An additional port in difficult laparoscopic cholecystectomy for surgical safety

BACKGROUND

Tokyo Guidelines 2018, clinical practice guidelines for acute cholangitis and cholecystitis, recommend bailout procedures to prevent bile duct injury (BDI) during laparoscopic cholecystectomy (LC) for difficult gallbladder. We first insert an additional port (AP) for difficult gallbladder that may require bailout procedures. Because the usefulness of an AP during LC is unclear, we therefore examined the efficacy of the AP during LC in this study.

METHODS

Data were collected from 115 patients who underwent LC for acute cholecystitis in our department. The indications for AP were excessive bleeding, scarring, and poor visual field around Calot's triangle. AP was inserted into the right middle abdomen so as not to interfere with other trocars and was used by the assistant. Surgical outcomes were evaluated based on AP use during LC.

RESULTS

AP was inserted in 19 patients during LC (AP group). The indications for AP were excessive bleeding in nine patients, scarring around Calot's triangle in seven patients, and poor visual field around Calot's triangle in three patients. Open conversion was performed in two patients in the non-AP group. BDI occurred in one patient in the non-AP group. In patients with Difficulty Score 3, operation time was significantly shorter (P = .038) and Critical View of Safety (CVS) score was significantly higher in the AP group (P = .046).

CONCLUSION

AP is useful in patients with excessive bleeding to shorten operation time and increase the CVS score. AP may be one useful option for difficult gallbladder.

The Tokyo 2020 terminology of liver anatomy and resections: Updates of the Brisbane 2000 system

BACKGROUND

The Brisbane 2000 Terminology for Liver Anatomy and Resections, based on Couinaud's segments, did not address how to identify segmental borders and anatomic territories of less than one segment. Smaller anatomic resections including segmentectomies and subsegmentectomies, have not been well defined. The advent of minimally invasive liver resection has enhanced the possibilities of more precise resection due to a magnified view and reduced bleeding, and minimally invasive anatomic liver resection (MIALR) is becoming popular gradually. Therefore, there is a need for updating the Brisbane 2000 system, including anatomic segmentectomy or less. An online "Expert Consensus Meeting: Precision Anatomy for Minimally Invasive HBP Surgery (PAM-HBP Surgery Consensus)" was hosted on February 23, 2021.

METHODS

The Steering Committee invited 34 international experts from around the world. The Expert Committee (EC) selected 12 questions and two future research topics in the terminology session. The EC created seven tentative definitions and five recommendations based on the experts' opinions and the literature review performed by the Research Committee. Two Delphi Rounds finalized those definitions and recommendations.

RESULTS

This paper presents seven definitions and five recommendations regarding anatomic segmentectomy or less. In addition, two future research topics are discussed.

CONCLUSIONS

The PAM-HBP Surgery Consensus has presented the Tokyo 2020 Terminology for Liver Anatomy and Resections. The terminology has added definitions of liver anatomy and resections that were not defined in the Brisbane 2000 system.

Minimally invasive anatomic liver resection: Results of a survey of world experts

BACKGROUND

Although the number of minimally invasive liver resections (MILRs) has been steadily increasing in many institutions, minimally invasive anatomic liver resection (MIALR) remains a complicated procedure that has not been standardized. We present the results of a survey among expert liver surgeons as a benchmark for standardizing MIALR.

METHOD

We administered this survey to 34 expert liver surgeons who routinely perform MIALR. The survey contained questions on personal experience with liver resection, inflow/outflow control methods, and identification techniques of intersegmental/sectional planes (IPs).

RESULTS

All 34 participants completed the survey; 24 experts (70%) had more than 11 years of experience with MILR, and over 80% of experts had performed over 100 open resections and MILRs each. Regarding the methods used for laparoscopic or robotic anatomic resection, the Glissonean approach (GA) was a more frequent procedure than the hilar approach (HA). Although hepatic veins were considered essential landmarks, the exposure methods varied. The top three techniques that the experts recommended for identifying IPs were creating a demarcation line, indocyanine green negative staining method, and intraoperative ultrasound.

CONCLUSION

Minimally invasive anatomic liver resection remains a challenging procedure; however, a certain degree of consensus exists among expert liver surgeons.

Expert Consensus Guidelines: How to safely perform minimally invasive anatomic liver resection

BACKGROUND

The concept of minimally invasive anatomic liver resection (MIALR) is gaining popularity. However, specific technical skills need to be acquired to safely perform MIALR. The "Expert Consensus Meeting: Precision Anatomy for Minimally Invasive HBP Surgery (PAM-HBP Surgery Consensus)" was developed as a special program during the 32nd meeting of the Japanese Society of Hepato-Biliary-Pancreatic Surgery (JSHBPS).

METHODS

Thirty-four international experts gathered online for the consensus. A Research Committee performed a comprehensive literature review, classifying studies according to the Scottish Intercollegiate Guidelines Network method. Based on the literature review and experts' opinions, tentative recommendations were drafted and circulated among experts using online Delphi Rounds. Finally, formulated recommendations were presented online in the Expert Consensus Meeting of the JSHBPS on February 23rd, 2021. The final recommendations were validated and finalized by the 2nd Delphi Round in May 2021.

RESULTS

Seven clinical questions were selected, and 22 recommendations were formulated. All recommendations reached more than 85% consensus among experts at the final Delphi Round.

CONCLUSIONS

The Expert Consensus Meeting for safely performing MIALR has presented a set of clinical guidelines based on available literature and experts' opinions. We expect these guidelines to have a favorable effect on the safe implementation and development of MIALR.

Application of a novel surgical difficulty grading system during laparoscopic cholecystectomy

BACKGROUND

Prevention of bile duct injury and vasculo-biliary injury while performing laparoscopic cholecystectomy (LC) is an unsolved problem. Clarifying the surgical difficulty using intraoperative findings can greatly contribute to the pursuit of best practices for acute cholecystitis. In this study, multiple evaluators assessed surgical difficulty items in unedited videos and then constructed a proposed surgical difficulty grading.

