Gallstone ileus inducing obstructive jaundice at the afferent loop of Roux-en-Y hepaticojejunostomy after bile duct cancer surgery: a case report

The diagnosis of gallstone ileus is occasionally challenging due to the variability of its presentation. We herein present a very rare case of gallstone ileus inducing obstructive jaundice at the afferent loop of Roux-en-Y hepaticojejunostomy after 10 years of bile duct cancer surgery. We describe the case of a 74-year-old Korean woman with obstructive jaundice, treated conservatively. She showed severely impaired liver function test and obstructive jaundice. The computed tomography (CT) scan led to a diagnosis of very rare type of gallstones ileus at the afferent jejunal loop. Since the clinical manifestation was improved, we decided to observe her closely. On the next follow-up CT scan, the gallstone disappeared with mild distension of the afferent bowel loop, implicating spontaneous passage of the gallstone. She recovered and returned to normal life after 10 days of initiation of clinical manifestations. We presume that the gallstone may enter the afferent jejunal loop through the hepaticojejunostomy and later increase in size. The presence of narrow tract of intestine may facilitate the incidence of gallstone ileus. It appears to be the first report on this rare type of gallstone ileus inducing obstructive jaundice.

Balloon dilation of jejunal afferent loop functional stenosis following left hepatectomy and hepaticojejunostomy long time after pylorus-preserving pancreaticoduodenectomy: a case report

We present a rare case of functional stenosis of the jejunal loop following left hepatectomy and hepaticojejunostomy long after pylorus-preserving pancreaticoduodenectomy (PPPD), which was successfully managed by balloon dilation. A 70-year-old Korean man had undergone PPPD 6 years before due to 1.8 cm-sized distal bile duct cancer. Sudden onset of obstructive jaundice led to diagnosis of recurrent bile duct cancer mimicking perihilar cholangiocarcinoma of type IIIb. After left portal vein embolization, the patient underwent resection of the left liver and caudate lobe and remnant extrahepatic bile duct. The pre-existing jejunal loop and choledochojejunostomy site were used again for new hepaticojejunostomy. The patient recovered uneventfully, but clamping of the percutaneous transhepatic biliary drainage (PTBD) tube resulted in cholangitis. Biliary imaging studies revealed that biliary passage into the afferent jejunal limb was significantly impaired. We performed balloon dilation of the afferent jejunal loop by using a 20 mm-wide balloon. Follow-up hepatobiliary scintigraphy showed gradual improvement in biliary excretion and the PTBD tube was removed at 1 month after balloon dilation. This very unusual condition was regarded as disuse atrophy of the jejunal loop, which was successfully managed by balloon dilation and intraluminal keeping of a large-bore PTBD tube for 1 month.

Prognostic effect of preoperative sequential transcatheter arterial chemoembolization and portal vein embolization for right hepatectomy in patients with solitary hepatocellular carcinoma

Backgrounds/Aims

Both preoperative transcatheter arterial chemoembolization (TACE) alone and portal vein embolization (PVE) alone have a detrimental prognostic effect on the post-resection outcomes in patients with hepatocellular carcinoma (HCC). The main objective of this study was to assess the prognostic impact of preoperative TACE on the long-term survival outcomes in patients undergoing preoperative PVE and right liver resection for solitary HCC.

Methods

Patients who underwent macroscopic curative right liver resection of solitary HCC that lied between 3.0 and 7.0 cm (n=113) with or without preoperative TACE and PVE were selected for the study, making these subjects were divided into three groups; the TACE-PVE group (n=27), the PVE-alone group (n=13), and the control group (n=73). The subjects in the three groups were followed up for ≥36 months or until death.

Results

The 1-, 3-, 5-, and 10-year overall patient survival rates of all 113 patients were 96.5%, 88.2%, 81.3% and 65.0%, respectively. The 1-, 3-, 5-, and 10-year overall patient survival rates were 96.3%, 83.4%, 83.4% and 47.6% respectively in the TACE-PVE group; 84.6%, 76.9%, 57.7% and 19.2% respectively in the PVE-alone group; and 98.6%, 91.7%, 85.1% and 81.7% respectively in the control group (p=0.047). Patients were also sub-grouped according to tumor size, and those with a tumor of up to cutoff at 5 cm showed no prognostic difference (p=0.774), but tumor size >5 cm was associated with inferior patient survival only in the TACE-PVE group (p=0.018).

