title: Lack of elevated serum carcinoembryonic antigen and calcitonin in medullary thyroid carcinoma.
abstract: OBJECTIVE
  Medullary thyroid carcinoma (MTC) originates from C-cells. A wide variety of tumor markers including calcitonin (CT), carcinoembryonic antigen (CEA), and chromogranin A are produced by MTC. Surgery remains the only potentially curative therapy, and early detection of the primary remains the most important prognostic factor for a positive outcome for the patient. The following case concerns a 50-year-old woman with histologically proven MTC, who completely lacked serum elevation of both CT and CEA.
  
  
  METHODS
  We performed a total thyroidectomy with lymphadenectomy in the central compartment. Histologic sections were stained for CT, CEA, and chromogranin A. Additionally we examined the patient's blood for mutations in the RET proto-oncogene.
  
  
  RESULTS
  Serum CT and CEA were below the detection level in the serum. The tumor showed weak staining for CT, but strong staining for CEA and chromogranin A. Sequencing of the RET-proto-oncogene revealed no mutations. Five years after the operation, the patient remains well and shows no signs of tumor recurrence.
  
  
  CONCLUSIONS
  We hereby report of a patient with neither plasma elevation of CT nor CEA. From the clinical standpoint, it is important to determine how this subgroup of MTC should be followed because CT and CEA are of no clinical use.
authors.affiliation: Department of General and Transplantation Surgery, University Hospital Essen, Essen, Germany. maximilian.bockhorn@uni-essen.de
authors.forename: Maximilian
authors.initials: M
authors.lastname: Bockhorn
authors.forename: Andreja
authors.initials: A
authors.lastname: Frilling
authors.forename: Stephan
authors.initials: S
authors.lastname: Rewerk
authors.forename: Marc
authors.initials: M
authors.lastname: Liedke
authors.forename: Olaf
authors.initials: O
authors.lastname: Dirsch
authors.forename: Kurt W
authors.initials: KW
authors.lastname: Schmid
authors.forename: Christoph E
authors.initials: CE
authors.lastname: Broelsch
mesh_terms: D002116:Calcitonin / Q000097:blood* / Q000378:metabolism; D002272:Carcinoembryonic Antigen / Q000097:blood* / Q000378:metabolism; D018276:Carcinoma, Medullary / Q000097:blood* / Q000378:metabolism; D053379:Chromogranin A; D002864:Chromogranins / Q000378:metabolism; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D008875:Middle Aged; D000090063:Proto-Oncogene Mas; D013964:Thyroid Neoplasms / Q000097:blood* / Q000378:metabolism
chemical_list: D002272:Carcinoembryonic Antigen; D053379:Chromogranin A; D002864:Chromogranins; C000715470:MAS1 protein, human; D000090063:Proto-Oncogene Mas; D002116:Calcitonin