Surgical outcome and risk scoring to predict survival after hepatic resection for hepatocellular carcinoma with portal vein tumor thrombosis.

Backgrounds/Aims: The hepatocellular carcinoma (HCC) with portal vein tumor thrombosis (PVTT) is classified as the advanced stage (BCLC stage C) with extremely poor prognosis, and in current guidelines is recommended for systemic therapy. This study aimed to evaluate the surgical outcomes and long-term prognosis after hepatic resection (HR) for patients who have HCC combined with PVTT. Methods: We retrospectively analyzed 332 patients who underwent HR for HCC with PVTT at ten tertiary referral hospitals in South Korea. Results: The median overall and recurrence-free survival after HR were 32.4 and 8.6 months, while the 1-, 3-, and 5-year overall survival rates were 75%, 48%, and 39%, respectively. In multivariate analysis, tumor number, tumor size, AFP, PIVKA-II, neutrophil-to-lymphocyte ratio, and albumin-bilirubin (ALBI) grade were significant prognostic factors. The risk scoring was developed using these seven factors-tumor, inflammation and hepatic function (TIF), to predict patient prognosis. The prognosis of the patients was well stratified according to the scores (log-rank test, p < 0.001). Conclusions: HR for patients who have HCC combined with PVTT provided favorable survival outcomes. The risk scoring was useful in predicting prognosis, and determining the appropriate treatment strategy for those patients who have HCC with PVTT.

Clinical outcome of surgical resection for multifocal T2-T3 hepatocellular carcinoma up to 3 nodules: a comparative analysis with a single nodule.

BACKGROUND/AIMS: Although the Barcelona Clinic Liver Cancer staging system seems to underestimate the impact of curative-intent surgical resection for multifocal hepatocellular carcinoma (HCC), recent studies have indicated favorable results for the surgical resection of multiple HCC. This study aimed to assess clinical outcomes and feasibility of surgical resection for multifocal HCC with up to three nodules compared with single tumor cases. METHODS: Patients who underwent surgical resection for HCC with up to three nodules between 2009 and 2020 were included, and those with the American Joint Committee on Cancer (AJCC) 8th edition, T1 and T4 stages were excluded to reduce differences in disease distribution and severity. Finally, 81 and 52 patients were included in the single and multiple treatment groups, respectively. Short- and long-term outcomes including recurrence-free survival (RFS) and overall survival (OS), were evaluated. RESULTS: All patients were classified as Child-Pugh class A. RFS and OS were not significantly different between the two groups (P=0.176 and P=0.966, respectively). Multivariate analysis revealed that transfusion and intrahepatic metastasis were significantly associated with recurrence (P=0.046 and P=0.005, respectively). Additionally, intrahepatic metastasis was significantly associated with OS (hazard ratio, 1.989; 95% confidence interval, 1.040-3.802; P=0.038). CONCLUSIONS: Since there was no significant difference in survival between the single and multiple groups among patients with AJCC 8th stage T2 and T3, surgical resection with curative intent could be considered with acceptable long-term survival for selected patients with multiple HCC of up to three nodules.

A single-center experience of over 300 cases of single-incision robotic cholecystectomy comparing the da Vinci SP with the Si/Xi systems.

Minimally invasive surgery is usually more beneficial than open surgeries in various fields of surgery. With the newly developed Single-Port (SP) robotic surgical system, even single-site surgery has become easier to access. We compared single-incision robotic cholecystectomy between the Si/Xi and SP systems. This retrospective single-center study enrolled patients who underwent single-incision robotic cholecystectomy between July 2014 and July 2021. The clinical outcomes of the da Vinci Si/Xi and SP systems were compared. In total, 334 patients underwent single-incision robotic cholecystectomy (118 Si/Xi vs. 216 SP). The SP group had more chronic or acute cholecystitis than the Si/Xi group did. There was more bile spillage in the Si/Xi group during the surgery. The total operative and docking times were significantly shorter in the SP group. There was no difference in the postoperative outcomes. The SP system is safe and feasible regarding comparable postoperative complication rates and is more convenient regarding docking and techniques.

Should we be reluctant to perform pancreatectomy in patients with chronic liver disease? A single center 10-year experience.