Conclusions

Preoperative sequential TACE and PVE appear to be compliant to the conventional oncological concept in addition to induction of the future remnant liver regeneration. Therefore, we suggest that preoperative TACE should be come first whenever preoperative PVE for major hepatectomy is planned, especially in patients with hypervascular HCC tumors.

Safety and usefulness of warm dissection technique during liver graft retrieval from deceased donors

BACKGROUND

For deceased-donor liver graft retrieval, the warm dissection technique of hilar dissection before perfusion had been the standard procedure in the early period of liver transplantation. Thereafter, the cold dissection technique of in situ flushing and hilar dissection after perfusion has been preferred in many transplantation centers for rapid procurement of multiple organs. This study intended to assess the safety and usefulness of the warm dissection technique used in deceased-donor liver transplantation.

METHODS

This study analyzed a single surgeon's experience of the warm dissection technique for 165 cases of liver graft retrieval, regarding the prolongation of retrieval operation time, retrieval-associated graft injury, and recipient outcomes.

RESULTS

An additional 20 to 40 minutes was required for warm dissection. The incidence of retrieval-associated graft injury was 13 (7.9%), in which hepatic parenchymal injury was detected in 7 (capsular tear in 6 and subcapsular hematoma in 1) and vascular injury in 6 (celiac axis injury in 5 and common hepatic artery injury in 1). There was no other episode of injury at the branch artery, vena cava, portal vein, and bile duct. There was no significant difference of 1-year graft survival rates between liver grafts with and without graft injury (83% vs 83.3%, P = .73).

CONCLUSIONS

When the vital signs of deceased donor are stable, the warm dissection technique may be helpful to decrease the cold ischemic preservation time because the risk of graft injury is acceptably low and it provides more time for recipient preparation, thus giving potential advantages for marginal liver grafts.

Synergistic effect of sorafenib and vitamin K on suppression of hepatocellular carcinoma cell migration and metastasis

Vitamin K plays a role in controlling cell growth. Anti-angiogenic effects of sorafenib lead to impairment of vitamin K uptake and induction of des-γ-carboxyprothrombin release by hepatocellular carcinoma (HCC) cells. We examined sorafenib and vitamin K individually and in combination regarding their ability to suppress migration and metastatic potential of HCC cells. HepG2 cells (HCC cell line) were treated with hepatocyte growth factor (HGF). E-Cadherin expression, phospho-MET (p-MET), and phospho-extracellular signal-regulated kinase (p-ERK) levels and cell migration were evaluated. HGF-stimulated HepG2 cells, which were treated with a combination of sorafenib and vitamin K, showed significantly increased expression of E-cadherin and impairment of migration ability compared to when treated with either agent alone. This combination therapy also induced marked inhibition of epithelial-mesenchymal transition phenotype; inhibition of HGF-stimulated cell proliferation, invasion and migration; and inhibition of HGF/c-MET signaling pathway. Levels of p-MET and p-ERK were also significantly reduced by this combination. Our experimental study demonstrated that sorafenib and vitamin K can function synergistically to inhibit the migration and proliferation of HCC cells. Combination therapy with sorafenib and vitamin K appears to be worthy of clinical trial with expectation of synergistic therapeutic effects.

Sorafenib inhibits migration and invasion of hepatocellular carcinoma cells through suppression of matrix metalloproteinase expression

