[Delayed Tc-99m-PMT imaging in the specific diagnosis of hepatocellular carcinoma]

The results of Tc-99m-PMT imaging on 100 patients with various malignant and benign hepatic diseases verified histologically (73 hepatocellular carcinoma, 3 liver cell adenoma, 1 cholangiocarcinoma, 5 metastatic liver carcinoma, 2 liver cyst, 12 hemangioma, 1 fatty degeneration, 1 liver regeneration, 1 postoperative liver fibrosis and 1 liver cirrhosis) are reported. All lesions appeared as decreased radioactivity or "cold" defect region on early Tc-99m-PMT imaging, rendering it valuable for the diagnosis of tumor localization. In 92 (95.8%) of the 96 patients with various hepatic tumors and 25 (86.2%) of the 29 patients with small hepatocellular carcinoma (less than 5 cm), the tumors were localized by early Tc-99m-PMT imaging. In 14 of the 73 patients with established hepatocellular carcinoma, the tumors gave greater radioactivity than that of the surrounding liver tissues, whereas in 31 patients the radioactivity of the tumor equalled the normal liver on delayed Tc-99m-PMT imaging (positive rate 61.6%). There was no significant difference between the positive rates of serum AFP level and the tumor size shown by delayed Tc-99m-PMT imaging in hepatocellular carcinomas. The radioactivity in 3 liver cell adenoma patients was similar to the gallbladder. No false positive result was seen in the other malignant and benign hepatic tumors. This study indicates that delayed Tc-99m-PMT imaging is highly specific in the diagnosis of hepatocellular carcinoma.