CORRIGENDUM: Correction of the ethical statements. Training efficacy of robotic duct-to-mucosa pancreaticojejunostomy simulation using silicone models for surgical fellows.

[This corrects the article on p. 45 in vol. 106, PMID: 38205096.].

Clinical outcomes of minimally invasive (laparoscopic and robotic) versus open extended cholecystectomy: A multicenter propensity score matched study.

BACKGROUND: This multicenter study aimed to compare the clinical outcomes of minimally invasive extended cholecystectomy (MI-EC) versus open EC (O-EC) for patients with gallbladder cancer (GBC). METHODS: Patients who underwent EC (cholecystectomy, wedge resection of the liver bed, and regional lymphadenectomy) for GBC between 2010 and 2020 in three centers were included in the study. The clinicopathological data were compared after propensity score matching. Additional subgroup analysis on laparoscopic and robotic EC (L-EC and R-EC) was performed. RESULTS: A total of 377 patients were included: 308 for O-EC and 69 for MI-EC, respectively. The MI-EC group had a longer operative time (188.9 vs. 238.1 min, p < .001) and shorter hospital stay (9.0 vs. 7.2 days, p = .007), although no differences were found in operative blood loss, complication rate and survival outcome. In subgroup analysis, L-EC patients had a longer operative time (264.4 vs. 202.0 min, p = .001), compared to R-EC patients with comparable perioperative and survival outcomes. CONCLUSION: Although patients with MI-EC had a longer operation time and higher medical costs, the advantages were enhanced recovery with comparable short- and long-term outcomes. The operation time was less for R-EC patients than for L-EC patients, though the high cost still remains. The surgery type for EC can be selected according to the patient's condition, social status and surgeon's preference.

Training efficacy of robotic duct-to-mucosa pancreaticojejunostomy simulation using silicone models for surgical fellows.

Purpose: In the era of minimally invasive surgery (MIS), robotic pancreatoduodenectomy (PD) is actively performed, and clinical fellows need to thoroughly prepare for MIS-PD during the training process. Although pancreaticojejunostomy (PJ) is a difficult anastomosis that requires repeated practice, there are obstacles preventing its practice that concerns patient safety and limited time in the actual operating room. This study evaluated the efficacy of simulation-based training of robotic duct-to-mucosa PJ using pancreatic and intestinal silicone models using a scoring system. Methods: Three pancreatobiliary clinical fellows who had never performed a real robotic PJ participated in this study. Each trainee, who was well acquainted with master's video created by a senor surgeon, performed the robotic PJ procedures 9 times, and 3 independent pancreatobiliary surgeons assessed the videos and analyzed the scores using a blind method. Results: The mean robotic PJ times for the 3 trainees were 42.8 and 29.1 minutes for the first and 9th videos, respectively. The mean score was 13.8 (range, 6-17) for the first video and 17.7 (range, 15-19) for the 9th video. When comparing earlier and later attempts, the PJ time decreased significantly (2,201.67 seconds vs. 2,045.50 seconds, P = 0.007), whereas test scores increased significantly (total score 14.22 vs. 16.89, P = 0.011). Conclusion: This robotic education system will help pancreatobiliary trainees overcome the learning curves efficiently and quickly without raising ethical concerns associated with animal models or direct practice with human subjects. This will be of practical assistance to trainees preparing for MIS-PD.

A systematic review of progress on hepatocellular carcinoma research over the past 30 years: a machine-learning-based bibliometric analysis.

