First report of Pythium myriotylum causing root rot on soybean in the Republic of Korea.

Pythium species are one of the most important groups of seedling pathogens affecting soybean yield. In July 2023, eight soybean plants (cv. Daewon, V3 to V4 stage) that were wilted with browning at their lower stems were discovered in a field located in Suwon, Korea. The disease incidence was 0.1% in an area of 0.1 ha, and severity was 100%. The eight plants exhibited brown root rot when removed from the soil. Their main roots were almost completely rotten, with only a few rootlets remaining. Symptomatic stem tissues (approximately 0.5 × 1 to 1.5 cm2) were sampled from the crown of each plant, disinfected with 75% ethanol for 30 sec and 1% NaOCl for 1 min, rinsed with sterile distilled water, and incubated on sterile filter paper for 3 days at 25°C. White hyphae emerging from the tissues were isolated and cultured on potato dextrose agar (PDA) plates, resulting in eight isolates. To further investigate their morphological features, the isolates were subcultured on PDA media at 25°C in the dark for 7 days. The colonies formed dense, white, fluffy aerial mycelia. The oogonia were globose with a smooth surface, typically appearing terminal, and had an average diameter of 31 µm (28 to 36 µm). The oospores were aplerotic, with an average diameter of 29 µm (26 to 31 µm). These morphological characteristics closely matched those of Pythium myriotylum as described in Van der Plaats-Niterink (1981) and Tomioka et al. (2013). The internal transcribed spacer (ITS) region and cytochrome c oxidase subunit I (COX1) were amplified using the primer pairs ITS1/ITS4 and OomCoxI-Levlo/OomCoxI-Levup (Robideau et al. 2011; White et al. 1990). Sequences from the eight isolates (SW2-4, SW-DF2, SW-DF3, SW-DF7, SW-DF9, SW-DF13, SW-DF14, and SW-DF16) were deposited in GenBank under following accession numbers: ITS (PP145893; PP913926 to PP913932) and COX1 (PP853484; PP977183 to PP977189). These sequences showed 100% homology with those of P. myriotylum strain CBS25470 (GenBank accession no. HQ643701, HQ708745). One isolate SW2-4 was selected to assess its pathogenicity using soil infestation method. The isolate SW2-4 was cultured on 20 ml of V8 juice agar medium per petri dish (9 cm in diameter) in the dark at 26°C for 10 days. Cultures collected from 4 petri dishes were homogenized with 40 ml of sterile distilled water, and then mixed with 1.1 liter of commercial potting soil that had been pre-soaked in 1 liter of sterile distilled water. Next, 450 ml of this Pythium-infested soil mixture was placed into pots (12 cm in diameter). Ten seeds of soybean (cv. Daewon) were then sown on top of the infested soil and covered with 2 cm of uninfested soil. Another ten seeds (cv. Daewon) were sown in the uninfested soil as controls. The pots were placed in a growth chamber (26°C, light: dark cycle of 12:12h). The experiments were repeated six times. The inoculated plants grew slowly, and dark-brown lesions appeared at the stem base 5 days after inoculation. Affected plants began to wilt 10 days after inoculation, whereas the control plants showed no symptoms and remained healthy throughout the experiments. An oomycete pathogen was re-isolated from the symptomatic stem tissue to fulfill Koch's postulates, while none was isolated from the control plants. The pathogen's morphological characteristics and DNA sequences (ITS and COX1) were confirmed to be identical to those of the inoculated isolate. To the best of our knowledge, this is the first report of P. myriotylum causing root rot and wilting in soybean in the Republic of Korea.

Interobserver Variability in the International Study Group for Pancreas Surgery (ISGPS)-Defined Complications After Pancreatoduodenectomy: An International Cross-Sectional Multicenter Study.

