Influência dos linfócitos tumorais infiltrantes no prognóstico e na sobrevida de pacientes com câncer de mama submetidas a quimioterapia neoadjuvante

Abstract

Introduction: This study provides a comprehensive overview of breast cancer, highlighting its heterogeneous aspects and challenges in treatment, with a focus on assessing the prognosis of high-risk patients. Neoadjuvant chemotherapy (NAC) provides an in vivo validation model capable of testing the efficiency of drugs through the pathological response of the tumor, observed during surgery. Identifying tumor factors associated with this response, and better clinical outcomes has been a challenge. Consequently, the assessment of tumor-infiltrating lymphocytes (TILs) as markers of response to neoadjuvant chemotherapy in breast cancer has gained prominence in recent years. This study aims to evaluate the predictive and prognostic effects of TILs, based on their quantification in biopsy samples from patients undergoing neoadjuvant chemotherapy, contributing to more individualized therapeutic approaches in clinical mastology practice. Objectives: Evaluate if there is influence of TILs on the overall survival and 5-year survival of breast cancer patients undergoing NAC, as well as their relationship with pathological tumor response to treatment, stratifying among various molecular subtypes. Patients and Methods: This is a survival study with uni-and multivariate analyses, using a retrospective cohort of cases treated between 2011 and 2017 at the University Hospital of Sergipe. Biopsy slides were reanalyzed for TILs quantity. Cox proportional hazards models were used for independent analysis of each clinical and pathological variable with survival, and for survival analysis, the Kaplan-Meier method was employed, relating the quantity of TILs in the initial tumor to complete pathological response and 5-year survival. Results: There were differences in pathological parameters between patients who were alive and those who deceased. No significant difference was observed in TILs expression among molecular subtypes. The calculated median was 5, and over half (63%) of the population had TILs < 5%. No relationship between TILs and overall survival (OS) was demonstrated. However, in the 5-year survival analysis (5YS), patients with TILs below 5% showed better outcomes in all molecular subtypes (p<0,05). Conclusion: Patients with TILs < 5% in biopsy samples exhibited improved 5-year survival.