Defining Global Benchmarks for Laparoscopic Right Posterior Sectionectomy/H67: An International Multicenter Study.

OBJECTIVE: We aimed to establish global benchmark outcomes indicators for L-RPS/H67. BACKGROUND: Minimally invasive liver resections has seen an increase in uptake in recent years. Over time, challenging procedures as laparoscopic right posterior sectionectomies (L-RPS)/H67 are also increasingly adopted. METHODS: This is a post hoc analysis of a multicenter database of 854 patients undergoing minimally invasive RPS (MI-RPS) in 57 international centers in 4 continents between 2015 and 2021. There were 651 pure L-RPS and 160 robotic RPS (R-RPS). Sixteen outcome indicators of low-risk L-RPS cases were selected to establish benchmark cutoffs. The 75th percentile of individual center medians for a given outcome indicator was set as the benchmark cutoff. RESULTS: There were 573 L-RPS/H67 performed in 43 expert centers, of which 254 L-RPS/H67 (44.3%) cases qualified as low risk benchmark cases. The benchmark outcomes established for operation time, open conversion rate, blood loss ≥500 mL, blood transfusion rate, postoperative morbidity, major morbidity, 90-day mortality and textbook outcome after L-RPS were 350.8 minutes, 12.5%, 53.8%, 22.9%, 23.8%, 2.8%, 0% and 4% respectively. CONCLUSIONS: The present study established the first global benchmark values for L-RPS/H6/7. The benchmark provided an up-to-date reference of best achievable outcomes for surgical auditing and benchmarking.

Liver Resection Under Total Hepatic Vascular Exclusion with In Situ Hypothermic Isolated Hepatic Perfusion for Advanced Liver Tumors.

PURPOSE: Continuous dissection or simultaneous reconstruction of the hepatic vein (HV) and inferior vena cava (IVC) was achieved under total hepatic vascular exclusion (THVE) with in situ hypothermic isolated hepatic perfusion (HIHP) in two cases. CASE 1: The patient previously underwent liver resections with the right HV for colorectal liver metastasis (CRLM). This time, the CRLM had invaded the left HV and IVC, and five courses of FOLFILI plus ramucirumab were given, resulting in stable disease. Due to expected high HV pressure, liver parenchymal transection was started under THVE. Sub-segmentectomy with patch graft plasty of the IVC and reconstruction of the left HV using a jugular vein graft were performed under THVE and HIHP. This patient died at home 3 months after surgery; the cause of death was unknown. CASE 2: Hepatocellular carcinoma in the caudate lobe was in extensive contact with the roots of three main HVs and the IVC, and pressed the hepatocaval confluence, with high HV pressure expected. In addition, tumor thrombosis extended to both the main portal vein and the common bile duct, resulting in the inability to introduce chemotherapy. After tumor thrombectomy, liver parenchymal transection was started under THVE. Extended left hepatectomy with wedge resection, and primary suture of the right HV and IVC was performed under THVE and HIHP. Recurrence-free and overall survivals were 8 months (lung metastasis) and 31 months, respectively. CONCLUSIONS: In liver resection for liver tumors located in the hepatocaval confluence, THVE with HIHP is useful for ensuring the safety.

Impact of Liver Cirrhosis, Severity of Cirrhosis, and Portal Hypertension on the Difficulty and Outcomes of Laparoscopic and Robotic Major Liver Resections for Primary Liver Malignancies.

BACKGROUND: Minimally invasive liver resections (MILR) offer potential benefits such as reduced blood loss and morbidity compared with open liver resections. Several studies have suggested that the impact of cirrhosis differs according to the extent and complexity of resection. Our aim was to investigate the impact of cirrhosis on the difficulty and outcomes of MILR, focusing on major hepatectomies. METHODS: A total of 2534 patients undergoing minimally invasive major hepatectomies (MIMH) for primary malignancies across 58 centers worldwide were retrospectively reviewed. Propensity score (PSM) and coarsened exact matching (CEM) were used to compare patients with and without cirrhosis. RESULTS: A total of 1353 patients (53%) had no cirrhosis, 1065 (42%) had Child-Pugh A and 116 (4%) had Child-Pugh B cirrhosis. Matched comparison between non-cirrhotics vs Child-Pugh A cirrhosis demonstrated comparable blood loss. However, after PSM, postoperative morbidity and length of hospitalization was significantly greater in Child-Pugh A cirrhosis, but these were not statistically significant with CEM. Comparison between Child-Pugh A and Child-Pugh B cirrhosis demonstrated the latter had significantly higher transfusion rates and longer hospitalization after PSM, but not after CEM. Comparison of patients with cirrhosis of all grades with and without portal hypertension demonstrated no significant difference in all major perioperative outcomes after PSM and CEM. CONCLUSIONS: The presence and severity of cirrhosis affected the difficulty and impacted the outcomes of MIMH, resulting in higher blood transfusion rates, increased postoperative morbidity, and longer hospitalization in patients with more advanced cirrhosis. As such, future difficulty scoring systems for MIMH should incorporate liver cirrhosis and its severity as variables.