METHODS

We previously assembled a library of typical video clips of the intraoperative findings for all LC surgical difficulty items in acute cholecystitis. Fifty-one experts on LC assessed unedited surgical videos. Inter-rater agreement was assessed by Fleiss's κ and Gwet's agreement coefficient (AC).

RESULTS

Except for one item ("edematous change"), κ or AC exceeded 0.5, so the typical videos were judged to be applicable. The conceivable surgical difficulty gradings were analyzed. According to the assessment of difficulty factors, we created a surgical difficulty grading system (agreement probability = 0.923, κ = 0.712, 90% CI: 0.587-0.837; AC₂  = 0.870, 90% CI: 0.768-0.972).

CONCLUSION

The previously published video clip library and our novel surgical difficulty grading system should serve as a universal objective tool to assess surgical difficulty in LC.

Surgical and oncological outcomes of laparoscopic versus open radical antegrade modular pancreatosplenectomy for pancreatic ductal adenocarcinoma

PURPOSE

To compare the outcomes of laparoscopic radical antegrade modular pancreatosplenectomy (L-RAMPS) with those of open RAMPS (O-RAMPS) in patients with pancreatic ductal adenocarcinoma (PDAC).

METHODS

We reviewed, retrospectively, the medical records of 50 patients who underwent RAMPS for PDAC without resection of major vessels and adjacent organs between 2007 and 2019, and analyzed the relationship between the operative method and surgical and oncological outcomes.

RESULTS

Nineteen of the 50 patients underwent L-RAMPS and 31 patients underwent O-RAMPS. L-RAMPS was associated with significantly less blood loss (P = 0.034) but a longer operative time (P = 0.001) than O-RAMPS. There were no significant differences in patient characteristics, tumor factors, or postoperative course; or in the rates of recurrence-free survival (P = 0.084) or overall survival (P = 0.402) between the L-RAMPS and O-RAMPS groups.

CONCLUSION

L-RAMPS for PDAC resulted in less blood loss but a longer operative time than O-RAMPS. Although L-RAMPS may be feasible, the operative time needs to be reduced by standardizing the procedure.

A snapshot of the 2020 conception of anatomic liver resections and their applicability on minimally invasive liver surgery. A preparatory survey for the Expert Consensus Meeting on Precision Anatomy for Minimally Invasive HBP Surgery

BACKGROUND

The main aim of this survey was to analyze how liver surgeons perform liver resections and to define their conception of anatomic procedures within the incorporation of minimally invasive liver surgery (MILS).

METHODS

The survey was distributed among liver surgeons. It mainly focused on personal experience on open and MILS, methods and landmarks, and experience on anatomic resections and Glissonean approach.

RESULTS

A total of 445 valid answers from 54 countries was obtained. Surgeons performing MILS mainly have below 10 years of experience (81.8% of responders) and one third has never done complex MILS. New techniques, including indocyanine green demarcation are marginally used (<25%). More than 60% of surgeons do not make a full exposure of hepatic veins during MILS, mainly due to the risk of injury or not considering it to be of utility. Although 88% of responders agreed with the concept of anatomic resection as the "resection along the border/watersheds of each order division identified by the portal vein flow", only 55% of surgeons have ever performed MILS Glissonean approaches.

CONCLUSIONS

Liver anatomy is not a static concept. Anatomic resections need training and precision. Standardization of complex anatomic resections by a minimally invasive approach should be encouraged.

How Should We Treat Pancreatic Metastases from Renal Cell Carcinoma? A Meta-Analysis

BACKGROUND

The treatment strategy for pancreatic metastasis (PM) from renal cell carcinoma (RCC) is unclear due to its rarity. The aim of this study was to reveal the role of surgery for PM from RCC.

METHODS

A systematic literature search was conducted using PubMed and the Cochrane Library. The effectiveness of surgery for PM was evaluated based on the primary outcome of overall survival (OS), which was investigated in relation to surgical procedures and metastatic sites via subgroup analyses.

RESULTS

There was no significant difference in the rate of 2-year OS between the surgery and control group (OR 0.43, 95% CI 0.14-1.26, P = 0.12). However, the rate of 5-year OS was significantly higher in the surgery group than the control group (OR = 0.41, 95% CI 0.18-0.93, P = 0.03). The rates of the complications and OS were not significantly different between radical and conservative pancreatectomies. The rate of 5-year OS of the patients with PM was higher than that with other metastases (OR 0.38, 95% CI 0.20-0.74, P = 0.004).

CONCLUSION

Surgical resection for PM from RCC is associated with good prognosis. Limited surgery may be a useful option depending on the location of the lesion.

Assembling a library of typical surgery video clips to construct a system for assessing the surgical difficulty of laparoscopic cholecystectomy

BACKGROUND

To explore best practices for acute cholecystitis, it is necessary to construct a system to assess the difficulty of laparoscopic cholecystectomy (LC) based on intraoperative findings. In this study, multiple evaluators assessed videos of LC to assemble a library of typical video clips for 25 intraoperative findings.

METHODS

We have previously identified 25 items that contribute to surgical difficulty in LC. For each item, roughly 30-second video clips were submitted from videos of LC performed at member institutions. We then selected one typical video from the collected clips based on simple tabulation of the instances of agreement. Inter-rater agreement was assessed with Fleiss's κ and Gwet's agreement coefficient (AC).

RESULTS

Except in the case of two assessment items ("edematous change" and "easy bleeding"), κ or AC significantly exceeded 0.5 and the typical videos were judged to be applicable. For the two remaining items, the evaluation was repeated after clarifying the definitions of positive and negative findings. Eventually, they were recognized as typical. The completed video clip library contains 31 clips and is divided into five categories (http://www.jshbps.jp/modules/project/index.php?content_id=13).

CONCLUSIONS

This clip library may be highly useful in clinical settings as a more objective standard for assessing surgical difficulty in LC.