PURPOSE: Many studies have shown extra-hepatic surgery in patients with chronic liver disease (CLD) with or without portal hypertension can result in complications. The aim of this study was to analyze the results of major pancreatectomy in patients with CLD including cirrhosis and to evaluate their efficacy and safety. METHODS: We retrospectively reviewed 319 patients undergoing open pancreatoduodenectomy (PD) or distal pancreatectomy (DP) in our center. Those who received PD and DP in patients without CLD were classified into groups A and D, and those with CLD into groups B and C, respectively. Group B and C were subdivided into groups 1 and 2 according to the presence of portal hypertension. RESULTS: Forty-three patients (13.5%) had CLD. Of the 221 patients who received PD, 25 had CLD. Of the 98 patients who received DP, 18 (Group C) had CLD. In the PD group, patients with portal hypertension (group B1) had longer operative time. However, the transfusion rate and complication rate were not significantly different from other groups. There was no mortality in patients with CLD without portal hypertension (group B2) and the complication and mortality rate was comparable to patients with normal liver function (group A). In the DP group, the transfusion rate, complication rate and mortality rate were significantly higher in patients with portal hypertension (group C1). CONCLUSIONS: Acceptable outcomes were obtainable following pancreatic surgery in cirrhotic, non-portal hypertensive patients with surgical outcomes equivalent to non-cirrhotic patients.AbbreviationsCLDchronic liver diseasePDpancreaticoduodenectomyDPdistal pancreatectomy.

Left liver graft in adult-to-adult living donor liver transplantation with an optimal portal flow modulation strategy to overcome the small-for-size syndrome - A retrospective cohort study.

BACKGROUND: Adult-to-adult living donor liver transplantation (LDLT) is a notable type of liver transplantation. Several centers prefer the right liver graft (RLG) over the left liver graft (LLG) for better recovery of recipients. We compared the outcomes of donors and recipients between LDLT using LLGs and RLGs. MATERIALS AND METHODS: The study cohort comprised of 25 patients in the LLG group and 93 in the RLG group. When both hemiliver grafts met the selection criteria, an LLG was preferred. When portal flow (≥300 ml/min/100gLW) and hepatic venous pressure gradient (≥10 mmHg) were increased, intraoperative splenic artery ligation was performed for portal modulation. Postoperatively, somatostatin was administered when small-for-size syndrome (SFSS) was highly suspected. RESULTS: The graft-to-recipient weight ratio was lower in the LLG group than in the RLG group. There was no significant complication above Clavien-Dindo grade IIIA in donors. Regarding recipient outcomes, SFSS occurred in four (16.0%) patients in the LLG group and three (3.2%) in the RLG group (P = 0.036). Splenic artery ligation was frequently performed in the LLG group than the RLG group (5 [20.0%] vs. 12 [12.9%], P = 0.035) and 5 patients received intravenous continuous somatostatin for 7 (5-12) days. SFSS-related hospital mortality did not occur. There was no significant difference in the short-term and long-term outcomes between the groups. CONCLUSION: This study demonstrates the comparable outcomes of donors and recipients between the LLG and RLG groups although with a higher risk of SFSS that needs high experience to avoid severe complications and graft loss. We expect LLG to be used more actively in adult-to-adult LDLT with portal flow modulation strategies to overcome fatal SFSS.

Prevalence and clinical significance of pancreatic cystic lesions in immunosuppressed patients following solid organ transplantation.

Background: Pancreatic cystic lesions (PCLs) are occasionally found in solid organ transplant (SOT) recipients. In such recipients, the risk of cancer is increased due to immunosuppressive therapy. This study investigated the prevalence of PCLs and described their clinical course in immunosuppressed patients following SOT. Methods: The presence of PCLs in a retrospective cohort of 805 consecutive SOT recipients from 2009 to 2019 was examined. The characteristics of PCLs were compared using initial and follow-up imaging, where available. These results were compared to an age- and sex-matched immunocompetent control group monitored for at least 12 months. Results: PCLs were present in 15 of 805 SOT patients (seven liver and eight kidney transplantations). The median diameter of the largest lesion was 20 mm (range, 0.2-60 mm) and 60% of lesions were benign. During follow-up imaging, the cyst size remained stable in 46.7%, increased in 13.3%, and decreased in 40.0% of the SOT group. Significantly more of the SOT patients showed PCL size reductions (P=0.007). Among SOT patients diagnosed with intraductal papillary mucinous neoplasms (6/15), worrisome features were noted in one patient at the time of cyst diagnosis. Differences in the development of worrisome features between the study and control groups were not statistically significant. Conclusions: The malignant transformation of PCLs in SOT recipients is rare and most such PCLs can be managed conservatively. The presence of a PCL should therefore not affect transplant eligibility.