Explainable artificial intelligence prediction-based model in laparoscopic liver surgery for segments 7 and 8: an international multicenter study.

BACKGROUND: Artificial intelligence (AI) is becoming more useful as a decision-making and outcomes predictor tool. We have developed AI models to predict surgical complexity and the postoperative course in laparoscopic liver surgery for segments 7 and 8. METHODS: We included patients with lesions located in segments 7 and 8 operated by minimally invasive liver surgery from an international multi-institutional database. We have employed AI models to predict surgical complexity and postoperative outcomes. Furthermore, we have applied SHapley Additive exPlanations (SHAP) to make the AI models interpretable. Finally, we analyzed the surgeries not converted to open versus those converted to open. RESULTS: Overall, 585 patients and 22 variables were included. Multi-layer Perceptron (MLP) showed the highest performance for predicting surgery complexity and Random Forest (RF) for predicting postoperative outcomes. SHAP detected that MLP and RF gave the highest relevance to the variables "resection type" and "largest tumor size" for predicting surgery complexity and postoperative outcomes. In addition, we explored between surgeries converted to open and non-converted, finding statistically significant differences in the variables "tumor location," "blood loss," "complications," and "operation time." CONCLUSION: We have observed how the application of SHAP allows us to understand the predictions of AI models in surgical complexity and the postoperative outcomes of laparoscopic liver surgery in segments 7 and 8.

Defining Global Benchmarks for Laparoscopic Liver Resections: An International Multicenter Study.

OBJECTIVE: To establish global benchmark outcomes indicators after laparoscopic liver resections (L-LR). BACKGROUND: There is limited published data to date on the best achievable outcomes after L-LR. METHODS: This is a post hoc analysis of a multicenter database of 11,983 patients undergoing L-LR in 45 international centers in 4 continents between 2015 and 2020. Three specific procedures: left lateral sectionectomy (LLS), left hepatectomy (LH), and right hepatectomy (RH) were selected to represent the 3 difficulty levels of L-LR. Fifteen outcome indicators were selected to establish benchmark cutoffs. RESULTS: There were 3519 L-LR (LLS, LH, RH) of which 1258 L-LR (40.6%) cases performed in 34 benchmark expert centers qualified as low-risk benchmark cases. These included 659 LLS (52.4%), 306 LH (24.3%), and 293 RH (23.3%). The benchmark outcomes established for operation time, open conversion rate, blood loss ≥500 mL, blood transfusion rate, postoperative morbidity, major morbidity, and 90-day mortality after LLS, LH, and RH were 209.5, 302, and 426 minutes; 2.1%, 13.4%, and 13.0%; 3.2%, 20%, and 47.1%; 0%, 7.1%, and 10.5%; 11.1%, 20%, and 50%; 0%, 7.1%, and 20%; and 0%, 0%, and 0%, respectively. CONCLUSIONS: This study established the first global benchmark outcomes for L-LR in a large-scale international patient cohort. It provides an up-to-date reference regarding the "best achievable" results for L-LR for which centers adopting L-LR can use as a comparison to enable an objective assessment of performance gaps and learning curves.

Impact of Tumor Size on the Difficulty of Laparoscopic Major Hepatectomies: An International Multicenter Study.

