHODS

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

RESULTS

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

CONCLUSIONS

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

Development of health behaviour questionnaire for breast cancer women in Mainland China

Aim

To develop a questionnaire on the health behaviour of breast cancer women with adjuvant endocrine therapy and to test its reliability and validity.

Design

An instrument‐development study was applied that comprised three steps: conceptualization, item generation, content validity and field testing of the health behavior properties.

Methods

On the basis of literature review, the conceptual framework and initial items of each dimension of were designed. The questionnaire investigation was divided into two steps: pre‐experiment (group 1) and psychometrics evaluation (group 2). Correlation procedure and factor analysis were employed to rescreen the items. Reliability testing and validity testing were conducted to analyse the psychometric properties of questionnaire.

Results

Exploratory and confirmatory factor analyses yielded a five‐factor solution. Cronbach's α was 0.93, the sub‐semi‐reliability of the questionnaire was 0.79 and internal consistency coefficients was 0.70.

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.

Religion and spirituality: their role in the psychosocial adjustment to breast cancer and subsequent symptom management of adjuvant endocrine therapy

PURPOSE

Distress from being diagnosed with breast cancer can impact a woman's decision to continue taking adjuvant endocrine therapy (AET). The purpose of this study is to explore how religion and/or spirituality influence women's psychosocial adjustment to breast cancer and subsequent symptom management among women on active AET.

METHODS

Semi-structured in-depth interviews were conducted with breast cancer survivors (n = 19) from California and Texas. Interview questions prompted discussion about AET and how women adjusted to a breast cancer diagnosis and treatment with AET. Interview transcripts were analyzed with a deductive grounded theory approach, and an inductive constant comparison approach was used to identify the sources of religion and spirituality.

RESULTS

Religion supported women in their psychosocial adjustment to breast cancer by offering them a sense of purpose and meaning in life. It helped women make sense of their AET treatment as they persisted with it despite experiencing adverse side-effects. Spirituality played a prominent role in women's mental and physical wellbeing by facilitating positive and calm attitudes, which lessened women's fear during their cancer diagnosis and treatment.

CONCLUSION

We identified that religion and/or spirituality helps women with their adjustment to breast cancer and influences their continued use and management of side-effects from AET.

IMPLICATIONS FOR BREAST CANCER SURVIVORS

This study illustrates the importance of developing meaning-centered interventions that harness religion and spirituality to help women cope with AET. Our findings support the development of interventions that work to enhance AET persistence among breast cancer survivors.

Clinical practice to address tamoxifen nonadherence

The primary and secondary benefits of tamoxifen as adjuvant therapy in women with hormone-receptor-positive breast cancer are substantial: a 1% decrease in the risk of death each year for 10 years with each additional year of treatment during the first 5 years. Considerable data, however, indicate that these benefits are lost to many patients because of treatment nonadherence. Nonadherence is examined within the framework of the Common-Sense Model of Self-Regulation to describe patients' models of disease and treatment that organize their thinking and behavior, and the crucial role of the practitioner in addressing and altering these models. Common patient education and social communications about patients' hormone-receptor-positive breast cancer and tamoxifen treatment promote an acute disease paradigm in which cancer occurs within specific locations and is either present or absent. We recommend that clinicians communicate the concepts of hormone-receptor-positive breast cancer as follows: i. a non-dichotomous systemic disorder entailing a treatment goal of homeostasis and disease quiescence and ii. a disorder undetectable by currently available tests in subclinical states. Equally important, the clinician can provide a comprehensive picture of the well-documented secondary effects of tamoxifen, noting in particular the beneficial effects. Specific action plans, grounded in individual patient understanding, can be developed and reinforced, in an ongoing process that validates and integrates patient values and goals as they change over time.

Adherence status to Adjuvant Endocrine Therapy in Chinese Women with Early Breast Cancer and its influencing factors: A cross-sectional survey

OBJECTIVE

Despite the proven benefits of adjuvant endocrine therapy, adherence to oral endocrine therapy in breast cancer treatment is a substantial problem. The aim of this study was to assess adherence to adjuvant endocrine therapy by women in China for the first 5 years, and to identify its influencing factors.

METHODS

Stratified sampling method was adopted to select 1875 cases of breast cancer patients for cross-sectional telephone follow-up. Compliance to medications was assessed using the Morisky Medication Adherence Scale. Status of endocrine therapy was assessed using nine additional questions. Binomial regression was used when assessing the factors associated with persistence, multinomial regression models were used to assess factors associated with compliance.

RESULTS

Of 888 patients who started adjuvant endocrine therapy, 769(86.6%) persisted and 119 (13.4%) discontinued. 760 patients who completed Morisky Medication Adherence Scale, the compliance was 7.4% low, 42% medium, and 50.6% high. The type of medication, duration of medication and side effects had an impact both on persistence and compliance. Age, history of radiotherapy and caregivers only had an impact on persistence.

