Administration of anti-vascular endothelial growth factor antibody following hepatectomy does not inhibit remnant liver regeneration or growth of remnant metastases.

ABSTRACT

In addition to the use of chemotherapeutic agents for the prevention of multiple liver metastases from colorectal cancer, the anti-vascular endothelial growth factor (VEGF) antibody, bevacizumab, is often used, and its effectiveness has been established. By contrast, it has been reported that the use of bevacizumab prior to or following surgery delays wound healing or liver regeneration. In this study, we investigated whether the administration of bevacizumab following hepatectomy inhibits remnant liver regeneration or the growth of remnant metastases. Mice were partially hepatectomized (31% of the liver was removed), transplanted with the murine colorectal cancer cell line, CT26, in the remnant lobe, and intraperitoneally injected with bevacizumab (4 mg/kg) for a total of 6 times. Serum VEGF levels were measured on day 1 following surgery, and each lobe of the liver was weighed on day 14. Serum VEGF levels in non-hepatectomized, tumor-bearing mice exceeded those in their non-tumor-bearing counterparts; however, the administration of bevacizumab did not reduce the serum VEGF levels. The volume of the liver lobe of the hepatectomized, CT26-transplanted and non-CT26-transplanted mice was 1,349.6 and 735.5 mg, respectively, indicating rapid growth of the CT26 transplant (p=0.023). The volume of the CT26-transplanted lobe of the bevacizumab-administered mice was 1,379.0 mg, which was not significantly different from that (1,349.6 mg) of the non-bevacizumab-administered mice. The volume of the remnant lobe of the bevacizumab-administered mice was 1,051.0 mg, which did not significantly differ from that (957.3 mg) of the non-bevacizumab-administered mice. The administration of bevacizumab following hepatectomy did not delay remnant liver regeneration, and did not suppress the growth of metastases in the remnant lobes or remnant liver regeneration.