INTRODUCTION: Although tumor size (TS) is known to affect surgical outcomes in laparoscopic liver resection (LLR), its impact on laparoscopic major hepatectomy (L-MH) is not well studied. The objectives of this study were to investigate the impact of TS on the perioperative outcomes of L-MH and to elucidate the optimal TS cutoff for stratifying the difficulty of L-MH. METHODS: This was a post-hoc analysis of 3008 patients who underwent L-MH at 48 international centers. A total 1396 patients met study criteria and were included. The impact of TS cutoffs was investigated by stratifying TS at each 10-mm interval. The optimal cutoffs were determined taking into consideration the number of endpoints which showed a statistically significant split around the cut-points of interest and the magnitude of relative risk after correction for multiple risk factors. RESULTS: We identified 2 optimal TS cutoffs, 50 mm and 100 mm, which segregated L-MH into 3 groups. An increasing TS across these 3 groups (≤ 50 mm, 51-100 mm, > 100 mm), was significantly associated with a higher open conversion rate (11.2%, 14.7%, 23.0%, P < 0.001), longer operating time (median, 340 min, 346 min, 365 min, P = 0.025), increased blood loss (median, 300 ml,  ml, 400 ml, P = 0.002) and higher rate of intraoperative blood transfusion (13.1%, 15.9%, 27.6%, P < 0.001). Postoperative outcomes such as overall morbidity, major morbidity, and length of stay were comparable across the three groups. CONCLUSION: Increasing TS was associated with poorer intraoperative but not postoperative outcomes after L-MH. We determined 2 TS cutoffs (50 mm and 10 mm) which could optimally stratify the surgical difficulty of L-MH.

Laparoscopic Left Hepatectomy with Resection of the Spiegel Lobe Using the Modified Caudate Lobe-First Approach.

BACKGROUND: Laparoscopic left hepatectomy with resection of the Spiegel lobe remains a technically demanding procedure as it is a deep-seated area surrounding the inferior vena cava (IVC). Mobilization of the Spiegel lobe requires safe exposure of the ventral side of the IVC while dissecting the short hepatic veins from the IVC. Additionally, wide space is needed to isolate the left Glissonean pedicle (Glt). We used a modified caudate lobe-first approach to overcome this challenge Maeda (J Hepato-Bil Pancreat Sci 25:335-41, 2018), Li (J Gastrointest Surg 23:1084-5, 2019), Homma (Surg Endosc 33:3851-7, 2019). METHODS: The ischemic area was confirmed after isolating the left and middle hepatic artery and left portal vein. After mobilizing the left lateral section, the Spiegel lobe was divided from the notch, which is the boundary between the caudate lobe and the Spiegel lobe, toward the middle hepatic vein (MHV). The Spiegel lobe was safely detached from the IVC with a short hepatic vein transected with the caudo-dorsal view. The Glt could be easily isolated due to the wide space on the ventral side of the IVC. After dividing the left hepatic duct, the MHV was exposed continuously from the root to the periphery, and parenchymal transection was completed by connecting the demarcation line and MHV. RESULTS: The total operation time was 430 min, and estimated blood loss was minimal. The patient was discharged on postoperative day 6 without complications. CONCLUSIONS: The modified caudate lobe-first approach can be used to safely perform laparoscopic left hepatectomy combined with the Spiegel lobe resection.

Laparoscopic Anatomic Liver Resection of the Dorsal Part of Segment 8 Using an Hepatic Vein-Guided Approach.

BACKGROUND: Laparoscopic anatomic liver resection is considered highly challenging, especially in segment 8 (S8), owing to the limited angle of the laparoscope and limited manipulation of the surgical instrument1,2. Additionally, resection is technically difficult when approaching the more peripheral branches since the Glissonean pedicle of S8 has several variations3 and is far from the hepatic hilum. The hepatic vein (HV)-guided approach involves entering from the cranial side of the liver while overcoming these difficulties with the unique view and techniques of laparoscopy4,5. We describe laparoscopic anatomic resection of the dorsal part of S8 using the HV-guided approach for hepatocellular carcinoma. METHODS: The drainage vein of segment 8 (V8), which often runs between the ventral and dorsal parts of S86,7, was exposed from the confluence of the middle HV to the periphery. The dorsal Glissonean branch of S8 (G8dor) was identified by deep dissection of the parenchyma on the right side of the V8. The right HV (RHV) was exposed toward the periphery after dissecting the G8dor. Liver parenchymal dissection was completed by connecting the demarcation line and the RHV. RESULTS: The total operation time was 319 min, estimated blood loss was 5 mL, and the patient was discharged on postoperative day 6 with no complications. CONCLUSION: Laparoscopic anatomic resection of the dorsal parts of S8 could be safely performed by exposing the HVs from their roots and using the HVs as a landmark to identify the intrahepatic Glissonean pedicles.

