A28 - TILs evaluation in early stages of NSCLC

Abstract

Background: There is an increasing evidence supporting tumor-infiltrating lymphocytes (TILs) as a prognostic and predictive factors in different human neoplasm (melanoma, colon rectal, triple negative breast cancer), actually a positive correlation was found between total TILs levels and better outcomes independently from the TNM classification. Material (patients) and methods: We retrospectively evaluated the correlation between TILS and prognosis in early stage of NSCLC operated at our Hospital from 2012 to 2013 and we made a comparison with classic clinical-pathological features (stage, T, N, histological type, adjuvant treatment, chronic corticosteroid treatment and smoking habits) by performing univariate analysis of survival. Determination of TILs has been performed on FFPE tissue samples and characterized with pathologic examinations of H&E-stained sections. Tumor-infiltrating lymphocytes (TILs) are usually measured using subjective methods. In the absence of a standardized methodology for evaluating TILs in NSCLC, we took as a reference the recommendations by International TILs Working Group 2014 for breast cancer (Salgado et Al.) Results: We collected data from 58 pts, median age 71 (range 42-85), 49 pts with stage I e 9 pts stage II, 58% pts with adenocarcinoma, 32,7% squamocellular carcinoma and 8% with neuroendocrine/large cell carcinoma. The OS and DFS at 48 months of follow up was respectively 77,6% and 74,1 %. The presence of low level of TILs (< 10%) was found in 57% pts and middle-high (>10%) in 43% of them. The increased level of TILs was significantly correlated with OS (p 0,044) but not with PFS (0,391) in our analysis. The totality of patient with squamocellular histological subtype and middle-high level of TILs was alive at 48 months, although p value wasn't statistically significant. No other significant correlations has been found with the other clinical-pathological features. Conclusions: In our population the quantitative measurement of TILs have been shown to provide a prognostic significance, although their inclusion in the diagnostic practice necessitates a wide recognized method together with the characterization of the lymphocytes subtypes that seems to have different predictive value.