Clinical practice guidelines for the management of liver metastases from extrahepatic primary cancers 2021

BACKGROUND

Hepatectomy is standard treatment for colorectal liver metastases; however, it is unclear whether liver metastases from other primary cancers should be resected or not. The Japanese Society of Hepato-Biliary-Pancreatic Surgery therefore created clinical practice guidelines for the management of metastatic liver tumors.

METHODS

Eight primary diseases were selected based on the number of hepatectomies performed for each malignancy per year. Clinical questions were structured in the population, intervention, comparison, and outcomes (PICO) format. Systematic reviews were performed, and the strength of recommendations and the level of quality of evidence for each clinical question were discussed and determined. The Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach was used to assess evidence and make recommendations.

RESULTS

The eight primary sites were grouped into five categories based on suggested indications for hepatectomy and consensus of the guidelines committee. Fourteen clinical questions were devised, covering five topics: (1) diagnosis, (2) operative treatment, (3) ablation therapy, (4) the eight primary diseases, and (5) systemic therapies. The grade of recommendation was strong for one clinical question and weak for the other 13 clinical questions. The quality of the evidence was moderate for two questions, low for 10, and very low for two. A flowchart was made to summarize the outcomes of the guidelines for the indications of hepatectomy and systemic therapy.

CONCLUSIONS

These guidelines were developed to provide useful information based on evidence in the published literature for the clinical management of liver metastases, and they could be helpful for conducting future clinical trials to provide higher-quality evidence.

Efficacy of releasing impacted gallstones after percutaneous transhepatic gallbladder drainage for acute cholecystitis and consideration of the surgical difficulty during laparoscopic cholecystectomy

INTRODUCTION

Laparoscopic cholecystectomy (LC) is considered difficult in patients with an impacted gallstone (IG). We examined the efficacy of releasing an IG after percutaneous transhepatic gallbladder drainage (PTGBD) for acute cholecystitis (AC) and the usefulness of the Difficulty Score (DS) proposed in the Tokyo Guidelines 2018.

METHODS

Data were collected from 28 patients who underwent LC after PTGBD for AC caused by an IG in our department. The IG was released by flushing the gallbladder with saline or performing cholecystography. Release of the IG was evaluated based on cholecystography or drainage findings. Surgical outcomes were evaluated by comparing whether the IG could be released.

RESULTS

Nine patients had an IG (IG group) and 19 had a released IG at the time of surgery. Operation time was significantly longer (P = .008), Critical View of Safety score was significantly lower (P = .019), and DS was significantly higher (P < .001) in the IG group. In multivariate analysis, DS was the only independent factor for operation time (odds ratio = 8.943, 95% confidence interval 1.179-167.032; P = .033).

CONCLUSION

Releasing an IG may reduce surgical difficulty and maintain surgical safety. DS can be useful in predicting surgical outcomes.

S6 ribosomal protein phosphorylation is associated with malignancy of intraductal papillary mucinous neoplasm of the pancreas

BACKGROUND

Glucose metabolism of intraductal papillary mucinous neoplasms (IPMNs) of the pancreas is unclear. S6 ribosomal protein (S6) phosphorylation is involved not only in controlling cell growth but also in glucose metabolism in cancer. The aim of this study was to investigate the role of S6 phosphorylation and the significance of glucose metabolic changes in IPMN.

METHODS

Records of 39 patients who underwent preoperative FDG-PET and curative resection were enrolled in this study. S6 phosphorylation and GLUT1 expression were evaluated immunohistochemically in these patients. The effect of S6 phosphorylation on glucose uptake was examined in cancer cell lines. To examine the change of glucose metabolism in IPMN clinically, the relation between clinical factors including FDG-PET and malignancy of IPMN was investigated.

RESULTS

S6 phosphorylation and GLUT1 expression were significantly higher in carcinoma than in normal cells or adenoma. Cell lines with high level of S6 phosphorylation showed high glucose uptake, and inhibition of S6 phosphorylation reduced glucose uptake. In clinical examination, FDG-PET was the independent factor related to the diagnosis of adenoma or carcinoma (odds ratio = 20.0, 95% confidence interval = 1.837-539.9, P = .012). FDG-PET detected carcinoma with a sensitivity of 81.8%, specificity of 96.4%, and accuracy of 92.3%.

CONCLUSION

S6 phosphorylation was associated with glucose uptake and malignancy of IPMN. Moreover, glucose uptake increased in malignant cells of IPMN, and FDG-PET is useful for detecting malignancy of IPMN.

Development of an artificial intelligence system using deep learning to indicate anatomical landmarks during laparoscopic cholecystectomy

BACKGROUND

The occurrence of bile duct injury (BDI) during laparoscopic cholecystectomy (LC) is an important medical issue. Expert surgeons prevent intraoperative BDI by identifying four landmarks. The present study aimed to develop a system that outlines these landmarks on endoscopic images in real time.

METHODS

An intraoperative landmark indication system was constructed using YOLOv3, which is an algorithm for object detection based on deep learning. The training datasets comprised approximately 2000 endoscopic images of the region of Calot's triangle in the gallbladder neck obtained from 76 videos of LC. The YOLOv3 learning model with the training datasets was applied to 23 videos of LC that were not used in training, to evaluate the estimation accuracy of the system to identify four landmarks: the cystic duct, common bile duct, lower edge of the left medial liver segment, and Rouviere's sulcus. Additionally, we constructed a prototype and used it in a verification experiment in an operation for a patient with cholelithiasis.

RESULTS

The YOLOv3 learning model was quantitatively and subjectively evaluated in this study. The average precision values for each landmark were as follows: common bile duct: 0.320, cystic duct: 0.074, lower edge of the left medial liver segment: 0.314, and Rouviere's sulcus: 0.101. The two expert surgeons involved in the annotation confirmed consensus regarding valid indications for each landmark in 22 of the 23 LC videos. In the verification experiment, the use of the intraoperative landmark indication system made the surgical team more aware of the landmarks.

CONCLUSIONS

Intraoperative landmark indication successfully identified four landmarks during LC, which may help to reduce the incidence of BDI, and thus, increase the safety of LC. The novel system proposed in the present study may prevent BDI during LC in clinical practice.

