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

Neoadjuvant chemotherapy for triple-negative and Her2 +ve breast cancer: striving for the standard of care

PURPOSE

Neoadjuvant chemotherapy (NAC) for triple-negative (TN) and Her2-positive (HER2) breast cancers is supported by international guidelines as it can decrease extent of surgery, provide prognostic information, and allow response-driven adjuvant therapies. Our goal was to describe practice patterns for patients with TN and HER2-positive breast cancer and identify the factors associated with the receipt of NAC versus surgery as initial treatment.

METHODS

A retrospective population-based cohort study of adult women diagnosed with stage I-III TN or HER2-positive breast cancer (2012-2020) in Ontario was completed using linked administrative datasets. The primary outcome was NAC as first treatment. The association between NAC and patient, tumor, and practice-related factors was examined using multivariable logistic regression models.

RESULTS

Of 14,653 patients included, 23.9% (n = 3500) underwent NAC as first treatment. Patients who underwent NAC were more likely to be younger and have larger tumors, node-positive disease, and stage 3 disease. Of patients who underwent surgery first, 8.8% were seen by a medical oncologist prior to surgery. On multivariable analysis, increasing tumor size (T2 vs T1/T0: 2.75 (2.31-3.28)) and node-positive (N1 vs N0: OR 3.54 (2.92-4.30)) disease were both associated increased odds of receiving NAC.

CONCLUSION

A considerable proportion of patients with TN and HER2-positive breast cancer do not receive NAC as first treatment. Of those, most were not assessed by both a surgeon and medical oncologist prior to initiating therapy. This points toward potential gaps in multidisciplinary assessment and disparities in receipt of guideline-concordant care.

Direct and Indirect Costs of Breast Cancer and Associated Implications: A Systematic Review

INTRODUCTION

Breast cancer is currently the leading cause of global cancer incidence. Breast cancer has negative consequences for society and economies internationally due to the high burden of disease which includes adverse epidemiological and economic implications. Our aim is to systematically review the estimated economic burden of breast cancer in the United States (US), Canada, Australia, and Western Europe (United Kingdom, France, Germany, Spain, Italy, Norway, Sweden, Denmark, Netherlands, and Switzerland), with an objective of discussing the policy and practice implications of our results.

METHODS

We included English-language published studies with cost as a focal point using a primary data source to inform resource usage of women with breast cancer. We focussed on studies published since 2017, but with reported costs since 2012. A systematic search conducted on 25 January 2023 identified studies relating to the economic burden of breast cancer in the countries of interest. MEDLINE, Embase, and EconLit databases were searched via Ovid. Study quality was assessed based on three aspects: (1) validity of cost findings; (2) completeness of direct cost findings; and (3) completeness of indirect cost findings. We grouped costs based on country, cancer stage (early compared to metastatic), and four resource categories: healthcare/medical, pharmaceutical drugs, diagnosis, and indirect costs. Costs were standardized to the year 2022 in US (US$2022) and International (Int$2022) dollars.

RESULTS

Fifty-three studies were included. Studies in the US (n = 19) and Canada (n = 9) were the majority (53%), followed by Western European countries (42%). Healthcare/medical costs were the focus for the majority (89%), followed by pharmaceutical drugs (25%), then diagnosis (17%) and indirect (17%) costs. Thirty-six (68%) included early-stage cancer costs, 17 (32%) included metastatic cancer costs, with 23% reporting costs across these cancer stages. No identified study explicitly compared costs across countries. Across cost categories, cost ranges tended to be higher in the US than any other country. Metastatic breast cancer was associated with higher costs than earlier-stage cancer. When indirect costs were accounted for, particularly in terms of productivity loss, they tended to be higher than any other estimated direct cost (e.g., diagnosis, drug, and other medical costs).

CONCLUSION

There was substantial heterogeneity both within and across countries for the identified studies' designs and estimated costs. Despite this, current empirical literature suggests that costs associated with early initiation of treatment could be offset against potentially avoiding or reducing the overall economic burden of later-stage and more severe breast cancer. Larger scale, national, economic burden studies are needed, to be updated regularly to ensure there is an ongoing and evolving perspective of the economic burden of conditions such as breast cancer to inform policy and practice.

Long-term Survival Among Patients With De Novo Human Epidermal Growth Receptor 2-Positive Metastatic Breast Cancer in Manitoba

OBJECTIVES

Although metastatic breast cancer (MBC) is considered incurable, human epidermal growth receptor 2 (HER2)-directed therapy has improved outcomes significantly, with some patients experiencing durable responses to treatment. The aim of this study was to identify potential predictors of long-term survival (LTS) among patients with de novo HER2-positive MBC who received HER2-directed treatment.

METHODS

Eligible patients from 2008 to 2018 were identified using the Manitoba Cancer Registry. LTS was defined as survival ≥5 years from the time of diagnosis. Univariate logistic regression models were performed to assess variables of clinical interest and the odds of LTS. Overall survival (OS) was defined as the time from diagnosis of MBC to death of any cause. OS was estimated using the Kaplan-Meier method with log-rank comparative analyses as a univariate analysis. A Cox proportional hazards model was used for OS estimates in a univariate analysis.

RESULTS

A total of 62 patients were diagnosed with de novo HER2-positive MBC and received HER2-directed therapy. Eighteen (29%) achieved LTS. The median OS of the whole cohort was 50.2 months (95% CI: 28.6-not reached). Radiographic response to first-line treatment was associated with LTS; complete and partial responses were both associated with higher odds of LTS (odds ratio: 28.33 [95% CI: 2.47-4006.71, P = 0.0043] and odds ratio: 7.80 [95% CI: 0.7317-1072.00, P = 0.0972], respectively). The best radiographic response was associated with improved OS.

CONCLUSIONS

Radiographic response to first-line HER2-directed therapy is a predictor for LTS in patients with de novo HER2-positive MBC. Larger studies are needed to identify patients who can safely discontinue HER2-targeted therapy.