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

Abstract

Purpose Adjuvant endocrine treatment is essential for treating luminal subtypes of breast cancer, which constitute 75% of all breast malignancies. However, the detrimental side effects of treatment make it difficult for many patients to complete the guideline-required treatment. Such non-adherence may jeopardize the lifesaving ability of anti-estrogen therapy. In this systematic review, we aimed to assess the consequences of non-adherence and non-persistence from available studies meeting strict statistical and clinical criteria. Methods A systematic literature search was performed using several databases, yielding identification of 2,026 studies. After strict selection, 14 studies were eligible for systematic review. The review included studies that examined endocrine treatment non-adherence (patients not taking treatment as prescribed) or non-persistence (patients stopping treatment prematurely), in terms of the effects on event-free survival or overall survival among women with non-metastatic breast cancer. Results We identified 10 studies measuring the effects of endocrine treatment non-adherence and non-persistence on event-free survival. Of these studies, seven showed significantly poorer survival for the non-adherent or non-persistent patient groups, with hazard ratios (HRs) ranging from 1.39 (95% CI, 1.07 to 1.53) to 2.44 (95% CI, 1.89 to 3.14). We identified nine studies measuring the effects of endocrine treatment non-adherence and non-persistence on overall survival. Of these studies, seven demonstrated significantly reduced overall survival in the groups with non-adherence and non-persistence, with HRs ranging from 1.26 (95% CI, 1.11 to 1.43) to 2.18 (95% CI, 1.99 to 2.39). Conclusion The present systematic review demonstrates that non-adherence and non-persistence to endocrine treatment negatively affect event-free and overall survival. Improved follow-up, with focus on adherence and persistence, is vital for improving health outcomes among patients with non-metastatic breast cancer.

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

“…To the best of our knowledge, this is the first study to investigate the impacts of Reishimmune-S on survivors of BC receiving ET. As adverse reactions to treatment regimens, such as ET, may impair adherence, 39 - 41 BC survival outcomes, 17 the development of non-pharmacological interventions for treatment-related fatigue in this population represents an important clinical challenge. Reishimmune-S, a recombinant GMI product, may hold promise for improving fatigue management and cognitive function as well as alleviating sleep disturbance in this population.…”

“… 8 - 10 By disrupting neuro-immune-endocrine (NIE) networks, 11 , 12 ET may contribute to fatigue, 13 sleep disruption, 14 and inflammation around the joints and muscles, 15 leading to impaired quality of life (QoL) and affecting treatment adherence. 16 As nonadherence to adjuvant ET is correlated with impaired cancer-specific survival, 17 proper management of these adverse effects is vital for improving the health outcomes of BC survivors. However, only 44% of patients with ET-related adverse effects use medications to overcome them.…”

“…However, only 44% of patients with ET-related adverse effects use medications to overcome them. 17 Furthermore, evidence-based pharmacologic treatment options are still limited for ET-related adverse effects other than pain and insomnia. 16 …”

Preexisting Diabetes and Breast Cancer Treatment Among Low-Income Women

“…All of these studies examined adjuvant therapies as binary variables (yes or no) with no focus on whether patients actually completed radiotherapy and chemotherapy and whether they adhered to and persisted in endocrine therapy, which are also important contributors to breast cancer prognosis. [25][26][27] To fill these knowledge gaps, we comprehensively examined the associations of preexisting diabetes with utilization, timely initiation, adherence, persistence and continuation, and/or completion of adjuvant therapies for breast cancer among Medicaid-insured women. Understanding the factors influencing cancer treatment among Medicaid beneficiaries is critical for interventions to improve breast cancer care in this medically vulnerable and underserved population, thereby reducing socioeconomic disparities in breast cancer.…”

“…Additionally, prior studies assessed only 1 or 2 types of therapies, which only constituted part of a cancer treatment plan. All of these studies examined adjuvant therapies as binary variables (yes or no) with no focus on whether patients actually completed radiotherapy and chemotherapy and whether they adhered to and persisted in endocrine therapy, which are also important contributors to breast cancer prognosis …”