CEACAM5 and neoplasm: A further aim of the study was to determine whether preoperative parameters such as age, sex, preoperative bCtn, sCtn and carcinoembryonic antigen (CEA) levels, cN status and number of involved neck regions on DOPA PET/CT, and the postoperative ratio of resected to metastatic LNs on histology are predictive of postoperative tumour persistence or recurrence.