Introduction: Research on hepatocellular carcinoma (HCC) has grown significantly, and researchers cannot access the vast amount of literature. This study aimed to explore the research progress in studying HCC over the past 30 years using a machine learning-based bibliometric analysis and to suggest future research directions. Methods: Comprehensive research was conducted between 1991 and 2020 in the public version of the PubMed database using the MeSH term "hepatocellular carcinoma." The complete records of the collected results were downloaded in Extensible Markup Language format, and the metadata of each publication, such as the publication year, the type of research, the corresponding author's country, the title, the abstract, and the MeSH terms, were analyzed. We adopted a latent Dirichlet allocation topic modeling method on the Python platform to analyze the research topics of the scientific publications. Results: In the last 30 years, there has been significant and constant growth in the annual publications about HCC (annual percentage growth rate: 7.34%). Overall, 62,856 articles related to HCC from the past 30 years were searched and finally included in this study. Among the diagnosis-related terms, "Liver Cirrhosis" was the most studied. However, in the 2010s, "Biomarkers, Tumor" began to outpace "Liver Cirrhosis." Regarding the treatment-related MeSH terms, "Hepatectomy" was the most studied; however, recent studies related to "Antineoplastic Agents" showed a tendency to supersede hepatectomy. Regarding basic research, the study of "Cell Lines, Tumors,'' appeared after 2000 and has been the most studied among these terms. Conclusion: This was the first machine learning-based bibliometric study to analyze more than 60,000 publications about HCC over the past 30 years. Despite significant efforts in analyzing the literature on basic research, its connection with the clinical field is still lacking. Therefore, more efforts are needed to convert and apply basic research results to clinical treatment. Additionally, it was found that microRNAs have potential as diagnostic and therapeutic targets for HCC.

Biliary ascariasis misidentified as a biliary stent in a patient undergoing liver resection.

Ascaris lumbricoides causes one of the most common soil-transmitted helminthiases globally. The worms mostly infect the human small intestine and elicit negligible or nonspecific symptoms, but there are reports of extraintestinal ectopic ascariasis. We describe a rare case of biliary ascariasis mistaken for biliary stent in a 72-year-old female patient with a history of liver resection. She visited our outpatient clinic complaining of right upper quadrant pain and fever for the past week. She had previously undergone left lateral sectionectomy for recurrent biliary and intrahepatic duct stones 2 years ago. Besides mildly elevated gamma-glutamyl transferase levels, her liver function tests were normal. Magnetic resonance cholangiopancreatography revealed a linear filling defect closely resembling an internal stent from the common bile duct to the right intrahepatic bile duct. A live female A. lumbricoides adult worm was removed by endoscopic retrograde cholangiopancreatography (ERCP). Despite a significant decrease of the ascariasis prevalence in Korea, cases of biliary ascariasis are still occasionally reported. In this study, a additional case of biliary ascariasis, which was radiologically misdiagnosed as the biliary stent, was described in a hepatic resection patient by the worm recovery with ERCP in Korea.

Role of neoadjuvant treatment in resectable pancreatic cancer according to vessel invasion and increase of CA19-9 levels.

BACKGROUND/PURPOSE: The efficacy of neoadjuvant treatment (NAT) for resectable pancreatic cancer remains debatable, particularly in patients with portal vein (PV)/superior mesenteric vein (SMV) contact and elevated serum carbohydrate antigen (CA) 19-9. This study investigated the clinical significance of PV/SMV contact and CA19-9 levels, and the role of NAT in resectable pancreatic cancer. METHODS: A total of 775 patients who underwent surgery for resectable pancreatic cancer between 2007 and 2018 were included. Propensity score-matched (PSM) analysis (1:3) was performed based on tumor size, lymph node enlargement, and PV/SMV contact. Subgroup analyses were performed according to PV/SMV contact and CA19-9 level. RESULTS: Among the patients, 52 underwent NAT and 723 underwent upfront surgery. After PSM, NAT group showed better survival than upfront surgery group (median 30.0 vs 22.0 months, P = .047). In patients with PV/SMV contact, NAT tended to have better survival (30.0 vs 22.0 months, P = .069). CA19-9 >150 U/mL was a poor prognostic factor, with NAT showing a significant survival difference compared with upfront surgery (34.0 vs 18.0 months, P = .004). CONCLUSIONS: Neoadjuvant treatment showed better survival than upfront surgery in resectable pancreatic cancer. In patients with PV/SMV contact or CA19-9 >150 U/mL, NAT showed a survival difference compared to upfront surgery; therefore, NAT could be considered in these patients.

Oncologic Benefits of Neoadjuvant Treatment versus Upfront Surgery in Borderline Resectable Pancreatic Cancer: A Systematic Review and Meta-Analysis.