Sorafenib increases survival of patients with advanced hepatocellular carcinoma (HCC) by inhibiting RAF kinase and receptor tyrosine kinase activity, but involvement of sorafenib in fibrosis and epithelial-mesenchymal transition (EMT) remains unclear. To elucidate effects of sorafenib on EMT progression and matrix metalloproteinase (MMP) activity, levels of E-cadherin, N-cadherin, and MMPs were evaluated in HepG2 human HCC cells induced by hepatocyte growth factor (HGF). Scratching cell migration assay, matrigel cell invasion assay, and immuno histochemistry were performed to examine effects of sorafenib on tumor metastasis and MMP expression. Sorafenib inhibited HGF-induced EMT and suppressed cell migration and invasion. Treatment with sorafenib significantly reduced HGF-enhanced expression of MMPs, suggesting that inhibition of MMP activity contributes to suppression of cellular motility and invasiveness of HepG2 cells. Neutralization of MMP activity by antibodies to MMP2/9, broad-spectrum MMP inhibitor or selective gelatinase inhibitor resulted in significant suppression of HGF-induced EMT and cell migration/invasion. Sorafenib treatment and MMP inactivation inhibited HGF-induced c-MET and MEK/ERK pathways. Sorafenib reduced MMP activity in this HGF-induced tumorigenic model of HCC. These findings provide in vitro evidence that sorafenib suppresses HGF-induced EMT and cell migration/invasion, as well as HGF-induced c-MET and MEK/ERK pathways.

Fatal scedosporiosis in multiple solid organ allografts transmitted from a nearly-drowned donor

Scedosporium spp. is the most common mold infection in pneumonia resulting from near-drowning. Three fatal scedosporiosis cases developed after solid organ transplantation, probably transmitted from the nearly-drowned donor. One heart transplant recipient and two kidney transplant recipients developed fatal scedosporiosis following deceased donor transplantation from the same donor, a nearly-drowned victim of a suicide attempt. Genotypically, indistinguishable strains of Scedosporium auratiacum were recovered from the three recipients. Two liver transplant recipients from the same donor received prophylactic voriconazole without any subsequent signs of infection. To determine the safety of donation from nearly-drowned donors, a national traceback investigation was also performed of the causes of deaths in all transplant recipients who received organs from drowned donors between 2001 and 2013. Over 13 years, 2600 deceased donor transplants were performed in Korea. Among these 2600 deceased donor transplants, 27 (1%) victims of drowning donated their organs. From these 27 donors, 84 patients received organ transplants and 18 died, including the above three. We found no microbiologic evidence of invasive mold transmission from the nearly-drowned donors to the other 15 recipients. Although disseminated infection in the donor could not be demonstrated by culture, undiagnosed disseminated donor infection and transmission of Scedosporium spp. should be considered in near-drowning events.

Liver transplantation for metabolic liver disease: experience at a living donor dominant liver transplantation center

PURPOSE

Metabolic liver disease (MLD) often progresses to life-threatening conditions. This study intends to describe the outcomes of liver transplantation (LTx) for MLD at a living donor-dominant transplantation center where potentially heterozygous carrier grafts are employed.

METHODS

We retrospectively evaluated the medical records of 54 patients with MLD who underwent LTx between November 1995 and February 2012 at Asan Medical Center in Seoul, Korea. The cumulative graft and patient survival rates were analyzed according to patient age, and living or deceased donor LTx. Recurrence of the original disease was also investigated.

RESULTS

The post-transplant cumulative patient survival rates at one, five, and 10 years were 90.7%, 87.5% and 87.5%, and the graft survival rates were 88.8%, 85.5%, and 85.5%, respectively. There were no differences in the patient survival rates according to the recipient age, human leukocyte antigen matching, and living or deceased donor LTx. There were also no differences in the patient survival rates between the MLD and the non-MLD groups for children. Recurrence of the original metabolic disease was not observed in any patient during the follow-up period.

CONCLUSION

Our results suggest that the living donor-dominant transplantation program is well-tolerated in MLD without recurrence of the original MLD using all types of transplantation.

Customized left-sided hepatectomy and bile duct resection for perihilar cholangiocarcinoma in a patient with left-sided gallbladder and multiple combined anomalies

