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Breakthroughs in Liver Surgery




Patients with liver diseases now benefit from a wide range of treatment options including microwave ablation, transarterial embolization, portal vein embolization, staged hepatic resection, and neoadjuvant chemotherapy.

For patients with extensive tumor burden in the liver, mostly caused by metastatic colon cancers and metastatic endocrine tumors, a combination of resection and ablation may be recommended. This involves treating part of the liver tumor using either Y-90, transarterial embolization or portal vein embolization with metal coils to deliver ablative or radiation doses to the target tissue. After this procedure, the embolized segment of the liver is surgically removed. To treat both sides of the liver, or if the tumors are large, surgery can be done in a staged fashion. In this setting, patients would get one lobe of their liver treated in an initial surgery, and then return about three weeks later to have the remainder of the tumor in the other lobe resected.

Portal vein embolization takes advantage of the liver’s unique ability to regenerate. Mechanically obstructing a branch of the portal vein causes the opposite lobe of the liver to hypertrophy. Often in patients with bile duct cancers, the right hepatic lobe and the middle part of the left lobe of the liver need to be removed. After embolization of the right portal vein, the left lobe will become two to three times larger. Approximately four weeks after the venous blood supply to the right lobe of the liver is obstructed by embolization, the patient is reimaged to determine the extent of hypertrophy of the left lobe of the liver. Once the remaining segment of the left lobe of the liver remodels, the surgeons can safely remove the portion of the left lobe involved with tumor along with the entire right lobe of the liver. This will leave the patient with about 40% of viable liver tissue, a more than acceptable amount to sustain life.

Another innovative procedure is portal vein embolization for patients whose tumor is localized in the middle of the liver. The location of the tumor in these patients often poses a challenge because complete tumor resection would require removal of so much tissue that the remaining liver volume would be too little to support life. The minimum liver volume needed for a patient to survive is about 25% to 30% of the liver. Surgically removing a tumor from the middle of the liver would require resection of about 80% of the liver. However, by combining portal vein embolization with staged hepatic resection, an increased number of patients can be treated surgically for bile duct cancers and other metastatic tumors that are centrally located within the liver.

For patients with primary liver cancers and metastatic colon cancer, complete surgical resection with curative intent is usually the best treatment option. Many patients, however, will present with tumors that are too large for surgical removal. One option is to offer combined treatment whereby these patients first undergo three months of chemotherapy. Patients would then be re-evaluated with imaging to assess tumor response. If the tumor response was favorable, complete surgical resection could be offered.

Through this type of coordinated and integrated multidisciplinary approach, many patients originally deemed surgically unresectable would become candidates for surgical intervention. Surgical referral for evaluation at the initial presentation should be considered for those patients with extensive liver involvement of primary or metastatic carcinomas. Because of innovative therapies, many patients who were not previously eligible for surgical treatments can now benefit from them.

Dr. Christopher Siegel is Chief, Division of Hepatobiliary Surgery, and Surgical Director, Liver Center of Excellence, University Hospitals (UH) Digestive Health Institute at UH Case Medical Center. He is also Associate Professor of Surgery, 
Case Western Reserve University School 
of Medicine.

Source: MD News Jan. 2013, Cleveland/Akron/Canton Edition


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