A multi-institutional study designed by members of Tokyo Guidelines (TG) Core Meeting to elucidate the clinical characteristics and pathogenesis of acute cholangitis after bilioenteric anastomosis and biliary stent insertion with a focus on biliary obstruction: Role of transient hepatic attenuation difference (THAD) and pneumobilia in improving TG diagnostic performance.

BACKGROUND/PURPOSE: The aim of this study was to clarify the clinical characteristics of acute cholangitis (AC) after bilioenteric anastomosis and stent-related AC in a multi-institutional retrospective study, and validate the TG18 diagnostic performance for various type of cholangitis. METHODS: We retrospectively reviewed 1079 AC patients during 2020, at 16 Tokyo Guidelines 18 (TG 18) Core Meeting institutions. Of these, the post-biliary reconstruction associated AC (PBR-AC), stent-associated AC (S-AC) and common AC (C-AC) were 228, 307, and 544, respectively. The characteristics of each AC were compared, and the TG18 diagnostic performance of each was evaluated. RESULTS: The PBR-AC group showed significantly milder biliary stasis compared to the C-AC group. Using TG18 criteria, definitive diagnosis rate in the PBR-AC group was significantly lower than that in the C-AC group (59.6% vs. 79.6%, p < .001) because of significantly lower prevalence of TG 18 imaging findings and milder bile stasis. In the S-AC group, the bile stasis was also milder, but definitive-diagnostic rate was significantly higher (95.1%) compared to the C-AC group. The incidence of transient hepatic attenuation difference (THAD) and pneumobilia were more frequent in PBR-AC than that in C-AC. The definitive-diagnostic rate of PBR-AC (59.6%-78.1%) and total cohort (79.6%-85.3%) were significantly improved when newly adding these items to TG18 diagnostic imaging findings. CONCLUSIONS: The diagnostic rate of PBR-AC using TG18 is low, but adding THAD and pneumobilia to TG imaging criteria may improve TG diagnostic performance.

A nationwide certification system to increase the safety of highly advanced hepatobiliary-pancreatic surgery.

BACKGROUND: To ensure that highly advanced hepatobiliary-pancreatic surgery (HBPS) is performed safely, the Japanese Society of Hepato-Biliary-Pancreatic Surgery (JSHBPS) board certification system for expert surgeons established a safety committee to monitor surgical safety. METHODS: We investigated postoperative mortality rates based on summary reports of numbers and outcomes of highly advanced HBPS submitted annually by the board-certified training institutions from 2012 to 2019. We also analyzed summary reports on mortality cases submitted by institutions with high 90-day post-HBPS mortality rates and recommended site visits and surveys as necessary. RESULTS: Highly advanced HBPS was performed in 121 518 patients during the 8-year period. Thirty-day mortality rates from 2012 to 2019 were 0.92%, 0.8%, 0.61%, 0.63%, 0.70%, 0.59%, 0.48%, and 0.52%, respectively (P < .001). Ninety-day mortality rates were 2.1%, 1.82%, 1.62%, 1.28%, 1.46%, 1.22%, 1.19%, and 0.98%, respectively (P < .001). Summary reports were submitted by 20 hospitals between 2015 and 2019. Mortality rates before and after the start of report submission and audit were 5.72% and 2.79%, respectively (odds ratio 0.690, 95% confidence interval 0.487-0.977; P = .037). CONCLUSIONS: Development of a system for designation of board-certified expert surgeons and safety management improved the mortality rate associated with highly advanced HBPS.

Clinical outcomes of organ-preserving pancreatectomy for benign or low-grade malignant pancreatic tumors: A multicenter nationwide survey in Japan.

