ERBB4 quantification showed significantly higher ERBB4 expression in metastatic lesions versus patient-matched primary tumours (Fig 8; p < 0.05), with 78.9% of patients having high (strong/moderate) ERBB4 expression in metastatic lesions compared to 42.1% in the primary tumours (Fig 8; p < 0.05). Here, ERBB4 is linked to neoplasm.