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

Christine Brezden-Masley,Kelly E Fathers,Megan E Coombes,Cloris Xue,Katarzyna J Jerzak,Behin Pourmirza

doi:10.1007/s10549-020-05976-w

Abstract

PurposeWe sought to expand the currently limited, Canadian, population-based data on the characteristics, treatment pathways, and health care costs according to stage in patients with human epidermal growth factor receptor-2 positive (HER2+) breast cancer (BC).MethodsWe extracted data from the publicly funded health care system in Ontario. Baseline characteristics, treatment patterns, and health care costs were descriptively compared by cancer stage (I–III vs. IV) for adult women diagnosed with invasive HER2+ BC between 2012 and 2016. Resource use was multiplied by unit costs for publicly funded health care services to calculate costs.ResultsOverall, 4535 patients with stage I–III and 354 with stage IV HER2+ BC were identified. Most patients with stage I–III disease were treated with surgery (4372, 96.4%), with the majority having a lumpectomy, and 3521 (77.6%) received radiation. Neoadjuvant (NAT) and adjuvant (AT) systemic treatment rates were 20.1% (n = 920) and 88.8% (n = 3065), respectively. Systemic treatment was received by 311 patients (87.9%) with metastatic HER2+ BC, 264 of whom (84.9%) received trastuzumab. Annual health care costs per patient were nearly 3 times higher for stage IV vs. stage I–III HER2+ BC.ConclusionPer-patient annual costs were substantially higher for women with metastatic HER2+ BC, despite less frequent exposure to surgery and radiation compared to those with early stage disease. Increasing NAT rates in early stage disease represent a critical opportunity to prevent recurrence and reduce the costs associated with treating metastatic HER2+ BC.

Highlights

Overall, human epidermal growth factor receptor-2 (HER2) positivity is seen in approximately 15–20% of breast carcinomas [1]
HER2-targeted therapy has revolutionized the treatment of HER2+ breast cancer (BC), and its use in the curative setting has changed the natural course of the disease, achieving outcomes similar to those of patients with HER2-negative disease for a historically poor prognosis subpopulation [2]
The only nearly comparable study of resource utilization in Ontario was that reported by Mittmann et al [31] in which incident cases of BC diagnosed from 2005-2009 had an average 2-year cost of $29,938, $46,893, $65,369, and $66,627 in stage I, II, III and IV, respectively. This is in contrast to our more contemporary and HER2+ -subtyped cohort in which we report an average annual cost of $54,852 and $159,348 in patients with stage I–III and stage IV disease, respectively

Summary

Introduction

Human epidermal growth factor receptor-2 (HER2) positivity is seen in approximately 15–20% of breast carcinomas [1]. HER2-targeted therapy has revolutionized the treatment of HER2+ breast cancer (BC), and its use in the curative setting has changed the natural course of the disease, achieving outcomes similar to those of patients with HER2-negative disease for a historically poor prognosis subpopulation [2]. Chronic management has become a clinical reality, with trial and epidemiological data proving that HER2-targeted therapy prolongs survival [2, 3]. Trastuzumab is the earliest and most extensively studied HER2-targeted therapy in BC, and its efficacy has been demonstrated in both early and metastatic disease [2,. In patients with HER2+ breast cancer that express hormone receptors (HR+), standard HER2-targeted therapy with chemotherapy remains the most common approach upfront, with substitution of chemotherapy for endocrine therapy in the maintenance phase of treatment [5]

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Results

Discussion

Conclusion