Left-sided gallbladder (LSGB) is a rare anomaly, but it is often associated with multiple combined variations of the liver anatomy. We present the case of a patient with LSGB who underwent successful resection of perihilar cholangiocarcinoma. The patient was a 67-year-old male who presented with upper abdominal pain and obstructive jaundice. Initial imaging studies led to the diagnosis of Bismuth-Corlette type IIIB perihilar cholangiocarcinoma. Due to the unique location of the gallbladder and combined multiple hepatic anomalies, LSGB was highly suspected. During surgery after hilar dissection, we recognized that the tumor was located at the imaginary hilar bile duct bifurcation, but its actual location was corresponding to the biliary confluence of the left median and lateral sections. The extent of resection included extended left lateral sectionectomy, caudate lobe resection, and bile duct resection. Since some of the umbilical portion of the portal vein was invaded, it was resected and repaired with a portal vein branch patch. Due to anatomical variation of the biliary system, only one right-sided duct was reconstructed. The patient recovered uneventfully without any complication. LSGB should be recognized as a constellation of multiple hepatic anomalies, and therefore, thorough investigations are necessary to enable the performance of safe hepatic and biliary resections.

Survival analysis following resection of AJCC stage III gallbladder carcinoma based on different combinations of T and N stages

Backgrounds/Aims

According to 7th AJCC TNM staging system, gallbladder carcinoma (GBC) with lymph node (LN) metastasis is classified as N1 or N2; thus making the stage IIIB (N1) or IVB (N2). Stage IIIB consists of N1 status with wide coverage of T1-3, but T3N1 group often showed poorer outcomes than T1-2N1 groups. This study intended to assess post-resection prognosis of T3N1 versus other stage III subgroups.

Methods

We selected 103 patients from our institutional database of GBC who underwent R0 resection between July 1996 and June 2009 and whose GBC was confined to stage T3N0, T1-3N1 or T1-3N2. These patients were stratified into five groups, namely, T3N0 (n=26), T1N1 (n=13), T2N1 (n=35), T3N1 (n=20) and T1-3N2 (n=9), and were followed for ≥5 years or until death.

Results

Surgical procedures were minor liver resection (n=53), minor liver resection with bile duct resection (n=23), major liver resection (n=12), major liver resection with bile duct resection (n=5), and hepatopancreatoduodenectomy (n=12). Mean follow-up period was 57.2±68.5 months. Overall 5-year survival rate based on all-cause death and cancer-associated death, respectively, was 57.7% and 60.6% in T3N0, 15.4% and 15.4% in T1N1 (n=13), 28.6% and 28.6% in T2N1 (n=35), 5.0% and 5.7% in T3N1 (n=20), and 22.2% and 22.2% in T1-3N2. The survival outcome of T3N1 group was the poorest among the four stage III groups and was comparable to that of stage IVB (p=0.53).

Conclusions

The prognosis of T3N1 GBC is unusually poor even after R0 resection, thus we suggest extensive LN dissection may be necessary in patients with T3 tumors for accurate prognostic evaluation and radical removal of potential nodal micrometastasis. Further validation of this result is necessary in large patient populations from multiple centers.

An interim safety analysis of hepatocellular carcinoma patients administrating oral vitamin K with or without sorafenib

Backgrounds/Aims

Vitamin K may plays a role in controlling hepatocellular carcinoma (HCC) cell growth. In this study, we intended to present 5-year experience of 72 patients receiving oral vitamin K with or without sorafenib. Its end-point was to evaluate the safety of combination therapy using sorafenib and vitamin K.

Methods

An interim analysis was performed as a single-arm cross-sectional study, including 72 HCC patients who underwent liver resection or transplantation and administered oral vitamin K2 alone (n=47) or with sorafenib (n=25).

Results

In all patients, administration of vitamin K2 analog 45 mg/day did not show any noticeable adverse side-effect during vitamin K therapy of 23.3±10.6 months, except for one patient who experienced skin rash at the third day of vitamin K therapy. In 25 patients receiving sorafenib and vitamin K for 6 months or longer, any noticeable adverse side-effect suspected of vitamin K origin was not identified yet. A small proportion of patients showed unexpectedly favorable anti-tumor effects after use of vitamin K with or without sorafenib.

Conclusions

Because add-on of oral vitamin K did not increase the adverse side-effects of sorafenib, a combination therapy with these two agents appears to be worthy of further clinical trial with an expectation of synergistic therapeutic effects.

Pneumatosis intestinalis after adult living donor liver transplantation: report of three cases and collective literature review

BACKGROUNDS/AIMS

Pneumatosis intestinalis (PI) is a condition in which multiple gas-filled mural cysts develop in the gastrointestinal tract. Although its exact etiology remains obscure, PI is rarely observed in liver transplant (LT) recipients.

