ALK and lung cancer: Based on these findings, this case was staged as cTxNxM1b, IV A according to the 8th edition of tumor, node, and metastasis staging system for lung cancer.[6] Liquid biopsy showed wild-type EGFR, human epidermal growth factor receptor 2 and vascular endothelial growth factor, followed by negative echinoderm microtubule-associated protein-like 4-anaplastic lymphoma kinase (ALK) fusion gene.