A case of ruptured mucinous cystadenoma of the pancreas with recurrence-free survival for 8 years

BACKGROUND

Pancreatic mucinous cystic neoplasm (MCM) presenting with rupture is extremely rare, and very few studies have followed up patients over the long term after ruptured mucinous cystadenoma (MCA). We report a case of ruptured MCA of the pancreas with recurrence-free survival for 8 years.

CASE PRESENTATION

A 28-year-old Japanese woman was admitted to the emergency department of a local hospital after experiencing acute abdominal pain. Abdominal computed tomography revealed massive ascites and the presence of a cystic tumor measuring 60 mm in diameter in the pancreatic tail. Conservative therapy with antibiotics and abdominal drainage were performed to treat peritonitis that occurred secondary to the ruptured pancreatic cystic tumor, after which the patient's symptoms improved. The patient was referred to our department for further examination and treatment. We diagnosed a ruptured MCN and performed laparoscopic spleen-preserving distal pancreatectomy. Histopathological findings revealed ovarian-type stroma, which tested positive for estrogen and progesterone receptors by immunohistochemistry. The histopathological diagnosis was MCA. The postoperative course was uneventful, and the patient remains alive without any evidence of recurrence at 8 years postoperatively.

CONCLUSION

A good prognosis is possible even in cases of ruptured MCA. Because of the risk of peritoneal dissemination after ruptured MCA, long-term follow-up is important.

Altered glycosylation associated with dedifferentiation of hepatocellular carcinoma: a lectin microarray-based study

Background

Altered glycosylation associated with hepatocellular carcinoma (HCC) is well documented. However, few reports have investigated the association between dedifferentiation and glycosylation. Therefore, the aim of this study was to analyze glycosylation associated with dedifferentiation of HCC within the same nodule and to investigate glycosyltransferase related to the glycosylation.

Methods

We analyzed resected HCC specimens (n = 50) using lectin microarray to comprehensively and sensitively analyze glycan profiles, and identify changes to glycosylation between well- and moderately-differentiated components within the same nodule. Moreover, we performed immunohistochemical staining of mannosyl(α-1,3-)-glycoprotein β-1,2-N-acetylglucosaminyltransferase (MGAT1), which is an essential glycosyltransferase that converts high-mannose glycans to complex- or hybrid-type N-glycans.

Results

Four lectins from Narcissus pseudonarcissus agglutinin (NPA), Concanavalin A, Galanthus nivalis agglutinin, and Calystegia sepium agglutinin were significantly elevated in moderately-differentiated components of HCC compared with well-differentiated components, and all lectins showed binding specificity to high-mannose glycans. Therefore, these structures were represented to a greater extent in moderately-differentiated components than in well-differentiated ones. Immunohistochemical staining revealed significantly increased NPA expression and decreased MGAT1 expression in moderately-differentiated components. Low MGAT1 expression in moderately-differentiated components of tumors was associated with intrahepatic metastasis and had tendency for poor prognosis.

Conclusion

Dedifferentiation of well-differentiated HCC is associated with an increase in high-mannose glycans. MGAT1 may play a role in the dedifferentiation of HCC.

Fucosyltransferase 8 plays a crucial role in the invasion and metastasis of pancreatic ductal adenocarcinoma

PURPOSE

Pancreatic ductal adenocarcinoma (PDAC) is the most common type of pancreatic cancer. It is an aggressive malignancy associated with poor prognosis because of recurrence, metastasis, and treatment resistance. Aberrant glycosylation of cancer cells triggers their migration and invasion and is considered one of the most important prognostic cancer biomarkers. The current study aimed to identify glycan alterations and their relationship with the malignant potential of PDAC.

METHODS

Using a lectin microarray, we evaluated glycan expression in 62 PDAC samples. Expression of fucosyltransferase 8 (FUT8), the only enzyme catalyzing core fucosylation, was investigated by immunohistochemistry. The role of FUT8 in PDAC invasion and metastasis was confirmed using an in vitro assay and a xenograft peritoneal metastasis mouse model.

RESULTS

The microarray data demonstrated that core fucose-binding lectins were significantly higher in carcinoma than in normal pancreatic duct tissues. Similarly, FUT8 protein expression was significantly higher in carcinoma than in normal pancreatic duct tissues. High FUT8 protein expression was significantly associated with lymph-node metastases and relapse-free survival. FUT8 knockdown significantly reduced the invasion in PDAC cell lines and impaired peritoneal metastasis in the xenograft model.

CONCLUSIONS

The findings of this study provide evidence that FUT8 plays a pivotal role in PDAC invasion and metastasis and might be a therapeutic target for this disease.

Pharmacokinetic and toxicodynamic evaluation of 5-fluorouracil administration after major hepatectomy in a rat model

BACKGROUND

Chemotherapy after hepatectomy for colorectal liver metastasis has not been established, due to the toxic side effects, which are likely related to impaired drug clearance during liver regeneration. We investigated the pharmacokinetic and toxicodynamic evaluation of 5-fluorouracil (5-FU) during liver regeneration after major hepatectomy in a rat model.

METHODS

Thirty-six male Wistar rats were divided into control (C), control with chemotherapy (CC), hepatectomy (H), and hepatectomy with chemotherapy (HC) groups. The CC and HC groups were administered 5-FU for 4 days. Plasma 5-FU, liver weight, and liver dihydropyrimidine dehydrogenase (DPD) were measured. The ileal villous height was measured to determine adverse effects.

RESULTS

The area under the curve and maximum plasma concentration of 5-FU increased by up to 51% and 32%, respectively, in the HC group compared to the CC group. The liver regeneration rate was significantly lower in the HC group than in the H group (67.3 ± 7.4 vs 33.0 ± 5.7%, p < 0.001). The HC group had a significantly lower liver DPD than the CC group (4.4 ± 1.1 mg vs 6.9 ± 1.1 mg, p < 0.01). The HC group had a significantly lower ileal villous height than the CC group (253 ± 40 μm vs. 318 ± 36 μm, p < 0.05).

