Laparoscopic Hepatectomy Results in Decreased Vegf Expression in Residual Hepatoma Cells When Compared to Open Resection

INTRODUCTION: Vascular endothelial growth factor (VEGF) is upregulated in hepatocellular carcinoma (HCC), and its level of expression in these tumors has been shown to impact tumor growth. We hypothesized that when compared to open liver resection, laparoscopic hepatectomy would result in decreased local angiogenic response in residual tumor cells.
MATERIALS AND METHODS: Right and left lobe hepatomas were induced in Buffalo rats via laparoscopic guided subcapsular injection of Morris hepatoma cells. One week later, animals were randomized to laparoscopic (LR=15) or open (OR=15) left medial hepatic lobectomy. Fourteen days after resection, the rats were sacrificed, the residual right lobe tumors were measured, and tissue was procured for RNA extraction. VEGF mRNA transcript levels were quantified with RT-PCR. VEGF serum levels were measured by ELISA prior to resection and at the time of tissue harvest.
RESULTS: None of the animals developed satellite liver lesions or distant metastases in the abdomen or thorax. Median residual tumor volume was 320mm3 in the open group, compared to 180mm3 in the laparoscopic group (p=0.164). Animals that underwent open resection had a 1.3 fold increase in VEGF mRNA transcript levels compared to the laparoscopic resection group (p=0.008). Serum VEGF levels were not significantly different between the laparoscopic and open groups at baseline (OR 23.7±12.0 pg/ml, LR 30.7±15.5 pg/ml, p=0.334) nor at the time of tissue harvest (OR 19.9±19.6, LR 26.9±34.5, p=0.549).
CONCLUSIONS: Laparoscopic hepatic resection resulted in decreased VEGF mRNA expression in residual hepatoma cells compared to open resection. Through inhibition of angiogenesis promoters in the tumor microenvironment, minimally invasive liver resection may contribute to a lower residual disease burden and ultimately lead to a lower recurrence rate.

Session: Podium Presentation

Program Number: S098