Correlation of Glucose Transporter-1 Expression With Uptake of 18F-Fluorodeoxyglucose Positron Emission Tomography in Thyroid Papillary Carcinoma

Lee, Ja Hyun; Pae, So Young; Park, Eun Hee; Koo, Hea Soo; Pai, Moon Sun; Chung, Sung Min; Kim, Han Su

Abstract

Backgroud and Objectives: 18F-FDG Positron emission tomography (18F-FDG PET) is a noninvasive diagnostic tool for many kinds of human cancer, where glucose transporter-1 (Glut-1) acts as a main transporter in the uptake of 18F-FDG in cancer cells. The object of this study is to assess the expression of Glut-1 in human papillary carcinoma and the relationship between the expression and the uptake of 18F-FDG PET.
SUBJECTS AND METHOD
We evaluated 30 patients diagnosed as papillary carcinoma. Tumor sizes were measured and Glut-1 expression rate (ER), expression intensity (EI) and total expression score (ES) were analyzed. 18F-FDG PET was performed in 19 patients and standardized uptake value (SUV) was measured in each case. The correlations between ER and SUV, ES and SUV, tumor sizes and SUV, ER and tumor sizes were analyzed statistically.
RESULTS
96.7% (29/30) of tumors were Glut-1 positive, the mean ER was 67.42+/-22.89% and the mean ES 131.8+/-71. Tumor cells showed higher expression of Glut-1 than normal thyroid tissue. 18F-FDG uptake was positive in 81% (17/21) of solitary thyroid papillary carcinoma and negative in 19% (4/21). The average SUV of the PET positive group was 6.75+/-4.8, ER 71.25 +/-20.6% and ES 134.68+/-51.4. The average size of PET positive tumors was 3.37+/-2.94 cm2 and that of negative tumors was 0.43+/-0.45 cm2. Both ER and ES of Glut-1 were correlated with SUV significantly. The size and SUV were also correlated significantly. But the size and ER were not correlated significantly.
CONCLUSION
Thyroid papillary carcinoma has high ER of Glut-1 and there is a positive correlation between Glut-1 expression and the uptake of 18F-FDG PET. The size of tumor can also affect the 18F-FDG uptake. But there is no correlation between the size and Glut-1 expression and further studies are needed to find the mechanisms and to decide the cut-off value.