Evaluation of the blood supply and efficacy of transcatheter arterial chemoembolization for patients with liver metastasis using 18F-fluorodeoxyglucose positron emission tomography/computed tomography.

Our study aims to evaluate the efficacy of transcatheter arterial chemoembolization in the treatment of patients with liver metastasis using integrated 18F-fluorodeoxyglucose positron emission tomography/computed tomography. A total of 97 liver metastasis patients treated by transcatheter arterial chemoembolization were enrolled in this study. The 18F-fluorodeoxyglucose positron emission tomography/computed tomography images of liver metastasis patients were collected before and after transcatheter arterial chemoembolization treatment. The efficacy of transcatheter arterial chemoembolization for the treatment of liver metastasis was evaluated according to the revised Response Evaluation Criteria in Solid Tumors guidelines. The receiver operating characteristic curve analysis was used to determine cut-off values of 18F-fluorodeoxyglucose positron emission tomography parameters (Tsuvmax, Tsuvmax/Lsuvmax, and Tsuvmax/Lsuvmean) for predicting the efficacy of transcatheter arterial chemoembolization. Progression-free survival and the incidence of postoperative complications were compared. Correlation of Tsuvmax, Tsuvmax/Lsuvmax, and Tsuvmax/Lsuvmean with blood supply and lipiodol deposition in the lesion was analyzed. Among three 18F-fluorodeoxyglucose positron emission tomography parameters, the receiver operating characteristic analysis showed that Tsuvmax/Lsuvmax with a cut-off value of 3.56 was the best predictor of transcatheter arterial chemoembolization efficacy. According to the cut-off value of Tsuvmax/Lsuvmax, liver metastasis patients were divided into the Tsuvmax/Lsuvmax ≤ 3.56 and Tsuvmax/Lsuvmax > 3.56 groups. Compared with the Tsuvmax/Lsuvmax > 3.56 group, the Tsuvmax/Lsuvmax ≤ 3.56 group showed a longer progression-free survival and a lower incidence of postoperative complications. The Tsuvmax, Tsuvmax/Lsuvmax, and Tsuvmax/Lsuvmean in the lesion with abundant blood supply were significantly lower than those in peripheral liver parenchyma, while the Tsuvmax, Tsuvmax/Lsuvmax, and Tsuvmax/Lsuvmean in the lesion with lack of blood supply were significantly higher than those in peripheral liver parenchyma. Spearman correlation analysis indicated that lipiodol deposition in the lesion was positively correlated with the Tsuvmax, Tsuvmax/Lsuvmax, and Tsuvmax/Lsuvmean. The Tsuvmax/Lsuvmax of 18F-fluorodeoxyglucose positron emission tomography/computed tomography may be a good tool for predicting the blood supply and efficacy of transcatheter arterial chemoembolization for patients with liver metastasis.

[Spiral computed tomography images of extraluminal type gastric stromal tumors].

OBJECTIVE: To evaluate the diagnostic value of spiral CT and its reconstruction techniques in the diagnosis of extraluminal type gastric stromal tumors. METHODS: The data of spiral CT performed 1 week before operation of 17 extraluminal type cases, 11 males and 6 females, aged 35.5 (13-67), from 33 patients of gastric stromal tumors proved by pathology and immunohistochemistry, were analyzed retrospectively. RESULTS: The accuracy rates of level diagnosis and qualitative diagnosis of extraluminal type gastric stromal tumor by spiral CT were 88.2% and 82.4% respectively. The main CT manifestations included: (1) extraluminal mass connected with the gastric wall, with round or lobulated margin and characteristic horn-like appearance and direct invasion, more than 5.0 cm in diameter; (2) inhomogeneous density of mass, including mild to moderate uneven enhancement in artery phase and obvious enhancement in vein and delay phase in 15 cases, and obvious enhancement in artery phase and decrease of enhancement in portal vein phases in 2 cases. (3) Irregular niches and sinus in the margins of the intraluminal masses (n = 11) and unclear border of the masses and invasion into nearby structures (n = 9); (4) connection of the tumor and stomach wall by broad boundary or failure to distinguish the tumor and stomach wall; and (5) invasion to the surrounding tissues and organs as a sign of malignant tumors. CONCLUSION: Spiral CT and its reconstruction techniques have important value in level diagnosis and qualitative diagnosis of extraluminal type gastric stromal tumors.