The 21-gene Recurrence Score® (RS) assay is a validated prognostic/predictive tool in ER + early-stage breast cancer. However, clinical outcome data from prospective studies in RS ≥ 11 patients are lacking, as are relevant real-life clinical practice data. In this retrospective analysis of a prospectively designed registry, we evaluated treatments/clinical outcomes in patients undergoing RStesting through Clalit Health Services. The analysis included N0 ER + HER2-negative breast cancer patients who were RS-tested from 1/2006 through 12/2010. Medical records were reviewed to verify treatments/recurrences/survival. The cohort included 1801 patients (median follow-up, 6.2 years). Median age was 60 years, 50.4% were grade 2 and 81.1% had invasive ductal carcinoma; 48.9% had RS < 18, 40.7% RS 18–30, and 10.4% RS ≥ 31, with chemotherapy use of 1.4, 23.7, and 87.2%, respectively. The 5-year Kaplan–Meier estimates for distant recurrence were 0.8, 3.0, and 8.6%, for patients with RS < 18, RS 18–30 and RS ≥ 31, respectively; the corresponding 5-year Kaplan–Meier estimates for breast cancer death were 0.0, 0.9, and 6.2%. Chemotherapy-untreated patients with RS < 11 (n = 304) and 11–25 (n = 1037) (TAILORx categorization) had 5-year Kaplan–Meier estimates for distant recurrence risk/breast cancer death of 1.0%/0.0% and 1.3%/0.4%, respectively. Our results extend those of the prospective TAILORx trial: the 5-year Kaplan–Meier estimates for distant recurrence and breast cancer death rate for the RS < 18 patients were very low supporting the use of endocrine therapy alone. Furthermore, in chemotherapy-untreated patients with RS 11–25 (where TAILORx patients were randomized to chemoendocrine or endocrine therapy alone), 5-year distant recurrence rates were also very low, suggesting that chemotherapy would not have conferred clinically meaningful benefit.
Bibliographical noteFunding Information:
This work was supported by grant 1132 from Teva Pharmaceuticals Ltd that was awarded to Dr. Stemmer via Mor Research Applications Ltd (a company that manages research grants secured by Clalit Health Services doctors/researchers) for the purpose of this work.
Competing Interests: Dr. Stemmer reports receiving grant funding from Teva and travel expenses (flights, accommodation) from Genomic Health, Inc. Dr. Soussan-Gutman reports being employed by and holding stock options in Teva Pharmaceutical Industries Ltd. Dr. Bareket-Samish reports being a consultant for Teva Pharmaceutical Industries Ltd. and Genomic Health Inc. Dr. Ben Baruch reports receiving personal fees from Genomic Health Inc (for participating in the Speaker’s Bureau program). Dr. Rosengarten reports receiving payments for lectures and grants for traveling to conferences from Teva Pharmaceutical Industries Ltd. Dr. Svedman, Ms. McCullough, Dr. Maddala, and Dr. Shak report being employed by and stock ownership in Genomic Health, Inc. Dr. Shak also reports having multiple patents for the Oncotype DX assay (for which all rights were assigned to Genomic Health, Inc.). Drs. Steiner, Rizel, Geffen, Nisenbaum, Isaacs, Fried, Uziely, Klang, Zidan, Ryvo, Kaufman, Evron, Karminsky, Goldberg, and Liebermann report no conflict of interest.
© The Author(s) 2017.
ASJC Scopus subject areas
- Radiology Nuclear Medicine and imaging
- Pharmacology (medical)