Kenneth Sh Chok

High-intensity focused ultrasound ablation: An effective bridging therapy for hepatocellular carcinoma patients

AIM To analyze whether high-intensity focused ultrasound (HIFU) ablation is an effective bridging therapy for patients with hepatocellular carcinoma (HCC). METHODS From January 2007 to December 2010, 49 consecutive HCC patients were listed for liver transplantation (UCSF criteria). The median waiting time for transplantation was 9.5 mo. Twenty-nine patients received transarterial chemoembolization (TACE) as a bringing therapy and 16 patients received no treatment before transplantation. Five patients received HIFU ablation as a bridging therapy. Another five patients with the same tumor staging (within the UCSF criteria) who received HIFU ablation but not on the transplant list were included for comparison. Patients were comparable in terms of Child-Pugh and model for end-stage liver disease scores, tumor size and number, and cause of cirrhosis. RESULTS The HIFU group and TACE group showed no difference in terms of tumor size and tumor number. One patient in the HIFU group and no patient in the TACE group had gross ascites. The median hospital stay was 1 d (range, 1-21 d) in the TACE group and two days (range, 1-9 d) in the HIFU group (P < 0.000). No HIFU-related complication occurred. In the HIFU group, nine patients (90%) had complete response and one patient (10%) had partial response to the treatment. In the TACE group, only one patient (3%) had response to the treatment while 14 patients (48%) had stable disease and 14 patients (48%) had progressive disease (P = 0.00). Seven patients in the TACE group and no patient in the HIFU group dropped out from the transplant waiting list (P = 0.559). CONCLUSION HIFU ablation is safe and effective in the treatment of HCC for patients with advanced cirrhosis. It may reduce the drop-out rate of liver transplant candidate.

Modulation of graft vascular inflow guided by flowmetry and manometry in liver transplantation

BACKGROUND Survival of the partial graft after living donor liver transplantation owes much to its tremendous regenerative ability. With excellent venous outflow capacity, a graft within a wide range of graft-to-standard-liver-volume ratios can cope with portal hypertension that is common in liver transplant recipients. However, when the ratio range is exceeded, modulation of graft vascular inflow becomes necessary for graft survival. The interplay between graft-to-standard-liver-volume ratio and portal pressure, in the presence of portosystemic shunt or otherwise, requires individualized modulation of graft portal and arterial inflows. Boosting of portal inflow by shunt ligation can be guided by transonic flowmetry, whereas muting of portal inflow by splenic artery ligation can be monitored by portal electronic manometry. METHOD We describe four cases to illustrate the above. RESULTS One patient had hepatic artery thrombosis resulting from splenic artery steal syndrome which was the sequela of small-for-size syndrome. Emergency splenic artery ligation and re-anastomosis of the hepatic artery successfully muted the portal inflow and boosted the hepatic arterial inflow. Another patient with portal vein thrombosis underwent thrombendvenectomy. Portal inflow was boosted with ligation of portosystemic shunt, which is often present in these patients with portal hypertension. The coexistence of splenic aneurysm and splenorenal shunt required ligation of both in the third patient. The fourth patient, with portal pressure and flow monitoring, avoided ligation of a coronary vein which became a main portal inflow after portal thrombendvenectomy. CONCLUSION Management of graft inflow modulation guided selectively by transonic flowmetry or portal manometry was described.

Rapid measurement of indocyanine green retention by pulse spectrophotometry: A validation study in 70 patients with Child-Pugh A cirrhosis before hepatectomy for hepatocellular carcinoma

