ABSTRACT
Objective To develop an efficient and rapid method to synthesize 68 Ga?DOTA?TATE, and to perform PET/CT imaging on neuroendocrine tumor (NET) bearing mice and one patient. Methods 68GaCl3 was eluted by 0.05 mol/L HCl in 68 Ge?68 Ga generator, then added to pre?adjusted DOTA?TATE buffer, and heated for 15 min at 85 ℃, then filtered with 0.22 μm microfiltration membrane. The radiochemical purity and in vitro stability of 68 Ga?DOTA?TATE were analyzed with radio?HPLC. The biodistribution and PET/CT imaging on HT?29 colon cancer xenografts mice model were performed. After approved by Peking University Cancer Hospital Ethics Committee, a case of NET patient received 148 MBq 68 Ga?DOTA?TATE intravenous?ly, followed by a whole?body scan at 60 min post?injection. Results 68 Ga?DOTA?TATE was prepared in high radiochemical purity (>98%) and with specific activity of 55 GBq/μmol in 25 min. The tracer showed excellent in vitro stability and no acute toxicity. PET/CT imaging on mice model showed positive uptake in tumor tissues. PET/CT imaging on one NET patient showed positive uptake of 68 Ga?DOTA?TATE in primary and metastases lesions. Conclusions A rapid, high radiolabeling yield and high specific activity method to prepare 68 Ga?DOTA?TATE is established. 68 Ga?DOTA?TATE could be specifically uptaken by somatostatin receptor ( SSTR) positive NET with high affinity. It could serve as a useful tool for early diagnosis of SSTR positive NET and has clinical prospective for somatostatin?mediated targeting therapy.