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.

Laparoscopic approach for port site mass diagnosed as a Schloffer tumor following surgery of ascending colon cancer.

Schloffer tumor is a foreign body granuloma that develops in the subcutaneous layer of the abdomen over several months to several years after surgery due to sutures. Here, we performed a laparoscopic resection for a benign Schloffer tumor that showed positive F-18 fluorodeoxyglucose (FDG) positron emission tomography (PET) at the port site of a laparoscopic right hemicolectomy for advanced colon cancer. We report a case in which systemic chemotherapy was avoided as a result of the histological examination following the laparoscopic approach. A 66-year-old female, who underwent laparoscopic right hemi colectomy for stage IIIA ascending colon cancer, was revealed an enhanced mass at the right side of the abdominal subcutaneous layer. PET examination showed a high accumulation of FDG. Laparoscopic tumor resection was performed. Pathological findings reported the formation identical to the Schloffer tumor. Schloffer tumor, which is rare, should be considered as one of the differential diagnoses for tumor with FDG-PET positivity at the port site during the postoperative surveillance period of colorectal cancer.

Short-term outcomes of pancreatoduodenectomy in older individuals over a 9-year period using real-world data: A multilevel analysis based on a nationwide administrative database in Japan.

BACKGROUND: We aimed to evaluate the short-term outcomes of pancreatoduodenectomy (PD) in older individuals. METHODS: Data from the Japanese Diagnosis Procedure Combination database on 62 275 patients who underwent PD from 1 April 2012 to 31 March 2020 were analyzed. Patients were divided into five age groups: <70, 70-74, 75-79, 80-84, and ≥85 years. The associations between postoperative outcomes and age were investigated using multilevel analysis. The mean differences in length of hospital stay and cost were also compared. RESULTS: The rate of PD in older individuals increased annually. Compared with the youngest age group (< 70 years), the incidence rate ratios for in-hospital mortality were 1.52 (95% confidence interval [CI]: 1.30-1.76), 2.07 (1.82-2.37), 2.29 (1.94-2.71), and 2.92 (2.20-3.87) in the 70-74, 75-79, 80-84, and ≥ 85-year-old age groups, respectively (all p < .001). Postoperative complications, length of postoperative hospital stay, and cost increased significantly with increasing age. CONCLUSIONS: These real-world data emphasize the higher levels of morbidity, mortality, and cost in older patients. Careful attention should be paid when considering the indication for PD in older individuals.

Impact of AI system on recognition for anatomical landmarks related to reducing bile duct injury during laparoscopic cholecystectomy.

BACKGROUND: According to the National Clinical Database of Japan, the incidence of bile duct injury (BDI) during laparoscopic cholecystectomy has hovered around 0.4% for the last 10 years and has not declined. On the other hand, it has been found that about 60% of BDI occurrences are due to misidentifying anatomical landmarks. However, the authors developed an artificial intelligence (AI) system that gave intraoperative data to recognize the extrahepatic bile duct (EHBD), cystic duct (CD), inferior border of liver S4 (S4), and Rouviere sulcus (RS). The purpose of this research was to evaluate how the AI system affects landmark identification. METHODS: We prepared a 20-s intraoperative video before the serosal incision of Calot's triangle dissection and created a short video with landmarks overwritten by AI. The landmarks were defined as landmark (LM)-EHBD, LM-CD, LM-RS, and LM-S4. Four beginners and four experts were recruited as subjects. After viewing a 20-s intraoperative video, subjects annotated the LM-EHBD and LM-CD. Then, a short video is shown with the AI overwriting landmark instructions; if there is a change in each perspective, the annotation is changed. The subjects answered a three-point scale questionnaire to clarify whether the AI teaching data advanced their confidence in verifying the LM-RS and LM-S4. Four external evaluation committee members investigated the clinical importance. RESULTS: In 43 of 160 (26.9%) images, the subjects transformed their annotations. Annotation changes were primarily observed in the gallbladder line of the LM-EHBD and LM-CD, and 70% of these shifts were considered safer changes. The AI-based teaching data encouraged both beginners and experts to affirm the LM-RS and LM-S4. CONCLUSION: The AI system provided significant awareness to beginners and experts and prompted them to identify anatomical landmarks linked to reducing BDI.

Changes in operative trends and short-term outcomes of surgery for congenital biliary dilatation in adults using real-world data: A multilevel analysis based on a nationwide administrative database in Japan.