BACKGROUND The indocyanine green (ICG) retention test is the most popular liver function test for selecting patients for major hepatectomy. Traditionally, it is done using spectrophotometry with serial blood sampling. The newly-developed pulse spectrophotometry is a faster alternative, but its accuracy on Child-Pugh A cirrhotic patients undergoing hepatectomy for hepatocellular carcinoma has not been well documented. This study aimed to assess the accuracy of the LiMON(®), one of the pulse spectrophotometry systems, in measuring preoperative ICG retention in these patients and to devise an easy formula for conversion of the results so that they can be compared with classical literature records where ICG retention was measured by the traditional method. METHODS We measured the liver function of 70 Child-Pugh A cirrhotic patients before hepatectomy for hepatocellular carcinoma from September 2008 to January 2009. ICG retention at 15 minutes measured by traditional spectrophotometry (ICGR15) was compared with ICG retention at 15 minutes measured by the LiMON (ICGR15(L)). RESULTS The median ICGR15 was 14.7% (5.6%-32%) and the median ICGR15(L) was 10.4% (1.2%-28%). The mean difference between them was -4.3606. There was a strong correlation between ICGR15 and ICGR15(L) (correlation coefficient, 0.844; 95% confidence interval, 0.762-0.899). The following formula was devised: ICGR15=1.16XICGR15(L)+2.73. CONCLUSIONS The LiMON provides a fast and repeatable way to measure ICG retention at 15 minutes, but with constant underestimation of the real value. Therefore, when comparing results obtained by traditional spectrophotometry and the LiMON, adjustment of results from the latter is necessary, and this can be done with a simple mathematical calculation using the above formula.

Survival outcomes of right-lobe living donor liver transplantation for patients with high Model for End-stage Liver Disease scores.

BACKGROUND Controversy exists over whether living donor liver transplantation (LDLT) should be offered to patients with high Model for End-stage Liver Disease (MELD) scores. This study tried to determine whether a high MELD score would result in inferior outcomes of right-lobe LDLT. METHODS Among 411 consecutive patients who received right-lobe LDLT at our center, 143 were included in this study. The patients were divided into two groups according to their MELD scores: a high-score group (MELD score ≥25; n=75) and a low-score group (MELD score <25; n=68). Their demographic data and perioperative conditions were compared. Univariable and multivariable analyses were performed to identify risk factors affecting patient survival. RESULTS In the high-score group, more patients required preoperative intensive care unit admission (49.3% vs 2.9%; P<0.001), mechanical ventilation (21.3% vs 0%; P<0.001), or hemodialysis (13.3% vs 0%; P=0.005); the waiting time before LDLT was shorter (4 vs 66 days; P<0.001); more blood was transfused during operation (7 vs 2 units; P<0.001); patients stayed longer in the intensive care unit (6 vs 3 days; P<0.001) and hospital (21 vs 15 days; P=0.015) after transplantation; more patients developed early postoperative complications (69.3% vs 50.0%; P=0.018); and values of postoperative peak blood parameters were higher. However, the two groups had comparable hospital mortality. Graft survival and patient overall survival at one year (94.7% vs 95.6%; 95.9% vs 96.9%), three years (91.9% vs 92.6%; 93.2% vs 95.3%), and five years (90.2% vs 90.2%; 93.2% vs 95.3%) were also similar between the groups. CONCLUSIONS Although the high-score group had significantly more early postoperative complications, the two groups had comparable hospital mortality and similar satisfactory rates of graft survival and patient overall survival. Therefore, a high MELD score should not be a contraindication to right-lobe LDLT if donor risk and recipient benefit are taken into full account.

Pancreaticoduodenectomy with vascular reconstruction for adenocarcinoma of the pancreas with borderline resectability.

AIM To analyze whether pancreaticoduodenectomy with simultaneous resection of tumor-involved vessels is a safe approach with acceptable patient survival. METHODS Between January 2001 and March 2012, 136 patients received pancreaticoduodenectomy for adenocarcinoma at our hospital. Seventy-eight patients diagnosed with pancreatic head carcinoma were included in this study. Among them, 46 patients received standard pancreaticoduodenectomy (group 1) and 32 patients received pancreaticoduodenectomy with simultaneous resection of the portal vein or the superior mesenteric vein or artery (group 2) followed by reconstruction. The immediate surgical outcomes and survivals were compared between the groups. Fifty-five patients with unresectable adenocarcinoma of the pancreas without liver metastasis who received only bypass operations (group 3) were selected for additional survival comparison. RESULTS The median ages of patients were 67 years (range: 37-82 years) in group 1, and 63 years (range: 35-86 years) in group 2. All group 2 patients had resection of the portal vein or the superior mesenteric vein and three patients had resection of the superior mesenteric artery. The pancreatic fistula formation rate was 21.7% (10/46) in group 1 and 15.6% (5/32) in group 2 (P = 0.662). Two hospital deaths (4.3%) occurred in group 1 and one hospital death (3.1%) occurred in group 2 (P = 0.641). The one-year, three-year and five-year overall survival rates in group 1 were 71.1%, 23.6% and 13.5%, respectively. The corresponding rates in group 2 were 70.6%, 33.3% and 22.2% (P = 0.815). The one-year survival rate in group 3 was 13.8%. Pancreaticoduodenectomy with simultaneous vascular resection was safe for pancreatic head adenocarcinoma. CONCLUSION The short-term and survival outcomes with simultaneous resection were not compromised when compared with that of standard pancreaticoduodenectomy.

