Serum human epididymis protein 4 (HE4) may be a better tumor marker in early lung cancer

•Serum HE4 was one of the biomarkers with the highest sensitivity and specificity to compare with others.•Serum HE4 was the best biomarker both in adenocarcinoma and squamous carcinoma.•The combination of proGRP, NSE and HE4 would determine the histological type of lung cancer with a high accuracy of 93.8%.