CONCLUSIONS

Medication adherence was affected by many factors. Special attention and interventions should be given to women taking tamoxifen in the 2nd to 3rd year of medication, and aromatase inhibitors in the 1st to 2nd year. Further prospective design studies are needed to explore effective measures to improve medication adherence of women with breast cancer treated by endocrine therapy.

Patient interactive digital support for women with adjuvant endocrine therapy in order to increase compliance and quality of life

PURPOSE

The primary aim of the study was to develop and investigate a patient interactive digital support (an app) for patients on adjuvant endocrine breast cancer treatment. Patient's interactive digital applications are a fast-growing area for research and development. In general, patients want more information and support with regard to their diagnosis, treatment and self-care. At the same time, the health care system has limited resources for follow-up. Our primary endpoints were usability of the app and if it added any value to the patients.

METHODS

We designed and constructed a prototype, in dialogue with patients, containing four main modules for registration of drug compliance, performed physical exercise, self-care activities, and questions on health and quality of life. The app was then tested by patients and improved further before we completed a pilot study in which 15 patients used the app for 3 months.

RESULTS

Patients perceived the app easy to use with a very high median system usability score of 88.8, range 30-100. The 15 women registered in total 4251 times, range 118 to 372. The majority of registrations concerned compliance (adherence to treatment) and physical exercise.

CONCLUSION

The app was perceived easy to use and of support in every-day life of breast cancer survivors. How to best integrate electronically collected patient reported outcome measures in clinical routine needs to be further studied, and future research will show if it will be cost-effective in terms of better health outcome and less resource use.

Symptom Care at Home: A Comprehensive and Pragmatic PRO System Approach to Improve Cancer Symptom Care

INTRODUCTION

There is growing recognition that systematically obtaining the patient's perspective on their health experience, using patient-reported outcomes (PRO), can be used to improve patient care in real time. Few PRO systems are designed to monitor and provide symptom management support between visits. Patients are instructed to contact providers between visits with their concerns, but they rarely do, leaving patients to cope with symptoms alone at home. We developed and tested an automated system, Symptom Care at Home (SCH), to address this gap in tracking and responding to PRO data in-between clinic visits. The purpose of this paper is to describe SCH as an example of a comprehensive PRO system that addresses unmet need for symptom support outside the clinic.

METHODS FOR PRO SCORE INTERPRETATION

SCH uses pragmatic, single-item measures for assessing symptoms, which are commonly used and readily interpretable for both patients and providers. We established alerting values for PRO symptom data, which was particularly important for conserving oncology providers' time in responding to daily PRO data.

METHODS FOR DEVELOPING RECOMMENDATIONS FOR ACTING ON PRO RESULTS

The SCH system provides automated, just-in-time self-management coaching tailored to the specific symptom pattern and severity levels reported in the daily call. In addition, the SCH system includes a provider decision support system for follow-up symptom assessment and intervention strategies.

DISCUSSION

SCH provides PRO monitoring, tailored automated self-management coaching, and alerts the oncology team of poorly controlled symptoms with a provider dashboard that includes evidence-based decision support for follow-up to improve individual patients' symptom care. We particularly emphasize our process for PRO selection, rationale for determining alerting thresholds, and the design of the provider dashboard and decision support. Currently, we are in the process of updating the SCH system, developing both web-based and app versions in addition to interactive voice response phone access and integrating the SCH system in the electronic health record.

The Effects of Pharmacological and Non-Pharmacological Interventions on Symptom Management and Quality of Life among Breast Cancer Survivors Undergoing Adjuvant Endocrine Therapy: A Systematic Review

Breast cancer survivors need to undergo adjuvant endocrine therapy after completion of curative treatments to prevent disease recurrence. These individuals often experience symptoms which are detrimental to their quality of life (QOL). Implementation of interventions for effective symptom management among these survivors is warranted. This review provides an overview of studies on the effectiveness of the previously developed interventions for breast cancer survivors undergoing adjuvant endocrine therapy on symptom alleviation and enhancement of QOL or health-related QOL (HRQOL). Five electronic databases were employed in the literature search. Study selection, data extraction and critical appraisal of the included studies were conducted by three authors independently. Twenty-four studies were included. Both pharmacological and non-pharmacological interventions are effective in addressing the symptoms associated with adjuvant endocrine therapy among the breast cancer survivors, and in improving their QOL, although discrepancies were noted between the studies in terms of the significance of these effects. Pharmacological and non-pharmacological interventions can be effective for symptom management among breast cancer survivors. Their implementation is recommended for effective survivorship care for these individuals. Further research on intervention development for breast cancer survivors is recommended to provide further evidence for the utility of the explored interventions in survivorship care for these patients.

