Moving beyond the stage: how characteristics at diagnosis dictate treatment and treatment-related quality of life year losses for women with early stage invasive breast cancer

ABSTRACT

Background:Although evaluations of breast cancer screening programs frequently estimate quality-adjusted life-year (QALY) losses by stage, other breast cancer characteristics influence treatment and vary by mode of detection – i.e. whether the cancer is detected through screening (screen-detected), between screening rounds (interval-detected) or outside screening (community-detected). Here, we estimate the association between early-stage invasive breast cancer (ESIBC) characteristics and treatment-related QALY losses.

Methods:Using clinicopathological and treatment information from 675 women managed for ESIBC, we estimated the average five-year treatment-related QALY loss by detection group. We then used regression analysis to estimate the extent to which known cancer characteristics and the detection mode, are associated with treatment and treatment-related QALY losses.

Results:Community-detected cancers had the largest QALY loss (0.76 QALYs [95% CI 0.73;0.80]), followed by interval-detected cancers (0.75 QALYs [95% CI 0.68;0.82]) and screen-detected cancers (0.69 QALYs [95%CI 0.67;0.71]). Adverse prognostic factors more common in community-detected and interval-detected breast cancers (large tumours, lymph node involvement, high grade) were largely associated with QALY losses from mastectomies and chemotherapy. Receptor-positive subtypes, more common in screen-detected cancers, were associated with QALY losses related to endocrine therapy.

Conclusions:The associations between ESIBC characteristics and treatment-related QALY losses should be considered when evaluating breast cancer screening and treatment strategies.

KEYWORDS:

• Breast cancer
• quality of life
• utility weights
• cost-effectiveness analysis

Acknowledgments

We would like to thank Claire Noonan, Kerry Shanahan, Lisa Sheeran and Susan Thomas in their assistance with reviewing health state utility values.

Authors’ contributions

KS and DP were responsible for the conceptualisation of the study. KS, DP, BM and CN developed the analytical framework. AP performed initial data extraction and cleaning. KS conducted the data analysis. HB and KS facilitated utility review by expert panel. All authors critically revised the final manuscript.

Availability of data and material

Data is available on application to the Royal Women’s hospital and the Victorian Cancer Registry.

Consent for publication

Not applicable.

Declaration of interest

KS occasionally works on a contract basis for consulting companies that have clients in the pharmaceutical industry, but does not directly receive funding from industry. KC has received equipment and a funding contribution for an unrelated trial from Roche Molecular Systems and Ventana Inc USA. However, neither KC or her institution (Cancer Council NSW) received direct funding from industry for this trial or any other project. All other authors have no declarations of interest or otherwise to disclose.

Reviewers disclosure

Peer reviewers on this manuscript have no relevant financial relationships or otherwise to disclose.

Ethics approval and consent to participate

This project was approved by the Cancer Council Victoria Human Research Ethics Committee (HREC 1515).

Supplementary material

Supplemental data for this article can be accessed here.

Additional information

Funding

This work was funded by the Cancer Australia Priority-driven Collaborative Cancer Research Scheme (project grant 1066771).