Right posterior bile duct stricture after central bisectionectomy or anterior sectionectomy.

PURPOSE: Before performing anterior sectionectomy (AS) or central bisectionectomy (CBS), the anatomy of the right posterior bile duct (RPBD) must be cautiously assessed owing to the many variations of the RPBD and its variations could be related to bile duct injury. METHODS: Clinical data of patients who underwent AS or CBS from 2009 to 2018 were reviewed. The bile duct anatomy according to Okubo's criteria and the right bile duct (RBD) length were evaluated using MRI, and we performed a risk factor analysis of the RPBD stricture (RPBDS). RESULTS: A total of 68 patients were included. Type A bile ducts were the most common (n = 36, 52.9%). Five (7.2%) patients had RPBDS requiring intervention. RPBDS only occurred in patients with a type A bile duct and a type A portal vein undergoing surgery using the Glissonian sheath approach. Moreover, when the RBD length was > 12 mm, the sensitivity and specificity were 0.8 and 0.889, respectively. In multivariate analysis, RBD length of > 12 mm was significant. CONCLUSION: A careful review of RPBD anatomy especially in patient with long RBD and caution when using the anterior Glissonian sheath approach might be helpful to prevent RPBDS during AS or CBS.

Single-port robot plus one port (SP + 1) distal pancreatectomy using the new da Vinci SP system.

PURPOSE: Single-incision laparoscopic distal pancreatectomy has not been widely applied due to technical challenges and increased operative risks. The newly released da Vinci SP system has been introduced to overcome these limitations and offer improvements for established robotic single-site procedures. We report our experience of robotic single port plus one port distal pancreatectomy using the da Vinci SP system. METHODS: We performed robotic distal pancreatectomy in three patients using the da Vinci SP surgical system with one additional port used for applying the energy device and stapling. Technical and clinical feasibility were examined. RESULTS: The mean age and body mass index were 70.7 years and 27.8 kg/m2, respectively. The mean operation time was 215 min. The estimated blood loss was less than 500 mL. All patients underwent combined splenectomy. The postoperative course of all patients was uneventful. CONCLUSION: Robotic distal pancreatectomy using the da Vinci SP system is safe and feasible, with acceptable perioperative outcomes.

Efficacy and Safety of Hepatitis B Virus Vaccination Following Hepatitis B Immunoglobulin Withdrawal After Liver Transplantation.

BACKGROUND: Hepatitis B immunoglobulin (HBIG) and oral nucleoside/nucleotide analogs have been the mainstay of hepatitis B virus (HBV) prophylaxis after liver transplantation. However, long-term HBIG administration could have disadvantages, such as an increase in medical costs and the development of mutant HBV strains. This study aimed to investigate the safety and efficacy of HBV vaccination after the withdrawal of HBIG after liver transplantation. METHODS: This prospective open-label single-arm observational clinical trial enrolled 41 patients who underwent liver transplantation between 2010 and 2016 because of a condition related to chronic HBV infection. At the time of enrollment, all patients had taken entecavir and discontinued HBIG administration. When hepatitis B surface antibody titer was undetectable after the withdrawal of HBIG, a recombinant HBV vaccine was injected intramuscularly at month 0, 1, and 6. RESULTS: After excluding 5 patients who dropped out and 2 patients who had a persistent hepatitis B surface antibody titer, 9 (26.5%) of 34 patients had a positive vaccination response. The median hepatitis B surface antibody titer at seroconversion was 86 (12-1000) IU/L, and those at the end of follow-up were 216 (30-1000) IU/L. No patients experienced HBV recurrence during the study period. Sex (female, odds ratio 32.91 [1.83-592.54], P = .018) and the dosing interval of HBIG before withdrawal (≥90 days, 16.21 [1.21-217.31], P = .035) were independent contributing factors for positive response to the vaccination. CONCLUSION: HBV vaccination still deserves consideration as active immunoprophylaxis after liver transplantation because it could provide added immunity to nucleoside/nucleotide analogs monotherapy with excellent cost-effectiveness.