METHODS

In 317 cases of adult living donor LT (LDLT) performed during 2011, PI developed in three patients during the 3 year follow-up.

RESULTS

Of these three patients, the two who demonstrated PI at 6 weeks and 2 months after LT, respectively, were asymptomatic and showed no signs of secondary complications. Diagnosis was made incidentally using abdominal radiographs and computed tomography (CT) scans. PI was identified in the right ascending colon with concomitant pneumoperitoneum. These two patients received supportive care and maintained a regular diet. Follow-up CT scans demonstrated spontaneous resolution of PI with no complications. The third patient was admitted to the emergency room 30 months after LDLT. His symptoms included poor oral intake and intermittent abdominal pain with no passage of gas. Abdominal radiography and CT scans demonstrated PI in the entire small bowel, with small bowel dilatation, pneumoperitoneum, and pneumoretroperitoneum, but no peritonitis. Physical examination revealed abdominal distension but no tenderness or rebound tenderness. After 1 week of conservative treatment, including bowel rest and antibiotics therapy, PI and pneumoperitoneum resolved spontaneously without complications.

CONCLUSIONS

We suggest that adult LDLT recipients who develop asymptomatic or symptomatic PI with no signs of secondary complications can be successfully managed with conservative treatment.

Long-term survival analysis of liver transplantation for hepatocellular carcinoma with bile duct tumor thrombus

BACKGROUND

Long-term prognosis of liver transplantation (LT) for hepatocellular carcinoma (HCC) with macroscopic bile duct tumor thrombus (BDTT) has not been well assessed. This study intended to analyze the post-transplantation outcomes in patients who had HCC with macroscopic BDTT.

METHODS

A retrospective study was performed with 14 patients who underwent LT for HCC with BDTT (0.7%) after selection from an institutional database of 2052 adult LT cases.

RESULTS

Types of LT were living donor LT in 13 and deceased donor LT in 1. The extents of BDTT were Ueda type 1 in 4, type 2 in 3, and type 3 in 7. Milan criteria were met in 8 (57.1%). Concurrent bile duct resection was performed in 7 (50%). Mean model for end-stage liver disease score was 18.7 ± 4.9. Mean graft-recipient weight ratio was 1.2 ± 0.3. There was one case of perioperative mortality and one case of HCC-unrelated late mortality. Cumulative HCC recurrence rates were 15.4% at 1 year, 46.2% at 3 years, and 46.2% at 5 years. Overall patient survival rates were 92.9% at 1 year, 57.1% at 3 years, and 50% at 5 years. Univariate risk factor analyses revealed that only macrovascular invasion was a significant risk factor for HCC recurrence (P = .019).

CONCLUSIONS

The results of this study revealed that LT for HCC with macroscopic BDTT has a high risk of post-transplantation HCC recurrence; therefore, further large-volume studies are necessary to elucidate the risk factors.

Expression pattern analysis of hepatocellular carcinoma tumor markers in viral hepatitis B and C patients undergoing liver transplantation and resection

BACKGROUND

This study was conducted to compare the expression patterns of serum alpha-fetoprotein (AFP) and proteins induced by vitamin K absence or antagonist-II (PIVKA-II) in hepatocellular carcinoma (HCC) patients undergoing liver transplantation (LT) and resection at a high-volume single institution.

METHODS

First, 663 liver transplant recipients with HCC were selected. They were divided into hepatitis B virus (HBV) (n = 628) and hepatitis C virus (HCV) groups (n = 35). Their medical records were retrospectively reviewed. Second, another cohort of 2709 patients who underwent HCC resection included 2258 HBV, 143 HCV, and 308 non-HBV non-HCV (NBNC) patients.

