Oncotype DX Breast Recurrence Score Distribution and Chemotherapy Benefit Among Women of Different Age Groups With HR-Positive, HER2-Negative, Node-Negative Breast Cancer in the SEER Database.

Ran Cheng,Xiangyi Kong,Xiangyu Wang,Yi Fang,Jing Wang

doi:10.3389/fonc.2020.01583

Abstract

Objective: To explore the distribution of Oncotype DX Breast Recurrence Score (RS), the proportion of receiving chemotherapy, and the relationship between RS and chemotherapy benefit according to detailed age groups in women with hormone receptor-positive, human epidermal growth factor receptor 2-negative, node-negative (HR+/HER2−/N0) breast cancer.Methods: This was an extensive, comprehensive, population-based retrospective study. Data on individuals with breast cancer were obtained from the Surveillance, Epidemiology, and End Results (SEER) Program. The cohort was divided into five groups by age (≤ 35, 36–50, 51–65, 66–80, >80 years). RS distribution and chemotherapy proportion among different age groups were analyzed, and the overall survivals between patients receiving chemotherapy and those not/unknown were compared in each age group.Results: The study cohort comprised 49,539 patients and the largest age group was 51–65 years. The percentage of patients with low-risk RS (0–10) increased with age, whereas those with intermediate-risk RS (11–25) decreased with age (except for the group of 36–50 years, which had the highest rate of intermediate-risk RS). The age group ≤35 years has the greatest rate of high-risk RS (26–100). The proportion of receiving chemotherapy decreased with age in all RS risk categories. Overall survival was benefited by chemotherapy only in the age group of 66–80 years with intermediate- and high-risk RS, and chemotherapy seemed to do more harm than good for patients older than 80 years.Conclusions: In the present study, we identified the distribution of RS, the proportion of receiving chemotherapy, and the relationship between RS and chemotherapy benefit according to a detailed age grouping for women with HR+/HER2−/N0 breast cancer, which may help in making individualized clinical decisions.

Highlights

Breast cancer is the most common malignant tumor in women worldwide [1, 2]
The proportion of receiving chemotherapy decreases with age in all RS risk categories Age ≤ 35 with RS of 26–100 had the highest chemotherapy receipt rate, while age > 80 with RS of 0–10 had the lowest chemotherapy receipt rate Overall survival was benefited by chemotherapy only in the age group of 66–80 years of age with intermediate- and high-risk RS
Prospective trial 9,719 eligible patients with follow–up information HR+/ HER2–/ N0 April 2006 – October 2010 0–10 17% (1619/9719) 11–25 69% (6711/9719) 26–100 14% (1389/9719) A low proportion of distant recurrence at 9 years with endocrine therapy alone if the RS was 0–15, irrespective of age Age > 50 with a RS of 0–25, and ≤ 50 with a RS of 0–15, endocrine therapy was non-inferior to chemoendocrine therapy Age ≤ 50, chemotherapy was associated with some benefit for women who had a RS of 16–25 Age ≤ 50 with high clinical risk and RS [11,12,13,14,15,16,17,18,19,20,21,22,23,24,25] who received endocrine therapy alone, and those RS [26–100] who received chemoendocrine therapy, the distant recurrence rate at 9 years exceeded 10% Age ≤ 50 and RS [11,12,13,14,15,16,17,18,19,20,21,22,23,24,25], endocrine therapy was noninferior to chemoendocrine therapy at 9 years if clinical risk was low; while chemotherapy was associated with benefit if clinical risk was high Age > 50, endocrine therapy was noninferior to chemoendocrine therapy in the cohort with a RS of 11–25, regardless of clinical risk category Age ≤ 50, distant recurrence rate at 9 years were very low among women with a RS of 0–10, irrespective of clinical–risk category The chemotherapy benefit was most evident at 45 years of age in premenopausal women and waned at younger and older ages and with menopause There were significant interactions between chemotherapy treatment and age (≤50 vs. 51 to 65 vs. >65 years) for invasive disease–free survival (P = 0.03) and for freedom from recurrence of breast cancer at a distant or local–regional site (P = 0.02) but not at a distant site (P = 0.12)

Summary

Introduction

Breast cancer is the most common malignant tumor in women worldwide [1, 2]. Implementation of early screening and self-examination has resulted in increasing numbers of breast cancer patients being diagnosed at an early stage [3]. The optimal treatment of early-stage hormone receptor-positive (HR+), human epidermal growth factor receptor 2-negative (HER2–) and lymph node-negative (N0) breast cancer is currently controversial [4, 5]. Some patients achieve a higher survival rate with endocrine therapy alone, whereas others require chemotherapy to reduce the recurrence rate and mortality [6]. Because breast cancer is heterogeneous, not all patients benefit from chemotherapy [7]. The economic burden and adverse reactions caused by chemotherapy increase the patients’ economic and psychological pressure and reduce their life quality and compliance [8]

Methods

Results

Conclusion