Neoadjuvant treatment (NAT) followed by surgery is the primary treatment for borderline resectable pancreatic cancer (BRPC). However, there is limited high-level evidence supporting the efficacy of NAT in BRPC. PubMed was searched to identify studies that compared the survival between BRPC patients who underwent NAT and those who underwent upfront surgery (UFS). The overall survival (OS) was compared using intention-to-treat (ITT) analysis. A total of 1204 publications were identified, and 19 publications with 21 data sets (2906 patients; NAT, 1516; UFS, 1390) were analyzed. Two randomized controlled trials and two prospective studies were included. Thirteen studies performed an ITT analysis, while six presented the data of resected patients. The NAT group had significantly better OS than the UFS group in the ITT analyses (HR: 0.63, 95% CI = 0.53-0.76) and resected patients (HR: 0.68, 95% CI = 0.60-0.78). Neoadjuvant chemotherapy with gemcitabine or S-1 and FOLFIRINOX improved the survival outcomes. Among the resected patients, the R0 resection and node-negativity rates were significantly higher in the NAT group. NAT improved the OS, R0 resection rate, and node-negativity rate compared with UFS. Standardizing treatment regimens based on high-quality evidence is fundamental for developing an optimal protocol.

Stool Elastase as an Independent Prognostic Factor in Patients with Pancreatic Head Cancer.

(1) Background: Patients with pancreatic exocrine insufficiency (PEI) have an increased risk of malnutrition, which in turn increases morbidity and mortality and is frequent in pancreatic head cancer. This study aimed to analyze the utility of PEI measured using the stool elastase (SE) level to predict the prognosis of patients with pancreatic head cancer. (2) Methods: Patients who underwent pancreaticoduodenectomy for pancreatic cancer at our institution between 2011 and 2015 were included. Only patients with data on preoperative SE levels were analyzed. Patients were classified into low and high SE groups based on preoperative SE levels (low < 100 µg/g < high). (3) Results: The median preoperative SE level was 67.2 µg/g, and 84 of 143 (58.7%) patients were included in the low SE group. The two groups had significantly different overall survival (OS) and disease-free survival (DFS), and the low SE group had a worse prognosis. In multivariate analysis, SE level < 100 µg/g and lymph node metastasis were independent poor prognostic factors for OS and DFS. (4) Discussion: PEI measured using SE levels is an independent prognostic factor in patients with pancreatic head cancer undergoing pancreaticoduodenectomy. Since poor nutritional status may be related to prognosis in patients with low levels of stool elastase preoperatively, aggressive treatment may be required.

The development and clinical efficacy of simulation training of open duct-to-mucosa pancreaticojejunostomy using pancreas and intestine silicone models.

Purpose: As pancreaticojejunostomy (PJ) is a challenging anastomosis, an education program is needed to train young surgeons to perform PJ. This study evaluated the effects of simulation-based training of open PJ using pancreas and intestine silicone models. Methods: Five videos pancreatobiliary clinical fellows who did not perform PJ participated in this study. After watching the master video created by a senior pancreatobiliary surgeon, each trainee performed the PJ using silicone models and recorded them 10 times using a video camera. Of these videos, 5 were randomly duplicated due to the validation of the scoring system. The scoring system developed consisted of 20 scores. Three pancreatobiliary professors scored their performance by watching videos. Results: The mean procedure time of the 5 trainees was 25.4 minutes (range, 23.5-27.3 minutes) in the first video and 15.8 minutes (range, 13.8-19.1 minutes) in the 10th video. The mean score was 12.6 (range, 5-19) and 18.3 (range, 15-20) in the first and 10th videos, respectively. The scores were similar among the duplicated videos for each supervisor. Conclusion: This education system would help pancreatobiliary trainees to overcome learning curves efficiently without ethical issues related to animal models or direct practice to human patients.

Impact of surgery on survival outcomes for Bismuth type IV Klatskin tumors.

