Correlation of 4′-[methyl-11C]-thiothymidine uptake with Ki-67 immunohistochemistry and tumor grade in patients with newly diagnosed gliomas in comparison with 11C-methionine uptake
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A novel radiopharmaceutical, 4′-[methyl-11C]thiothymidine (11C-4DST), has been developed as an in vivo cell proliferation marker based on the DNA incorporation method. The purpose of this study was to evaluate 11C-4DST uptake in patients with newly diagnosed glioma and to correlate the results with proliferative activity and tumor grade, in comparison with l-[methyl-11C]-methionine (11C-MET).
Investigations of 11C-4DST and 11C-MET PET/CT were performed retrospectively in 23 patients with newly diagnosed glioma. The maximum standardized uptake value (SUVmax) for tumor (T) and the mean SUV for normal contralateral hemisphere (N) were calculated, and the tumor-to-normal (T/N) ratio was determined. Metabolic tumor volume (MTV) was defined as the volume with a threshold of 40 % of the SUVmax. Proliferative activity as indicated by the Ki-67 index was estimated in tissue specimens.
Of 23 gliomas examined, 11C-4DST PET/CT and 11C-MET PET/CT detected 20 and 22, respectively. Linear regression analysis between 11C-4DST and 11C-MET indicated a weak correlation for SUVmax (r = 0.54, P < 0.008), for T/N ratio (r = 0.56, P < 0.006), and for MTV (r = 0.60, P < 0.003). Linear regression analysis indicated a weak correlation between 11C-4DST and Ki-67 index for SUVmax (r = 0.46, P < 0.03), for T/N ratio (r = 0.43, P < 0.05), and for MTV (r = 0.68, P < 0.001) and between 11C-MET MTV and Ki-67 index (r = 0.43, P < 0.04). Using 11C-4DST, there was a significant difference in SUVmax between grades II and IV (P < 0.03) and in MTV between grades II and IV (P < 0.009) and grades III and IV (P < 0.02). Using 11C-MET, there was a significant difference in SUVmax (P < 0.009) and T/N ratio (P < 0.02) between grades II and IV and in MTV between grades II and IV (P < 0.03) and grades III and IV (P < 0.02).
11C-4DST PET/CT is feasible for imaging of brain gliomas, as well as 11C-MET PET/CT. Especially, it showed the highest correlation coefficient between 11C-4DST MTV and Ki-67 index in newly diagnosed gliomas.
Keywords11C-4DST 11C-MET PET Glioma Proliferation
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Conflict of interest
None of the authors have any potential conflicts of interest relevant to this article to report.
- 20.Ito K, Yokoyama J, Miyata Y, Toyohara J, Okasaki M, Minamimoto R, et al. Volumetric comparison of positron emission tomography/computed tomography using 4′-[methyl-11C]-thiothymidine with 2-deoxy-2-18F-fluoro-d-glucose in patients with advanced head and neck squamous cell carcinoma. Nucl Med Commun. 2015;36:219–25.CrossRefPubMedGoogle Scholar