Endocrine therapy initiation, discontinuation and adherence and breast imaging among 21-gene recurrence score assay-eligible women under age 65

Abstract

BackgroundAside from chemotherapy utilization, limited data are available on the relationship between gene expression profiling (GEP) testing and breast cancer care. We assessed the relationship between GEP testing and additional variables and the outcomes of endocrine therapy initiation, discontinuation and adherence, and breast imaging exams in women under age 65 years.MethodsData from five state cancer registries were linked with claims data and GEP results. We assessed variables associated with survivorship care outcomes in an incident cohort of 5014 commercially insured women under age 65 years, newly diagnosed with stage I or II hormone-receptor-positive, human epidermal growth factor receptor 2 (HER2) non-positive breast cancer from 2006 to 2010.ResultsAmong tested women, those with high Oncotype DX® Breast Recurrence Score® (RS) were significantly less likely to initiate endocrine therapy than women with low RS tumors (OR 0.40 (95% CI 0.20 to 0.81); P = 0.01). Among all test-eligible women, receipt of Oncotype DX testing was associated with a greater likelihood of endocrine therapy initiation (OR 2.48 (95% CI 2.03 to 3.04); P <0.0001). The odds of initiation were also significantly higher for tested vs. untested women among women who did not initiate chemotherapy within six months of diagnosis (OR 3.25 (95% CI 2.53 to 4.16)), with no effect in women who received chemotherapy. Discontinuation and adherence and breast imaging exams were unrelated to tested status or RS.ConclusionsLower endocrine therapy initiation rates among women with high RS tumors and among untested women not receiving chemotherapy are concerning, given its established efficacy. Additional research is needed to suggest mechanisms to close this gap.

Preventing metastatic recurrence in low-risk ER/PR + breast cancer patients—a retrospective clinical study exploring the evolving challenge of persistence with adjuvant endocrine therapy

“…We hypothesized that if persistence with medication is motivated in part by an understanding of risk, the 10 years recurrence risk as estimated by Oncotype-DX may be influential. Others have shown the influence of recurrence score on initiation of endocrine therapy [46] however did not find Fig. 4 Clinical management of bothersome symptoms attributed to endocrine therapy in persistent versus non-persistent patients.…”

“…We hypothesized that if persistence with medication is motivated in part by an understanding of risk, the 10 years recurrence risk as estimated by Oncotype-DX may be influential. Others have shown the influence of recurrence score on initiation of endocrine therapy [ 46 ] however did not find a significant effect on early discontinuation. In contrast, we found that patients who persisted with endocrine therapy despite bothersome side effects had significantly higher Oncotype Scores compared to patients who discontinued early, although the difference was small (15.9 vs. 13.7, p = 0.028).…”

“…Lower tumor stage and negative lymph node status are also associated with non-persistence [ 19 , 44 , 45 ]. There are limited data available on the influence of genetic test results [ 46 ], although this may be an area of increasing importance.…”

The impact of gene expression profile testing on confidence in chemotherapy decisions and prognostic expectations

“…[22] Paradoxically, evidence suggests that inaccurate risk perception may be associated with poor treatment adherence and surveillance decisions in survivorship. [23] Following publication of the findings of the TAILORx study, future research should examine the role of GEP testing and risk perceptions on survivorship and surveillance outcomes.…”

Patient experiences and views on pharmaceutical care during adjuvant endocrine therapy for breast cancer: A qualitative study

“…Between 4% and 30% of women with hormone receptor (HR)‐positive breast cancer who completed primary treatment of early‐stage breast cancer (EBC) do not initiate the follow‐up long‐term adjuvant endocrine therapy (AET) (Berkowitz et al, 2021 ; Kroenke et al, 2018 ; Neugut et al, 2012 ; O'Neill et al, 2017 ), and 15–43% are non‐adherent (i.e., do not take medication as prescribed) (Berkowitz et al, 2021 ; Cavazza et al, 2020 ; Font et al, 2019 ; Lailler et al, 2021 ; Lambert‐Côté et al, 2020 ; Makubate et al, 2013 ; Mislang et al, 2017 ; Murphy et al, 2012 ). AET is used in patients with oestrogen receptor (ER)‐positive EBC for at least 5 years in order to prevent recurrence and reduce the mortality (Cardoso et al, 2019 ; Early Breast Cancer Trialists' Collaborative Group, 2011 ) and comprises the (sequential) use of the selective ER modulator (SERM) tamoxifen and aromatase inhibitors (AIs) like anastrozole, exemestane and letrozole (Burstein et al, 2019 ; Cardoso et al, 2019 ; Parisi et al, 2020 ).…”