Abstract:Objecitve To investigate the expression of ferritin light chain (FTL) in non-small cell lung cancer (NSCLC) tissues and its relationship with clinicopathological characteristics and prognosis of NSCLC patients. Methods By immunohistochemistry (IHC) method, the expression level of FTL in NSCLC and para-cancerous tissues was detected, and its relationship with the clinicopathological characteristics of NSCLC patients was analyzed.The correlation between FTL expression level and prognosis of NSCLC was analyzed by Kaplan Meier plotter online database. Results The expression level of FTL in cancer tissues was significantly higher than that in adjacent tissues (χ²=16.859，P<0.01).There was no significant correlation between the expression level of FTL in cancer tissues and the clinicopathological characteristics of NSCLC patients(P>0.05).Survival analysis of Kaplan-Meier Plotter online database showed that high expression of FTL was correlated with poor overall survival (OS) of NSCLC patients [P=0.000 8，HR=1.27 (1.10-1.45)]，but not with progression-free survival time (PFS).In patients with lung adenocarcinoma，FTL expression was statistically correlated with OS[P=0.000 0, HR=2.20(1.69-2.86)] and PFS [P=0.000 5, HR=1.74(1.27-2.40)], and the higher the expression, the worse the survival.However, the expression of FTL was not associated with OS and PFS in patients with lung squamous-cell carcinoma.As the censored value for OS, the expression of FTL was only related to the prognosis of patients with clinical stage Ⅰ and Ⅱ[(P=0.000 0, HR=2.12 (1.56-2.87); P=0.000 0, HR=2.22 (1.49-3.32)].As the cutoff value for PFS, FTL was only related to the prognosis of patients with stage Ⅰ[P=0.0154, HR=1.74(1.11-2.74)]. Conclusion High expression of FTL is not associated with clinicopathological features but associated with poor prognosis in NSCLC patients.FTL can be used to evaluate the prognosis of NSCLC patients.