BACKGROUND/PURPOSE: Whether organ-preserving pancreatic surgery has an advantage in postoperative short- and long-term outcomes or not is still unknown because only small case series studies have been available to date. In this multicenter retrospective study, we aimed to elucidate the clinical advantage and disadvantage of organ-preserving pancreatectomy among patients with low-grade malignant pancreatic tumors and benign pancreatic diseases. METHODS: We included patients diagnosed with benign or low-malignant pancreatic tumor who underwent pancreaticoduodenectomy (PD) in 621 cases, duodenum-preserving pancreatic head resection (DPPHR) in 31 cases, middle pancreatectomy (MP) in 148 cases, distal pancreatectomy (DP) in 814 cases, and spleen-preserving distal pancreatectomy (SPDP) in 259 cases between January 1, 2013, and December 31, 2017. Preoperative backgrounds, surgical outcomes and pre- and postoperative (3, 6, 12, 24, and 36 months) nutritional status were compared between these procedures. RESULTS: In terms of short-term outcomes, the incidence of pancreatic fistula in patients who underwent MP was significantly higher than in patients with standard pancreatectomy. As for the long-term pancreatic functions in the cases of head or body lesion, both exocrine and endocrine functions after MP were significantly favorable compared with the PD group from 3 to 36 months after surgery. In pancreatic body or tail lesion, significant advantage of endocrine function, but not exocrine function, was found in the MP group compared to standard DP at all time points. CONCLUSIONS: MP may contribute to the improvement of postoperative quality of life for patients with pancreatic body low-malignant tumors, rather than PD or DP; however, reducing the incidence of short-term complications such as pancreatic fistula is a future challenge.

JPN clinical practice guidelines 2021 with easy-to-understand explanations for the management of acute pancreatitis.

BACKGROUND: In preparing the Japanese (JPN) guidelines for the management of acute pancreatitis 2021, the committee focused the issues raised by the results of nationwide epidemiological survey in 2016 in Japan. METHOD: In addition to a systematic search using the previous JPN guidelines, papers published from January 2014 to September 2019 were searched for the contents to be covered by the guidelines based on the concept of GRADE system. RESULTS: Thirty-six clinical questions (CQ) were prepared in 15 subject areas. Based on the facts that patients diagnosed with severe disease by both Japanese prognostic factor score and contrast-enhanced computed tomography (CT) grade had a high fatality rate and that little prognosis improvement after 2 weeks of disease onset was not obtained, we emphasized the importance of Pancreatitis Bundles, which were shown to be effective in improving prognosis, and the CQ sections for local pancreatic complications had been expanded to ensure adoption of a step-up approach. Furthermore, on the facts that enteral nutrition for severe acute pancreatitis was not started early within 48 h of admission and that unnecessary prophylactic antibiotics was used in almost all cases, we emphasized early enteral nutrition in small amounts even if gastric feeding is used and no prophylactic antibiotics are administered in mild pancreatitis. CONCLUSION: All the members of the committee have put a lot of effort into preparing the extensively revised guidelines in the hope that more people will have a common understanding and that better medical care will be spread.

Modified Socratic Method (planned and executed by Takada) for medical education: Grade II Acute Cholecystitis of Tokyo Guidelines 2018 as an example case.

BACKGROUND: Socratic method, which is an educational method to promote critical thinking through a dialogue, has never been practiced in a large number of people at the academic societies. METHODS: Modified Socratic method was performed for the first time as an educational seminar using an example case of moderate acute cholecystitis based on the evidence described in Tokyo Guidelines 2018. We adopted a method that Takada had been modifying for many years: the instructor first knows the degree of recognition of the audience, then the instructor gives a lecture in an easy-to-understand manner and receives questions from the audience, followed by repeated questions and answers toward a common recognition. RESULTS: Using slides, video, and an answer pad, 281 participants including the audience, instructors and moderators came together to repeatedly ask and answer questions in the five sessions related to the case scenario. The recognition rate of the topic of Critical View of Safety increased significantly before vs after this method (53.0% vs 90.3%). The seminar had been successfully performed by receiving a lot of praise from the participants. CONCLUSION: This educational method is considered to be adopted by many academic societies in the future as an effective educational method.

Cholangio-venous reflux of biliary contents through paracellular pathways between hepatocytes in patients with acute cholangitis.

BACKGROUND: We re-analyzed data on cholangio-venous reflux from a clinical study conducted prospectively on 22 patients in 1974. METHOD: Direct cholangiography was performed with indocyanine green (ICG) mixed into UrographinR under monitoring of intrabiliary pressure, and the participants were allocated to three groups according to whether ICG leakage into the blood, signs of infection, or both, were present. RESULTS: The intrabiliary pressure of six patients negative for both ICG leakage and signs of infection was approximately 19.5 (median, [range 18-22]) cmH2 O. In contrast, for the five patients positive for ICG leakage but negative for signs of infection, the intrabiliary pressure was higher (median 32.0 [range 27-41) cmH2 O]. The 11 patients positive for both ICG leakage and signs of infection had the highest intrabiliary pressure (median 48.0 [range 33-77] cmH2 O). Our analyses revealed that, as the intrabiliary pressure increased, the status of ICG leakage and signs of infection appeared in a stepwise fashion. CONCLUSION: Our findings suggest that the tight junctions sealing the bile canaliculi deteriorated with increasing intrabiliary pressure, resulting in reflux of the biliary contents into the vascular system via paracellular pathways between hepatocytes.

