npj Breast Cancer (Jun 2023)

Clinical outcomes in estrogen receptor-positive early-stage breast cancer patients with Recurrence Score 26-30: observational real-world cohort study

  • Ofer Rotem,
  • Idit Peretz,
  • Michelle Leviov,
  • Iryna Kuchuk,
  • Amit Itay,
  • Margarita Tokar,
  • Shani Paluch-Shimon,
  • Ofra Maimon,
  • Rinat Yerushalmi,
  • Karen Drumea,
  • Ella Evron,
  • Amir Sonnenblick,
  • Einav Gal-Yam,
  • Hadar Goldvaser,
  • Yosef Samih,
  • Rotem Merose,
  • Avital Bareket-Samish,
  • Lior Soussan-Gutman,
  • Salomon M. Stemmer

DOI
https://doi.org/10.1038/s41523-023-00549-8
Journal volume & issue
Vol. 9, no. 1
pp. 1 – 8

Abstract

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Abstract Data on adjuvant chemotherapy (CT) benefit in ER + HER2‒ early-stage breast cancer (EBC) patients with Recurrence Score (RS) 26-30 are limited. This real-world study evaluated the relationships between the RS, adjuvant treatments, and outcomes in 534 RS 26-30 patients tested through Clalit Health Services (N0: n = 394, 49% CT-treated; N1mi/N1: n = 140, 62% CT-treated). The CT-treated and untreated groups were imbalanced (more high-risk clinicopathologic characteristics in CT-treated patients). With median follow-up of 8 years, Kaplan–Meier estimates for overall survival (OS), distant recurrence-free survival (DRFS), and BC-specific mortality (BCSM) were not significantly different between CT-treated and untreated N0 patients. Seven-year rates (95% CI) in CT-treated vs untreated: OS, 97.9% (94.4–99.2%) vs 97.9% (94.6–99.2%); DRFS, 91.5% (86.6–94.7%) vs 91.2% (86.0–94.6%); BCSM, 0.5% (0.1–3.7%) vs 1.6% (0.5–4.7%). For N1mi/N1 patients, OS/DRFS did not differ significantly between treatment groups; whereas BCSM did (1.3% [0.2–8.6%] vs 6.2% [2.0–17.7%] for CT-treated and untreated patients, respectively, p = 0.024).