BACKGROUND: Bismuth-Corlette type IV Klatskin tumors have conventionally been considered unresectable. This retrospective study aimed to demonstrate the survival improvement of patients with type IV Klatskin tumors when resected and suggest possible radiological features for R0 resectability. METHODS: Data on type IV Klatskin tumors diagnosed between 2008 and 2019 were reviewed retrospectively. Patients with distant metastasis, concomitant other cancers at the initial state, extensive vascular invasions, poor liver function, and poor general condition were excluded. The survival outcomes of patients and radiologic parameters of bile duct tumors were compared between the curative resection (R0, 1 resection) and non-resection groups. RESULTS: The demographic findings of patients with curative resection (n = 48) and non-resection (n = 111) were comparable. Both were potentially resectable in the initial state. The postoperative morbidity was 22.9% and the 90-day mortality 4.2%. There was a significant difference in the median survival among the curative-intended resection, palliative treatment, and supportive care groups (35, 16, and 12 months, respectively; P < 0.001). DISCUSSION: In patients with type IV Klatskin tumor without extensive tumor invasion into adjacent tissues, including major vessels, surgical resection can be considered for better survival. CLINICAL REGISTRATION NUMBER: IRB No. 2009-100-1157.

Predicting prognosis and evaluating the benefits of adjuvant chemotherapy depending on the tumor location in intrahepatic cholangiocarcinoma: focusing on the involvement of below 2nd bile duct confluence.

Purpose: Intrahepatic cholangiocarcinoma (ICC) has various characteristics according to anatomical, histologic classifications, and its prognoses are different. This study aimed to compare oncologic outcomes according to tumor location (second bile duct confluence) and evaluate the effect of adjuvant chemotherapy. Methods: Clinical data of 318 patients who underwent curative resection for ICC was reviewed. Central type ICC (C-ICC) and peripheral type ICC (P-ICC) were defined when the tumor invades the intrahepatic secondary biliary confluence and when located more peripherally, respectively. Results: A larger tumor size, higher rate of elevated CA 19-9 level, vascular invasion, R1 resection, advanced T stage, and lymph node metastasis were found in C-ICC. C-ICC had poorer overall survival (median, 33 months vs. 58 months; P = 0.001), and the difference was more prominent in the early stage. C-ICC had a higher recurrence rate (68.7% vs. 55.1%, P = 0.014); otherwise, there was no difference in the recurrence patterns. There were no survival benefits of adjuvant chemotherapy in the entire cohort, but there were benefits in advanced stages (T3-4, N1 stage), especially in C-ICC. Conclusion: C-ICC has more aggressive tumor characteristics and poor survival compared to P-ICC. Adjuvant chemotherapy seems to have survival benefits in the advanced stages, especially in the central type.

Can Surgical Resection of Metastatic Lesions Be Beneficial to Pancreatic Ductal Adenocarcinoma Patients with Isolated Lung Metastasis?

In the era of effective chemotherapy on pancreatic ductal adenocarcinoma (PDAC) with distant metastasis, data on the effects of metastatectomy are lacking. So, we investigated the effect of metastatectomy on survival after metastasis in PDAC patients with isolated lung metastasis. This retrospective study analyzed 1342 patients who were histologically diagnosed with PDAC with distant metastasis from January 2007 to December 2018, of which 83 patients had isolated pulmonary metastasis. Additionally, 4263 patients were extracted from the National Cancer Database (NCDB) and analyzed. Log-rank test and Kaplan−Meier survival analysis were used to analyze survival after metastasis. The five-year survival rate was significantly higher in patients who underwent pulmonary metastatectomy than in those who received only chemotherapy or supportive treatment (60.6% vs. 6.2% vs. 0.0%, p < 0.001). A similar trend was observed in the NCDB (two-year survival rate, 27.4% vs. 15.8% vs. 4.7%, p < 0.001). In the multivariate analysis, lung lesion multiplicity (hazard ratio (HR) = 2.004, p = 0.017), metastatectomy (HR = 0.278, p = 0.036), chemotherapy (HR = 0.434, p = 0.024), and chemotherapy cycles (HR = 0.300, p < 0.001) had significant effects on survival. Metastatectomy with primary pancreatic lesions is recommended with effective chemotherapy in PDAC patients with isolated lung metastasis.

Long-Term Oncologic Outcomes for T2 Gallbladder Cancer According to the Type of Surgery Performed and the Optimal Timing for Sequential Extended Cholecystectomy.

