Why use the Oncotype DX Breast Recurrence Score® test in the neoadjuvant setting?
Neoadjuvant therapy administered before surgery may:
- Improve the likelihood of successful breast-conserving surgery through tumor shrinkage1
- Downstage the nodal status in the axilla1
- Help assess primary tumor response to systemic therapy1
To help patients reach these outcomes, the Breast Recurrence Score® test is a proven predictor of response to neoadjuvant treatment among postmenopausal women with node-negative breast cancer and provides useful information to help guide systemic treatment decisions2-6:
TransNEOS study: neoadjuvant endocrine therapy and Oncotype DX® test6
Patients in the TransNEOS study (a translational study of New Primary Endocrine-therapy Origination Study [NEOS]) had tumors ≥2 cm and archived core-biopsy samples taken before neoadjuvant letrozole and subsequently were sent for Breast Recurrence Score testing. A total of 295 patients were included in TransNEOS.
Primary: Evaluate clinical (complete or partial) response to neoadjuvant letrozole for Recurrence Score results <18 vs Recurrence Score results ≥31
Secondary: Evaluate clinical response and rate of breast-conserving surgery by continuous Recurrence Score test result
The Recurrence Score result group, which compared patients with Recurrence Score results 0-17 to patients with Recurrence Score results 31-100, was significantly associated with the rate of clinical response (χ2 test, P<0.001).
Even when including patients with Recurrence Score results of 18-30, the Recurrence Score result group remained significantly associated with the rate of clinical response (Cochran–Armitage trend test, P<0.001).
The Recurrence Score result group was not associated with breast-conserving surgery candidacy before neoadjuvant letrozole but was significantly associated with breast-conserving surgery received after treatment (table to the right).
Among patients with Recurrence Score results 0-17, pretreatment surgery recommendation significantly differed from posttreatment surgery received (McNemar’s test, P<0.001), whereas there was no significant change among patients with Recurrence Score results 31-100 (P=0.075).
The authors concluded that the TransNEOS study validates the Recurrence Score result as a significant predictor of clinical response to neoadjuvant letrozole in postmenopausal women with estrogen receptor-positive (ER+), human epidermal growth factor receptor 2-negative (HER2-), clinically node-negative breast cancer.
WSG ADAPT trial: neoadjuvant chemotherapy studies with the Oncotype DX test7
A predictor of response to neoadjuvant chemotherapy
The National Cancer Database was used to identify all patients with T1-T3, ER+, HER2- primary breast cancer from 2010 to 2015 who had the Breast Recurrence Score test performed and received neoadjuvant chemotherapy (N=989). Recurrence Score results were strongly associated with the likelihood of pathologic complete response.8
Distribution by RS Group:
- RS 0-17: 23.0%
- RS 18-30: 45.5%
- RS 31-100: 31.5%
RS=Recurrence Score result.