OBJECTIVE: To determine the interobserver variability for complications of pancreatoduodenectomy as defined by the International Study Group for Pancreatic Surgery (ISGPS) and others. SUMMARY BACKGROUND DATA: Good interobserver variability for the definitions of surgical complications is of major importance in comparing surgical outcomes between and within centers. However, data on interobserver variability for pancreatoduodenectomy-specific complications are lacking. METHODS: International cross-sectional multicenter study including 52 raters from 13 high-volume pancreatic centers in 8 countries on 3 continents. Per center, 4 experienced raters scored 30 randomly selected patients after pancreatoduodenectomy. In addition, all raters scored six standardized case vignettes. This variability and the 'within centers' variability were calculated for twofold scoring (no complication/grade A vs grade B/C) and threefold scoring (no complication/grade A vs grade B vs grade C) of postoperative pancreatic fistula (POPF), post-pancreatoduodenectomy hemorrhage (PPH), chyle leak (CL), bile leak (BL), and delayed gastric emptying (DGE). Interobserver variability is presented with Gwet's AC-1 measure for agreement. RESULTS: Overall, 390 patients after pancreatoduodenectomy were included. The overall agreement rate for the standardized cases vignettes for twofold scoring was 68% (95%-CI: 55%-81%, AC1 score: moderate agreement) and for threefold scoring 55% (49%-62%, AC1 score: fair agreement). The mean 'within centers' agreement for twofold scoring was 84% (80%-87%, AC1 score; substantial agreement). CONCLUSION: The interobserver variability for the ISGPS defined complications of pancreatoduodenectomy was too high even though the 'within centers' agreement was acceptable. Since these findings will decrease the quality and validity of clinical studies, ISGPS has started efforts aimed at reducing the interobserver variability.

Early postoperative fever as a predictor of pancreatic fistula after pancreaticoduodenectomy: a single-center retrospective observational study.

BACKGROUND: The connection between early postoperative fever and clinically relevant postoperative pancreatic fistula (CR-POPF) after pancreaticoduodenectomy remains unclear. This study aimed to investigate this association and assess the predictive value of early postoperative fever for CR-POPF. METHODS: This retrospective observational study included adult patients who underwent pancreaticoduodenectomy at a tertiary teaching hospital between 2007 and 2019. Patients were categorized into those with early postoperative fever (≥ 38 °C in the first 48 h after surgery) and those without early postoperative fever groups. Weighted logistic regression analysis using stabilized inverse probability of treatment weighting (sIPTW) and multivariable logistic analysis were performed. The c-statistics of the receiver operating characteristic curves were calculated to evaluate the impact on the predictive power of adding early postoperative fever to previously identified predictors of CR-POPF. RESULTS: Of the 1997 patients analyzed, 909 (45.1%) developed early postoperative fever. The overall incidence of CR-POPF among all the patients was 14.3%, with an incidence of 19.5% in the early postoperative fever group and 9.9% in the group without early postoperative fever. Early postoperative fever was significantly associated with a higher risk of CR-POPF after sIPTW (adjusted odds ratio [OR], 1.73; 95% confidence interval [CI], 1.34-2.22; P < 0.001) and multivariable logistic regression analysis (adjusted OR, 1.88; 95% CI, 1.42-2.49; P < 0.001). The c-statistics for the models with and without early postoperative fever were 0.76 (95% CI, 0.73-0.79) and 0.75 (95% CI, 0.72-0.78), respectively, showing a significant difference between the two (difference, 0.02; 95% CI, 0.00-0.03; DeLong's test, P = 0.005). CONCLUSIONS: Early postoperative fever is a significant but not highly discriminative predictor of CR-POPF after pancreaticoduodenectomy. However, its widespread occurrence limits its applicability as a predictive marker.

Comparing clinical and genomic features based on the tumor location in patients with resected pancreatic cancer.