BACKGROUND: Sequential extended cholecystectomy (SEC) is currently recommended for T2 and higher gallbladder cancer (GBC) diagnosed after simple cholecystectomy (SC), but the value and timing of re-resection has not been fully studied. We evaluated the long-term oncologic outcomes of T2 GBC according to the type of surgery performed and investigated the optimal timing for SEC. METHODS: Patients diagnosed with T2 GBC who underwent SC, extended cholecystectomy (EC), or SEC between 2002 and 2017 were retrospectively reviewed. Those who underwent other surgical procedures or those with incomplete medical records were excluded. Overall survival (OS) and disease-free survival (DFS) according to the types of surgeries and prognostic factors for OS and DFS were analyzed. Survival analysis was done between groups that were divided according to the optimal cutoff time interval between SC and SEC based on DFS data. RESULTS: Of the 226 T2 GBC patients, 53, 173, and 44 underwent SC, EC, and SEC, respectively. The 5-year OS rate was 50.1%, 73.2%, and 78.7%, and the DFS rate was 46.8%, 66.3%, and 65.2% in the SC, EC, and SEC groups, respectively. EC (p = 0.001 and p = 0.001) and SEC (p = 0.007 and p = 0.065) groups had better 5-year OS and DFS rates than the SC group. Preoperative CA 19-9 level > 37 U/mL (HR 1.56; 95% CI 1.87-2.79; p < 0.001) and N1 stage (HR 2.88; 95% CI 1.76-4.71; p < 0.001) were associated with poorer prognosis. The optimal cutoff interval between SC and SEC was 28 days. Patients who underwent SEC ≤ 28 days after the initial cholecystectomy had better 5-year DFS rates than patients who underwent SEC after > 28 days (75.0% vs. 52.8%, p = 0.023). CONCLUSIONS: SEC is recommended for T2 GBC diagnosed after SC, because SEC provides better survival outcomes than SC alone. A time interval of less than 28 days to SEC is associated with an improved DFS.

In vivo study for the hemostatic efficacy and foreign body reaction of a new powder-type polysaccharide hemostatic agent.

PURPOSE: Various hemostatic agents have been introduced in therapy as postoperative bleeding is a poor prognostic factor for postoperative outcomes. These products can be divided into those that directly promote the hemostatic cascade and those that physically form a barrier by absorbing blood. The latter, powder-type hemostatic agents have the advantages of being inexpensive and more absorbable with less foreign body reactions (FBRs) and are applicable to a relatively wide area. This study was conducted to verify the safety and efficacy of a newly invented polysaccharide product (OOZFIX, Theracion Biomedical), which improves blood absorption and hemostatic effects. METHODS: Two separate animal experiments were performed. The first evaluated FBRs histologically at 3 days, 2 weeks, and 4 weeks, after implantation of OOZFIX in rats, and the second compared hemostatic performance of OOZFIX and Arista AH (Bard) in the porcine liver punch biopsy model. RESULTS: We found minimal FBRs in the 3-day group and no reactions in both the 2-week and 4-week groups after implantation of hemostatic agents. The time to hemostasis of OOZFIX was not significantly different from that of Arista AH (median [interquartile range]: 9 [6-10] minutes vs. 8 [6-10] minutes, respectively; P = 0.522). When comparing the serial bleeding grade tendency, there was no statistical difference between OOZFIX and Arista AH (P = 0.656). CONCLUSION: OOZFIX caused a minimal FBR that disappeared within 2 weeks in vivo, and its hemostatic performance was comparable with that of an existing agent, Arista AH. Further clinical studies are required in the future.

Comparison of oncologic outcomes of extrahepatic cholangiocarcinoma according to tumor location: perihilar cholangiocarcinoma versus distal bile duct cancer.