Aim: We aimed to evaluate the operative trends and compare the short-term outcomes between open and laparoscopic surgery for congenital biliary dilatation (CBD) in adults using real-world data from Japan. Methods: Data from the Japanese Diagnosis Procedure Combination database on 941 patients undergoing surgery for CBD at 357 hospitals from April 1, 2016, to March 31, 2021, were analyzed. The patients were divided into two groups: open surgery (n = 764) and laparoscopic surgery (n = 177). We performed a retrospective analysis via a multilevel analysis of the short-term surgical outcomes and costs between open and laparoscopic surgery. Results: The rate of laparoscopic surgery has been increasing annually and had almost doubled to 25% by 2021. There were no significant differences in the in-hospital mortality rate or postoperative morbidity between the two groups. The length of anesthesia was significantly longer in the laparoscopic than open surgery group (8.80 vs 6.16 hours, p < .001). The time to removal of the abdominal drain and length of hospital stay were significantly shorter in the laparoscopic than open surgery group (6.12 vs 8.35 days, p = .001 and 13.57 vs 15.79 days, p < .001, respectively). The coefficient for cost was 463 235 yen (95% confidence interval, 289 679-636 792) higher in laparoscopic than open surgery (p < .001). Conclusion: The short-term results were comparable between laparoscopic and open surgery for CBD. Further investigation is needed to validate our findings and long-term outcomes.

MR Prediction of Malignant Switch With the Cyst Fluid's T2 Value in Intraductal Papillary Mucinous Neoplasm of the Pancreas: A Preliminary Study.

BACKGROUND/AIM: We investigated whether the malignant switch of intraductal papillary mucinous neoplasm (IPMN) of the pancreas can be predicted by using the T1ϱ, T2, and apparent diffusion coefficient (ADC) values of cyst fluid. PATIENTS AND METHODS: We retrospectively analyzed the magnetic resonance (MR) images of 60 patients (26 males, 34 females, mean age 61 years) with branch-duct type and mixed-type IPMNs. The IPMNs were diagnosed clinically in 39 patients and histologically in 21 patients. The malignant potential was classified by MR imaging based on the international consensus guidelines for the management of IPMN established in 2017. Morphologically, 42 patients had "worrisome features" and three had "high-risk stigmata." Histologically, 14 lesions were diagnosed as low-grade dysplasia and seven as intermediate-grade dysplasia. The T1ϱ, T2, and ADC values of cyst fluid in each patient's largest cyst were measured on the same slice, avoiding solid components. Spearman's rank correlation test was used to determine the correlation between the morphological malignancy and the T1ϱ, T2, and ADC values. These values were also compared between the low-grade and intermediate-grade groups by Mann-Whitney U-test. RESULTS: There was a significant rank-correlation between the morphological classification and T2 value (p=0.04). The T2 value of the intermediate-grade group was significantly higher than that of the low-grade group (p=0.03). No significant correlations were morphologically or histologically obtained regarding T1ϱ and ADC. CONCLUSION: The T2 value of cyst fluid together with other MR-signs may be useful for predicting the malignant switch in IPMN of the pancreas.

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.

Evaluation of cholecystectomy in older individuals using real-world data: a multilevel analysis based on a nationwide administrative database in Japan.

BACKGROUND: In the present study, we aimed to evaluate the clinical outcomes of cholecystectomy in older individuals. METHODS: In this retrospective study, data from the Japanese Diagnosis Procedure Combination database on 96,620 patients who had undergone cholecystectomy at 1060 hospitals from 2018 to 2020 were analyzed. Patients were divided into five age groups: < 75, 75-79, 80-84, 85-89, and ≥ 90 years. Associations between postoperative outcomes and age group were investigated by logistic regression analysis. Mean differences between age groups in time to postoperative recovery and cost were also compared. RESULTS: Older patients had higher rates of poor scores for activities of daily living and preoperative comorbidity. Compared with the youngest age group (< 75 years), the odds ratios for in-hospital mortality were 3.00 (95% confidence interval, 1.74-5.19), 7.54 (4.73-12.01), 13.47 (8.21-22.14), and 27.64 (15.56-49.09), in the 75-79, 80-84, 85-89, and ≥ 90-year-old age group, respectively (all p < 0.001). Furthermore, the length of postoperative hospital stay and rates of postoperative complications, postoperative reintubation, and reoperation with general anesthesia increased significantly in parallel with increasing age, the highest rates being in the ≥ 90 year-old age group. CONCLUSIONS: Our real-world data highlight the worse postoperative outcomes, including a higher mortality rate, in older patients undergoing cholecystectomy. Care should be taken when considering the indications for surgery in such patients.

Extensive (subtotal) distal pancreatectomy for pancreatic ductal adenocarcinoma: a propensity score matched cohort study of short- and long-term outcomes compared with those of conventional distal pancreatectomy.

