B Academy of Molecular Imaging, 2009 Published Online: 1 December 2009 DOI: 10.1007/s11307-009-0276-2 Mol Imaging Biol (2010) 12:547Y553 RESEARCH ARTICLE The Prognostic Value of 2-Deoxy-2-[18F]Fluoro- D-Glucose Positron Emission Tomography in Patients With Suspected Residual or Recurrent Medullary Thyroid Carcinoma Trond Velde Bogsrud, 1 Dimitrios Karantanis, 2 Mark A. Nathan, 2 Brian P. Mullan, 2 Gregory A. Wiseman, 2 Jan L. Kasperbauer, 3 Carl C. Reading, 4 Trine Björo, 5 Ian D. Hay, 6 Val J. Lowe 2 1 Division of Nuclear Medicine, Department of Radiology, The Norwegian Radium Hospital, Oslo University Hospital, Oslo, Norway 2 Division of Nuclear Medicine, Department of Radiology, Mayo Clinic, 200 First St SW, Rochester, MN 55905, USA 3 Department of Otorhinolaryngology, Mayo Clinic, 200 First St SW, Rochester, MN 55905, USA 4 Division of Ultrasonography, Department of radiology, Mayo Clinic, 200 First St SW, Rochester, MN 55905, USA 5 Department of Clinical Biochemistry, The Norwegian Radium Hospital, Oslo University Hospital, Oslo Norway 6 Division of Endocrinology, Department of Internal Medicine, Mayo Clinic, 200 First St SW, Rochester, MN 55905, USA Abstract Purpose: To explore the prognostic value of 2-deoxy-2-[18F]fluoro-D-glucose (FDG) positron emission tomography (PET) in patients with suspected residual or recurrent medullary thyroid carcinoma (MTC). Procedures: This retrospective study included all patients with MTC examined with FDG-PET at Mayo Clinic, Rochester, Minnesota, from October 1999 to March 2008. The PET results were compared with other imaging studies and clinical findings, including carcinoembryonic antigen and calcitonin levels. Results: Twenty-nine patients with MTC were included. PET was positive in 14 patients, with follow-up information for 11; six died from metastatic disease, four had disease progression, and one remained in stable condition. PET was negative in 15 patients, with follow-up for 12; one had recurrent disease, and 11 had no evidence of clinical disease. Calcitonin doubling time was shorter for PET-positive than for PET-negative patients. Conclusion: FDG-PET has high prognostic value in patients with suspected residual or recurrent MTC. Key words: 2-deoxy-2-[18F]fluoro-D-glucose, FDG, Medullary thyroid carcinoma, PET, PET/CT, Positron emission tomography Abbreviations: CEA, Carcinoembryonic antigen; CT, Computed tomographic, computed tomography; FDG, 2-deoxy-2-[18F]fluoro-D-glucose; FNAB, Fine-needle aspiration biopsy; FSE, Fast spin-echo; MIP, Maximum intensity projection; MRI, Magnetic resonance imaging; MTC, Medullary thyroid carcinoma; PET, Positron emission tomography; SD, Standard deviation; SUV max , Maximum standard uptake value Introduction M edullary thyroid carcinoma (MTC) is a rare cancer arising from the parafollicular cells or calcitonin cells (C cells), which are organized between the basal layer and the Correspondence to: Val J. Lowe; e-mail: vlowe@mayo.edu