EGFR and neoplasm: Interestingly, in 38% (8/21) of cases, examined both the primary tumour and related metastasis were EGFR negative (staining present in less than 5% of tumour cells or staining intensity of 0) and 48% (10/21) patients had discordance in the expression of wtEGFR in the primary tumours and related metastasis.