PURPOSE: Extensive distal pancreatectomy (ExDP) can transect the pancreatic parenchyma more from the right side than conventional distal pancreatectomy (CDP) can. This study aimed to evaluate the short- and long-term outcomes of ExDP for pancreatic ductal adenocarcinoma (PDAC) of the pancreatic body, located adjacent to the portal vein (PV). METHODS: Medical records of 98 patients who underwent ExDP (n = 15) or CDP (n = 83) for PDAC were retrospectively reviewed. Short- and long-term outcomes of the two groups were compared. Propensity score matched analysis was additionally performed to minimize the impact of treatment allocation bias. RESULTS: In the total cohort, the CDP group had a significantly higher proportion of pancreatic tail lesions (P < 0.01), higher proportion of males, and larger tumor size. Of the 15 patients who underwent ExDP, 11 could be matched. These differences of patients' characteristics were not observed after matching. Before and after matching, the duration of surgery, blood loss, rate of morbidity including pancreatic fistula, and postoperative course were comparable between the groups. The rate of recurrence and recurrence pattern were also not significantly different between the groups. ExDP for PDAC of the pancreatic body near the PV did not increase local or lymph node recurrence. The disease-free and overall survival did not differ between the groups. CONCLUSIONS: Surgical and oncological outcomes after ExDP for PDAC were acceptable and comparable to those after CDP. ExDP is a feasible procedure, and could be an option for the treatment of PDAC of the pancreatic body near PV.

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.

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.

Efficacy of Distal Pancreatectomy Combined With Modified DuVal Procedure in Patients With a High Risk of Postoperative Pancreatic Fistula.

BACKGROUND: The incidence of postoperative pancreatic fistula (POPF) after distal pancreatectomy (DP) remains high. The present study aimed to clarify the efficacy of our modified DuVal (mDuVal) pancreatojejunostomy following DP in patients with a high risk of POPF. METHODS: The medical records of 346 consecutive patients who underwent DP between 2006 and 2016 were retrospectively reviewed. Perioperative features were compared between 24 patients undergoing mDuVal (mDuVal group) and 322 patients undergoing standard DP (standard DP group). RESULTS: Preoperative American Society of Anesthesiologists physical status 1 was more frequent in the standard group than in the mDuVal group (P = .02). The start of a solid diet after operation was significantly earlier in the mDuVal group than in the standard DP group (P = .01), while there were no significant differences between the groups for clinically relevant POPF, amylase concentration in the drainage fluid on postoperative day 1 and days 3-5, time to drain removal, additional intervention for POPF, overall complications, or postoperative hospital stay. DISCUSSION: The mDuVal procedure could be an option for patients with a high risk of POPF to improve the outcomes after DP. Further investigation involving large study populations is necessary to clarify the efficacy of this procedure.

Glissonean approach for hepatic inflow control in minimally invasive anatomic liver resection: A systematic review.

BACKGROUND: The Glissonean approach has been widely validated for both open and minimally invasive anatomic liver resection (MIALR). However, the possible advantages compared to the conventional hilar approach are still under debate. The aim of this systematic review was to evaluate the application of the Glissonean approach in MIALR. METHODS: A systematic review of the literature was conducted on PubMed and Ichushi databases. Articles written in English or Japanese were included. From 2,390 English manuscripts evaluated by title and abstract, 43 were included. Additionally, 23 out of 463 Japanese manuscripts were selected. Duplicates were removed, including the most recent manuscript. RESULTS: The Glissonean approach is reported for both major and minor MIALR. The 1st, 2nd and 3rd order divisions of both right and left portal pedicles can be reached following defined anatomical landmarks. Compared to the conventional hilar approach, the Glissonean approach is associated with shorter operative time, lower blood loss, and better peri-operative outcomes. CONCLUSIONS: Glissonean approach is safe and feasible for MIALR with several reported advantages compared to the conventional hilar approach. Clear knowledge of Laennec's capsule anatomy is necessary and serves as a guide for the dissection. However, the best surgical approach to be performed depends on surgeon experience and patients' characteristics. Standardization of the Glissonean approach for MIALR is important.

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.

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.

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.

Evaluation of relationship between splenic artery and pancreatic parenchyma using three-dimensional computed tomography for laparoscopic distal pancreatectomy.

AIM: Isolating the root of the splenic artery (SPA) is a challenging procedure in laparoscopic distal pancreatectomy (LDP). We investigated the usefulness of evaluation of the relationship between the SPA and pancreatic parenchyma using three-dimensional computed tomography (3D-CT). METHODS: In total, 104 patients were evaluated. The relationship between the SPA and pancreatic parenchyma was classified into two types: buried and non-buried. Video clips of 50 patients who underwent LDP requiring isolation of the SPA root were reviewed to determine whether the classification is related to difficulty of LDP. RESULTS: Of the 50 assessed patients who underwent LDP, the relationship between the SPA and pancreatic parenchyma was the buried type in 30 (60.0%) and non-buried type in 20 (40.0%). The buried type was associated with a significantly longer median operative time than the non-buried type (285.0 vs. 235.5 min, respectively; P < 0.01). The median time required to isolate the SPA in the buried type (25.8 min; range, 4.0-101 min) was significantly longer than that in the non-buried type (7.0 min; range, 1.0-27.0 min) (P < 0.001). CONCLUSION: Preoperative 3D-CT around the pancreas is practical for predicting the difficulty of SPA isolation and determining the safety of the procedure.