Acute pancreatitis induced by transarterial chemoembolization: a single-center experience of over 1500 cases

BACKGROUND Acute pancreatitis is a relatively rare but potentially lethal complication after transarterial chemotherapy. This study aimed to review the complications such as acute pancreatitis after transarterial chemotherapy with or without embolization for hepatocellular carcinoma. METHODS A total of 1632 patients with hepatocellular carcinoma who had undergone transarterial chemoembolization from January 2000 to February 2014 in a single-center were reviewed retrospectively. We investigated the potential complications of transarterial chemoembolization, such as acute pancreatitis and acute pancreatitis-related complications. RESULTS Of the 1632 patients with hepatocellular carcinoma who had undergone 5434 transarterial chemoembolizations, 1328 were male and 304 female. The median age of these patients was 61 years. Most (79.6%) of the patients suffered from HBV-related hepatocellular carcinoma. The median tumor size was 5.2 cm. Of the 1632 patients, 145 patients underwent transarterial chemoembolization with doxorubicin eluting bead, making up a total of 538 episodes. The remaining patients underwent transarterial chemoembolization with cisplatin. Seven (0.4%) patients suffered from acute pancreatitis post-chemoembolization. Six patients had chemoembolization with doxorubicin and one had chemoembolization with cisplatin. Patients who received doxorubicin eluting bead had a higher risk of acute pancreatitis [6/145 (4.1%) vs 1/1487 (0.1%), P<0.0001]. Two patients had anatomical arterial variations. Four patients developed acute pancreatitis-related complications including necrotizing pancreatitis (n=3) and pseudocyst formation (n=1). All of the 4 patients resolved after the use of antibiotics and other conservative treatment. Three patients had further transarterial chemoembolization without any complication. CONCLUSIONS Acute pancreatitis after transarterial chemoembolization could result in serious complications, especially after treatment with doxorubicin eluting bead. Continuation of current treatment with transarterial chemoembolization after acute pancreatitis is feasible providing the initial attack is completely resolved.

Radiological prognosticators of hepatocellular carcinoma treated by hepatectomy.

BACKGROUND Hepatectomy is the main curative treatment for hepatocellular carcinoma (HCC), but postoperative long-term survival is poor. Preoperative radiological features of HCC displayed by computed tomography or magnetic resonance imaging could serve as additional prognostic factors. This study aimed to identify preoperative radiological features of HCC that may be of prognostic significance in hepatectomy. METHODS Ninety-two patients who underwent hepatectomy for HCC were included in this study. Preoperative radiological features including tumor number, size, location (peripheral, middle, central), portal vein invasion, hepatic vein invasion, and presence of pseudo-capsule were analyzed in relation to survival. RESULTS With a median follow-up period of 41.7 months, the 1-, 3- and 5-year overall survival rates were 85%, 65% and 58%, respectively. Univariate analysis showed that portal vein invasion and absence of pseudo-capsule were significant prognostic factors for overall survival, while all the examined radiological features were prognostic factors for disease-free survival. Multivariate analysis for overall survival found no significant factor. On multivariate analysis for disease-free survival, patients who had tumors with portal vein invasion had poorer survival with a hazard ratio of 2.26 (95% CI, 1.05-4.91; P=0.038) and patients with single nodular HCC or pseudo-capsulated HCC had better survival with a hazard ratio of 0.50 (95% CI, 0.27-0.94; P=0.032) and 0.38 (95% CI, 0.14-0.99; P=0.048), respectively. CONCLUSIONS Demonstrable pseudo-capsule of HCC and solitary HCC on imaging and absence of portal vein invasion are features associated with better disease-free survival after hepatectomy. These features may guide treatment planning for HCC.

