Publication-only abstracts (abstract number preceded by an "e"), published in conjunction with the 2018 ASCO Annual Meeting but not presented at the Meeting, can be found online only.
Using the National Cancer Data Base (NCDB) and Oncotype DX data to predict adjuvant therapy effect on overall survival (OS) of N0 & N1 breast cancer patients.
2018 ASCO Annual Meeting
J Clin Oncol 36, 2018 (suppl; abstr e12529)
Author(s): Amila Orucevic, Heidel Robert, John Lawrence Bell; University of Tennessee Medical Center, Knoxville, TN
Background: The newest 4.2017 version of the NCCN guidelines incorporates the Oncotype DX (ODX) breast cancer (BC) assay into the algorithm for utilization of systemic adjuvant therapy (tx) for hormone receptor positive, HER2 negative, pT1-pT3, N0/N1mi BC patients (pts). Endocrine therapy (ET) alone is recommended for ODX low recurrence score (RS 0-17); chemotherapy (CTx) followed by ET for high RS (31-100), and either for intermediate RS (18-30) or when no assay is performed. Recommendations are category 1 evidence based on published 5-year results from the TAILORx trial that used ODX scores to guide tx, although with different RS cutoff points. The ongoing RxPONDER trial examines the same algorithms in pts with 1-3 + lymph nodes. Methods: We analyzed the impact of ODX utilization on 5-year (yr) OS of invasive BC pts in a retrospective observational study of the NCDB following TAILORx & RxPONDER pts’ inclusion criteria: 6-50 mm tumors, N0/N1, M0, ER+/HER2-, ±postsurgical adjuvant systemic tx, no comorbidities and pts' age from 18-75. Demographic and clinical variables of pts with and without ODX results collected in 2010 were compared (ODX vs No ODX; last follow-up day 12/2015). Frequencies, chi-square, Kaplan-Meier, Cox and logistic regression analyses were used. Results: There were 27,697 T1-T2, N0 pts: 9,607 ODX & 18,090 No ODX; 8,006 T1-T2, N1 pts: 1,537 ODX & 6,469 No ODX. When compared to No ODX, ODX pts were: younger, had larger, higher grade tumors, lower number of positive lymph nodes (ODX N1), ODX N0 received more CTx and more ET, but less CTx when ODX N1 (p< 0.05). Significant predictors of mortality were: no ODX testing, older age, black race, larger tumors, higher grade, N1 status (p< 0.05). Five yr OS of ODX pts was better than No ODX (97.3% vs 96.2% for N0; 95.9 vs 93.5% for N1, p< 0.05); however, the duration of this advantage although significant was short (0.8 months). ODX linear RS result was predictive of CTx benefit for OS in N0 pts, but not for N1 pts. Conclusions: Our results showed that ODX linear RS result was predictive of CTx benefit for OS in N0 pts, but not N1 pts. The predictive value of ODX testing for OS in N1 pts will likely be clarified in the RxPONDER trial.
1. TAILORx: Phase III trial of chemoendocrine therapy versus endocrine therapy alone in hormone receptor-positive, HER2-negative, node-negative breast cancer and an intermediate prognosis 21-gene recurrence score.