RESULTS

In the transplantation group, pretransplantation AFP level >20 ng/mL was observed in 42.5% of HBV patients and 60% of HCV patients (P = .042). PIVKA-II level >40 mAU/mL was observed in 30.6% of HBV patients and 42.9% of HCV patients (P = .127). In the resection group, a preoperative AFP level >20 ng/mL was observed in 51.7% of HBV patients and 43.3% of HCV patients (P = .052). PIVKA-II level >40 mAU/mL was observed in 59.7% of HBV patients and 56.6% of HCV patients (P = .47). Preoperative AFP level >20 ng/mL and PIVKA-II level >40 mAU/mL were observed in 35.7% and 61% of NBNC patients, respectively. Receiver-operator characteristic curve analyses revealed that the expression pattern of PIVKA-II in patients with elevated AFP level was not predictable and vice versa, regardless of background liver diseases.

CONCLUSIONS

This study indicates that serum AFP and PIVKA-II may be expressed variably regardless of the types of background liver disease. Further large-volume multicenter studies are needed to evaluate the possibility of the etiology-dependent expression of tumor markers.

External biliary drainage in living donor liver transplantation using duct-to-duct anastomosis

PURPOSE

This study compared the incidence of biliary complication (BC) in adult living donor liver transplant recipients who underwent right-lobe duct-to-duct anastomosis (DDA) with or without external biliary drainage (EBD) and intended to optimize EBD tube clamping.

METHODS

This study consisted of a retrospective assessment of EBD effect and a prospective trial for EBD tube-clamping optimization. The retrospective study included the EBD group (n = 208) and the non-EBD group (n = 145). The prospective study included 60 patients with EBD.

RESULTS

In the retrospective study, single DDA was performed in 83.7% of the EBD group and 80.7% of the non-EBD group (P = .47). One-year overall incidence of BC was 14.4% in the EBD group and 16.8% in the non-EBD group (P = .48). The incidence of early anastomotic bile leakage was 1.0% in the EBD group and 4.8% in the non-EBD group (P = .036). In the prospective study, there was no difference in tube-clamping success rates between low- and high-output EBD groups. There was also no statistical difference between the success and failure groups in terms of graft duct size, liver function tests, and post-transplant days at tube clamping.

CONCLUSIONS

The size of our EBD tube was too small for the graft duct size, therefore its main role appeared to be early biliary decompression, which helped prevent bile leakage and also simplified the route of cholangiogram in detecting early BC. Hence, EBD is worthy of performing in selected patients with a high risk of anastomotic bile leak.

Correlation between mycophenolic acid blood level and renal dysfunction in stable liver transplant recipients receiving mycophenolate monotherapy

PURPOSE

Mycophenolate mofetil (MMF) is frequently used after liver transplantation (OLT). Mycophenolic acid (MPA) metabolites are eliminated primarily via the kidneys. If renal function declines, clearance is significantly impaired. The aim of this study was to reveal the renal function-dependent changes of MPA level in stable adult OLT recipients receiving MMF monotherapy.

METHODS

Sixty-five OLT recipients were selected from our OLT database of >3500 cases. All had undergone MMF monotherapy with a daily MMF dose of 1000 mg or 1500 mg for more than 2 years, primarily because they could not tolerate calcineurin inhibitors. Their clinical profiles, including MPA therapeutic drug monitoring (TDM) and renal function, were analyzed as a cross-sectional study.

RESULTS

For the group treated with 1000 mg MMF (n = 40), the 12-hour MPA trough level was 1.20 ± 0.35 μg/mL with serum creatinine (Cr) level ≤1.4 mg/dL in 13 patients; it was 2.78 ± 1.19 μg/mL with Cr >1.4 mg/dL in 16 patients not undergoing hemodialysis and 3.83 ± 0.87 μg/mL in 11 patients undergoing hemodialysis (P < .001). For the group treated with 1500 mg MMF (n = 25), the MPA trough level was 2.23 ± 0.99 μg/mL with Cr ≤1.4 mg/dL in 6 patients; it was 2.81 ± 0.99 μg/mL with Cr >1.4 mg/dL in 18 patients not undergoing hemodialysis and 3.5 μg/mL in 1 patient undergoing hemodialysis (P = .21).

CONCLUSIONS

Considering the potential therapeutic range of MPA, the suggested MMF dosage for Korean adult OLT recipients requiring hemodialysis may be set around 1000 mg per day. We suggest adjusting the MMF dosage on an individualized basis according to the results of MPA TDM, particularly for patients with markedly impaired renal function.