Intrahepatic Glissonean Approach for Laparoscopic Bisegmentectomy 7 and 8 With Root-Side Hepatic Vein Exposure.

BACKGROUND: Laparoscopic anatomic liver resections of the posterosuperior segments are technically demanding procedures.1-5 The segments are located in a deep-seated area of the liver surrounded by the ribs and the diaphragm, making forceps manipulation difficult. To overcome this limitation, an intrahepatic Glissonean approach and exposure of the hepatic veins from the root side was applied.6-10 The authors describe the technical aspects of performing a bisegmentectomy 7-8. METHODS: Liver parenchymal transection was initiated from the ventral aspect of the root of the middle hepatic vein, which often runs in the intersegmental plane, identifying the Glissonean pedicle of segment 8 (G8). After dissection of the G8, segmentectomy 8 was performed through identification of the ischemic area. After complete mobilization of the right lobe, the Glissonean pedicle of segment 7 (G7), which runs relatively near the liver surface,9, 10 was marked using ultrasonography. After division of the G7, a wide dissection between the caudate lobe and segment 7 was performed and connected to the previously dissected plane from the dorsal side of the right hepatic vein (RHV). Finally, bisegmentectomy 7-8 was performed with RHV resection because of tumor invasion. RESULTS: The operation time was 510 min, and the estimated blood loss was 150 ml. The patient was discharged on postoperative day 10 without any complications. CONCLUSIONS: Application of the intrahepatic Glissonean approach and exposure of the major hepatic veins from their roots using unique laparoscopic principles allows a safe performance of bisegmentectomy 7-8.

Outcomes and management of delayed complication after severe blunt liver injury.

BACKGROUND: The treatment of delayed complications after liver trauma such as bile leakage (BL) and hepatic artery pseudoaneurysms (HAPs) is difficult. The purpose of this study is to investigate the outcomes and management of post-traumatic BL and HAPs. METHODS: We retrospectively evaluated patients diagnosed with blunt liver injury, graded by the American Association for the Surgery of Trauma Liver Injury Scale, who were admitted to our hospital between April 2010 and December 2019. Patient characteristics and treatments were analyzed. RESULTS: A total of 176 patients with blunt liver injury were evaluated. Patients were diagnosed with grade I-II liver injury (n = 127) and with grade III-V injury (n = 49). BL was not observed in patients with grade I-II injury. Eight patients with grade III-V injury developed BL: surgical intervention was not needed for six patients with peripheral bile duct injury, but hepaticojejunostomy was needed for two patients with central bile duct injury. Out of 10 patients with HAPs, only three with grade I-II injury and one with grade III-V were treated conservatively; the rest six with grade III-V injury required transcatheter arterial embolization (TAE). All pseudoaneurysms disappeared. CONCLUSIONS: Severe blunt liver injury causing peripheral bile duct injury can be treated conservatively. In contrast, the central bile duct injury requires surgical treatment. HAPs with grade I-II injury might disappear spontaneously. HAPs with grade III-V injury should be considered TAE.

Short-term outcomes of laparoscopic versus open liver resection for hepatocellular carcinoma in older patients: a propensity score matching analysis.

BACKGROUND: The incidence of hepatocellular carcinoma (HCC) requiring surgical treatment in older patients has been continuously increasing. This study aimed to examine the safety and feasibility of performing laparoscopic liver resection (LLR) versus open liver resection (OLR) for HCC in older patients at a Japanese institution. METHODS: Between January 2010 and June 2021, 133 and 145 older patients (aged ≥ 70 years) who were diagnosed with HCC underwent LLR and OLR, respectively. Propensity score matching (PSM) analysis with covariates of baseline characteristics was performed. The intraoperative and postoperative data were evaluated in both groups. RESULTS: After PSM, 75 patients each for LLR and OLR were selected and the data compared. No significant differences in demographic characteristics, clinical data, and operative times were observed between the groups, although less than 10% of cases in each group underwent a major resection. Blood loss (OLR: 370 mL, LLR: 50 mL; P < 0.001) was lower, and the length of postoperative hospital stay (OLR: 12 days, LLR: 7 days; P < 0.001) and time to start of oral intake (OLR: 2 days, LLR: 1 day; P < 0.001) were shorter in the LLR group than in the OLR group. The incidence of complications ≥ Clavien-Dindo class IIIa was similar between the two groups. CONCLUSIONS: LLR, especially minor resections, is safely performed and feasible for selected older patients with HCC.