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.

Learning curve and surgical factors influencing the surgical outcomes during the initial experience with laparoscopic pancreaticoduodenectomy.

BACKGROUND: Laparoscopic pancreaticoduodenectomy (LPD) requires sufficient laparoscopic training for optimal outcomes. Our aim is to determine the learning curve and investigate the factors influencing surgical outcomes during the learning curve. METHODS: We analyzed surgical results of 150 consecutive cases of LPD performed by three hepatopancreatobiliary surgeons during their 50 first cases. Learning curves were constructed by cumulative sum (CUSUM) analysis. Preoperative factors influencing resection time and blood loss were investigated in the introductory and stable periods. RESULTS : The learning curve could be divided into three phases: initial (1-20 cases), plateau (21-30), and stable (31-50). Resection time with lymph node dissection was significantly longer during the introductory period (initial and plateau periods) (P < 0.01) but not the stable phase (P = 0.51). Multivariate analysis revealed that patients with pancreatitis had longer resection times and massive blood loss in both the introductory and stable periods (stable phase). High visceral fat area was also significantly related to massive blood loss in the introductory period (P = 0.04). CONCLUSIONS: Hepatopancreatobiliary surgeons need more than 30 cases until LPD becomes stable. Lymph node dissection and patients with high visceral fat area and concomitant pancreatitis should be avoided during the introductory period of the learning curve.

Outcomes of 1,639 hepatectomies for non-colorectal non-neuroendocrine liver metastases: a multicenter analysis.

BACKGROUND: Whether non-colorectal non-neuroendocrine liver metastasis (NCNNLM) should be treated surgically remains unclear. METHODS: Data regarding 1,639 hepatectomies performed between 2001 and 2010 for 1,539 patients with NCNNLM were collected from 124 institutions. Patient characteristics, types of primary tumor, characteristics of liver metastases, and post-hepatectomy outcomes were analyzed. RESULTS: The five most frequent primary tumors were gastric carcinoma (540 patients [35%]), gastrointestinal stromal tumor (204 patients [13%]), biliary carcinoma (150 patients [10%]), ovarian cancer (107 patients [7%]), and pancreatic carcinoma (77 patients [5%]). R0/1 hepatectomy was achieved in 90% of patients, with 1.5% in-hospital mortality rate. Overall and disease-free survival rates of 1,465 patients included in survival analysis were 41% and 21%, respectively, at 5 years, and 28% and 15%, respectively, at 10 years. Five-year survival associated with the five frequent primary tumors were 32%, 72%, 17%, 52%, and 31%, respectively, and factors predictive of a poor outcome differed by the primary tumor type. CONCLUSIONS: Our data indicated that hepatectomy is safe for NCNNLM and that patient prognoses vary depending on the type of primary tumors. Indications for hepatectomy should be determined with reference to survival rates and risk factors specific to each of the various types of primary tumor.

Difficulty scoring system in laparoscopic distal pancreatectomy.

BACKGROUND: Several factors affect the level of difficulty of laparoscopic distal pancreatectomy (LDP). The purpose of this study was to develop a difficulty scoring (DS) system to quantify the degree of difficulty in LDP. METHODS: We collected clinical data for 80 patients who underwent LDP. A 10-level difficulty index was developed and subcategorized into a three-level difficulty index; 1-3 as low, 4-6 as intermediate, and 7-10 as high index. The automatic linear modeling (LINEAR) statistical tool was used to identify factors that significantly increase level of difficulty in LDP. RESULTS: The operator's 10-level DS concordance between the 10-level DS by the reviewers, LINEAR index DS, and clinical index DS systems were analyzed, and the weighted Cohen's kappa statistic were at 0.869, 0.729, and 0.648, respectively, showing good to excellent inter-rater agreement. We identified five factors significantly affecting level of difficulty in LDP; type of operation, resection line, proximity of tumor to major vessel, tumor extension to peripancreatic tissue, and left-sided portal hypertension/splenomegaly. CONCLUSIONS: This novel DS for LDP adequately quantified the degree of difficulty, and can be useful for selecting patients for LDP, in conjunction with fitness for surgery and prognosis.

