CEACAM5 and medullary thyroid gland carcinoma: The possibility of using CEA as a cancer indicator to predict the severity of the disease has been studied in a retrospective study published in 2018, where preoperative and postoperative calcitonin and CEA values were measured in 33 patients who underwent total thyroidectomy with central and/or lateral lymph node dissection for MTC during the period 2003–2016.