Portal modulation effects of terlipressin on liver regeneration and survival in a porcine model subjected to 90% hepatectomy.

BACKGROUND: Excessive postoperative portal pressure is associated with post-hepatectomy liver failure and small-for-size syndrome after partial liver transplantation. This study aimed to identify the portal modulation effects of terlipressin on liver regeneration and survival in a porcine model subjected to 90% hepatectomy. METHODS: Twenty pigs undergoing 90% hepatectomy were divided into control (n = 10) and terlipressin (n = 10) groups. Terlipressin 0.5 mg was injected subcutaneously three times a day, from immediately before hepatectomy to 7 days after surgery, for surviving pigs in the terlipressin group. Portal pressure measurement, biochemical analysis, assessment of molecular markers for liver regeneration, and immunohistochemistry were performed in both groups. RESULTS: The 7-day survival rate was significantly higher in the terlipressin group than that in the control group. Portal pressure in the terlipressin group was lower than that in the control group at 30 min and 1 h after hepatectomy. Total bilirubin level was lower in the terlipressin group than that in the control group at 1 h and 6 h after hepatectomy. Proliferating cell nuclear antigen expression was higher in the control group than that in the terlipressin group at 6 h after hepatectomy, while the proportion of Ki-67-positive cells was higher in the terlipressin group than that in the control group at 7 days after hepatectomy. Endothelin-1 level reflecting liver injury was lower in the terlipressin group than that in the control group at 1 h and 6 h after hepatectomy. CONCLUSION: Terlipressin could optimize liver regeneration and improve survival through rapid and effective portal modulation after extensive hepatectomy.

The beneficial impacts of splanchnic vasoactive agents on hepatic functional recovery in massive hepatectomy porcine model.

BACKGROUND: Excessive portal pressure after massive hepatectomy can cause hepatic sinusoidal injury and have deleterious impacts on hepatic functional recovery, contributing to developing post-hepatectomy liver failure. This study aimed to assess the effects of splanchnic vasoactive agents on hepatic functional recovery and regeneration while clarifying the underlying mechanism, using a 70% hepatectomy porcine model. METHODS: Eighteen pigs undergoing 70% hepatectomy were involved in this study and divided into three groups: control (n=6), terlipressin (n=6), and octreotide (n=6). Terlipressin (0.5 mg) and octreotide (0.2 mg) were administered 3 times a day for each group with the first dose starting just before surgery until the 7th postoperative day, at which time the surviving pigs were sacrificed. During the period, portal pressure, liver weight, biochemical analysis, histological injury score, and molecular markers were evaluated and compared between groups. RESULTS: The 7-day survival rates in the octreotide, terlipressin, and control groups were 100%, 83.3%, and 66.7%, respectively. The portal pressures decreased in both terlipressin and octreotide groups than the control group at 30 minutes, 1 hour and 6 hours after hepatectomy. The amount of regeneration measured by liver weight to body weight ratio at the time of sacrifice in the terlipressin group was smaller than that in the control group (117% vs. 129%, P=0.03). Serum aspartate aminotransferase (AST) and total bilirubin levels at 1 and 6 hours after hepatectomy and prothrombin time/international normalized ratio (PT/INR) at 6 hours after hepatectomy were significantly improved in the terlipressin and octreotide groups compared to the control group. Serum endothelin-1 (ET-1) was significantly lower in the terlipressin group than that in the control group 6 hours after hepatectomy (P<0.01). The histological injury score in the control group was significantly higher than that in the terlipressin group on the 7th postoperative day (P<0.01). CONCLUSIONS: Splanchnic vasoactive agents, such as terlipressin and octreotide, could effectively decrease portal pressure and attenuate liver injury after massive hepatectomy.