Minimally invasive preservation versus splenectomy during distal pancreatectomy: a systematic review and meta-analysis.

BACKGROUND: Minimally invasive distal pancreatectomy (MIDP) has gained in popularity recently. However, there is no consensus on whether to preserve the spleen or not. In this study, we compared MIDP outcomes between spleen-preserving distal pancreatectomy (SPDP) and distal pancreatectomy with splenectomy (DPS); as well as outcomes between splenic vessel preservation (SVP) and Warshaw's technique (WT). METHODS: A systematic search of PubMed (MEDLINE) and Cochrane Library was conducted and the reference lists of review articles were hand-searched. RESULTS: Fifteen relevant studies with 769 patients were selected for meta-analyses of DPS and SPDP, while another 15 studies with 841 patients were used for the analysis between SVP and WT. Compared with the DPS group, SPDP patients had significantly lower incidences of infectious complications (P = 0.006) and pancreatic fistula (P = 0.002), shorter operative time (P < 0.001), and less blood loss (P = 0.01). Compared with WT, SVP patients had significantly lower incidences of splenic infarction (P < 0.001) and secondary splenectomy (P = 0.003). Subanalysis for laparoscopic surgery alone had similar results. CONCLUSIONS: Based on this study, SPDP has significantly superior outcomes compared to DPS. When a spleen is preserved, SVP has better outcomes over WT for reducing splenic complications.

Tokyo Guidelines 2018: initial management of acute biliary infection and flowchart for acute cholangitis.

The initial management of patients with suspected acute biliary infection starts with the measurement of vital signs to assess whether or not the situation is urgent. If the case is judged to be urgent, initial medical treatment should be started immediately including respiratory/circulatory management if required, without waiting for a definitive diagnosis. The patient's medical history is then taken; an abdominal examination is performed; blood tests, urinalysis, and diagnostic imaging are carried out; and a diagnosis is made using the diagnostic criteria for cholangitis/cholecystitis. Once the diagnosis has been confirmed, initial medical treatment should be started immediately, severity should be assessed according to the severity grading criteria for acute cholangitis/cholecystitis, and the patient's general status should be evaluated. For mild acute cholangitis, in most cases initial treatment including antibiotics is sufficient, and most patients do not require biliary drainage. However, biliary drainage should be considered if a patient does not respond to initial treatment. For moderate acute cholangitis, early endoscopic or percutaneous transhepatic biliary drainage is indicated. If the underlying etiology requires treatment, this should be provided after the patient's general condition has improved; endoscopic sphincterotomy and subsequent choledocholithotomy may be performed together with biliary drainage. For severe acute cholangitis, appropriate respiratory/circulatory management is required. Biliary drainage should be performed as soon as possible after the patient's general condition has been improved by initial treatment and respiratory/circulatory management. 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: flowchart for the management of acute cholecystitis.

We propose a new flowchart for the treatment of acute cholecystitis (AC) in the Tokyo Guidelines 2018 (TG18). Grade III AC was not indicated for straightforward laparoscopic cholecystectomy (Lap-C). Following analysis of subsequent clinical investigations and drawing on Big Data in particular, TG18 proposes that some Grade III AC can be treated by Lap-C when performed at advanced centers with specialized surgeons experienced in this procedure and for patients that satisfy certain strict criteria. For Grade I, TG18 recommends early Lap-C if the patients meet the criteria of Charlson comorbidity index (CCI) ≤5 and American Society of Anesthesiologists physical status classification (ASA-PS) ≤2. For Grade II AC, if patients meet the criteria of CCI ≤5 and ASA-PS ≤2, TG18 recommends early Lap-C performed by experienced surgeons; and if not, after medical treatment and/or gallbladder drainage, Lap-C would be indicated. TG18 proposes that Lap-C is indicated in Grade III patients with strict criteria. These are that the patients have favorable organ system failure, and negative predictive factors, who meet the criteria of CCI ≤3 and ASA-PS ≤2 and who are being treated at an advanced center (where experienced surgeons practice). If the patient is not considered suitable for early surgery, TG18 recommends early/urgent biliary drainage followed by delayed Lap-C once the patient's overall condition has improved. 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: 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.