A European, Observational Study of Endocrine Therapy Administration in Patients With an Initial Diagnosis of Hormone Receptor-Positive Advanced Breast Cancer

Abstract

In this observational study we estimated the proportion of postmenopausal breast cancer patients initially diagnosed with hormone receptor (HR)-positive locally advanced or metastatic breast cancer (LA/MBC), using data from 6 European cancer registries (n [ 244,268 with known HR status and disease stage). Approximately 19,002 patients (7.8%) received an initial diagnosis of HR-positive LA/MBC; 74.5% (n [ 14,157) of these received subsequent endocrine therapy as per guideline recommendations. Background: Despite guideline recommendations, reports suggest that a proportion of patients with hormone receptor (HR)-positive locally advanced or metastatic breast cancer (LA/MBC) might not receive endocrine therapy. The aims of this study were to estimate the proportion of postmenopausal patients with an initial (primary) diagnosis of HR-positive LA/MBC in Europe, and to assess the administration of endocrine treatment in these patients. Materials and Methods: Fourteen national and regional cancer registries across Europe were invited to participate in this observational study. Six registries each provided anonymized clinical information on > 5000 postmenopausal women with breast cancer diagnosed between January 2000 and December 2014, including age at diagnosis, estrogen and/or progesterone receptor status, disease stage, and receipt of endocrine therapy. The proportion of patients with an initial diagnosis of HR-positive LA/MBC and, of these, the proportion who received endocrine therapy, was calculated. Results: Registries from Belgium, England, Ireland, Norway, The Netherlands, and Munich, Germany provided data. In total, 316,680 postmenopausal women were diagnosed with breast cancer, including 244,268 with known HR status and disease stage. Of these patients, 19,002 (7.8%) had a primary diagnosis of HR-positive LA/MBC. This proportion ranged from 5.4% (N ¼ 4484) in England to 12.7% (N ¼ 4085) in Germany. Most of these patients (n ¼ 14,157; 74.5%) received endocrine treatment, ranging from 55.5% (n ¼ 445) in Clinical Breast Cancer Month 2017 -1 Norway to 88.1% (n ¼ 443) in Belgium. Conclusion: These results indicate that a sizeable proportion of postmenopausal patients in Europe received a primary diagnosis of HR-positive LA/MBC, and that almost threequarters received subsequent endocrine therapy as per guideline recommendations.

A population-based comparison of treatment patterns, resource utilization, and costs by cancer stage for Ontario patients with hormone receptor-positive/HER2-negative breast cancer

“…The incidence of HR+/HER2− BC among all BC subtypes in our study was 64.8%, with 3.7% diagnosed as stage IV. These incidences are in line with those observed in a European registry analysis [23] and a US populationbased case-control study [24]. Interestingly, the proportion of patients with ER positive tumors was higher in our cohort than others (99% versus 86%) [23,24].…”

“…These incidences are in line with those observed in a European registry analysis [23] and a US populationbased case-control study [24]. Interestingly, the proportion of patients with ER positive tumors was higher in our cohort than others (99% versus 86%) [23,24]. The majority of patients with stage I-III HR+/HER2− BC in our study had favorable prognostic features such as tumor size < 2 cm (53%), lymph node negative status (62%), and well to moderately differentiated tumor pathology (75%).…”

“…Systemic treatment in the de novo metastatic setting was high (93.2%); however, only 66.7% overall received endocrine therapy; a rate lower than that reported in comparable cohorts [23,43]. Since public funding for endocrine therapy does not cover all patients for whom it is recommended (i.e., those < 65 years of age) we were not able to wholly assess exposure rates using administrative claims data alone.…”

Cost-Effectiveness Analysis of Fulvestrant 500 mg in Endocrine Therapy-Naïve Postmenopausal Women with Hormone Receptor-Positive Advanced Breast Cancer in the UK

“…In the UK, approximately 13–21% of patients with breast cancer receive a late-stage diagnosis (stage III or IV), and 6–7% of patients have metastases at diagnosis [2]; a large proportion of these patients are likely to be endocrine therapy-naïve. However, one European observational study found that approximately one-quarter of postmenopausal patients with an initial diagnosis of HR+ locally advanced or metastatic disease did not receive subsequent endocrine therapy [4].…”

Endocrine therapy in the years following a diagnosis of breast cancer: A proof of concept study using the primary care prescription database linked to cancer registration data

“…Most women diagnosed with oestrogen receptor positive (ER+ve) breast cancer in England are prescribed endocrine therapy (ET). ET decreases recurrence and increases survival [1] and is the current standard treatment for patients with ER+ve disease in both early and metastatic breast cancer [2]. Adherence to ET was reported to be between 40% and 70% over a five year treatment period [3,4].…”