간암환자에 있어서 ¹¹C-Acetate와 ¹⁸F-FDG PET/CT 검사의 당일 검사법과 양일 검사법의 비교

Comparison of One-day and Two-day Protocol of ¹¹C-Acetate and ¹⁸F-FDG Scan in Hepatoma

Purpose: ¹¹C-Acetate PET/CT is useful in detecting lesions that are related to livers in the human body and leads to a sensitivity of 87.3%. On the other hand, ¹⁸F-FDG PET/CT has a sensitivity of 47.3% and it has been reported that if both ¹⁸F-FDG and ¹¹C-Acetate PET/CT are carried out together, their cumulative sensitivity is around 100%. However, the normal intake of the pancreas and the spleen in ¹¹C-Acetate PET/CT can influence the ¹⁸F-FDG PET/CT leading to an inaccurate diagnosis. This research was aimed at the verification of the usefulness of how much influence these two radioactive medical supplies can cause on the medical images through comparative analysis between the one-day and two-day protocol. Materials and Methods: This research was carried out based on 46 patients who were diagnosed with liver cancer and have gone through the PET/CT (35 male, 11 female participants, average age: 54±10.6 years, age range: 29-69 years). The equipment used for this test was the Biograph TruePoint40 PET/CT (Siemens Medical Systems, USA) and 21 participants who went through the one-day protocol test were first given the ¹¹C-Acetate PET/CT and the ¹⁸F-FDG PET/CT, the latter exactly after one hour. The other 25 participants who went through the two-day protocol test were given the ¹¹C-Acetate PET/CT on the first day and the ¹⁸F-FDG PET/CT on the next day. These two groups were then graded comparatively by assigning identical areas of interest of the pancreas and the spleen in the ¹⁸F-FDG images and by measuring the Standard Uptake Value (SUV). SPSS Ver.17 (SPSS Inc., USA) was used for statistical analysis, where statistical significance was found through the unpaired t-test. Results: After analyzing the participants’ medical images from each of the two different protocol types, the average±standard deviation of the SUV of the pancreas carried out under the two-day protocol were as follows: head 1.62±0.32 g/mL, body 1.57±0.37 g/mL, tail 1.49±0.33 g/mL and the spleen 1.53±0.28 g/mL. Whereas, the results for participants carried out under the one-day protocol were as follows: head 1.65±0.35 g/mL, body 1.58±0.27 g/mL, tail 1.49±0.28 g/mL and the spleen 1.66±0.29 g/mL. Conclusion: It was found that no statistical significant difference existed between the one-day and two-day protocol SUV in the pancreas and the spleen (p<0.05), and nothing which could be misconceived as false positive were found from the PET/CT medical image analysis. From this research, it was also found that no overestimation of the SUV occurred from the influence of ¹¹C-Acetate on the ¹⁸F-FDG medical images where those two tests were carried out for one day. This result was supported by the statistical significance of the SUV of measurement. If ¹¹C-Acetate becomes commercialized in the future, the diagnostic ability of liver diseases can be improved by ¹⁸F-FDG and one-day protocol. It is from this result where tests can be accomplished in one day without the interference phenomenon of the two radioactive medical supplies and furthermore, could reduce the waiting time improving customer satisfaction.