Abstract P2-14-20: The impact of recurrence score versus sentinel lymph node biopsy on treatment decisions in early breast cancer
Authors: Fowler Rachel L , Lew Kaitlyn P , Dizon Don S , Ciambella Chelsey C , Wakeley Michelle , Taneja Charu , Wiggins Doreen L , Lopresti Mary L , Constantinou Maria , Strenger Rochelle , Wang Yihong , Fenton Mary A , Graves Theresa 
Published: March 2020

Abstract
Rationale: Choosing Wisely: In an era of genomic medicine, what role does nodal information play in decisions regarding adjuvant chemotherapy for early-stage, hormone receptor-positive breast cancer ?
Authors: Fowler RL, Lew KP, Dizon DS, Ciambella CC, Wakeley M, Taneja C, Wiggins DL, Lopresti ML, Constantinou M, Strenger R, Wang Y, Fenton MA, Graves TA.
BACKGROUND/OBJECTIVES: For women with hormone receptor-positive (HR+) breast cancer, the Recurrence Score (RS) informs prognosis and impacts treatment decisions; whether and to what degree nodal information impacts these decisions is not clear. We conducted a retrospective review of patients with newly diagnosed HR+ early stage breast cancer who underwent a sentinel lymph node biopsy (SLNB) and had the RS obtained to discriminate the impact both evaluations had on the use of adjuvant chemotherapy. We hypothesized that for these patients, the RS supersedes nodal information in determining adjuvant treatment.
METHODS: 416 patients with T1 to T2 breast cancers seen at our multidisciplinary clinic between 2013 and 2017 were identified. Data collected included demographics, node stage, RS, and adjuvant therapies. RS was stratified in to High, Intermediate, and Low Risk according to criteria used in the TAILORx trial. Continuous variables were analyzed using descriptive statistics and categorical variables were analyzed by Chi-Square or Fisher’s Exact Test. All statistics were performed using STATA 15.0.
RESULTS: For this cohort, the median age was 59 years (range 27-79). The vast majority (94%) underwent initial surgical excision or mastectomy with SLNB. Of these, 338 patients (81%) had node-negative disease. Of the remaining, 37 patients (8.9%) had micro-metastasis to a single node, 39 (9.3%) had N1a disease, including one patient with 3 positive lymph nodes. RS risk was characterized as high, intermediate, and low in 12, 65, and 23%, respectively. On multivariate analysis, only age at diagnosis (p&lt;0.05) and RS (p&lt;0.0005) were significantly associated with the use of adjuvant chemotherapy; nodal status was not significant (p&gt;0.05).
CONCLUSIONS: For women with early-stage, clinically node-negative, HR+ breast cancer, the RS and age of the patient was associated with the administration of adjuvant chemotherapy. Although these data are limited to recommendations surrounding adjuvant chemotherapy and not decisions surrounding adjuvant radiation therapy, these data support the Choosing Wisely™ campaign against routine use of SLNB in low-risk patients.
Citation Format: Rachel L Fowler, Kaitlyn P Lew, Don S Dizon, Chelsey C Ciambella, Michelle Wakeley, Charu Taneja, Doreen L Wiggins, Mary L Lopresti, Maria Constantinou, Rochelle Strenger, Yihong Wang, Mary A Fenton, Theresa Graves. The impact of recurrence score versus sentinel lymph node biopsy on treatment decisions in early breast cancer [abstract]. In: Proceedings of the 2019 San Antonio Breast Cancer Symposium; 2019 Dec 10-14; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2020;80(4 Suppl):Abstract nr P2-14-20.