Medullary thyroid carcinoma presenting with an initial CEA elevation

Background: Carcinoembryonic antigen (CEA) is a tumour marker commonly associated with gastrointestinal malignancy. Patients presenting with an elevated CEA will therefore often undergo extensive investigations in order to elucidate an underlying gastrointestinal malignancy that may not be clinically apparent. However the GI tract is not the only source of CEA elevation. Methods: We present a series of patients presenting with raised CEA levels that were initially investigated for a gastrointestinal cause, but after work up were detected to have medullary thyroid cancer. Results: Four patients with raised CEA were evaluated for a gastrointestinal cause for the elevation. We discuss the non gastrointestinal causes for an elevated CEA. Conclusion: The paper highlights that in patients presenting with an elevated CEA, in whom a gastrointestinal cause has been ruled out, a tumour of neuroendocrine origin needs to be considered as a cause for the elevated CEA.