Prognostic value of tumor-infiltrating lymphocytes (TILS) and their association with clinicopathological features in breast cancer: A retrospective study involving 53 cases

Abstract

ObjectiveQuantitative analysis of tumor-infiltrating lymphocytes (TILs) is currently considered as a prognostic factor in several malignant tumors. The aim of our study was to assess the prognostic value of TILs in breast cancers and its association with other clinicopathological prognostic factors in non-specific type (NST) breast carcinoma in Tunisian population. MethodsRetrospective study included 53 women with NST breast carcinoma. The data were collected over a period of 13 months with a follow-up of 40 months for all the patients. The TILs were evaluated according to the 2014 recommendations of the international working group on TILs. ResultsTILs level was between 3% and 60% with mean of 21%. Ten patients had lymphocyte predominant breast cancer (LPBC). Statistical analysis had shown that the TILs level ≤50% was associated with the presence of vascular emboli and the absence of HER2 amplification. Inflammatory-type carcinoma and HER2 amplification significantly worsened OS. Presence of vascular emboli, lymph node metastases, inflammatory type of carcinoma, TILs ≤50%, and absence of estrogen receptors (ER) were associated with reduced RFS. In multivariate analysis, the presence of vascular emboli was an independent factor for OS. TILs ≤50%, inflammatory type of carcinoma and presence of vascular emboli were independent risk factors for RFS. ConclusionThis Tunisian pilot study showed higher level of TILs in NST breast carcinomas is associated with improved RFS. The therapeutic implications will benefit from multiple research studies including ours on the predictive value of TILs for neoadjuvant or adjuvant treatment.