CONCLUSIONS

Reduction of the total liver DPD following major hepatectomy caused increased plasma 5-FU levels and 5-FU-associated toxicity.

[IPMC of the pancreas with enlarged para-aortic lymph nodes with a high accumulation of FDG-PET:a case report]

A 74-year-old man was admitted for evaluation of a pancreatic tumor. Abdominal CT revealed a multilocular cystic tumor with thickened septal walls and an enhanced mural nodule in the head of the pancreas, as well as enlarged para-aortic lymph nodes. FDG-PET revealed FDG accumulation in the nodule and in the para-aortic nodes. The tumor was diagnosed as intraductal papillary mucinous carcinoma (IPMC) with para-aortic lymph node metastases. After 2 courses of chemotherapy with gemcitabine and nab-paclitaxel, the tumor decreased slightly in size, but the lymph nodes did not change. Surgery was then performed. Intraoperative pathology examination confirmed that the para-aortic lymph nodes had only inflammatory swelling. Accordingly, pylorus-preserving pancreaticoduodenectomy was performed. Histopathology examination revealed atypical cells without invasion, and IPMC (TisN0M0;stage 0) was diagnosed. It is thus important for selection of the appropriate treatment approach to determine if enlarged para-aortic lymph nodes are benign or malignant.

Improvement of non-alcoholic fatty liver disease after laparoscopic sleeve gastrectomy in Japanese obese patients

PURPOSE

The purpose of this study was to evaluate changes in non-alcoholic fatty liver disease (NAFLD) after laparoscopic sleeve gastrectomy (LSG) using computed tomography (CT) images.

METHODS

We analyzed data from 57 patients who underwent LSG and had CTs performed before and after surgery. The patients included 34 women and 23 men (with an average age of 43 years); their mean preoperative weight and body mass index were 120 kg and 46 kg/m2, respectively. Obesity-related health disorders included type 2 diabetes mellitus (T2DM) in 33 patients, hypertension in 33 and dyslipidemia in 32. We diagnosed NAFLD in cases with liver to spleen ratios (L/S ratio) <0.9 on non-contrast CT images. We evaluated changes in body weights, BMIs, comorbidities, metabolic parameters, L/S ratios, and liver volumes after surgery.

RESULTS

The mean interval between CT scans before and after surgery was 26 months. The total weight loss and % excess weight loss were 35 kg and 72%, respectively. The remission rates for T2DM, hypertension, and dyslipidemia were 85%, 76% and 84%, respectively. After LSG, the L/S ratio increased in all the patients, while all except for one had L/S ratio >0.9. We diagnosed 33 out of 57 patients (58%) as having NAFLD before the operation. After the operation, the L/S ratios and liver volumes were not statistically different between the patients with previous NAFLD and those without it.

CONCLUSION

Laparoscopic sleeve gastrectomy is an effective treatment for obesity-related health disorders including NAFLD in Japanese obese patients.

Pylorus-preserving pancreatoduodenectomy preserving the right gastroepiploic vessels following proximal gastrectomy: report of two cases

BACKGROUND

Blood flow of the remnant stomach is supplied via the right gastric and right gastroepiploic vessels after proximal gastrectomy (PG). Whether the remnant stomach can be safely preserved in patients who undergo pylorus-preserving pancreatoduodenectomy (PPPD) after PG remains unclear. We herein report two cases in which the remnant stomach was safely preserved by performing PPPD.

CASE PRESENTATION

The first patient, a 76-year-old man, was diagnosed with cancer of the common bile duct and underwent PPPD 2 years after PG for gastric cancer. The remnant stomach and right gastroepiploic vessels were safely preserved. The second patient, a 56-year-old man with a history of PG for gastric cancer 20 years previously, was diagnosed with cancer of the common bile duct and underwent PPPD. We could safely preserve the remnant stomach and right gastroepiploic vessels.

CONCLUSION

The remnant stomach could be preserved in performing PPPD following PG by preserving the right gastroepiploic vessels.

First Measurement of a Long-Lived π^{+}π^{-} Atom Lifetime

The adapted DIRAC experiment at the CERN PS accelerator observed for the first time long-lived hydrogenlike π^{+}π^{-} atoms, produced by protons hitting a beryllium target. A part of these atoms crossed the gap of 96 mm between the target and a 2.1  μm thick platinum foil, in which most of them dissociated. Analyzing the observed number of atomic pairs, n_{A}^{L}=436_{-61}^{+157}|_{tot}, the lifetime of the 2p state is found to be τ_{2p}=(0.45_{-0.30}^{+1.08}|_{tot})×10^{-11}  s, not contradicting the corresponding QED 2p state lifetime τ_{2p}^{QED}=1.17×10^{-11}  s. This lifetime value is three orders of magnitude larger than our previously measured value of the π^{+}π^{-} atom ground state lifetime τ=(3.15_{-0.26}^{+0.28}|_{tot})×10^{-15}  s. Further studies of long-lived π^{+}π^{-} atoms will allow us to measure energy differences between p and s atomic states and so to discriminate between the isoscalar and isotensor ππ scattering lengths with the aim to check QCD predictions.

Laparoscopic narrowband imaging for intraoperative diagnosis of the depth of invasion of gallbladder carcinoma: a preliminary study

Highlight Iwashita and Inomata present the findings of a preliminary study regarding laparoscopic narrow-band imaging observations of gallbladder carcinoma - a novel intraoperative diagnostic method that can indicate the depth of cancer invasion. They propose that this approach can improve intraoperative diagnostic performance and aid the selection of optimal therapeutic strategies.