BACKGROUND: Pancreatic cancer is anatomically divided into pancreatic head and body/tail cancers, and some studies have reported differences in prognosis. However, whether this discrepancy is induced from the difference of tumor biology is hotly debated. Therefore, we aimed to evaluate the differences in clinical outcomes and tumor biology depending on the tumor location. METHODS: In this retrospective cohort study, we identified 800 patients with pancreatic ductal adenocarcinoma who had undergone upfront curative-intent surgery. Cox regression analysis was performed to explore the prognostic impact of the tumor location. Among them, 153 patients with sufficient tumor tissue and blood samples who provided informed consent for next-generation sequencing were selected as the cohort for genomic analysis. RESULTS: Out of the 800 patients, 500 (62.5%) had pancreatic head cancer, and 300 (37.5%) had body/tail cancer. Tumor location in the body/tail of the pancreas was not identified as a significant predictor of survival outcomes compared to that in the head in multivariate analysis (hazard ratio, 0.94; 95% confidence interval, 0.77-1.14; P = 0.511). Additionally, in the genomic analyses of 153 patients, there were no significant differences in mutational landscapes, distribution of subtypes based on transcriptomic profiling, and estimated infiltration levels of various immune cells between pancreatic head and body/tail cancers. CONCLUSIONS: We could not find differences in prognosis and tumor biology depending on tumor location in pancreatic ductal adenocarcinoma. Discrepancies in prognosis may represent a combination of lead time, selection bias, and clinical differences, including the surgical burden between tumor sites.

Re-evaluation of risk and oncological outcomes of resection of veins and arteries in the resection of pancreatic cancer.

BACKGROUND: Advances in chemotherapy have led to increasing major vascular resection during pancreatectomy which has been contraindicated due to high morbidity. This study aimed to verify the safety and oncological outcomes of vascular resection during pancreatectomy in the era of neoadjuvant therapy. METHODS: Data from patients who underwent surgery for pancreatic cancer at Seoul National University Hospital between 2001 and 2021 were reviewed. Clinicopathological outcomes were analyzed according vessel resection. A propensity-score-matched (PSM) analysis was performed to evaluate survival outcomes. RESULTS: Of 1596 patients, the proportion of those who underwent vascular resection increased from 9.2% to 23.4% over time divided into 5-year intervals. There were no differences in major complications (15.6% vs. 13.0%; p = .266) and 30-day mortality rate (0.3% vs. 0.6%; p = .837) between the vascular and nonvascular resection groups. After PSM, the vascular resection group demonstrated comparable survival outcome with the nonvascular resection group (5 year-survival-rate 20.4 vs. 23.7%; p = .194). Arterial resection yielded comparable survival outcome with nonvascular resection (5 year-survival-rate 38.1% vs. 23.7%; p = .138). CONCLUSIONS: Appropriate vascular resection-even arterial-is safe and effective in patients carefully selected for radical surgery in the era of neoadjuvant therapy. Further studies are needed to determine the optimal indication and method for vascular resection in patients with pancreatic cancer.

First report of soybean root rot caused by Fusarium falciforme in the Republic of Korea.

