ROS new function for ECT imaging observation of sustained 99mTC-labeled cytarabine in liver cancer patient with hydrogen peroxide.

e15568 Background: To investigate the sustaining time of 99mTc labeled cytarabine in the tumor of liver cancer patients by ROS under ECT imaging instrument. Methods: A liver cancer patient with 2 lesions in the liver was enrolled in this study. After obtaining informed consent and excluding relevant contraindications, two tumors in the liver of the patient were guided by single photon emission computed tomography (ECT). Injecting the drug, the tumor was injected with 99m TC-labeled cytarabine solution as control, the tumor was injected with 99m TC-labeled cytarabine + hydrogen peroxide solution (ROS) as experimental, and the two tumor masses were detected by ECT imaging, with an intensity of 1h as background. The drug retention rate was calculated by caculated of deduction of the baseline (minus background) at 1h, 3h, and 23h. Results: The patient was detected by ECT on the right laid down position. The area of the region of interest was 679 account by Gama detector, and the background level of the liver was 494 account. The acquisition time was about 400 seconds as a standard acquisition. The ECT imaging showed that the labeling rate of 99mTC-labeled cytarabine was about 100%. The drug of 99mTC-labeled cytarabineretentionrates in tumor lesions with ROS at 1 hours, 3 hours, and 23 hours were 97.83%, 81.63%, and 60.72%, respectively; the drug retention rates in tumor lesions without ROS at 1 hours, 3 hours, and 23 hours were 44.74%, 15.87%, and 0, respectively. Conclusions: The ROS can hold drug in the tumor long time after the intratumoral injection of drugs with ROS whichoxidant with the extracellular matrix and interstitial of the tumor to cause degeneration and deformation so that drug of Ara-C sustaining in tumor for a long time, and the tumor cells are also degenerated and necrotic and died, so that high concentrations of cytarabine are embedded between the denatured tumor tissues and cells. The drug slowly released from the inside to the outside to kill tumor cells. IT is further confirmed that the ROS is a sustained release agent intratumorally injection and it can significantly increase the residence time of 99mTc-labeled cytarabine in the tumor, prolong the drug action time of cytarabine, and improve the effect of killing tumor cells.