Abstract 84P
Background
Recent studies suggest immune infiltrates in primary tumors and metastases can serve as independent prognostic biomarkers and predict efficacy of platinum-based anticancer drugs in patients with non-small cell lung cancer patients (NSCLC).The study of subsets of (TILs) is crucial, as they exhibit distinct physiological and pathological implications within the tumour microenvironment.
Methods
From January 2016 to December 2018, we conducted a prospective study on 50 chemotherapy naive patients with advanced stage NSCLC. CD3, CD4, CD8 and FOXP3 lymphocytes were detected in paraffin embedded tumor tissues by stained slides (H&E). We studied the average density of TILs subgroups using the median values as cut-off, which was categorized on whether they above or below the median value. All patients received gemcitabine and platinum agents. Assessment of (TILs), correlation with overall response rate (ORR), TTP and OS were done. Tumor response was assessed by RECIST v1.1.
Results
A significant association was seen between the density of CD4 and CD8 (TILs) and the clinical benefit response to chemotherapy, with (p- 0.048 and 0.034, respectively) but no correlation with FOXP3 and CD3. Low FOXP3 levels resulted in longer OS and TTP in patients (p = 0.016 and p = 0.006 respectively) while decreased FOXP3/CD4 ratio was associated with prolonged OS and TTP (P-0.026 and 0.016 respectively). In multivariate analysis, a statistically significant link was found between FOXP3 level and the presence of a lung nodule. This showed a high hazard ratio (HR) for OS (p-0.001 and 0.036, respectively) and a higher risk of progression for FOXP3 level. Moreover, there is a correlation between performance status and TTP.
Conclusions
Platinum treatments predict prognosis and treatment response by assessing high CD8, low FOXP3/CD4 ratio, and FOXP3 TIL infiltration in tumor environments. Understanding micro-environmental immune milieu significance is crucial for prognosis and treatment response.
Legal entity responsible for the study
M. Eissa.
Funding
Has not received any funding.
Disclosure
All authors have declared no conflicts of interest.