Purpose: To investigate the association between level of serum ferritin (SF) and epidermal growth factor receptor (EGFR) mutations and to analyse the impact of SF level on survival times in advanced non-small-cell lung cancer (NSCLC) patients taking EGFR tyrosine kinase inhibitors (EGFR-TKIs).
Methods: A total of 301 patients who were admitted to the Chinese PLA general hospital from August 2015 to August 2017 were enrolled. The association between tumour markers, including SF, CEA, and EGFR mutation, and their impact on the prognosis of patients taking EGFR-TKIs was investigated.
Results: In all patients, the percentage of patients with EGFR mutations was 52.5% (158/301). EGFR mutations were more likely to be detected in younger (<60 years old), adenocarcinoma patients, non-smokers, women, CEA≥5 μg/L and serum ferritin ≥129 μg/L for females or ≥329 μg/L for males (p <0.05). Increased serum ferritin was an independent factor for predicting EGFR mutations (odds ratio (OR)=4.593, 95% CI (2.673–7.890); P  <0.001), and an area under curve (AUC) of 0.711 was shown to predict EGFR mutations with a sensitivity of 81.7% and a specificity of 65.2% in women. Sensitivity increased to 91.1% when combining SF and CEA in all patients. SF was also an independent factor (HR=3.531, 95% CI (2.288–5.448); P <0.001) for predicting progression-free survival (PFS) of patients on EGFR-TKIs, analysed by a Cox proportional hazard model, as PFS was shorter in patients with higher SF (15.0 mo. (SF < 129 μg/L for females or <329 for males) vs 10.0 mo. (129–258 μg/L for females or 329–658 μg/L for males) vs 7.3 mo. (>258 μg/L (>258 μg/L for females or >658 μg/L for males) p<0.001).
Conclusion: SF was a significant predictor of EGFR mutation with moderate diagnostic accuracy, and combining SF and CEA increased the diagnostic sensitivity and specificity for EGFR mutations. SF was also useful for predicting survival in EGFR-TKIs.
Keywords: EGFR mutation, serum ferritin, EGFR-TKI, lung cancer, prognosis