Myung-Wook Kim

Multidimensional learning curve in laparoscopy-assisted gastrectomy for early gastric cancer

BackgroundLaparoscopy-assisted gastrectomy (LAG) is a complex and time-consuming procedure, which is increasingly used for early gastric cancer (EGC). We provide a multidimensional analysis of the learning curve in LAG.MethodsCumulative sum method was used to analyze outcomes of 109 patients undergoing LAG for EGC by one surgeon over a two year period; the influence of patient selection was evaluated. Target failure rate was set at 10%, with failure defined as open conversion, mortality, major morbidity, residual tumor, or inappropriate lymphadenectomy.ResultsThere were 19 failures-fourteen performance and five oncologic. The learning curve, which displayed a slight rising trend and three phases was achieved after 40 cases with selected patients; it was broken, however, by the introduction of advanced procedures and unselected patients.ConclusionsAdvanced procedures and broad indications in LAG should be delayed until a learning curve is completed under the target failure rate.

Conditional loss of TGF-beta signalling leads to increased susceptibility to gastrointestinal carcinogenesis in mice.

Downregulation of TGF‐β receptors is implicated in colon cancer development. Inactivation of either of the two transmembrane serine/threonine kinases, TGF‐β1 types I/II receptors, is now implicated in carcinogenesis, especially gastrointestinal carcinogenesis.

Significant Correlation between Serum Level of Hepatocyte Growth Factor and Progression of Gastric Carcinoma

Abstract. Hepatocyte growth factor (HGF) can promote proliferation of many types of tumor cells including gastric cancer cells. To study the role of HGF in the progression of gastric carcinoma, HGF levels were measured by an enzyme immunoassay (EIA) system in sera of gastric cancer patients and followed up the levels after the operation. The mean serum HGF level in 212 healthy control subjects, 140 patients with primary gastric cancer, and 13 patients with recurrent gastric cancer were 0.199 ± 0.073, 0.325 ± 0.209, and 0.578 ± 0.258 ng/ml, respectively. The increase of the levels was significantly correlated with the progression of tumor stage. The levels decreased to normal levels 1 month after curative resection of the tumors. However, the levels did not decrease significantly in nonresected cases. During the follow-up of the patients for several months, the level was significantly increased in recurrent gastric cancer patients, whereas there was no increase in nonrecurrent patients. In conclusion, the serum HGF levels significantly correlated with the aggressiveness of the tumors, suggesting an important role of HGF in the progression of gastric carcinoma.

Helicobacter pylori infection promotes gastric carcinogenesis in a mice model

Debate that Helicobacter pylori might play a causative role in gastric carcinogenesis still exists in spite of the World Health Organization’s definition of H. pylori as a class I carcinogen. In order to define the exact role of H. pylori infection in gastric carcinogenesis, we established a mice model of H. pylori infection.

Hepatic resection for hepatocellular carcinoma meeting Milan criteria in Child-Turcotte-Pugh class a patients with cirrhosis.

This study evaluated whether hepatic resection is a reasonable strategy as an initial treatment for hepatocellular carcinoma (HCC) meeting Milan criteria in patients with compensated cirrhosis. From the database of 435 consecutive patients with resection of HCC between July 1994 and May 2007, 213 patients were found to have Child-Turcotte-Pugh class A cirrhosis and HCC meeting Milan criteria, as shown by preoperative image studies. We examined long-term survivals and patterns of recurrence after hepatic resection among those patients. Overall survival rates at 1, 3, 5, and 10 years were 92%, 78%, 69%, and 52%, respectively, and 1-, 3-, 5-, and 10-year disease-free survival rates were 79%, 57%, 44%, and 19%, respectively. Pathological review indicated that 36/213 patients (16.9%) had another nodule and/or gross vascular invasion. Microvascular invasion, tumor size, and histological grade of cirrhosis were independent risk factors for recurrence. Sixty percent of recurrent cases met the Milan criteria. The six patients who underwent living donor salvage liver transplantation (OLT) for intrahepatic recurrence were alive without recurrence at a median of 24 (range = 8-31) months. These favorable data suggest that hepatic resection is a good option for small HCCs in patients with compensated cirrhosis; and salvage OLT may be reserved for patients with recurrences.

Salvage Liver Transplantation for Recurrent Hepatocellular Carcinoma After Liver Resection: Feasibility of the Milan Criteria and Operative Risk

INTRODUCTION Although the Milan criteria are widely accepted for liver transplantation (OLT) for hepatocellular carcinoma (HCC), they have not been fully evaluated as feasible for salvage liver transplantation (SLT) of recurrent HCC after hepatic resection. The operative difficulties of SLT increase the operative risk. The aim of this study was to evaluate the feasibility of the Milan criteria for SLT and its operative complications. PATIENTS AND METHODS From March 2005 to November 2007, 46 HCC patients received OLT including 15 SLTs after prior partial hepatectomy (SLT group) and 31 primary OLTs (PLT group). RESULTS There was no postsurgical hospital mortality among the SLT group but one case in the PLT group due to pneumonia followed by sepsis. There was no difference in the incidence of surgical complications between the two groups. Overall survival rates of SLT group patients were similar to those of the PLT group (P = .14), especially comparing both groups of patients within the Milan criteria (P = .89). There was no recurrence of HCC among the patients within the Milan criteria. CONCLUSIONS SLT is a feasible procedure for recurrent HCC meeting the Milan criteria; the operative risk of the SLT is also acceptable.