Management of postoperative pancreatic fistula after pancreatoduodenectomy: Analysis of 600 cases of pancreatoduodenectomy patients over a 10-year period at a single institution.

BACKGROUND: Although postoperative pancreatic fistula (POPF) is a common and critical complication of pancreatoduodenectomy (PD), effective strategies to prevent POPF have not yet been completely developed. Because appropriate management of POPF is important to reduce the mortality rate after PD, in this study we aimed to evaluate our approach for the management of POPF after PD, including the postoperative course. METHODS: This retrospective study included 605 consecutive patients who underwent PD at our hospital between 2010 and 2020. All patients who developed POPF were first managed conservatively, with drainage tubes placed during surgery retained to manage POPF. In cases wherein conservative treatment was unsuccessful, open drainage, followed by continuous negative pressure and continuous irrigation, was used. For open drainage, the surgical wound was opened bluntly (approximate length, 5 cm) under local anesthesia, and the fluid was directly and completely drained. RESULTS: The prevalence of POPF of grades B and C was 15.4% (n = 93) and 0.33% (n = 2), respectively. Of these patients, 1 required reoperation, 43 recovered with conservative management only, 47 required open drainage, and 4 required image-guided percutaneous drainage. Postoperative hemorrhage with a pseudoaneurysm was identified in 3 (0.66%) patients. The postoperative in-hospital mortality rate was low (n = 1, 0.16%). The rate of successful POPF management was 98.9%. CONCLUSION: Based on our high success rate in POPF management, we consider open drainage to be a safe primary management method for POPF.

FoundationOne® CDx gene profiling in Japanese pancreatic ductal adenocarcinoma patients: a single-institution experience.

PURPOSE: The aim of this study was to investigate the genetic mutation profiles of Japanese pancreatic ductal adenocarcinoma (PDAC) patients. METHODS: Next-generation sequencing was performed using FoundationOne® CDx on 17 PDAC patients who were treated by surgical resection at Kyushu University Hospital between February 2016 and January 2019. The tumor mutational burden and microsatellite instability status were also assessed. RESULTS: There were 16 patients (94%) with KRAS mutations, 13 (76%) with TP53 mutations, three (18%) with SMAD4 mutations, and one (6%) with a CDKN2A mutation. All patients had at least one pathogenic variant or a likely pathogenic variant. No patient had targeted therapies that matched with any clinical benefit according to FoundationOne® CDx. An unresectable PDAC patient with BRCA2-mutant disease was successfully treated by conversion surgery using platinum-based neoadjuvant chemotherapy. CONCLUSIONS: Currently, FoundationOne® CDx might be difficult to use on PDAC patients, although further investigations with larger study populations are called for.

Clinical significance of postoperative acute pancreatitis after pancreatoduodenectomy and distal pancreatectomy.

BACKGROUND: The definition of postoperative acute pancreatitis as a specific complication of pancreatic surgery was proposed in 2016. Its presence and relevance have not been established, especially after a distal pancreatectomy. METHODS: Medical records of 319 patients who underwent pancreatoduodenectomy or distal pancreatectomy were analyzed. Postoperative acute pancreatitis was defined as an increase in serum amylase activity greater than the upper normal limit on postoperative day 1, according to Connor's definition of postoperative acute pancreatitis. RESULTS: Postoperative acute pancreatitis occurred in 63.4% of 153 of the patients undergoing pancreatoduodenectomy and 65.7% of the 166 undergoing distal pancreatectomies. Patients who developed postoperative acute pancreatitis after pancreatoduodenectomy experienced an increase in the rate of morbidity (22.7% vs 7.1%; P = .0137), including postoperative pancreatic fistula (18.6% vs 1.8%; P = .024), resulting in greater postoperative stays (21 days vs 17 days; P = .0008). Postoperative acute pancreatitis in association with an increased serum C-reactive protein ≥18.0 mg/dL (which we defined as a clinically relevant postoperative acute pancreatitis) more strongly indicated the occurrence of severe complications (P = .0032) and was an independent predictor of postoperative pancreatic fistula after pancreatoduodenectomy (odds ratio, 3.03; P = .0448). Patients who developed postoperative acute pancreatitis after distal pancreatectomy experienced similar postoperative courses regarding morbidity and the duration of postoperative stay. CONCLUSION: The clinical relevance of postoperative acute pancreatitis differs after a pancreatoduodenectomy versus a distal pancreatectomy. The development of effective strategies for preventing postoperative acute pancreatitis might improve surgical outcomes after pancreatoduodenectomy.