How-I-do-it: laparoscopic left medial sectionectomy utilizing a cranial approach to the middle hepatic vein and Laennec's capsule.

BACKGROUND: Laparoscopic anatomic liver resection is technically demanding, given the need to safely isolate the Glissonean pedicles and expose the hepatic veins (HVs) on the liver parenchyma cut surface. Laennec's capsule is observed around the Glissonean pedicles and root of the HVs. However, its existence, particularly on the peripheral side of the HVs, remains controversial. Herein, we describe Laennec's capsule-related histopathological findings around the HVs and a safe laparoscopic left medial sectionectomy utilizing Laennec's capsule. METHODS: The extrahepatic Glissonean approach was performed by connecting Gates II and III, in accordance with Sugioka's Gate theory. Liver parenchymal transection commenced along the demarcation line, which is between the medial and lateral sections, and the G4 was dissected during transection. Subsequently, via the outer-Laennec approach, the middle hepatic vein (MHV) was exposed from the root side in cranial view, while Laennec's capsule was preserved. Parenchymal transection was completed while connecting the MHV with the demarcation line. We obtained the membrane surrounding the HVs and performed histopathological examinations. RESULTS: Six patients underwent laparoscopic left medial sectionectomy from February 2012 to November 2020. There were no cases involving complications (Clavien-Dindo classification; grade II or higher), open-surgery conversion, transfusion, or surgery-related death. The histopathological findings showed Laennec's capsule surrounding both the trunk of the major HVs and the peripheral side of the HVs. CONCLUSIONS: A cranial approach to the major HVs utilizing Laennec's capsule is a feasible and advantageous procedure for laparoscopic left medial sectionectomy. We propose that Laennec's capsule surrounds the entire length of the HVs.

[Case of Gastric Malignant Lymphoma Invading Other Organs with Bleeding Treated by Surgery].

A female in her late 50s experienced dyspnea and was transported by an ambulance. Her hemoglobin score was low, and CT imaging showed a giant tumor in her stomach. The tumor perforated her liver and invaded the abdominal wall and duodenum around the Treitz ligament. She required surgery because of the massive hemorrhage due to the tumor. Total gastrectomy with lateral segmentectomy of the liver and resection of the duodenum and the ileum around the Treitz ligament were performed. At 1.5 months after surgery, chemotherapy for malignant lymphoma was successfully initiated.

The efficacy and safety of tazobactam/ceftolozane in combination with metronidazole in Japanese patients with complicated intra-abdominal infections.

Tazobactam/ceftolozane, a novel antimicrobial therapy, is active against Pseudomonas aeruginosa and most extended-spectrum ß-lactamase (ESBL)-producing Enterobacteriaceae. We report the results of the efficacy and safety of tazobactam/ceftolozane in Japanese patients with complicated intra-abdominal infections (cIAI). A multicenter, open-label, noncomparative study (MK-7625A Protocol 013, ClinicalTrials.gov Identifier: NCT02739997) to investigate the efficacy and safety of tazobactam/ceftolozane used in combination with metronidazole in Japanese patients with cIAI was conducted. One hundred Japanese patients with cIAI received tazobactam/ceftolozane 1.5 g (tazobactam 0.5 g/ceftolozane 1 g) plus metronidazole 500 mg intravenously every 8 h for 60 min for 4-14 days. The clinical response rate at the Test-of-Cure visit (TOC; Day 28 ± 2 days) was 92.0% (81/88 subjects). By disease type, the clinical response rates were 92.3% (24/26) for cholecystitis, 100% (6/6) for liver abscess, 93.5% (58/62) for intra-abdominal abscess and 90.2% (55/61) for peritonitis. The per-subject microbiological response rate at the TOC was 90.2% (55/61). Per-pathogen microbiological response rates in the most common baseline pathogens were Escherichia coli 90.2% (37/41), Kebsiella pneumoniae 91.7% (11/12), Streptococcus anginosus 100% (11/11), Streptococcus constellatus 90.0% (9/10) and Bacteroides fragilis 95.2% (20/21). The most common drug-related AEs were aspartate aminotransferase increased (11.0%) and alanine aminotransferase increased (9.0%). No serious drug-related AE was reported during the study. The favorable effect of tazobactam/ceftolozane in the treatment of cIAI suggests that the agent will be useful in clinical practice in Japan.