Effect of reoperation on long-term outcome of pT1b/T2 gallbladder carcinoma after initial laparoscopic cholecystectomy

BACKGROUND

A small proportion of gallbladder carcinomas (GBC) are incidentally detected after laparoscopic cholecystectomy (LC). This study intended to analyze the effect of extended reoperation on the long-term outcome of patients with pT1b/T2 GBC who had initially undergone LC.

METHODS

A cohort of 203 patients who underwent R0 resection and whose pathology was pT1b or pT2 GBC was divided into 3 groups: open surgery (group I, n = 150), LC only (group II, n = 25), and initial LC and subsequent reoperation (group III, n = 28).

RESULTS

Mean ages were 62.3 ± 9.6 years, 65.9 ± 11.8 years, and 57.1 ± 7.7 years in groups I, II, and III, respectively (p = 0.001). The numbers of pT1b and pT2 patients were 75 and 75 in group I, 15 and 10 in group II, and 6 and 22 in group III, respectively. Residual tumors after LC were found in none of 6 pT1b patients and 5 of 22 pT2 patients. Overall 5-year patient survival rate was 70.1 % for all-cause death and 73.5 % for tumor recurrence-associated death (76.0 % in group I, 64.0 % in group II, and 63.0 % in group III [p = 0.607]; 84.4 % in pT1b group I, 68.8 % in pT1b group II, and 83.3 % in pT1b group III [p = 0.649]; 67.6 % in pT2 group I, 50 % in pT2 group II, and 61.9 % in pT2 group III [p = 0.895]). Concurrent bile duct resection in pT2 patients did not affect survival outcomes (p = 0.601).

CONCLUSIONS

No definite survival benefit from reoperation was observed in patients with pT1b lesions. Residual tumor was found in 23 % of pT2 patients after reoperation, and the survival outcomes of these patients were comparable to those of the open surgery group. Therefore, reoperation for pT1b GBC following LC can be individually indicated because its indication remains unclear, but it should be highly recommended for pT2 GBC.

Efficient algorithm to compute mutually connected components in interdependent networks

Mutually connected components (MCCs) play an important role as a measure of resilience in the study of interdependent networks. Despite their importance, an efficient algorithm to obtain the statistics of all MCCs during the removal of links has thus far been absent. Here, using a well-known fully dynamic graph algorithm, we propose an efficient algorithm to accomplish this task. We show that the time complexity of this algorithm is approximately O(N(1.2)) for random graphs, which is more efficient than O(N(2)) of the brute-force algorithm. We confirm the correctness of our algorithm by comparing the behavior of the order parameter as links are removed with existing results for three types of double-layer multiplex networks. We anticipate that this algorithm will be used for simulations of large-size systems that have been previously inaccessible.

Resection of metachronous adrenal metastasis after liver resection and transplantation for hepatocellular carcinoma

BACKGROUND

This study analyzed the patient survival outcomes following the resection of hepatocellular carcinoma (HCC) metachronous adrenal metastasis (MAM) in patients who had undergone liver resection or liver transplantation (LT).

METHODS

Clinical results were analyzed retrospectively in 26 patients with MAM-HCC who underwent adrenalectomy.

RESULTS

The mean interval between initial surgery and adrenalectomy was significantly shorter in the resection group than in the LT group (18.3 ± 14.4 vs. 42.6 ± 13.8 months, p < 0.001). Of 19 resected patients, four had adrenal metastases on the right side, 12 on the left side and three bilaterally, with a mean tumor diameter of 3.6 ± 1.5 cm. Ten of these patients underwent open surgery and nine underwent laparoscopic surgery; all patients experienced recurrences within 18 months and 20.3% survived 5 years after adrenalectomy. Of 7 patients who underwent LT, four had adrenal metastases on the right side and three on the left side, with a mean tumor diameter of 3.4 ± 1.8 cm. Six of these patients underwent open surgery and one underwent laparoscopic surgery. Five-year recurrence and patient survival rates after adrenalectomy were 28.6 and 85.7%, respectively.

CONCLUSIONS

Adrenalectomy is indicated in patients with isolated MAM-HCC. Comparisons with other locoregional treatment modalities and multicenter studies with additional patients are needed to validate the role of adrenalectomy.