High-Intensity Focused Ultrasound Ablation as a Bridging Therapy for Hepatocellular Carcinoma Patients Awaiting Liver Transplantation

The scarcity of liver grafts in Asia leads to a significant dropout of patients from liver transplant waiting lists, particularly patients with hepatocellular carcinoma and a low model for end-stage liver disease score. In order to reduce dropping out, different bridging therapies are employed. We report the use of high-intensity focused ultrasound ablation as a bridging therapy for a patient with hepatocellular carcinoma of stage two and an extremely low platelet count (20X109/L). The ablation was successful. Blood tests showed that his liver function was similar before and after the treatment. No adhesion was encountered in the liver transplantation performed six months later.

Outcomes of side-to-side conversion hepaticojejunostomy for biliary anastomotic stricture after right-liver living donor liver transplantation

BACKGROUND Conversion hepaticojejunostomy is considered the salvage intervention for biliary anastomotic stricture, a common complication of right-liver living donor liver transplantation with duct-to-duct anastomosis, after failed endoscopic treatment. The aim of this study is to compare the outcomes of side-to-side hepaticojejunostomy with those of end-to-side hepaticojejunostomy. METHODS Prospectively collected data of 402 adult patients who had undergone right-liver living donor liver transplantation with duct-to-duct anastomosis were reviewed. Diagnosis of biliary anastomotic stricture was made based on clinical, biochemical, histological and radiological results. Endoscopic treatment was the first-line treatment of biliary anastomotic stricture. RESULTS Interventional radiological or endoscopic treatment failed to correct the biliary anastomotic stricture in 13 patients, so they underwent conversion hepaticojejunostomy. Ten of them received end-to-side hepaticojejunostomy and three received side-to-side hepaticojejunostomy. In the end-to-side group, two patients sustained hepatic artery injury requiring repeated microvascular anastomosis, two developed re-stenosis requiring further percutaneous transhepatic biliary drainage and balloon dilatation, and two required revision hepaticojejunostomy. In the side-to-side group, one patient developed re-stenosis requiring further endoscopic retrograde cholangiography and balloon dilatation. No re-operation was needed in this group. Otherwise, outcomes in the two groups were similar in terms of liver function and graft survival. CONCLUSIONS Despite the similar outcomes, side-to-side hepaticojejunostomy may be a better option for bile duct reconstruction after failed interventional radiological or endoscopic treatment because it can decrease the chance of hepatic artery injury and allows future endoscopic treatment if re-stricture develops. However, more large-scale studies are warranted to validate the results.

Emergency re-routing of anterior sector venous outflow for right lobe living donor liver transplantation including the middle hepatic vein

BACKGROUND Controversy remains over whether the middle hepatic vein should be included in the liver graft in right liver living donor liver transplantation. Congestion in the anterior sector of a right liver graft can cause graft malfunction, which is especially devastating in the case of a graft with marginal size in relation to recipient body size on top of poor pre-transplant recipient status. The case we report here highlighted the importance of the middle hepatic vein in right liver living donor liver transplantation. METHODS We illustrated the rectification of outflow obstruction of the middle hepatic vein in the anterior sector of right liver graft caused by technical error during transplantation. The rectification was performed with emergency re-routing using an artificial conduit. RESULT Congestion in the anterior sector of the graft improved immediately and the patients postoperative liver function test results improved gradually. CONCLUSIONS The middle hepatic vein is important for effective drainage of the anterior sector of a right liver graft. The re-routing technique described in the report can also be applied to cases in which the middle hepatic vein is injured during hepatectomy requiring immediate reconstruction.