Lipidomic signatures of post-hepatectomy liver failure using porcine hepatectomy models.

BACKGROUND: Clinical diagnosis of post-hepatectomy liver failure (PHLF) can only be made on or after the 5th postoperative day. Biomarker for early diagnosis is considered as a critical unmet need. METHODS: Twenty domestic female crossbreed (Yorkshire-landrace and duroc) pigs underwent sham operation (n=6), 70% (n=7) and 90% (n=7) partial hepatectomy (PH). A comprehensive lipidomic analysis was conducted using sera collected at pre-operation (PO), 14, 30, and 48 h after PH using nanoflow ultrahigh performance liquid chromatography-electrospray ionization-tandem mass spectrometry. RESULTS: Of the 184 quantified lipids, 14 lipids showed significant differences between the two resection groups starting at 30 h after surgery. Four phosphatidylcholine (PC) plasmalogen species (P-16:0/16:0, P-18:0/18:2, P-18:0/20:4, and P-18:0/22:6) and PC 32:2 significantly increased in the 90% PH group while these returned to PO level after 30 h in the 70% PH group, presumably implying the failure markers. In contrast, eight triacylglycerol (TG) species (40:0, 42:1, 42:0, 44:1, 44:2, 46:1, 46:2, and 48:3) and sphingomyelin d18:1/20:0 showed an opposite trend, wherein they significantly decreased in the 90% PH group while these in the 70% PH group were abruptly increased until 30 h but returned to near PO levels at 48 h, implying the recovery markers. Same trends could also be observed in the level of whole lipid classes of PC plasmalogens and TGs, in addition to selected individual lipid species. CONCLUSIONS: Characteristic lipidomic signatures of PHLF could be identified using large animal models. These candidates have a potential to serve as a tool for early diagnosis and may open new paths to the study to overcome PHLF.

Feasibility and safety of bisegmentectomy 7-8 while preserving hepatic venous outflow of the right liver - A retrospective cohort study.

BACKGROUND: When a hepatic tumor is deeply located in segments 7 and 8 around the right hepatic vein (RHV), right hemihepatectomy (RH) could be excessive owing to the resection of large tumor-free segments. This study aimed to evaluate the feasibility and safety of bisegmentectomy 7-8 (S7-8) and to compare its surgical outcomes with those of RH. MATERIALS AND METHODS: Consecutive patients who underwent S7-8 and RH were enrolled in this study. In the S7-8 group, 14 patients with an obvious inferior right hepatic vein (IRHV) (median: 6 mm; range: 3.6-8.8 mm) underwent S7-8 without hepatic vein reconstruction. RHV reconstruction was performed in six patients without an IRHV, involving direct anastomosis of the RHV in five patients and reconstruction using a cryo-preserved iliac vein in one patient. RESULTS: A total of 61 patients were included (20 in S7-8 group; 41 in RH group). No significant differences were observed other than higher a model of end-stage liver disease score in the RH group than in the S7-8 group (7 [6-20] vs. 6 [6-9], P = 0.003). Post-hepatectomy liver failure including severe grades was more frequent in the RH group (43.9% vs. 10%, P = 0.008). In the S7-8 group, two patients with direct RHV reconstruction had RHV anastomosis obstruction, and eventually required insertion of a metallic stent. However, computed tomography performed 4 weeks after the operation showed intact venous outflow of the right liver in the S7-8 group. CONCLUSION: S7-8 can be performed safely in selected patients with a thick IRHV. For patients with no obvious IRHV, RHV reconstruction could be a good surgical strategy to retain venous outflow of the right liver with feasible outcomes.

Explorative study of serum biomarkers of liver failure after liver resection.