Associations between serum 25-hydroxyvitamin D and bone mineral density and proximal femur geometry in Koreans: the Korean National Health and Nutrition Examination Survey (KNHANES) 2008-2009

The association between 25-hydroxyvitamin D (25(OH)D) levels and bone mineral density (BMD) and proximal femur bone geometry was examined in the Korean population. A positive relationship between skeletal health and 25(OH)D levels was observed. However, there were no significant differences in skeletal health between the groups with 25(OH)D level of 50-75 nmol/L and greater than 75 nmol/L.

INTRODUCTION

Vitamin D plays an important role in calcium and phosphate homeostasis and normal mineralization of bone. However, the optimal level of vitamin D for skeletal health has not been clearly established. We analyzed the associations between serum 25(OH)D and BMD and proximal femur bone geometry and determined the optimal 25(OH)D level.

METHODS

This was a cross-sectional study of 10,062 participants (20-95 years, 4,455 men, 5,607 women) in the Fourth Korea National Health and Nutrition Examination Surveys (KNHANES IV) conducted from 2008 to 2009. Participants were divided into groups according to 25(OH)D level (<25, 25-50, 50-75, and ≥75 nmol/L). BMD and proximal femur geometric indices were measured.

RESULTS

The group with 25(OH)D levels of 50-75 nmol/L had greater bone density values, with the exception of the lumbar spine, and also had greater femur neck cortical thickness, cross-sectional area, and cross-sectional moment of inertia, as well as a lesser buckling ratio than the groups with 25(OH)D level of 25-50 nmol/L and less than 25 nmol/L. However, there were no significant differences in BMD and proximal femur geometry properties between the groups with 50-75 nmol/L and greater than 75 nmol/L of 25(OH)D.

CONCLUSION

The skeletal outcomes, including BMD and proximal femur geometric indices observed in this study, suggest that serum 25(OH)D levels of 50 to <75 nmol/L are optimal for skeletal health.

Prevalence analysis of de novo hepatic steatosis following pylorus-preserving pancreaticoduodenectomy

BACKGROUND

Prevalence of hepatic steatosis following pylorus-preserving pancreaticoduodenectomy (PPPD) is high. This study intended to reveal the prevalence and patterns of de novo hepatic steatosis following PPPD.

METHODS

We investigated postoperative de novo hepatic steatosis following PPPD (n = 101) with a control group of bile duct resection (BDR) (n = 54).

RESULTS

At postoperative 1 year, hepatic steatosis occurred in 21 of 82 patients (25.6%) of PPPD group and in 2 of 47 patients (4.3%) of BDR group (p = 0.001). Thereafter, at 2 to 5 years, a high prevalence of hepatic steatosis persisted in the PPPD group, but no further occurrence developed in BDR group. Once steatosis developed, it persisted until the end of the study period or patient death. Five-year cumulative incidence of hepatic steatosis was 26.7% in the PPPD group and 3.7% in BDR group (p < 0.001). Univariate analyses showed that patient sex, age, body mass index, blood lipid profile, recurrence of tumor, and diabetes did not have significant influence on the development of hepatic steatosis following PPPD.

CONCLUSIONS

De novo hepatic steatosis may develop in a not negligible proportion of patients undergone PPPD. Multicenter studies with a high number of patients are needed to elucidate its pathogenesis and to find effective treatment for pancreaticoduodenectomy-associated hepatic steatosis.

Blind and myopic ants in heterogeneous networks

The diffusion processes on complex networks may be described by different Laplacian matrices due to heterogeneous connectivity. Here we investigate the random walks of blind ants and myopic ants on heterogeneous networks: While a myopic ant hops to a neighbor node every step, a blind ant may stay or hop with probabilities that depend on node connectivity. By analyzing the trajectories of blind ants, we show that the asymptotic behaviors of both random walks are related by rescaling time and probability with node connectivity. Using this result, we show how the small eigenvalues of the Laplacian matrices generating the two random walks are related. As an application, we show how the return-to-origin probability of a myopic ant can be used to compute the scaling behaviors of the Edwards-Wilkinson model, a representative model of load balancing on networks.