Phytopathogenic Fusarium species causing root and stem rot diseases in susceptible soybean (Glycine max (L.) Merrill) are a major threat to soybean production worldwide. Several Fusarium species have been reported to infect soybean plants in the Republic of Korea, including F. solani, F. oxysporum, F. fujikuroi, and F. graminearum (Cho et al., 2004; Choi et al., 2019; Kang et al., 2020). During the nationwide survey of soybean diseases in 2015, soybean plants showing symptoms of leaf chlorosis, wilting, and shoot death were found in soybean fields in Seosan, Chungnam. Fusarium isolates were obtained from the margins of sterilized necrotic symptomatic and asymptomatic regions of the stem tissues of diseased samples by culturing on potato dextrose agar (PDA). To examine the morphological characteristics, isolates were cultured on PDA at 25°C in the darkness for 10 days. Colonies produced white aerial mycelia with apricot pigments in the medium. Macroconidia were hyaline, slightly curved in shape with 3 or 4 septa, and their average length and width were 34.6± 0.56 µm (31.4 to 37.8 µm) and 4.7±0.16 µm (4.1 to 5.8 µm), respectively (n = 20). Microconidia were elongated, oval with 0 or 1 septum, and their average length and width were 11.4±0.87 and 5.2±0.32 µm, respectively (n = 20). The colonies and conidia exhibited morphological similarities to those of F. falciforme (Xu et al., 2022). Using the primers described by O'Donnell et al. (2008), identity of a representative strain '15-110' was further confirmed by sequencing portions of two genes, the translation elongation factor 1-alpha (EF-1α) and the second largest subunit of RNA polymerase II (RPB2). The two sequences (GenBank accession No. OQ992718 and OR060664) of 15-110 were 99% similar to those of two F. falciforme strains, 21BeanYC6-14 (GenBank accession nos. ON375419 and ON331931), and 21BeanYC6-16 (GenBank accession nos. ON697187 and ON331933). To test the pathogenicity, a single-spore isolate was cultured on carnation leaf agar (CLA) at 25℃ for 10 days. Pathogenicity test was performed by root-cutting assays using 14-day-old soybean seedlings of 'Daewon' and 'Taekwang'. Ten-day-old mycelia of 15-110 were collected from the CLA plates by scraping with distilled water, and the spore suspension was filtered and diluted to 1 × 106 conidia/mL. The roots of the soybean seedlings were partially cut and inoculated by soaking in the diluted spore suspension for two hours. The seedlings were then transplanted into 12 cm plastic pots (11 cm in height) and grown in a growth chamber at 25°C, 14h light/10h dark for 2 weeks. The infected plants exhibited wilting, observed brown discoloration on the root, and eventually died within 2 weeks, whereas the control plants inoculated with sterile water remained healthy. F. falciforme 15-110 was reisolated from infected plants, but not from the uninoculated controls. The morphology of the re-isolated fungus on PDA and its target gene sequences were identical to those of the original colony. To the best of our knowledge, this is the first report of root rot in soybean caused by F. falciforme in the Republic of Korea. Fusarium spp. induce a range of diseases in soybean plants, including root rot, damping-off, and wilt. Given the variable aggressiveness and susceptibility to fungicides among different Fusarium species, it is imperative to identify the Fusarium species posing a threat to soybean production. This understanding is crucial for developing a targeted and tailored disease management strategy to control Fusarium diseases.

Association between hypotension during pancreatectomy and development of postoperative diabetes.

CONTEXT: With advancements in long-term survival after pancreatectomy, post-pancreatectomy diabetes has become a concern, and the risk factors are not established yet. Pancreatic islets are susceptible to ischemic damage, though there is a lack of clinical evidence regarding glycemic deterioration. OBJECTIVE: To investigate association between hypotension during pancreatectomy and development of post-pancreatectomy diabetes. DESIGN: In this retrospective, longitudinal cohort study, we enrolled patients without diabetes who underwent distal pancreatectomy or pancreaticoduodenectomy between January 2005 and December 2018, from two referral hospitals in Korea. MAIN OUTCOME MEASURES: Intraoperative hypotension [IOH] was defined as a 20% or greater reduction in systolic blood-pressure. The primary and secondary outcomes were incident diabetes and postoperative Homeostatic Model Assessment [HOMA] indices. RESULTS: We enrolled 1,129 patients (average age, 59 years; 49% men; 35% distal pancreatectomy). IOH occurred in 83% (median duration, 25 minutes; interquartile range [IQR], 5-65). During a median follow-up of 3.9 years, diabetes developed in 284 patients (25%). The cumulative incidence of diabetes was proportional to increases in the duration and depth of IOH (P < 0.001). For the median duration in an IOH when compared to a reference time of 0 minute, the hazard ratio [HR] was 1.48 (95% CI, 1.14-1.92). The effect was pronounced with distal pancreatectomy compared to pancreaticoduodenectomy. Furthermore, the duration of IOH was inversely correlated with 1-year HOMA beta-cell function (P < 0.002), but not with HOMA insulin resistance. CONCLUSIONS: These results support the hypothesis that IOH during pancreatectomy may elevate risk of diabetes by inducing beta cell insufficiency.

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.].

First report of soybean root rot caused by Fusarium proliferatum in the Republic of Korea.