Pancreatic Chymotrypsin Activity Rather Than Amylase Level Better Predicts Postoperative Pancreatic Fistula.

OBJECTIVE: To assess the predictive value of chymotrypsin activity in pancreatic juice on clinically relevant postoperative pancreatic fistula (CR-POPF) after pancreatic resection, since pancreatic peptidases rather than glycolytic enzymes play a pivotal role in causing tissue damage due to pancreatic leakage. BACKGROUND: The risk of CR-POPF has been estimated based on amylase level in abdominal drainage fluid. METHODS: Eighty-one consecutive patients underwent pancreatoduodenectomy, and postoperative pancreatic juice and drainage fluids were collected for 14 days. The chymotrypsin activity and fluid amylase level in these fluids were measured, and their susceptibility to the elapsed postoperative time and circadian rhythm were evaluated. The predictive value for the development of CR-POPF was compared between assessment of pancreatic chymotrypsin activity versus fluid amylase level. RESULTS: No significant differences in the daily pancreatic chymotrypsin activity were observed, whereas the amylase level in pancreatic juice was susceptible to the postoperative interval and circadian rhythm. CR-POPF developed in 19 patients (23%). Assessment of pancreatic chymotrypsin activity on the first postoperative day predicted CR-POPF with a sensitivity/specificity of 84/87% (area under the curve, 0.855; cut-off value, 0.5 arbitrary units), which was better than measurement of fluid amylase level. Independent predictors of CR-POPF were the day-1 pancreatic chymotrypsin activity (≥0.5 arbitrary units, P < 0.001) and the main pancreatic duct index (<0.25, P = 0.039). CONCLUSIONS: Assessment of pancreatic chymotrypsin activity may allow for more rapid and accurate prediction of CR-POPF than use of conventional diagnostic criteria based on fluid amylase level, enabling individualized surgical procedures and postoperative drain management.

Advanced hepatocellular carcinoma with hepatic vein tumor thrombosis and renal dysfunction after hepatic arterial infusion chemotherapy effectively treated by liver resection with active veno-venous bypass: report of a case.

BACKGROUND: Hepatocellular carcinoma (HCC) patients with hepatic vein tumor thrombosis (HVTT) extending to the inferior vena cava (IVC) have an extremely poor prognosis. Here we report a case of HCC with HVTT and renal dysfunction after hepatic arterial infusion chemotherapy (HAIC) successfully treated by liver resection and active veno-venous bypass. CASE PRESENTATION: A 77-year-old man was diagnosed to have a large HCC with intrahepatic metastases and HVTT extending to the IVC. Due to the advanced stage, HAIC with cisplatin was performed 13 times in a period of 17 months. As a consequence of this treatment, the size of the main HCC markedly decreased, and the advanced part of the HVTT went down to the root of the right hepatic vein (RHV). However, because of renal dysfunction, HAIC with cisplatin was discontinued and right hepatectomy with patch graft venoplasty of the root of the RHV was performed. Because progression of renal dysfunction had to be avoided, veno-venous bypass was activated during IVC clamping to prevent renal venous congestion and hypotension. Histological examination showed foci of a moderately differentiated HCC with extensive fibrosis and necrosis in the main HCC. Histologically, the HVTT in the RHV showed massive necrosis and tightly adhered to the vascular wall of the RHV. The postoperative function of the remnant liver was good, and no further deterioration of renal function was detected. The patient did not show signs of recurrence 15 month after surgery. CONCLUSION: In the present case, HAIC using cisplatin in combination with hepatic resection and patch graft venoplasty of the IVC provided a good long-term outcome with no HCC recurrence. Renal function was preserved by using active veno-venous bypass during IVC clamping to prevent renal venous congestion and hypotension.

