Yuka Yamamoto MD, PhD, Presenter: Nothing to Disclose

Yukito Maeda, Abstract Co-Author: Nothing to Disclose

Yoshihiro Nishiyama MD, Abstract Co-Author: Nothing to Disclose

Although 3'-deoxy-3'-18F-fluorothymidine (FLT) has been used for imaging cell proliferation with PET, it is not incorporated into DNA. A new tracer, 4'-[methyl-11C]-thiothymidine (4DST), has been developed as an in vivo cell proliferation marker based on the DNA incorporation method. The purpose of this study was to investigate the feasibility of 4DST PET, compared with FLT PET, for the detection of head and neck cancer.

Five patients with head and neck squamous cell carcinoma were examined with both 4DST PET and FLT PET. Tumor lesions were identified as areas of focally increased uptake, exceeding that of the surrounding normal tissue. PET results were evaluated by visual and semi-quantitative analyses. For semi-quantitative analysis, the maximal standardized uptake value (SUV) was determined by region-of-interest analysis.

4DST uptake in tumors peaked before 3 minutes and reached a constant level at approximately 10 minutes after injection. Physiological uptake in salivary glands of 4DST was stronger than that of FLT. Both 4DST PET and FLT PET detected all head and neck tumors. There was no significant difference between the mean (±SD) value of SUV in the tumor using 4DST PET (8.00±5.03) and FLT PET (10.63±10.29). A significant correlation was observed between SUV in the tumor on 4DST PET and FLT PET (r=0.959, P<0.01).

These preliminary results indicate that 4DST PET is a potentially useful tracer for proliferation imaging in head and neck cancer.

4DST PET may be a potentially useful tracer for proliferation imaging in head and neck cancer.

Yamamoto, Y, Maeda, Y, Nishiyama, Y, 4’-[methyl-11C]thiothymidine (4DST) PET for Proliferation Imaging in Head and Neck Cancer: Comparison with 18F- FLT PET.  Radiological Society of North America 2013 Scientific Assembly and Annual Meeting, December 1 - December 6, 2013 ,Chicago IL. http://archive.rsna.org/2013/13019723.html