Extending the indications for curative liver resection by portal vein embolization

Improved liver function after portal vein embolization and an elective right hepatectomy

BACKGROUND

Portal vein embolization (PVE) is used before extensive hepatic resections to increase the volume of the future remnant liver within acceptable safety margins (conventionally >0.6% of the patient's weight). The objective was to determine whether pre-operative PVE impacts on post-operative liver function independently from the increase in liver volume.

METHODS

The post-operative liver function of patients who underwent an anatomical right liver resection with (n = 28) and without (n = 53) PVE were retrospectively analysed. Donors of the right liver were also analysed (LD) (n = 17).

RESULTS

Patient characteristics were similar, except for age, weight and American Society of Anesthesiologists (ASA) score that were lower in LD. Post-operative factor V and bilirubin levels were, respectively, higher and lower in patients with PVE compared with patients without PVE or LD (P < 0.05). Patients with PVE had an increased blood loss, blood transfusions and sinusoidal obstruction syndrome. The day-3 bilirubin level was 40% lower in the PVE group compared with the no-PVE group after adjustment for body weight, chemotherapy, operating time, Pringle time, blood transfusions, remnant liver volume, pre-operative bilirubin level and pre-operative prothrombin ratio (P = 0.001).

CONCLUSIONS

For equivalent volumes, the immediate post-operative hepatic function appears to be better in livers prepared with PVE than in unprepared livers. Future studies should analyse whether the conventional inferior volume limit that allows a safe liver resection may be lowered when a PVE is performed.

Radiofrequency ablation resulting in left lobe hypertrophy and improved resectability

Surgical resection for colorectal liver metastases may only be considered when an adequate functional residual volume can be preserved. Selective portal venous embolisation may be used to increase this volume, whilst chemotherapy and radiofrequency ablation (RFA) can be used to treat inoperable lesions. A 73-year-old man with liver metastasis proceeded to surgery, with the intention to perform a right hemi-hepatectomy. Unexpectedly at laparotomy, despite adequate pre-operative imaging, both the right and middle hepatic veins were involved. At that time extended right hemi-hepatectomy was contraindicated by insufficient residual volume and RFA was performed. Follow-up imaging revealed atrophy of the lesion. Significantly, there was also left lateral lobe hypertrophy sufficient to permit resection, which was performed without complication. Thrombosis of intra-hepatic portal veins is a recognised complication of RFA but here it appears to have been beneficial. The case highlights the need for regular review of unresectable hepatic disease by a liver surgeon and could suggest new modalities of portal embolisation.

Liver resection for colorectal liver metastasis

At some point in the natural course of colorectal cancer up to 50% of patients will develop metastasis to the liver. Historically only 20% of these patients would have to be deemed resectable, with an intent to cure, at the time of presentation. But with recent improvements in cross-sectional imaging, chemotherapeutic agents and advances in the techniques of surgical resection the emphasis of resection has now changed to 'who is not resectable' as opposed to 'who is resectable'. There are few contraindications to liver resection on the proviso that the patient is fit enough. As a result of this paradigm shift, 5 year survival rates are approaching 60%. Historically liver resection was perceived as a formidable operation but now liver resection for CRLM is safe and specialist centres are reporting mortality rates of less than 1%. This review briefly covers the standard techniques currently employed and some of the recent innovations being developed to improve resectability.

Electrolysis and other local ablative treatments for non-resectable colorectal liver metastases

The present paper is a review of the current ablative treatment options for the treatment of colorectal liver metastases. Cryotherapy, microwave coagulation therapy, radiofrequency ablation and laser-induced thermotherapy are discussed. Electrolysis, a novel non-thermal ablative treatment, is described. Potential benefits of electrolysis include the apparent ability to safely and effectively treat lesions abutting major hepatic structures and the lack of a systemic inflammatory reaction following electrolytic ablation. Further studies in animals and humans are needed to confirm this potential and to further refine the methods of electrolytic treatment of colorectal liver metastases.