Association of 21-gene recurrence score and locoregional recurrence in early breast cancer patients

Article type: Research Article

Authors: Zeng, Yufei¹ | Gao, Weiqi¹ | Chen, Xiaosong^* | Shen, Kunwei^*

Affiliations: Department of General Surgery, Comprehensive Breast Health Center, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China

Correspondence: [*] Corresponding authors: Xiaosong Chen, 197 Ruijin Second Road, Shanghai, China. Tel.: +86 21 64370045 602102; Fax: +86 21 64156886; E-mail: [email protected]. Kunwei Shen, 197 Ruijin Second Road, Shanghai, China. Tel.: +86 21 64370045 602208; Fax: +86 21 64156886; %****␣cbm-35-cbm210274_temp.tex␣Line␣125␣**** E-mail: [email protected].

Note: [1] These authors have contributed equally to this work.

Abstract: BACKGROUND: The 21-gene recurrence score (RS) assay has been validated to predict the risk of disease-free survival in estrogen receptor (ER)-positive, human epidermal growth factor receptor 2 (HER2)-negative early breast cancer patients. However, its relation with locoregional recurrence (LRR) risk is unclear. OBJECTIVE: This study aimed to explore the ability of RS to predict LRR risk. METHODS: Consecutive ER-positive, HER2-negative, pT1, pN0-1, and M0 early breast cancer patients were analyzed retrospectively. According to RS, patients were divided into low- (RS < 18), intermediate- (RS 18–30), and high-risk (RS ⩾ 31) groups. The primary endpoint was LRR. Subgroup analysis was conducted according to different nodal statuses and surgery types. RESULTS: A total of 1558 patients were enrolled: 354 (22.7%), 788 (50.6%), and 416 (26.7%) patients in the low-, intermediate-, and high-risk groups, respectively. The median follow-up time was 53 months, and 2, 8, and 14 LRR events were observed in the low-, intermediate-, and high-risk groups, respectively (P= 0.004). Both univariate (P= 0.009) and multivariate (P= 0.010) analyses demonstrated that 21-gene RS was correlated with LRR. Compared to low-risk patients, high-risk patients were at greater risk of LRR (HR 5.75, 95% CI 1.30–25.31, P= 0.021). Among pN0 (P= 0.033), pN1 (P= 0.049) and postmastectomy patients (P= 0.012), 21-gene RS remained predictive of the risk of LRR. CONCLUSION: The 21-gene RS assay was significantly associated with the risk of LRR in ER-positive, HER2-negative early breast cancer patients. Among patients with different nodal statuses and patients receiving mastectomy, RS remained predictive of the risk of LRR.

Keywords: 21-gene RS assay, breast cancer, locoregional recurrence, mastectomy, breast-conserving surgery

DOI: 10.3233/CBM-210274

Journal: Cancer Biomarkers, vol. 35, no. 1, pp. 111-118, 2022