PURPOSE: Extrahepatic cholangiocarcinoma is distinguished into perihilar cholangiocarcinoma (PHC) and distal bile duct cancer (DBC). The studies for each subtype have been conducted separately. This study compared oncological outcomes between PHC and DBC. METHODS: From 2001 to 2017, patients who underwent surgery at Seoul National University Hospital for PHC or DBC were enrolled. T stage was reclassified for tumor extent as 'confined to' or 'beyond' the bile duct (BD). In survival analysis, stage matching was performed based on tumor extent and lymph node (LN) metastasis. RESULTS: There were 680 patients enrolled: 295 with PHC and 385 with DBC. The R0 resection rate was higher in DBC (77.3% vs. 89.9%, P = 0.001). Tumors confined to BD were more common in PHC (61.7% vs. 37.7%, P = 0.001). The 5-year survival rate (5YSR) was higher in DBC patients (30.8% vs. 47.8%, P = 0.001). After stage matching, DBC patients showed better 5YSR for tumors confined to BD/LN(-) (47.1% vs. 64.3%), confined to BD/LN(+) (22.0% vs. 35.0%), beyond BD/LN(-) (21.9% vs. 49.8%), and beyond BD/LN(+) (9.6% vs. 26.9%). The overall recurrence rate was higher in PHC (59.7% vs. 51.9%, P = 0.045), with no difference in the recurrence types between two groups. Radiation therapy was effective for patients with advanced stage disease (5YSR: 35.8% vs. 29.5%, P = 0.022); adjuvant chemotherapy was effective for patients receiving R1 resection (5YSR: 37.3% vs. 13.2%, P = 0.040). CONCLUSION: Differences were identified in oncological outcomes between PHC and DBC, including pathologic findings and survival outcomes.

Oncologic outcomes according to the location and status of resection margin in pancreas head cancer: role of radiation therapy in R1 resection.

PURPOSE: The clinical significance of margin status in pancreatic head cancer is still controversial due to the nonstandardized definition of R status and pathologic reporting. This study aims to evaluate the impact of the margin status including location and the role of radiation therapy in pancreatic head cancer. METHODS: A total of 314 patients who underwent curative-intent surgery for pancreatic head cancer between 2010 and 2017 were analyzed. Demographics, survival, and local recurrences were compared according to 2 definitions: 0-mm R1 as direct involvement and 1-mm R1 as close resection margin less than 1 mm. The specific margins were divided into 4 groups according to the location around the pancreas: pancreas transection, anterior surface, posterior surface, and vessel (superior mesenteric artery/superior mesenteric vein) margin. RESULTS: The 0-mm R1-rate was 15.6%, and increased to 36.3% in 1-mm R1. The median overall survival rate of 0-mm R0 vs. R1 was 26 months vs. 16 months (P = 0.052) and that of 1-mm R0 vs. R1 was 27 months vs. 18 months, respectively (P = 0.016). In individual margins, posterior, anterior surface, and pancreas transection margin involvement were associated with poor outcome, and the 1 mm posterior surface involvement was an independent risk factor for disease-free survival (hazard ratio, 1.63). Adjuvant radiation therapy had oncologic benefits, especially in R1 patients (P = 0.011) compared to R0 patients (P = 0.088). CONCLUSION: Margin status, especially 1-mm R1 status is an important predictive factor, and involved posterior surface has a clinical impact. Patients with positive margins should be considered adjuvant radiation therapy.

Risk factors deteriorating severe exocrine pancreatic insufficiency measured by stool elastase after pancreatoduodenectomy and the risk factors for weight loss.

PURPOSE: The measurement of stool elastase (SE) level is useful for evaluating pancreatic exocrine function. This study aimed to determine the risk factors for severe exocrine pancreatic insufficiency (EPI) after pancreatoduodenectomy (PD), and analyze serial changes in nutritional markers and weight based on the SE level. METHODS: Among patients who underwent PD for periampullary disease, patients whose preoperative and postoperative SE levels were measured were included in the study. The deteriorated (exocrine function) group comprised patients whose SE levels decreased from ≥100 µg/g preoperatively to <100 µg/g postoperatively. Patients whose weight 12 months postoperatively was greater than that 3 months postoperatively were classified into the weight-recovery group. RESULTS: Of the 202 included patients, the deteriorated group had a higher incidence of preoperative SE level above 200 µg/g, benign pathology, and the presence of a clinically relevant postoperative pancreatic fistula than the maintained group. Patients who did not undergo weight recovery had a higher rate of history of adjuvant radiotherapy compared to the no-recovery group. CONCLUSION: The evaluation of EPI by measuring SE alone is not sufficient because it does not reflect the nutritional status of patients, and a comprehensive approach that considers other parameters is required for EPI management.

ROBOT-assisted pancreatoduodenectomy in 300 consecutive cases: Annual trend analysis and propensity score-matched comparison of perioperative and long-term oncologic outcomes with the open method.