A case of pancreatic arteriovenous malformation identified by investigating the cause of upper abdominal pain associated with acute pancreatitis.

A man in his 60s with epigastric pain was diagnosed with acute pancreatitis and subsequently recovered following conservative treatment. However, because of repeated upper abdominal pain and the formation of a pancreatic pseudocyst, he was transferred to our institution for evaluation. Dynamic computed tomography (CT) scanning confirmed abnormal vessels in the tail of the pancreas and early venous return to the splenic vein in the early arterial phase. Abdominal angiography revealed a racemose vascular network in the tail of the pancreas, confirming the presence of an arteriovenous malformation (AVM) in this region. This AVM was thought to be the cause of the acute pancreatitis, so a distal pancreatectomy was performed. The patient's postoperative course was uneventful, and there has been no recurrence at the 7-month postoperative follow-up. Surgical resection has a low recurrence rate and good outcome;thus, if a pancreatic AVM appears difficult to treat with conservative medical therapy, surgical resection appears to be the definitive treatment.

Impact of liver cirrhosis, severity of cirrhosis and portal hypertension on the difficulty of laparoscopic and robotic minor liver resections for primary liver malignancies in the anterolateral segments.

INTRODUCTION: We performed this study in order to investigate the impact of liver cirrhosis (LC) on the difficulty of minimally invasive liver resection (MILR), focusing on minor resections in anterolateral (AL) segments for primary liver malignancies. METHODS: This was an international multicenter retrospective study of 3675 patients who underwent MILR across 60 centers from 2004 to 2021. RESULTS: 1312 (35.7%) patients had no cirrhosis, 2118 (57.9%) had Child A cirrhosis and 245 (6.7%) had Child B cirrhosis. After propensity score matching (PSM), patients in Child A cirrhosis group had higher rates of open conversion (p = 0.024), blood loss >500 mls (p = 0.001), blood transfusion (p < 0.001), postoperative morbidity (p = 0.004), and in-hospital mortality (p = 0.041). After coarsened exact matching (CEM), Child A cirrhotic patients had higher open conversion rate (p = 0.05), greater median blood loss (p = 0.014) and increased postoperative morbidity (p = 0.001). Compared to Child A cirrhosis, Child B cirrhosis group had longer postoperative stay (p = 0.001) and greater major morbidity (p = 0.012) after PSM, and higher blood transfusion rates (p = 0.002), longer postoperative stay (p < 0.001), and greater major morbidity (p = 0.006) after CEM. After PSM, patients with portal hypertension experienced higher rates of blood loss >500 mls (p = 0.003) and intraoperative blood transfusion (p = 0.025). CONCLUSION: The presence and severity of LC affect and compound the difficulty of MILR for minor resections in the AL segments. These factors should be considered for inclusion into future difficulty scoring systems for MILR.

Impact of neoadjuvant chemotherapy on short-term outcomes after simple and complex minimally invasive minor hepatectomy for colorectal liver metastases: A propensity-score matched and coarsened exact matched study.

BACKGROUND: In the last three decades, minimally invasive liver resection has been replacing conventional open approach in liver surgery. More recently, developments in neoadjuvant chemotherapy have led to increased multidisciplinary management of colorectal liver metastases with both medical and surgical treatment modalities. However, the impact of neoadjuvant chemotherapy on the surgical outcomes of minimally invasive liver resections remains poorly understood. METHODS: A multicenter, international, database of 4998 minimally invasive minor hepatectomy for colorectal liver metastases was used to compare surgical outcomes in patients who received neoadjuvant chemotherapy with surgery alone. To correct for baseline imbalance, propensity score matching, coarsened exact matching and inverse probability treatment weighting were performed. RESULTS: 2546 patients met the inclusion criteria. After propensity score matching there were 759 patients in both groups and 383 patients in both groups after coarsened exact matching. Baseline characteristics were equal after both matching strategies. Neoadjuvant chemotherapy was not associated with statistically significant worse surgical outcomes of minimally invasive minor hepatectomy. CONCLUSION: Neoadjuvant chemotherapy had no statistically significant impact on short-term surgical outcomes after simple and complex minimally invasive minor hepatectomy for colorectal liver metastases.