两种正电子发射型计算机断层扫描显像对性质不明的肝脏占位的诊断

目的观察两种不同的正电子发射型计算机断层扫描（PET）显像对常规检查无法明确的肝脏占位的诊断价值。方法在489例临床诊断为肝脏占位的患者中,收集经各种常规检查无法定性,且有条件行两次PET检查的患者15例。所有患者均在手术前接受^11C-乙酸盐-PET和^18F-去氧葡萄糖（FDG）-PET检查。结果病理证实恶性病变13例,良性病变2例。在13例恶性病变中,^11C-乙酸盐-PET提示恶性10例,良性3例;^18F-FDG-PET提示恶性9例,良性4例;在2例良性病变中,^11C-乙酸盐-PET提示恶性和良性各1例;^18F-FDG-PET提示恶性和良性也各1例。对于高中分化肝细胞肝癌,^11C-乙酸盐-PET所显示的敏感性（100％）高于^18F-FDG—PET的敏感性（20％）;对于低中分化的肝细胞肝癌,^18F-FDG的敏感性高。结论在常规检查不能明确肝占位性质时,有条件的情况下应用两种PET示踪剂能提高相关的诊断率,两种示踪剂联合应用还可提示肿瘤的分化程度,对于手术方式的选择有一定的指导意义。

The values of (11)C-acetate and (18)F-fluorodeoxyglucose positron emission tomography in diagnosis of indefinite liver masses

OBJECTIVE: To evaluate the values of the two tracers of positron emission tomography (PET) in the liver masses not definitely diagnosed by routine examinations. METHODS: Fifteen patients with liver masses of indefinite diagnosis after serum tests and common imaging examinations underwent PET with both (11)C-acetate and (18)F-fluorodeoxyglucose (FDG). The results were compared. After the PET all 15 patients were subjected to surgery. RESULTS: Pathological examination showed that 13 of the 15 patients were confirmed as malignant liver lesions and the other 2 as benign. Within the 13 malignant liver lesions, (11)C-acetate-PET suggested malignancy in 10 cases, and benignancy in 3 cases. And (18)F-FDG-PET suggested malignancy in 9 cases and benignancy in 4 cases. In the two benign cases, both (11)C-acetate-PET and (18)F-FDG-PET showed one malignant liver lesion and one benign liver lesion. (11)C-acetate-PET showed a high sensitivity (100%) for the well-differentiated tumors, and (18)F-FDG-PET showed a high sensitivity for the poorly-differentiated tumors. CONCLUSION: The diagnostic accuracy for liver lesions may be improved by the two tracers of PET when the lesions can not be definitely diagnosed by routine examinations and at the same time when the patients are able to afford two PET examinations. They may also imply the cell-differentiation of the liver masses, and be helpful for selecting the treatment means for the patients.