BACKGROUND/PURPOSE: We previously reported perioperative and oncologic outcomes of robot-assisted pancreatoduodenectomy (RAPD); however, the follow-up period in RAPD was relatively short, and disease-matched survival analyses were lacking. Therefore, this study investigated time trends of perioperative and long-term disease-matched outcomes of RAPD. METHODS: Annual clinicopathologic outcomes of 328 patients with RAPD between 2015 and 2020 were analyzed and compared with 929 patients with open PD using the propensity score-matched (PSM) analysis based on postoperative pancreatic fistula (POPF) risk and oncologic variables in malignant patients. RESULTS: Robot-assisted pancreatoduodenectomy cases increased from 10 (6.3%) in 2015 to 116 (50.2% of total PD) in 2020, with malignancy proportion increasing from 50.0% to 80.2%. POPF risk-based PSM analysis showed that compared with open PD, RAPD had younger patients (63.7 vs 65.6 years, P = .018), longer operation time (339.1 vs 290.0 min, P < .001); however, estimated blood loss (P = .275), complications (17.1% vs 18.3%, P = .702), and clinically relevant POPF (9.8% vs 11.1%, P = .584) were similar with shorter postoperative hospital stay (10.8 vs 15.6 days, P < .001). In disease and stage-matched malignant patients, R0 resection (93.9% vs 91.2%, P = .376), total retrieved lymph node (18.2 vs 19.9, P = .058), and 5-year survival rate (57.3% vs 60.6%, P = .406) were similar between RAPD and open PD, also in pancreatic cancer patients (31.6% vs 26.3%, P = .068). CONCLUSIONS: Robot-assisted pancreatoduodenectomy demonstrated similar perioperative outcomes with earlier recovery and equivalent long-term survival with open PD. RAPD is safe and feasible for periampullary lesions, including pancreatic cancers, and its role will expand in the era of minimally invasive surgery.

A retrospective multicentre study on the evaluation of perioperative outcomes of single-port robotic cholecystectomy comparing the Xi and SP versions of the da Vinci robotic surgical system.

BACKGROUND: Single-incision robotic cholecystectomy (SIRC) is widely performed with both the da Vinci Xi system (Xi) and the da Vinci SP system (SP). But there are limited numbers of studies comparing these platforms. METHODS: Patients who underwent SIRC between 2019 and 2020 were enrolled. Patient demographics, intraoperative factors, postoperative complications, postoperative pain were compared using a one-to-one propensity score matching (PSM). RESULTS: Overall, 258 patients underwent SIRC with Xi and 72 with SP. After PSM, there were significant differences between the Xi and SP in operation time at console and numeric rating scale for postoperative pain, but no difference in total operation time and postoperative complications. The SP group showed more estimated blood loss. CONCLUSIONS: Despite the statistical difference, clinical benefit was not significant. Both platforms can be safe and feasible to perform SIRC, but further investigation including the surgeon's workload and ergonomics is needed as a prospective study.

Clinical characteristics of patients with malignancy and long-term outcomes of surgical treatment of patients with choledochal cyst.

PURPOSE: There are few reports of postoperative long-term malignant risk or postoperative sequelae after surgery for choledochal cysts (CCs). This study aimed to analyze the clinical characteristics of patients with malignancy and the long-term results of operated CC. METHODS: The patients who underwent surgical treatments for CC between 2003 and 2020 at Seoul National University Hospital were enrolled. Clinicopathologic factors and pre-/postoperative computed tomography or magnetic resonance imaging were reviewed. RESULTS: Of the 153 patients, Todani classification Ic (36.6%), C-P type (43.8%) anomalous pancreaticobiliary duct union were the most common type respectively. Fourteen patients (9.2%) had biliary tract cancer and a comparison of patients with and without malignancy showed that the diameter of cyst was significantly lower in malignant patients and malignancy was observed to be significantly higher in P-C type. The incidence of long-term complications was 9.8%, and the median time interval was 30 months. The 2 most common complications were cholangitis and stricture (60.0%). There was one case of new cancer near the intrapancreatic remnant bile duct. CONCLUSION: Of the resected CCs, 9.2% had a combined malignancy on the biliary tracts. Long-term complications such as cholangitis, anastomotic stricture, and new cancers may occur. Therefore, continuous surveillance is required.