Factors influencing medication-taking behaviour with adjuvant endocrine therapy in women with breast cancer: A qualitative systematic review

AIMS

To explore the experience and feelings associated with the endocrine therapy treatment trajectory in women with breast cancer and what affects medication taking behaviour.

DESIGN

Qualitative systematic review.

DATA SOURCES

Qualitative studies were extracted from PubMed, EMBASE, CINAHL, PsycINFO from inception of each database until February 2019.

REVIEW METHODS

The systematic search method SPIDER (sample, phenomenon of interest, design, evaluation, research type) was used. Thematic synthesis of the qualitative data was used.

RESULTS

A total of 478 were identified in the initial search. Only 17 articles met inclusion criteria and were included in this review. Five analytical themes and 17 descriptive subthemes were identified.

CONCLUSIONS

The systematic review highlights knowledge, balancing the scales, self-efficacy and support influence medication taking behaviour to women with breast cancer.

IMPACT

The medication taking behaviour of breast cancer women can be classified into four types: acceptance/persistence, bearing/suffering, hesitation/adjustment, refusing/abandoning. The four types can switch from one to another. Medication taking behaviour is affected by knowledge, balancing the scales, self-efficacy, and support. The medical institutions, communities, and families can gain knowledge of the treatment experiences of women to better understand medication taking behaviour and those at risk for non-adherence. Women wanted different types and amounts of information. Healthcare providers should be aware of patient preferences and take targeted interventions to help them receive treatment.

Factors associated with endocrine therapy adherence among post-menopausal women treated for early-stage breast cancer in Ontario, Canada

PURPOSE

Adherence to adjuvant endocrine therapy among post-menopausal breast cancer patients is an important survivorship care issue. We explored factors associated with endocrine therapy adherence and survival in a large real-world population-based study.

METHODS

We used health administrative databases to follow women (aged ≥ 66 years) who were diagnosed with breast cancer and started on adjuvant endocrine therapy from 2005 to 2010. Adherence was measured by medical possession ratio (MPR) and characterized as low (< 39% MPR), intermediate (40-79% MPR), or high (≥ 80% MPR) over a 5-year period. We investigated factors associated with adherence using a multinomial logistic regression model. Factors associated with all-cause mortality (5 years after starting endocrine therapy) were investigated using a multivariable Cox proportional hazards model.

RESULTS

We identified 5692 eligible patients starting adjuvant endocrine therapy who had low, intermediate, and high adherence rates of 13% (n = 749), 13% (n = 733), and 74% (n = 4210), respectively. Lower rates of adherence were associated with increased age [low vs. high adherence: odds ratio (OR) 1.03, 95% CI 1.02-1.05 (per year); intermediate vs. high adherence: OR 1.02, 95% CI 1.01-1.04 (per year)]. High adherence was associated with previous use of adjuvant chemotherapy (low versus high adherence OR 0.42, 95% CI 0.30-0.59) and short-term follow-up with a medical oncologist within 4 months of starting endocrine therapy (low versus high adherence OR 0.83, 95% CI 0.69-0.99). Unadjusted analysis showed increased survival among patients with high endocrine therapy adherence. However, an independent association was no longer clearly detected after controlling for confounders.

CONCLUSION

Interventions to improve adjuvant endocrine therapy adherence are warranted. Non-adherence may be a more significant issue among elderly patients. Short-term follow-up visit by a patient's medical oncologist after starting endocrine therapy may help to improve compliance.

Impact of Older Age and Comorbidity on Locoregional and Distant Breast Cancer Recurrence: A Large Population-Based Study

BACKGROUND

Studies have demonstrated worse breast cancer-specific mortality with older age, despite an increasing risk of dying from other causes due to comorbidity (competing mortality). However, findings on the association between older age and recurrence risk are inconsistent. The aim of this study was to assess incidences of locoregional and distant recurrence by age, taking competing mortality into account.

MATERIALS AND METHODS

Patients surgically treated for nonmetastasized breast cancer between 2003 and 2009 were selected from The Netherlands Cancer Registry. Cumulative incidences of recurrence were calculated considering death without distant recurrence as competing event. Fine and Gray analyses were performed to characterize the impact of age (70-74 [reference group], 75-79, and ≥80 years) on recurrence risk.

RESULTS

A total of 18,419 patients were included. Nine-year cumulative incidences of locoregional recurrence were 2.5%, 3.1%, and 2.9% in patients aged 70-74, 75-79, and ≥80 years, and 9-year cumulative incidences of distant recurrence were 10.9%, 15.9%, and 12.7%, respectively. After adjustment for tumor and treatment characteristics, age was not associated with locoregional recurrence risk. For distant recurrence, patients aged 75-79 years remained at higher risk after adjustment for tumor and treatment characteristics (75-79 years subdistribution hazard ratio [sHR], 1.25; 95% confidence interval [CI], 1.11-1.41; ≥80 years sHR, 1.03; 95% CI, 0.91-1.17).

