Background: Lymphovascular invasion (LVI) is known to be associated with a poor outcome in breast cancer patients. It indicates a highly proliferative cancer. Few studies examined the value of LVI as a predictor for outcome after neoadjuvant chemotherapy (NAC). The aim of this study to look for an association between survival outcomes and clinicopathological features in locally advanced breast cancer patients treated with NAC and to identify the predictors of nodal pathologic complete response (PCR). Methods:This study is a retrospective analysis of 224 women with locally advanced breast cancer who underwent NAC between 2011-2020. Kaplan-Meier analyses were used to assess the associations between disease-free survival (DFS) and overall survival (OS) and all clinicopathological variables including LVI in breast surgical specimens following NAC. Associations between nodal PCR and all clinicopathologic variables were assessed Results:Median follow-up was 29.9 months. Absence of nodal PCR (p.000), positive family history (p .027), clinical T4 (p.049), pathological TNM staging (p.016), high tumor grade (p .020),triple negative disease(p .016) and absence of tumor PCR (p.001) were associated with worse disease free survival. Absence of nodal PCR (p.002), high BMI (p.039), multicentric disease (p.026), high tumor grade, triple negative disease (p.018), and absence of tumor PCR (p.005) were associated with worse overall survival. LVI was found in 53 of surgical specimens (23.7%). It was associated with worse DFS (HR) (2.967) 95% CI (1.7-4.9), p.000 and overall survival (HR) (3.05) 95% CI (1.525-6.09), p.002). Nodal PCR significantly correlated with T stage (p .013), LVI (p.000), ER status (p.004), PR status (p.003), Her2neu status and IHC score (p.000), tumor subtype (p.000), tumor PCR (p.000), DFS (p.000), and OS (p.000). Conclusion:LVI is significantly associated with worse DFS and OS in locally advanced breast cancer patients treated with NAC. This data confirmed the previously published recommendation to add LVI to the pathological staging system. LVI may be further explored as a guide for adjuvant treatment options in clinical trials. Nodal PCR is another significant predictor of outcome and is associated significantly with tumor PCR and LVI. Both tumor PCR and LVI can be used as criteria for axillary surgery omission in future trials.
Citation Format: Omima Elemam, Khaled Elnaghi, Ziad Emarah, Hossam Alghanami, Seham Abdelkhalek. Residual lymphovascular invasion: Predicts the outcome of neoadjuvant chemotherapy in locally advanced breast cancer [abstract]. In: Proceedings of the 2021 San Antonio Breast Cancer Symposium; 2021 Dec 7-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2022;82(4 Suppl):Abstract nr P4-07-30.