Training System for Endoscopic Surgery Aiming to Provide the Sensation of Forceps Operation

In Japan, a rising number of endoscopic surgery operations have boosted an expectation for the development of a training environment for qualified surgeons. The endoscopic surgery operation requires the operator to operate forceps by hand based on two-dimensional operative field information displayed on the monitor. The characteristics of the operation include a lack of stereoscopic visual field information and movement of the tip of the forceps, which is symmetric about the trocar. These are issues that require an empirical solution from the operator. It is desirable that these issues have already been overcome before the operator starts practicing as an operating surgeon. To this end, it is effective to train the operator in the sensation of forceps operation, which associates the operative field vision with the forceps operation by hand. Therefore, this study includes digitizing the forceps operation by qualified surgeons and providing it to the trainee as visual and force information in order to build a training device that facilitates the cultivation of the sensation of forceps operation.

Secondary Unconjugated Bile Acids Induce Hepatic Stellate Cell Activation

Hepatic stellate cells (HSCs) are key players in liver fibrosis, cellular senescence, and hepatic carcinogenesis. Bile acids (BAs) are involved in the activation of HSCs, but the detailed mechanism of this process remains unclear. We conducted a comprehensive DNA microarray study of the human HSC line LX-2 treated with deoxycholic acid (DCA), a secondary unconjugated BA. Additionally, LX-2 cells were exposed to nine BAs and studied using immunofluorescence staining, enzyme-linked immunosorbent assay, and flow cytometry to examine the mechanisms of HSC activation. We focused on the tumor necrosis factor (TNF) pathway and revealed upregulation of genes related to nuclear factor kappa B (NF-κB) signaling and senescence-associated secretory phenotype factors. α-Smooth muscle actin (α-SMA) was highly expressed in cells treated with secondary unconjugated BAs, including DCA, and a morphological change associated with radial extension of subendothelial protrusion was observed. Interleukin-6 level in culture supernatant was significantly higher in cells treated with secondary unconjugated BAs. Flow cytometry showed that the proportion of cells highly expressing α-SMA was significantly increased in HSCs cultured with secondary unconjugated BAs. We demonstrated that secondary unconjugated BAs induced the activation of human HSCs.

Prognostic factors of non-ampullary duodenal adenocarcinoma

Background

Non-ampullary duodenal adenocarcinoma, excluding carcinoma in the ampulla of Vater, is a rare disease. Although several prognostic factors have been reported, they remain controversial due to the rarity of non-ampullary duodenal adenocarcinoma. The aims of this study were to investigate prognostic factors in patients with non-ampullary duodenal adenocarcinoma and to assess chemotherapy in patients with recurrence.

Patients and methods

Records of 25 patients who underwent surgical treatment for non-ampullary duodenal adenocarcinoma from 2004 to 2016 were retrospectively reviewed. The relationship between the clinicopathological factors and outcomes was investigated.

Results

Serum level of CA19-9, gross appearance, tumor size, tumor invasion, lymph node metastases, TNM stage and lymphatic and vascular invasion were significant risk factors of recurrence. Patients with recurrence who received chemotherapy according to regimens used to treat colorectal cancer had a better prognosis than those without chemotherapy (P = 0.016).

Conclusion

Advanced non-ampullary duodenal adenocarcinoma has a poor prognosis, but chemotherapy possibly improves the prognosis in the patients with recurrent non-ampullary duodenal adenocarcinoma.

Control of inferior vena cava injury during laparoscopic surgery using a double balloon-equipped central venous catheter: proof of concept in a live porcine model

BACKGROUND

Iatrogenic inferior vena cava (IVC) injury is a rare but potentially life-threatening complication during laparoscopic surgery. This experimental study aimed to assess the hemostatic ability of a new device, double balloon-equipped central venous (DB-CV) catheter, for IVC injury.

METHODS

The DB-CV catheter comprises a triple-lumen sphincterotome combined with two dilating balloons having a diameter of 25 mm. The experimental procedures were performed in five pigs. The DB-CV catheter was inserted via the right femoral vein. For the IVC occlusion test, correct placement of the balloons was confirmed by indocyanine green fluorescence imaging, and hemodynamic data were recorded. For the IVC injury test, a 3- to 4-mm circumferential incision was created in IVC, and hemostasis was initiated using balloon inflation 5 s after the injury.

RESULTS

Hemodynamic changes were minimal, with a 20 mmHg reduction in the mean arterial pressure because of IVC occlusion. All bleeding from IVC injuries was successfully temporarily stopped by direct balloon compression, with a mean time to hemostasis of 69 s and mean blood loss of 32 ml. Subsequently, the positioning of IVC injuries between two balloons made it possible to suture the injured IVC.

CONCLUSIONS

Balloon occlusion using the DB-CV catheter provides a rapid temporal hemostatic effect and can overcome the serious condition of massive hemorrhage from IVC injuries.

Tokyo Guidelines 2018: surgical management of acute cholecystitis: safe steps in laparoscopic cholecystectomy for acute cholecystitis (with videos)

In some cases, laparoscopic cholecystectomy (LC) may be difficult to perform in patients with acute cholecystitis (AC) with severe inflammation and fibrosis. The Tokyo Guidelines 2018 (TG18) expand the indications for LC under difficult conditions for each level of severity of AC. As a result of expanding the indications for LC to treat AC, it is absolutely necessary to avoid any increase in bile duct injury (BDI), particularly vasculo-biliary injury (VBI), which is known to occur at a certain rate in LC. Since the Tokyo Guidelines 2013 (TG13), an attempt has been made to assess intraoperative findings as objective indicators of surgical difficulty; based on expert consensus on these difficulty indicators, bail-out procedures (including conversion to open cholecystectomy) have been indicated for cases in which LC for AC is difficult to perform. A bail-out procedure should be chosen if, when the Calot's triangle is appropriately retracted and used as a landmark, a critical view of safety (CVS) cannot be achieved because of the presence of nondissectable scarring or severe fibrosis. We propose standardized safe steps for LC to treat AC. To achieve a CVS, it is vital to dissect at a location above (on the ventral side of) the imaginary line connecting the base of the left medial section (Segment 4) and the roof of Rouvière's sulcus and to fulfill the three criteria of CVS before dividing any structures. Achieving a CVS prevents the misidentification of the cystic duct and the common bile duct, which are most commonly confused. Free full articles and mobile app of TG18 are available at: http://www.jshbps.jp/modules/en/index.php?content_id=47. Related clinical questions and references are also included.

