Evaluation of fluorodeoxyglucose-positron emission tomographic scanning and its association with glucose transporter expression in medullary thyroid carcinoma and pheochromocytoma: a clinical and molecular study.
BACKGROUND
Imaging of metastatic sites of medullary thyroid carcinoma (MTC) is successful in less than 60% of cases of residual or recurrent disease. Positron emission tomography (PET) with [18F]fluoro-2-deoxy-D-glucose (FDG) takes advantage of the fact that malignant tumors are capable of increased uptake and use of glucose, which is mediated by the members of the glucose transporter family of proteins (GLUT 1 through GLUT 5).


METHODS
FDG-PET images of 10 patients with recurrent or persistent MTC after primary operation were compared with images by computed tomography or magnetic resonance imaging. Identified metastatic lesions were assessed by intraoperative findings and pathology reports. Expression of GLUT 1 through GLUT 5 was examined by Western blot analysis of tumor tissue from eight of the patients evaluated and an additional panel of 10 MTCs and seven pheochromocytomas.


RESULTS
FDG-PET identified 31 foci of FDG accumulation in 10 patients, and 16 of these metastatic sites were resected and confirmed by histologic analysis. Only 11 foci were demonstrated by computed tomographic or magnetic resonance imaging. None of the glucose transporters examined displayed significant expression. Two pheochromocytomas were successfully imaged by FDG-PET.


CONCLUSIONS
FDG-PET imaging can be useful in the localization of cervicomediastinal MTC metastases and pheochromocytoma. The increased glucose uptake in these tumors, as evidenced by FDG-PET, does not appear to be attributable to the expression of the glucose transporter proteins GLUT 1 through GLUT 5.
Musholt
T J
TJ
Department of Surgery, Washington University School of Medicine, St. Louis, MO 63110, USA.
Musholt
P B
PB
Dehdashti
F
F
Moley
J F
JF
D000293:Adolescent; D000310:Adrenal Gland Neoplasms / Q000737:chemistry / Q000000981:diagnostic imaging*; D000328:Adult; D015153:Blotting, Western; D018276:Carcinoma, Medullary / Q000737:chemistry / Q000000981:diagnostic imaging*; D002648:Child; D005260:Female; D019788:Fluorodeoxyglucose F18; D051272:Glucose Transporter Type 1; D051275:Glucose Transporter Type 4; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D009004:Monosaccharide Transport Proteins / Q000032:analysis*; D009124:Muscle Proteins; D010673:Pheochromocytoma / Q000737:chemistry / Q000000981:diagnostic imaging*; D049268:Positron-Emission Tomography; D013964:Thyroid Neoplasms / Q000737:chemistry / Q000000981:diagnostic imaging*
D051272:Glucose Transporter Type 1; D051275:Glucose Transporter Type 4; D009004:Monosaccharide Transport Proteins; D009124:Muscle Proteins; C495677:SLC2A1 protein, human; C495692:SLC2A4 protein, human; D019788:Fluorodeoxyglucose F18