[Biodistribution and positron emission tomography imaging of 11C-acetate in murine model of lung carcinoma].

Objective: To investigate the biodistribution and positron emission tomography (PET) imaging of 11C-acetate (11C-AC) in a murine model of pulmonary carcinoma, and to evaluate the use of 11C-AC for diagnosis of malignant tumor.

Methods: A total of 30 T739 mice underwent subcutaneous injection of mouse pulmonary adenocarcinoma cells of the line LA-795 to establish adenocarcinoma models and then were randomly divided into five equal groups. Four groups underwent intravenous injection of 11C-acetate through the caudal vein, killed 5, 10, 20, and 30 minutes later respectively, underwent PET, and then their organs and tumors were isolated. The mice in the control group underwent injection of 11F-fluorodeoxyglucose (18F-FDG) and were killed 60 min later. The biodistribution of 11C-AC and that of 18F-FDG were measured with well-gamma detector. The ratios of the levels of percentage activity of injection dose per gram of tissue between the tumor and normal tissues (T/NT ratios), were calculated.

Results: In the biodistribution study of 11C-AC, considerable radioactive uptake of tumor was observed, and much radioactivity was showed in kidney, liver, and spleen. The ratios of tumor/blood, tumor/muscle, and tumor/lung were all above 2. 0. The tumor PET images with 11C-AC as tracer were as clear as that with 18F-FDGas tracer. The 11C-AC standard uptake value (SUV) of the tumors was 2.8 +/- 0.8, significantly lower than that of 18F-FDG (5.3 +/- 1.6, P <0.01).

Conclusion: 11C-AC can be used in PET imaging of pulmonary malignancy. The optimized imaging acquisition time point is 20 min after injection. It may become a complementary tracer in the cases with unsatisfying 18F-FDG images.