Fusarium species are widespread soilborne pathogens that can cause damping-off, root rot, and wilting in soybean [Glycine max (L.) Merrill], subsequently leading to significant yield suppression. Several Fusarium spp. have already been documented for their pathogenicity on soybean plants in the Republic of Korea. The nationwide monitoring of soybean diseases continues to identify new pathogenic Fusarium spp. In 2016, five plant samples at R3-R4 growth stages, showing symptoms of wilting in the upper parts and root rot, were collected in Suwon, Gyeonggi, Republic of Korea. Fungal colonies were obtained from the diseased root samples, with the surface sterilized in 1% sodium hypochlorite for 2 min, rinsed thrice with sterile distilled water, and placed on water agar at 25°C. Five isolates were collected and purified by single-spore isolation. The fungal mycelium was subsequently cultivated on potato dextrose agar for ten days. The isolates produced abundant, aerial, and white mycelium and became purple in old cultures. Macroconidia were slender, falcate to almost straight, usually 3 to 5 septated, and thin-walled. Microconidia were formed in chains from polyphalides, clavate or oval, usually single-celled with a flattened base. These characteristics of isolates were consistent with the description of F. proliferatum (Leslie and Summerrell 2006), and the representative isolate 16-19 was selected for molecular identification to confirm its identity as F. proliferatum. Two evolutionarily conserved genes, the translation elongation factor 1-alpha (EF-1α) and the second-largest subunit of RNA polymerase II (RPB2) genes, were partially amplified using the primers described by O'Donnell et al. (2008), resulting in nucleotide sequences of 680 and 382 base pairs, respectively. These two sequences (GenBank accession numbers: OQ992720 and OR060666) showed 100 and 99.5% identity to the EF-1α and RPB2 of F. proliferatum A40 (GenBank accession numbers: KP964907 and KP964842). For the Petri-dish pathogenicity assay (Broders et al. 2007), five surface-sterilized seeds were placed on water agar media with either sterile water or actively growing '16-19' culture. After 7 days of incubation in a growth chamber (25°C; 12-hour photoperiod), brown lesions were observed on the roots of the inoculated plants, while no symptoms were observed in the sterile water-treated controls. The experiment was conducted three times. For root-cut pathogenicity assay, conidial suspension (1×106 conidia/ml) of the isolate '16-19' was prepared with harvested mycelia cultured on PDA for 10 days with sterile water. The roots of 10-day-old soybean seedlings were partially cut and soaked in either the suspension or sterile water for 2 hours. The seedlings were transplanted into 12 cm plastic pots (11 cm in height) and grew in a greenhouse (26 ± 3°C, 13-h photoperiod). The experiment followed a completely randomized design with three replicates (i.e. three plants in a pot), and it was repeated twice. The inoculated plants began to wilt 7 days after inoculation, while the sterile water-treated controls remained healthy. Ten days after inoculation, all plants were collected, washed under running tap water, and evaluated for the presence and severity of root rot using a 0-4 scale (Chang et al. 2015). The inoculated plants exhibited reduced vigor and developed dark brown lesions on their roots. F. proliferatum was reisolated from symptomatic root tissues of the infected plants, while not from those of the controls. Its colony and spores were morphologically identical to those of the original isolate. F. proliferatum was previously reported as a causative agent of soybean root rot in the United States (Díaz Arias et al. 2011) and Canada (Chang et al. 2015). This is the first report of soybean root rot caused by F. proliferatum in the Republic of Korea. This finding implies that F. proliferatum may potentially threaten soybean production in the Republic of Korea and suggests that effective disease management strategies should be established for soybean protection against the disease, along with continuous surveillance.

Systematic review on surveillance for non-resected branch-duct intraductal papillary mucinous neoplasms of the pancreas.