Tokyo Guidelines 2018: diagnostic criteria and severity grading of acute cholecystitis (with videos)

The Tokyo Guidelines 2013 (TG13) for acute cholangitis and cholecystitis were globally disseminated and various clinical studies about the management of acute cholecystitis were reported by many researchers and clinicians from all over the world. The 1^st edition of the Tokyo Guidelines 2007 (TG07) was revised in 2013. According to that revision, the TG13 diagnostic criteria of acute cholecystitis provided better specificity and higher diagnostic accuracy. Thorough our literature search about diagnostic criteria for acute cholecystitis, new and strong evidence that had been released from 2013 to 2017 was not found with serious and important issues about using TG13 diagnostic criteria of acute cholecystitis. On the other hand, the TG13 severity grading for acute cholecystitis has been validated in numerous studies. As a result of these reviews, the TG13 severity grading for acute cholecystitis was significantly associated with parameters including 30-day overall mortality, length of hospital stay, conversion rates to open surgery, and medical costs. In terms of severity assessment, breakthrough and intensive literature for revising severity grading was not reported. Consequently, TG13 diagnostic criteria and severity grading were judged from numerous validation studies as useful indicators in clinical practice and adopted as TG18/TG13 diagnostic criteria and severity grading of acute cholecystitis without any modification. Free full articles and mobile app of TG18 are available at: http://www.jshbps.jp/modules/en/index.php?content_id=47. Related clinical questions and references are also included.

Tokyo Guidelines 2018: antimicrobial therapy for acute cholangitis and cholecystitis

Antimicrobial therapy is a mainstay of the management for patients with acute cholangitis and/or cholecystitis. The Tokyo Guidelines 2018 (TG18) provides recommendations for the appropriate use of antimicrobials for community-acquired and healthcare-associated infections. The listed agents are for empirical therapy provided before the infecting isolates are identified. Antimicrobial agents are listed by class-definitions and TG18 severity grade I, II, and III subcategorized by clinical settings. In the era of emerging and increasing antimicrobial resistance, monitoring and updating local antibiograms is underscored. Prudent antimicrobial usage and early de-escalation or termination of antimicrobial therapy are now important parts of decision-making. What is new in TG18 is that the duration of antimicrobial therapy for both acute cholangitis and cholecystitis is systematically reviewed. Prophylactic antimicrobial usage for elective endoscopic retrograde cholangiopancreatography is no longer recommended and the section was deleted in TG18. Free full articles and mobile app of TG18 are available at: http://www.jshbps.jp/modules/en/index.php?content_id=47. Related clinical questions and references are also included.

Tokyo Guidelines 2018: management bundles for acute cholangitis and cholecystitis

Management bundles that define items or procedures strongly recommended in clinical practice have been used in many guidelines in recent years. Application of these bundles facilitates the adaptation of guidelines and helps improve the prognosis of target diseases. In Tokyo Guidelines 2013 (TG13), we proposed management bundles for acute cholangitis and cholecystitis. Here, in Tokyo Guidelines 2018 (TG18), we redefine the management bundles for acute cholangitis and cholecystitis. Critical parts of the bundles in TG18 include the diagnostic process, severity assessment, transfer of patients if necessary, and therapeutic approach at each time point. Observance of these items and procedures should improve the prognosis of acute cholangitis and cholecystitis. Studies are now needed to evaluate the dissemination of these TG18 bundles and their effectiveness. Free full articles and mobile app of TG18 are available at: http://www.jshbps.jp/modules/en/index.php?content_id=47. Related clinical questions and references are also included.

Delphi consensus on bile duct injuries during laparoscopic cholecystectomy: an evolutionary cul-de-sac or the birth pangs of a new technical framework?

Bile duct injury (BDI) during laparoscopic cholecystectomy remains a serious iatrogenic surgical complication. BDI most often occurs as a result of misidentification of the anatomy; however, clinical evidence on its precise mechanism and surgeons' perceptions is scarce. Surgeons from Japan, Korea, Taiwan, and the USA, etc. (n = 614) participated in a questionnaire regarding their BDI experience and near-misses; and perceptions on landmarks, intraoperative findings, and surgical techniques. Respondents voted for a Delphi process and graded each item on a five-point scale. The consensus was built when ≥80% of overall responses were 4 or 5. Response rates for the first- and second-round Delphi were 60.6% and 74.9%, respectively. Misidentification of local anatomy accounted for 76.2% of BDI. Final consensus was reached on: (1) Effective retraction of the gallbladder, (2) Always obtaining critical view of safety, and (3) Avoiding excessive use of electrocautery/clipping as vital procedures; and (4) Calot's triangle area and (5) Critical view of safety as important landmarks. For (6) Impacted gallstone and (7) Severe fibrosis/scarring in Calot's triangle, bail-out procedures may be indicated. A consensus was reached among expert surgeons on relevant landmarks and intraoperative findings and appropriate surgical techniques to avoid BDI.

Fusion anomaly of the pancreatic tail and spleen: a case report

BACKGROUND

Splenopancreatic fusion is a rare anomaly that is often associated with trisomy 13. Its diagnosis can be important in patients scheduled to undergo distal pancreatectomy or splenectomy, to avoid possible intraoperative or postoperative complications.

CASE PRESENTATION

An 82-year-old Japanese man was referred to our hospital for further evaluation and treatment for a solitary hepatocellular carcinoma based on liver cirrhosis. Triple-phase contrast-enhanced multidetector-row computed tomography and magnetic resonance imaging showed a splenopancreatic fusion as well as a solitary hepatocellular carcinoma in segment VIII of his liver.

CONCLUSIONS

Fusion of the pancreatic tail and spleen is a rare and asymptomatic anomaly. Its detection can be improved by the use of multidetector computed tomography or magnetic resonance imaging.

