Proliferative activity of intrahepatic colorectal metastases after preoperative hemihepatic portal vein embolization

Although hemihepatic portal vein embolization (PVE) has been used preoperat ively to extend indications for hepatectomy in patients with colorectal met astases, the effects of this procedure on tumor growth and outcome remain c ontroversial. To address this issue, we assessed the proliferative activity of intrahepatic metastases after PVE and the long-term outcome of this pro cedure. Eighteen patients with colorectal metastases underwent preoperative PVE between 1996 and 2000 (PVE group). Twenty-nine patients who underwent major hepatic resection without PVE served as control (non-PVE group). The hepatic parenchymal fraction of the left lobe had significantly increased f rom 38.1 +/- 3.2% to 45.9 +/- 2.9% 3 weeks after PVE (+20.5%, P < .0001). T umor volume and percent tumor volume had also significantly increased from 223 +/- 89 mL to 270 +/- 97 mL (+20.8%, P = .016) and from 13.7 +/- 4.3% to 16.2 +/- 4.9% (+18.5%, P = .014), respectively. There was no apparent corr elation between the increase in parenchymal volume and that in tumor volume . The Ki-67 labeling index of metastatic lesions was 46.6 +/- 7.2% in the P VE group and 35.4 +/- 12.6% in the non-PVE group (P = .013). Long-term surv ival was similar in the PVE and non-PVE groups, however, disease-free survi val was significantly poorer in the PVE group than in the non-PVE group (P = .004). We conclude that PVE increases tumor growth and probably is associ ated with enhanced recurrence of disease. Although PVE is effective in exte nding indications for surgery, patient selection for PVE should be cautious .