title: Two cases of medullary thyroid carcinoma.
abstract: BACKGROUND
  Medullary thyroid carcinoma (MTC) is a rare thyroid malignancy but accounts for a significant mortality. We present 2 cases of MTC and review the literature regarding its management and genetic screening.
  
  
  METHODS
  Patient 1 presented after a routine health screening and subsequently was found to have a germline mutation for MEN 2A. Patient 2 presented with sweating irritability and a thyroid mass which illustrates the progressive relentless nature of the disease and highlights current imaging practice.
  
  
  METHODS
  Both patients underwent extensive surgery and received postoperatively ablative dose of radioactive iodine. Patient 2 also had a large dose I-131 MIBG therapy and further surgery.
  
  
  RESULTS
  In Patient 1, postoperative calcitonins remained elevated indicating residual disease. Patient 2 underwent further radioguided surgery; however, his postoperative calcitonins remained elevated.
  
  
  CONCLUSIONS
  MTC can be relentless. Routine genetic screening of all patients with MTC, Tc-99m pentavalent (V) DMSA imaging, near total thyroidectomy with routine central neck dissections and removal of all lymph nodes in the central neck compartment should be performed.
authors.affiliation: Department of General Medicine, Tan Tock Seng Hospital, 11 Jalan Tan Tock Seng, Singapore 308433. michelle_jong@notes.tish.gov.sg
authors.forename: M
authors.initials: M
authors.lastname: Jong
authors.forename: F X
authors.initials: FX
authors.lastname: Sundram
mesh_terms: D000328:Adult; D018276:Carcinoma, Medullary / Q000175:diagnosis* / Q000235:genetics* / Q000532:radiotherapy / Q000601:surgery; D003131:Combined Modality Therapy; D005820:Genetic Testing; D018095:Germ-Line Mutation; D006801:Humans; D008297:Male; D018813:Multiple Endocrine Neoplasia Type 2a / Q000175:diagnosis* / Q000235:genetics* / Q000532:radiotherapy / Q000601:surgery; D013964:Thyroid Neoplasms / Q000175:diagnosis* / Q000235:genetics* / Q000532:radiotherapy / Q000601:surgery