Long-term outcomes of laparoscopic versus open splenectomy for immune thrombocytopenia

PURPOSE

Splenectomy is the standard therapy for medically refractory immune thrombocytopenia (ITP). Laparoscopic splenectomy (LS) has gained wide acceptance; however, the long-term outcomes of LS versus open splenectomy (OS) for patients with ITP remain unclear.

METHODS

We analyzed, retrospectively, 32 patients who underwent splenectomy, as LS in 22 and OS in 10, for refractory ITP at our institute. Data were evaluated based on the American Society of Hematology 2011 evidence-based practice guidelines for ITP.

RESULTS

Although the operation time was significantly longer in the LS group (p < 0.01), LS was associated with less blood loss (p < 0.01), infrequent blood transfusion during surgery (p < 0.01), quicker resumption of oral intake (p < 0.01), and shorter hospital stay (p < 0.01) than OS. Positive responses, including complete and partial remission, were achieved in 90% of the OS group patients and 77% of the LS group patients. The mean follow-up periods were 183 and 92 months, respectively. Relapse-free survival rates, 15 years after the operation were 63% in the OS group and 94% in the LS group.

CONCLUSIONS

LS can provide better short-term results and comparable long-term results to those of OS for ITP.

Remyelination of Demyelinated CNS Axons by Transplanted Human Schwann Cells: The Deleterious Effect of Contaminating Fibroblasts

Areas of demyelination can be remyelinated by transplanting myelin-forming cells. Schwann cells are the naturally remyelinating cells of the peripheral nervous system and have a number of features that may make them attractive for cell implantation therapies in multiple sclerosis, in which spontaneous but limited Schwann cell remyelination has been well documented. Schwann cells can be expanded in vitro, potentially affording the opportunity of autologous transplantation; and they might also be spared the demyelinating process in multiple sclerosis. Although rat, cat, and monkey Schwann cells have been transplanted into rodent demyelinating lesions, the behavior of transplanted human Schwann cells has not been evaluated. In this study we examined the consequences of injecting human Schwann cells into areas of acute demyelination in the spinal cords of adult rats. We found that transplants containing significant fibroblast contamination resulted in deposition of large amounts of collagen and extensive axonal degeneration. However, Schwann cell preparations that had been purified by positive immunoselection using antibodies to human low-affinity nerve growth factor receptor containing less than 10% fibroblasts were associated with remyelination. This result indicates that fibroblast contamination of human Schwann cells represents a greater problem than would have been appreciated from previous studies.

Observation of π^{-}K^{+} and π^{+}K^{-} Atoms

The observation of hydrogenlike πK atoms, consisting of π^{-}K^{+} or π^{+}K^{-} mesons, is presented. The atoms are produced by 24  GeV/c protons from the CERN PS accelerator, interacting with platinum or nickel foil targets. The breakup (ionization) of πK atoms in the same targets yields characteristic πK pairs, called "atomic pairs," with small relative momenta Q in the pair center-of-mass system. The upgraded DIRAC experiment observed 349±62 such atomic πK pairs, corresponding to a signal of 5.6 standard deviations. This is the first statistically significant observation of the strange dimesonic πK atom.

Laparoscopic caudal approach for a small hepatocellular carcinoma located in the paracaval portion of a cirrhotic liver

Resection of a tumor located in the paracaval portion of the liver, without sacrificing other parts of the liver, is surgically challenging. Here, we describe using a laparoscopic caudal approach for a small hepatocellular carcinoma located in the paracaval portion. It is the first case using the laparoscopic caudal approach to be reported in the literature. Compared with the conventional approaches, this procedure can minimize both surgical invasiveness and the volume of liver parenchyma to be resected. In addition, the laparoscopic view is suitable for this procedure. The laparoscopic caudal approach can be a safe procedure with minimal invasiveness for a small paracaval tumor, particularly in patients with liver cirrhosis.

Clinical Utility of the Difficulty Scoring System for Predicting Surgical Time of Laparoscopic Liver Resection

INTRODUCTION

Laparoscopic liver resection (LLR) has several problems, such as technical complexity and patient and tumor factors. A difficulty scoring system to preoperatively evaluate the difficulty of LLR was established at the second International Consensus Conference on Laparoscopic Liver Resection. The aim of this study was to explore the clinical usefulness of the difficulty scoring system for LLR.

PATIENTS AND METHODS

From January 2010 to June 2015, the records of 78 patients who had undergone LLR were retrospectively reviewed. The patients' data were used to assign a difficulty score, and the correlations between scores and surgical outcomes were investigated.

RESULTS

The mean surgical time was 256 minutes, and the mean blood loss was 168 mL. The difficulty score significantly correlated with surgical time and blood loss, but not with morbidity and postoperative hospital stay. Multivariate analysis showed that the difficulty score was an independent predictor of prolonged surgical time.

CONCLUSIONS

The difficulty score was found to be an effective predictor of surgical time for LLR.

Benefit of laparoscopic liver resection in high body mass index patients

AIM: To explore the impact of body mass index (BMI) on surgical outcomes in patients undergoing laparoscopic liver resection (LLR).

METHODS: From January 2010 to February 2015, sixty-eight patients who underwent primary partial liver resection in our institute were retrospectively reviewed. Surgical outcomes of LLR were compared with those of open liver resection (OLR). In addition, we analyzed associations with BMI and surgical outcomes.

RESULTS: Among 68 patients, thirty-nine patients underwent LLR and 29 were performed OLR. Significant difference in operation time, blood loss, and postoperative hospital stay was observed. There were no significant differences in mortality and morbidity in two groups. Twenty-two patients (32.4%) were classified as obese (BMI ≥ 25). A statistically significant correlation was observed between BMI and operation time, between BMI and blood loss in OLR, but not in LLR. The operation time and blood loss of OLR were significantly higher than that of LLR in obese patients. Open liver resection and BMI were independent predictors for prolonged operation time and increased blood loss in multivariate analysis.

CONCLUSION: The present study demonstrated that BMI had influenced to surgical outcomes of OLR. LLR was less influenced by BMI and had great benefit in obese patients.