CONCLUSION

Patients aged 75-79 years had a higher risk of distant recurrence than patients aged 70-74 years, despite the higher competing mortality. Individualizing treatment by using prediction tools that include competing mortality could improve outcome for older patients with breast cancer.

IMPLICATIONS FOR PRACTICE

In this population-based study of 18,419 surgically treated patients aged 70 years or older, patients aged 75-79 years were at higher risk of distant recurrence than were patients aged 70-74 years. This finding suggests that patients in this age category are undertreated. In contrast, it was also demonstrated that the risk of dying without a recurrence strongly increases with age, and patients with a high competing mortality risk are easily overtreated. To identify older patients who may benefit from more treatment, clinicians should therefore take competing mortality risk into account. Prediction tools could facilitate this and thereby improve treatment strategy.

Effectiveness of radiotherapy after breast-conserving surgery in older patients with T1-2N0 breast cancer

Purpose

In the Netherlands, radiotherapy after breast-conserving surgery (BCS) is omitted in up to 30% of patients aged ≥ 75 years. Although omission of radiotherapy is considered an option for older women treated with endocrine treatment, the majority of these patients do not receive systemic treatment following Dutch treatment guidelines. Therefore, the aim of this study was to evaluate the effect of omission of radiotherapy on locoregional recurrence risk in this patient population.

Methods

Patients aged ≥ 75 years undergone BCS for T1-2N0 breast cancer diagnosed between 2003 and 2009 were selected from the Netherlands Cancer Registry. To minimize confounding by indication, hospital variation was used to assess the impact of radiotherapy-use on locoregional recurrence risk using cox proportional hazards regression. Hazards ratios with 95% confidence interval (CI) were estimated.

Results

Overall, 2390 patients were included. Of the patients with hormone receptor-positive breast cancer, 39.3% received endocrine treatment. Five-year incidences of locoregional recurrence were 1.9%, 2.8%, and 3.0% in patients treated at hospitals with higher (average radiotherapy-use 96.0%), moderate (88.0%), and lower radiotherapy-use (72.2%) respectively, and nine-year incidences were 2.2%, 3.1%, and 3.2% respectively. Adjusted hazard ratios were 1.46 (95% CI 0.77–2.78) and 1.50 (95% CI 0.79–2.85) for patients treated at hospitals with moderate and lower radiotherapy-use, compared to patient treated at hospitals with higher radiotherapy-use.

Conclusions

Despite endocrine treatment in only 39.3%, locoregional recurrence risk was low, even in patients treated at hospitals with lower radiotherapy-use. This provides reasonable grounds to consider omission of radiotherapy in patients aged ≥ 75 years with T1-2N0 breast cancer.

Electronic supplementary material

The online version of this article (10.1007/s10549-019-05412-8) contains supplementary material, which is available to authorized users.

Patient-reported Adherence to Adjuvant Aromatase Inhibitor Therapy Using the Morisky Medication Adherence Scale: An Evaluation of Predictors

OBJECTIVES

Endocrine therapy is part of standard adjuvant therapy for patients with hormone receptor-positive breast cancer and has been shown to improve recurrence-free and overall survival. However, adherence to endocrine therapy is suboptimal and is difficult to measure. In this study we evaluate the feasibility of using the Morisky Medication Adherence Scale (MMAS) to assess patient adherence to aromatase inhibitor (AI) therapy.

METHODS

Patients with stage 1 to 3, hormone receptor-positive breast cancer receiving adjuvant AI therapy were prospectively enrolled on an Institutional Review Board approved protocol. The MMAS questionnaire was administered to each patient and adherence was measured. Information on duration of AI therapy, patient and tumor characteristics, and treatment was collected. A multivariable logit model approach was utilized to evaluate potential barriers to adherence.

RESULTS

Between 2011 and 2014, 100 patients were enrolled. The distribution of adherence levels was 13% low, 37% medium, and 50% high. High adherence was reported more frequently in white women (58%), patients with stage 2 and 3 disease (54%), and patients who did not receive chemotherapy (62%). Multivariable analysis demonstrated that higher adherence was more likely in white women compared with African American women (estimated odds ratio=2.8).

CONCLUSIONS

Using the MMAS, only 50% of women with stage 1 to 3 breast cancer reported high adherence to AI therapy, consistent with other reports showing suboptimal adherence to adjuvant endocrine therapy. The MMAS allows for the rapid assessment of adherence to oral adjuvant endocrine therapy and is valuable in a busy clinical setting.