Abstract 3713
Background
Decision making on adjuvant systemic therapy in women with primary node-negative, HR+ breast cancer and intermediate risk scores on a molecular tumor profile has often been difficult, and may be based also on additional clinical factors such as age, tumor size and grade. In mid-2018 new level 1 evidence on the lack of additional benefit with chemo-hormonal therapy versus hormonal therapy for most of these patients emerged. We sought to determine if systemic adjuvant therapy choices have changed in a large community practice of over 200 medical oncologists in the U.S. using in-house tumor testing with the Prosigna PAM 50 assay. There is robust clinical evidence on recurrence risk estimation with PAM 50. Data from the ABCSG-8 estimates distant RFS of 91.3% at ten years in the intermediate risk group treated with hormonal therapy alone. Decreased chemo use would lead to decreased therapy-related toxicity and probable healthcare cost savings.
Methods
We compared Prosigna ROR results in individual postmenopausal women with HR+, node- primary breast cancers from the period 9/17 through 6/18, with the period 6/18 through 3/19. Approximately 800 total tests were run from one large practice in the U.S. About 20% fell into the intermediate score range We compared the number of patients receiving adjuvant chemohormonal therapy versus hormonal therapy alone or no systemic therapy. Physicians were polled as to whether their decisions were influenced by the ROR score, clinical factors, or both.
Results
During the period studied, the percentage of patients with intermediate ROR scores receiving adjuvant therapy declined. Physicians based their decisions on the scores primarily, along with other clinical factors. The percentages of physicians influenced by each factor and the totals for each category of treatment will be presented in the final poster.
Conclusions
Oncologists in a large practice are influenced in making breast cancer adjuvant therapy decisons by recent trial data, as well as clinical factors, and may extrapolate from one molecular profile to another. Adjuvant chemo use in HR+ node- patients is likely to remained confined to patients with a high-risk profile, regardless of the assay used.
Clinical trial identification
Editorial acknowledgement
Legal entity responsible for the study
Florida Cancer Specialists.
Funding
Has not received any funding.
Disclosure
L.L. Hart: Advisory / Consultancy, Travel / Accommodation / Expenses: Self. All other authors have declared no conflicts of interest.
Resources from the same session
5812 - Correlation between the density of tumor-infiltrating lymphocytes, immune cell subsets in tumor stroma and response to systemic therapy in breast cancer
Presenter: Cvetka Grasic Kuhar
Session: Poster Display session 2
Resources:
Abstract
4734 - BRCA1/2 Testing in HER2- Advanced Breast Cancer (ABC): Results from the European Component of a Multi-Country Real World Study
Presenter: Michael Patrick Lux
Session: Poster Display session 2
Resources:
Abstract
1686 - In vitro and in vivo rescue of resistance to BET inhibitors by targeting PLK1 in triple negative breast cancer.
Presenter: Cristina Nieto-jiménez
Session: Poster Display session 2
Resources:
Abstract
5020 - Neoadjuvant endocrine therapy in combination with melatonin and metformin in locally advanced breast cancer
Presenter: Tatiana Semiglazova
Session: Poster Display session 2
Resources:
Abstract
5082 - Melatonin and metformin in neoadjuvant chemotherapy in locally advanced breast cancer
Presenter: Tatiana Semiglazova
Session: Poster Display session 2
Resources:
Abstract
2642 - Patient-tailored tamoxifen dosing based on an increased quantitative understanding of its complex pharmacokinetics: A novel integrative modelling approach
Presenter: Anna Mueller-Schoell
Session: Poster Display session 2
Resources:
Abstract
2461 - Lack of benefit of neoadjuvant pertuzumab in high risk HER2 positive breast cancer. A retrospective case-control study of 355 cases with biomarker analysis.
Presenter: Manuela Tiako Meyo
Session: Poster Display session 2
Resources:
Abstract
4776 - Targeting CDCA3 to improve chemotherapy response in triple-negative breast cancer patients
Presenter: Kenneth O'Byrne
Session: Poster Display session 2
Resources:
Abstract
1674 - Activity of BET-proteolysis targeting chimeric (PROTAC) compounds in triple negative breast cancer
Presenter: María Del Mar Noblejas López
Session: Poster Display session 2
Resources:
Abstract
5629 - Outcome of triple negative inflammatory breast cancers (TNIBC) treated with dose dense neoadjuvant epirubicin cyclophosphmide, prognostic impact of pre and post neoadjuvant chemotherapy (NAC) tumor infiltrating lymphocytes (TIL) and post NAC lymphovascular invasion
Presenter: Luca Campedel
Session: Poster Display session 2
Resources:
Abstract