Acceleration of primary liver tumor growth rate in embolized hepatic lobe after portal vein embolization

Background: Portal vein embolization ( PVE) is now widely accepted as a useful preoperative procedure in selected patients undergoing extended hepatectomy. However, the effect of PVE on the growth of liver tumors has not been fully elucidated. Purpose: To retrospectively evaluate the effects of PVE on the growth of liver tumors in the embolized lobes. Material and Methods: Eight patients with a primary liver tumor, six hepatocellular carcinomas ( HCC) and two cholangiocellular carcinomas ( CCC), were studied. The growth rates of the tumors in the embolized lobes and non- embolized liver parenchyma were calculated using the computed tomography ( CT) volume values at the time of tumor identification, and before and after PVE. Result: The median tumor growth rate was 0.59 cm(3)/ day ( range 0.22 - 6.01 cm(3)/ day) before PVE and 2.37 cm(3)/ day ( range 0.29 - 13.97 cm(3)/ day) after PVE ( P=0.018). The tumor growth acceleration ratios ranged from 1.50 to 7.46 ( median 2.65) in the six HCCs, and were 1.00 and 1.32 in the two CCCs. There was no apparent correlation between the tumor growth rate after PVE and the growth rate of non- embolized liver parenchyma ( median 6.00 cm(3)/ day, range 1.24 - 11.0 cm(3)/ day). Conclusion: Liver tumor growth in an embolized lobe accelerates after PVE, in patients with HCC.