Selective portal vein ligation and embolization induce different tumoral responses in the rat liver

Background: Portal vein ligation (PVL) and portal vein embolization (PVE) are used to enhance liver volume before hepatectomy for colorectal liver metastasis (LM). Impact of such techniques on tumor growth is not well known. This experimental study aimed to assess impact of PVE and PVL on LM growth in a murine model of colorectal LM.

Methods: Single macroscopic tumor was induced by injection of 0.5 × 10(6) DHD/K12 cells under the liver capsule of BDIX rats at day 0. Multiple microscopic tumors were obtained by intra-portal injection of 1 × 10(6) cells at day 7. At day 8, rats were divided in 3 groups: PVE group (selective 70% PVE), PVL group (selective 70% PVL); control group (sham laparotomy). Rats were sacrificed at day 37 (11 in PVE, 12 in PVL, and 10 rats in control groups). Liver volume and LM volumes were assessed.

Results: Nonoccluded liver volume was larger in the PVE and PVL groups vs control group (P < .0001 and P < .0001, respectively) but showed no difference in PVE vs PVL groups (P = .08). LM volume in the occluded liver was smaller in the PVE vs control groups (P = .006) and larger in the PVL vs control groups (P = .001). LM volume in the nonoccluded liver was larger in the PVE and PVL groups vs control group (P = .010 and P = .010, respectively) but showed no difference in PVE vs PVL groups (P= .878).

Conclusion: Both PVL and PVE modify tumor growth, especially in nonoccluded lobe. These results could be of clinical importance in humans where both techniques are widely used.