Conventional biochemical markers have limited usefulness in the prediction of early liver dysfunction. We, therefore, tried to find more useful liver failure biomarkers after liver resection that are highly sensitive to internal and external challenges in the biological system with a focus on liver metabolites. Twenty pigs were divided into the following 3 groups: sham operation group (n = 6), 70% hepatectomy group (n = 7) as a safety margin of resection model, and 90% hepatectomy group (n = 7) as a liver failure model. Blood sampling was performed preoperatively and at 1, 6, 14, 30, 38, and 48 hours after surgery, and 129 primary metabolites were profiled. Orthogonal projection to latent structures-discriminant analysis revealed that, unlike in the 70% hepatectomy and sham operation groups, central carbon metabolism was the most significant factor in the 90% hepatectomy group. Binary logistic regression analysis was used to develop a predictive model for mortality risk following hepatectomy. The recommended variables were malic acid, methionine, tryptophan, glucose, and γ-aminobutyric acid. Area under the curve of the linear combination of five metabolites was 0.993 (95% confidence interval: 0.927-1.000, sensitivity: 100.0, specificity: 94.87). We proposed robust biomarker panels that can accurately predict mortality risk associated with hepatectomy.

Right-side versus left-side hepatectomy for the treatment of hilar cholangiocarcinoma: a comparative study.

BACKGROUND: Radical resection is the only curative treatment for patients with hilar cholangiocarcinoma. While left-side hepatectomy (LH) may have an oncological disadvantage over right-side hepatectomy (RH) owing to the contiguous anatomical relationship between right hepatic inflow and biliary confluence, a small future liver remnant after RH could cause worse surgical morbidity and mortality. We retrospectively compared surgical morbidity and long-term outcome between RH and LH to determine the optimal surgical strategy for the treatment of hilar cholangiocarcinoma. METHODS: This study considered 83 patients who underwent surgical resection for hilar cholangiocarcinoma between 2010 and 2017. Among them, 57 patients undergoing curative-intent surgery including liver resection were enrolled for analysis-33 in the RH group and 27 in the LH group. Prospectively collected clinicopathologic characteristics, perioperative outcomes, and long-term survival were evaluated. RESULTS: Portal vein embolization was more frequently performed in the RH group than in the LH group (18.2% vs. 0%, P = 0.034). The proportion of R0 resection was comparable in both groups (75.8% vs. 75.0%, P = 0.948). The 5-year overall and recurrence-free survival rates did not differ between the groups (37.7% vs. 41.9%, P = 0.500, and 26.3% vs. 33.9%, P = 0.580, respectively). The side of liver resection did not affect long-term survival. In multivariate analysis, transfusion (odds ratio, 3.12 [1.42-6.87], P = 0.005) and post-hepatectomy liver failure (≥ grade B, 4.62 [1.86-11.49], P = 0.001) were independent risk factors for overall survival. CONCLUSIONS: We recommend deciding the side of liver resection according to the possibility of achieving radical resection considering the anatomical differences between RH and LH.

Analysis of risk factors for portal vein thrombosis after liver resection.

PURPOSE: We evaluated the risk factors for posthepatectomy thrombosis including portal vein thrombosis (PVT) and clinical outcomes. METHODS: We retrospectively analyzed 563 patients who had undergone hepatectomy from February 2009 to December 2014. Twenty-nine patients with preoperatively confirmed thrombosis and tumor recurrence-related thrombosis were excluded. We identified the location of the thrombosis as main portal vein (MPV), peripheral portal vein (PPV) and other site such as hepatic vein or inferior vena cava. Patients with MPV thrombosis and PPV thrombosis with main portal flow disturbance were treated with anticoagulation therapy. We performed operative thrombectomy before anticoagulation therapy who did combined portal vein (PV) segmental resection. RESULTS: Of the 534 patients, 22 (4.1%) developed posthepatectomy thrombosis after hepatectomy. Among them, 19 (86.4%) had PVT. The mean duration of Pringle's maneuver was significant longer in the PVT group than the no-thrombosis group (P = 0.020). Patients who underwent combined PV segmental resection during hepatectomy were more likely to develop posthepatectomy PVT (P = 0.001). Thirteen patients who had MPV thrombosis and PPV thrombosis with main portal flow disturbance received anticoagulation therapy immediately after diagnosis and all of them were improved. Among them, 2 patients who developed PVT at the PV anastomosis site after PV segmental resection, underwent operative thrombectomy before anticoagulation therapy and both were improved. There were no patients who developed complications related to anticoagulation therapy. CONCLUSION: Long duration of Pringle's maneuver and PV segmental resection were risk factors. Anticoagulation therapy or operative thrombectomy should be considered for PVT without contraindications.

