Yamamoto, Masakazu

Objective: The aim of this study was to define robust benchmark values for the surgical treatment of perihilar cholangiocarcinomas (PHC) to enable unbiased comparisons. Background: Despite ongoing efforts, postoperative mortality and morbidity remains high after complex liver surgery for PHC. Benchmark data of best achievable results in surgical PHC treatment are however still lacking. Methods: This study analyzed consecutive patients undergoing major liver surgery for PHC in 24 high-volume centers in 3 continents over the recent 5-year period (2014–2018) with a minimum follow-up of 1 year in each patient. Benchmark patients were those operated at high-volume centers (≥50 cases during the study period) without the need for vascular reconstruction due to tumor invasion, or the presence of significant co-morbidities such as severe obesity (body mass index ≥35), diabetes, or cardiovascular diseases. Benchmark cutoff values were derived from the 75th or 25th percentile of the median values of all benchmark centers. Results: Seven hundred eight (39%) of a total of 1829 consecutive patients qualified as benchmark cases. Benchmark cut-offs included: R0 resection ≥57%, postoperative liver failure (International Study Group of Liver Surgery): ≤35%; in-hospital and 3-month mortality rates ≤8% and ≤13%, respectively; 3-month grade 3 complications and the CCI: ≤70% and ≤30.5, respectively; bile leak-rate: ≤47% and 5-year overall survival of ≥39.7%. Centers operating mostly on complex cases disclosed better outcome including lower post-operative liver failure rates (4% vs 13%; P = 0.002). Centers from Asia disclosed better outcomes. Conclusion: Surgery for PHC remains associated with high morbidity and mortality with now the availability of benchmark values covering 21 outcome parameters, which may serve as key references for comparison in any future analyses of individuals, group of patients or centers.

AbstractBackgroundHepatectomy 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.MethodsEight 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.ResultsThe 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.ConclusionsThese 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.

AbstractBackgroundLaparoscopic 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.MethodsWe 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).ConclusionsHepatopancreatobiliary 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.

AbstractBackgroundSeveral 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.MethodsWe 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.ResultsThe 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.ConclusionsThis 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.

AbstractBackgroundMinimally 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).MethodsA systematic search of PubMed (MEDLINE) and Cochrane Library was conducted and the reference lists of review articles were hand‐searched.ResultsFifteen 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.ConclusionsBased 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.

Abstract 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.

Abstract 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 ( TG 13), we proposed management bundles for acute cholangitis and cholecystitis. Here, in Tokyo Guidelines 2018 ( TG 18), we redefine the management bundles for acute cholangitis and cholecystitis. Critical parts of the bundles in TG 18 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 TG 18 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.

Abstract 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, TG 18 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, TG 18 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, TG 18 recommends early Lap‐C performed by experienced surgeons; and if not, after medical treatment and/or gallbladder drainage, Lap‐C would be indicated. TG 18 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, TG 18 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.

Abstract 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 ( TG 07) was revised in 2013. According to that revision, the TG 13 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 TG 13 diagnostic criteria of acute cholecystitis. On the other hand, the TG 13 severity grading for acute cholecystitis has been validated in numerous studies. As a result of these reviews, the TG 13 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, TG 13 diagnostic criteria and severity grading were judged from numerous validation studies as useful indicators in clinical practice and adopted as TG 18/ TG 13 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.

AbstractThe 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.