Impact of the lymphovascular invasion on the prognosis in pT1-2N0 early breast cancer.

Abstract

e12517 Background: Lymphovascular invasion (LVI) has historically been considered a poor prognostic factor in breast cancer. However, the clinical impact of LVI on breast cancer prognosis has not been fully investigated in the recent era, when the concept of tumor subtypes and the application of multigene assays in determining adjuvant therapy are well established. Methods: A total of 1340 patients with pT1-2N0M0 (pStage I-IIA) breast cancer were included, who underwent surgery without neoadjuvant systemic therapy between 2010 and 2020. The relationships between Ly and clinicopathological factors and prognosis (relapse-free survival; RFS, distant metastasis-free survival; DMFS) were analyzed. Results: Among 1340 patients, LVI was positive in 100 (7.5%) patients (Ly1) and in other 1240 (92.5%) patients, LVI was negative (Ly0). LVI was significantly associated with premenopausal women, large tumor size, higher histological grade (HG), higher Ki67 and higher rate of postoperative adjuvant chemotherapy. There were no associations between LVI and estrogen receptor (ER), hormone receptor (HR), HER2 and tumor subtypes. Among these cases, data of Oncotype Dx were available in 41 cases (Ly0 34 cases, Ly1 7cases). There was no relationship between LVI and recurrence score (RS) (Ly1; RS 15.1±2.9, Ly0; RS 18.3±1.3, p=0.3295). The prognosis of the patients with Ly1 was significantly poorer in terms of RFS and DMFS compared with that of those with Ly0. These relationships were evident in premenopausal women, tumor size of pT1c, HG II, and HR+/HER2- subtype. Adjuvant chemotherapy did not improve the prognosis of patients with LVI. Ly1 was a poor prognostic factor in univariate and multivariate analyses in terms of both RFS and DMFS. Conclusions: LVI was shown to be a poor prognostic factor for pT1-2N0 early breast cancer even in recent years. Benefits of adjuvant chemotherapy for improving prognosis not clear, however, LVI should be considered as an important factor in determining adjuvant systemic therapy, especially in premenopausal women, pT1c, HG II, HR+/HER2- cases.