201Tl per-rectal scintigraphy in primary hepatocellular carcinoma.

The results of 201Tl per-rectal scintigraphy in 10 patients with primary hepatocellular carcinoma (HCC) were presented together with the findings from contrast angiography, computed tomography and ultrasonography. 201Tl accumulation within the tumour was seen in seven of ten patients. This accumulation was thought to be due to 201Tl supply not from the portal vein but from the hepatic artery since significantly high heart to liver uptake (H/L) ratio from 0.71 to 1.21 and clear visualization of the heart and kidneys, indicating the presence of abundant portal-to-systemic shunting, were observed. Another three patients showed negative 201Tl accumulation within the tumour and near-normal H/L ratios from 0.32 to 0.47 which indicates little portal-to-systemic shunting. This finding reveals the evidence of the lack of 201Tl supply to the tumour from the portal vein. It seems that HCC does not receive any significant amount of blood flow from the portal system.