Oncologists’ influence on receipt of adjuvant chemotherapy: does it matter whom you see for treatment of curable breast cancer?

• Type of Material: Article
• Authors: Steven J. Katz, University of Michigan Medical School; Sarah T. Hawley, University of Michigan Medical School; Irina Bondarenko, University of Michigan School of Public Health; Reshma Jagsi, University of Michigan Medical School; Kevin Ward, Emory University; Timothy P. Hofer, University of Michigan Medical School; Allison W. Kurian, Stanford University
• Language: English
• Date: 2017-10-01
• Publisher: Springer (part of Springer Nature): Springer Open Choice Hybrid Journals
• Publication Version: Author Accepted Manuscript (After Peer Review)
• Copyright Statement: © 2017, Springer Science+Business Media, LLC.
• Final Published Version (URL): http://dx.doi.org/10.1007/s10549-017-4377-3
• Title of Journal or Parent Work: Breast Cancer Research and Treatment
• ISSN: 0167-6806
• Volume: 165
• Issue: 3
• Start Page: 751
• End Page: 756
• Grant/Funding Information: The collection of cancer incidence data in Georgia was supported by contract HHSN261201300015I, Task Order HHSN26100006 from the NCI and cooperative agreement 5NU58DP003875-04-00 from the CDC.; The collection of cancer incidence data used in this study was supported by the California Department of Public Health pursuant to California Health and Safety Code Section 103885; Centers for Disease Control and Prevention’s (CDC) National Program of Cancer Registries, under cooperative agreement 5NU58DP003862-04/DP003862; the NCI’s Surveillance, Epidemiology and End Results Program under contract HHSN261201000140C awarded to the Cancer Prevention Institute of California, contract HHSN261201000035C awarded to the University of Southern California (USC), and contract HHSN261201000034C awarded to the Public Health Institute.; The ideas and opinions expressed herein are those of the author(s) and endorsement by the State of California, Department of Public Health, the NCI, and the CDC or their Contractors and Subcontractors is not intended nor should be inferred.; Research reported in this publication was supported by the National Cancer Institute (NCI) of the National Institutes of Health under award number P01CA163233 to the University of Michigan.
• Keywords: Decision Making; Oncologists; Humans; Adult; Breast cancer; Comorbidity; Aged; SEER Program; Oncologist; Neoplasm Grading; Female; Neoplasm Staging; Middle Aged; Breast Neoplasms; Patients; Young Adult; Odds Ratio; Chemotherapy; Recurrence score assay
• Research Categories: Health Sciences, Oncology

Abstract

Purpose: We know little about whether it matters which oncologist a breast cancer patient sees with regard to receipt of chemotherapy. We examined oncologists’ influence on use of recurrence score (RS) testing and chemotherapy in the community. Methods: We identified 7810 women with stages 0-II breast cancer treated in 2013-15 through the SEER registries of Georgia and Los Angeles County. Surveys were sent 2 months post-surgery, (70% response rate, n = 5080). Patients identified their oncologists (n = 504) of whom 304 responded to surveys (60%). We conducted multi-level analyses on patients with ER-positive HER2-negative invasive disease (N = 2973) to examine oncologists’ influence on variation in RS testing and chemotherapy receipt, using patient and oncologist survey responses merged to SEER data. Results: Half of patients (52.8%) received RS testing and 27.7% chemotherapy. One-third (35.9%) of oncologists treated >50 new breast cancer patients annually; mean years in practice was 15.8. Oncologists explained 17% of the variation in RS testing but little of the variation in chemotherapy receipt (3%) controlling for clinical factors. Patients seeing an oncologist who was one standard deviation above the mean use of RS testing had over two-times higher odds of receiving RS (2.47, 95% CI 1.47–4.15), but a parallel estimate of the association of oncologist with the odds of receiving chemotherapy was much smaller (1.39, CI 1.03–1.88). Conclusions: Clinical algorithms have markedly reduced variation in chemotherapy use across oncologists. Oncologists’ large influence on variation in RS use suggests that they variably seek tumor profiling to inform treatment decisions.