Prevalence and Clinical Significance of Biliary Intraepithelial Neoplasia (BilIN) in Cholangiocarcinoma.

Biliary intraepithelial neoplasia (BilIN) is the most common noninvasive precursor lesion which progresses to cholangiocarcinoma (CC) and is often found synchronously adjacent to the tumor or at the surgical resection margin. The aim of this study was to elucidate the prevalence and prognostic effect of BilIN on survival after resection for CC. We retrospectively analyzed the database of patients with CC who underwent surgery performed at our institution from 2010 to 2017. There were 142 patients who underwent surgery for CC. BilIN was detected in 42 patients (29.5%). On univariate analysis, extrahepatic CC (ExtraH CC) patients with BilIN lesions significantly showed better disease-free survival (P = 0.05). Also, although not statistically significant, ExtraH CC patients with BilIN lesions revealed better overall survival (OS) (P = 0.09). On multivariate analysis, presence of BilIN lesion, irrespective of location, was significantly associated with better disease-free survival (HR = 2.059, 95% confidence interval (CI): 1.057-4.432, P = 0.041) and OS (HR = 1.831, 95% CI: 1.149-3.534, P = 0.044) in ExtraH CC patients. The presence of BilIN lesions was not uncommon in CC patients and was significantly associated with better disease-free survival and OS in ExtraH CC patients. However, larger studies with longer follow-up are needed to accurately determine its clinical significance.

Clinical significance of post-hepatectomy hepatic failure in patients with liver metastases from colorectal cancer.

BACKGROUNDS/AIMS: This study attempted to identify risk factors for development of post-hepatectomy hepatic failure (PHF) and its effect on long-term survival of patients with liver metastases from colorectal cancer. METHODS: We carried out a retrospective study of 143 patients who had been diagnosed with liver metastases from colorectal cancer and who had undergone hepatectomy between 2003 and 2010. We allocated these patients to PHF and non-PHF groups, using the definition of the International Study Group of Liver Surgery, and compared the clinical factors of the two groups, using Cox regression and Kaplan-Meier analysis to evaluate the differences in overall survival (OS) and recurrence-free survival (RFS) between these groups. RESULTS: The PHF group comprised 19 patients (13.3%); all had Grade A PHF. Independent risk factors for development of PHF were metachronous liver metastases and major hepatectomy. The differences between the PHF and non-PHF groups in OS or RFS were not statistically significant; however, the PHF group tended to have a worse prognosis. Multivariate analysis revealed significant associations between OS and the factors of poor differentiation of the primary colorectal cancer, major hepatectomy, and positive resection margin. CONCLUSIONS: Major hepatectomy is an important risk factor for PHF in patients with liver metastases from colorectal cancer. The pathological characteristics of the primary tumor are more important as predictors than is Grade A PHF.

Occupational stress and related factors among surgical residents in Korea.

PURPOSE: The application rate for surgical residents in Korea has continuously decreased over the past few years. The demanding workload and the occupational stress of surgical training are likely causes of this problem. The aim of this study was to investigate occupational stress and its related factors in Korean surgical residents. METHODS: With the support of the Korean Surgical Society, we conducted an electronic survey of Korean surgical residents related to occupational stress. We used the Korean Occupational Stress Scale (KOSS) to measure occupational stress. We analyzed the data focused on the stress level and the factors associated with occupational stress. RESULTS: The mean KOSS score of the surgical residents was 55.39, which was significantly higher than that of practicing surgeons (48.16, P < 0.001) and the average score of specialized professionals (46.03, P < 0.001). Exercise was the only factor found to be significantly associated with KOSS score (P = 0.001) in univariate analysis. However, in multiple linear regression analysis, the mean number of assigned patients, resident occupation rate and exercise were all significantly associated with KOSS score. CONCLUSION: Surgical residents have high occupational stress compared to practicing surgeons and other professionals. Their mean number of assigned patients, resident recruitment rate and exercise were all significantly associated with occupational stress for surgical residents.