During liver regeneration following right portal embolization the growth rate of liver metastases is more rapid than that of the liver parenchyma

Background: The relative growth rates of human liver metastases are not kno wn. The aim of this study was to determine in humans the growth rate of liv er parenchyma during regeneration and the growth rate of liver metastases d uring the same process. Methods: Among 556 patients hepatectomized for a malignant lesion, 48 under went preoperative selective right portal vein embolization to induce hypert rophy of the left lobe, Five cases were selected because a liver metastasis was present inside the regenerating left lobe, The volumes of the liver me tastasis and left lobe were measured with a three-dimensional technique on pre-embolization and post-embolization computed tomography(CT) or CT arteri al portography. The median interval between the two measurements was 34 (ra nge 28-40) days. Results: An increase occurred in the volume of the liver metastasis and the left lobe in the four patients with functionally intact liver parenchyma, bur not in the patient with an impaired parenchyma. The volumetric increase of the normal liver varied from 59 to 127 per cent, compared with 60 to 97 0 per cent for the liver metastases, The ratio between the growth rare of t he left lobe and the liver metastasis varied from 1.0 to 15.6, The growth r ates of two metastases in the left lobe of a single patient were different. Conclusion: In functionally intact Liver parenchyma, during hepatic regener ation or hypertrophy, the growth rate of metastases is more rapid that that of the Liver parenchyma, However, a wide variation in growth rate is obser ved between patients and between metastases.