Long-term evaluation of mice model infected with Helicobacter pylori: focus on gastric pathology including gastric cancer.

Background : Long‐term evaluation of gastric pathology after H. pylori infection is very important in order to reveal its clinical implications, since debate still exists on the gastric carcinogenesis provoked by H. pylori infection in animal models.

Duct-to-Duct Biliary Reconstructions and Complications in 100 Living Donor Liver Transplantations

OBJECTIVE We evaluated the risk factors for biliary complications and surgical procedures for duct-to-duct reconstructions in adult living donor liver transplantation (LDLT). PATIENTS AND METHODS From February 2005 to March 2008, we performed 100 cases of adult LDLT with duct-to-duct biliary reconstruction, using 64 right lobe grafts, 33 left lobe grafts, and 3 right lateral grafts. We employed 4 types of duct-to-duct procedures: all interrupted 6-0 Prolene suture (group 1, n = 9); continuous posterior and interrupted anterior wall 6-0 Prolene suture (group 2, n = 49); all continuous 7-0 Prolene suture (group 3, n = 26); and all continuous 7-0 Prolene suture with external stent (group 4, n = 16). Biliary complications were defined as an anastomosis stricture or a leakage. RESULTS Thirty-four patients experienced biliary complications during the follow-up period (median, 27 months). The incidence of stricture was 27% and that of leakage, 8%. There were no perioperative, intraoperative, or anatomic risk factors for biliary complications, except the type of duct-to-duct procedure. Group 1 and 2 patients showed higher incidences of biliary strictures than groups 3 and 4 (43.1% vs 4.7%; P = .00). Group 3 patients experienced a higher incidence of bile leakage than the other groups (23.1% vs 2.7%; P = .004). CONCLUSIONS The type of biliary reconstruction is a factor affecting biliary complications following duct-to-duct anastomosis in LDLT. Duct-to-duct biliary anastomosis with 7-0 monofilament suture and a small external stent is a feasible procedure in LDLT that significantly reduces the incidence of biliary complications.

Volumetry-based selection of right posterior sector grafts for adult living donor liver transplantation.

To determine the feasibility of volumetric criteria without anatomic exclusion for the selection of right posterior sector (RPS) grafts for adult‐to‐adult living donor liver transplantation (LDLT), we reviewed and compared our transplant data for RPS grafts and right lobe (RL) grafts. Between January 2008 and September 2010, adult‐to‐adult LDLT was performed 65 times at our institute; 13 of the procedures (20%) were performed with RPS grafts [the posterior sector (PS) group], and 39 (60%) were performed with RL grafts (the RL group). The volumetry of the 13 RPS donor livers showed that the RPS volume was 39.8% ± 7.6% of the total liver volume. Ten of the 13 donors had to donate RPS grafts because the left liver volume was inadequate. All donor procedures were performed successfully, and all donors recovered from hepatectomy. However, longer operative times were required for the procurement of RPS grafts versus RL grafts (418 ± 40 versus 345 ± 48 minutes, P < 0.001). The postoperative recovery of liver function was smoother for the donors of the PS group versus the donors of the RL group. The RPS grafts had significantly smaller hepatic artery and bile duct openings than the RL grafts. All recipients with RPS grafts survived LDLT. No recipients experienced vascular graft complications or small‐for‐size graft dysfunction. There were no significant differences in the incidence of posttransplant complications between the donors and recipients of the PS and RL groups. The 3‐year graft survival rates were favorable in both groups (100% in the PS group versus 91% in the RL group). In conclusion, the selection of RPS grafts by volume criteria is a feasible strategy for an adult‐to‐adult LDLT program. Liver Transpl 17:1046–1058, 2011.

Effects and problems of adult ABO-incompatible living donor liver transplantation using protocol of plasma exchange, intra-arterial infusion therapy, and anti-CD20 monoclonal antibody without splenectomy: case reports of initial experiences and results in Korea.

INTRODUCTION Adult ABO-incompatible liver transplantation is associated with a high risk of graft failure due to antibody-mediated humoral rejection (AMR). We evaluated the effects of a protocol using preoperative removal of isohemagglutinin, rituximab prophylaxis, and intrahepatic arterial infusion (HAI) therapy for ABO-incompatible adult living donor liver transplantation (LDLT). PATIENTS AND METHODS Between March 2005 and September 2007, we performed 94 adult LDLTs, including 3 ABO-incompatible cases. All ABO-incompatible LDLT patients underwent administration of 375 mg/m(2) rituximab on preoperative days 15 and 8 without splenectomy, as well as preoperative removal of isohemagglutinin using plasma exchange, and HAI therapy for postoperative 21 days. RESULTS Postoperative anti-donor blood-type antibody titer and B-cell level were effectively suppressed by early rituximab prophylaxis in all patients. HAI therapy was effective to prevent AMR and even resolved mild AMR. However, all patients suffered bacterial infections, and 1 died of septicemia with good graft function. Another subject died of late-onset AMR that occurred after discontinuation of HAI therapy. CONCLUSION An ABO-incompatible LDLT protocol using plasma exchange, rituximab prophylaxis, and intra-HAI therapy effectively suppressed anti-A/B antibody and prevented AMR. But this protocol should be further improved to reduce infectious complications and late onset of AMR.