However, several types of tumors (cervical, liver, colorectal, prostate invasive ductal breast, small cell lung cancer and lung squamous cell carcinoma) showed similar CD73 expression level compared to the level in matched normal tissues (P > 0.05) (Additional file 1: Figures S3, S4, S5, S9, S10, S11, S12, S14, S18, S19). This evidence concerns the gene NT5E and squamous cell lung carcinoma.