BACKGROUND: The management of branch-duct type intraductal papillary mucinous neoplasms (BD-IPMN) varies in existing guidelines. This study investigated the optimal surveillance protocol and safe discontinuation of surveillance considering natural history in non-resected IPMN, by systematically reviewing the published literature. METHODS: This review was guided by PRISMA. Research questions were framed in PICO format "CQ1-1: Is size criteria helpful to determine surveillance period? CQ1-2: How often should surveillance be carried out? CQ1-3: When should surveillance be discontinued? CQ1-4: Is nomogram predicting malignancy useful during surveillance?". PubMed was searched from January-April 2022. RESULTS: The search generated 2373 citations. After screening, 83 articles were included. Among them, 33 studies were identified for CQ1-1, 19 for CQ1-2, 26 for CQ1-3 and 12 for CQ1-4. Cysts <1.5 or 2 cm without worrisome features (WF) were described as more indolent, and most studies advised an initial period of surveillance. The median growth rate of cysts <2 cm ranged from 0.23 to 0.6 mm/year. Patients with cysts <2 cm showing no morphological changes and no WF after 5-years of surveillance have minimal malignancy risk of 0-2%. Two nomograms created with over 1000 patients had AUCs of around 0.8 and appear to be feasible in a real-world practice. CONCLUSIONS: For patients with suspected BD-IPMN <2 cm and no other WF, less frequent surveillance is recommended. Surveillance may be discontinued for cysts that remain stable during 5-year surveillance, with consideration of patient condition and life expectancy. With this updated surveillance strategy, patients with non-worrisome BD-IPMN should expect more streamlined management and decreased healthcare utilization.

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.

Examining neoadjuvant treatment candidates in resectable pancreatic cancer based on tumor-vessel interactions and CA 19-9 levels: a retrospective cohort study.

INTRODUCTION: The applicability of neoadjuvant treatment (NAT) for resectable pancreatic ductal adenocarcinoma (PDAC) has arisen, however, high-level evidence is lacking. This study aimed to explore patient subgroups with high-risk resectable PDAC for selecting candidates who may benefit from NAT. METHODS: The 1132 patients with resectable or borderline resectable PDAC who underwent surgery between 2007 and 2021 were retrospectively reviewed. Patients with resectable PDAC without contact of major vessels (R-no contact) ( n =651), with contact of portal vein or superior mesenteric vein (PV/SMV) ≤180° (R-contact) ( n =306), and borderline resectable PDAC without arterial involvement (BR-V) ( n =175) were analyzed. RESULTS: The mean age was 64.3±9.8 years, and 647 patients (57.2%) were male. The median follow-up was 26 months in the entire cohort. Patients with resectable PDAC without vascular contact had the most improved overall survival (OS) (median; 31.5 months). OS did not significantly differ between NAT and upfront surgery in the entire resectable PDAC cohort. However, in R-contact group, NAT showed significantly improved OS compared to upfront surgery (33 vs. 23 months). Neoadjuvant FOLFIRINOX was showed a better OS than gemcitabine-based regimens in patients who underwent NAT (34 vs. 24 months). NAT was associated with a better survival in the patients with CA 19-9 level ≥150 U/ml, only when the tumor has PV/SMV contact in resectable disease (40 vs. 19 months, P =0.001). CONCLUSIONS: NAT can be considered as an effective treatment in patients with resectable PDAC, particularly when the tumor is in contact with PV/SMV and CA 19-9 ≥150 U/ml.

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.

Outcomes after distal pancreatectomy with or without splenectomy for intraductal papillary mucinous neoplasm: international multicentre cohort study.

BACKGROUND: International guidelines on intraductal papillary mucinous neoplasm (IPMN) recommend a formal oncological resection including splenectomy when distal pancreatectomy is indicated. This study aimed to compare oncological and surgical outcomes after distal pancreatectomy with or without splenectomy in patients with presumed IPMN. METHODS: An international, retrospective cohort study was undertaken in 14 high-volume centres from 7 countries including consecutive patients after distal pancreatectomy for IPMN (2005-2019). Patients were divided into spleen-preserving distal pancreatectomy (SPDP) and distal pancreatectomy with splenectomy (DPS). The primary outcome was lymph node metastasis (LNM). Secondary outcomes were overall survival, duration of operation, blood loss, and secondary splenectomy. RESULTS: Overall, 700 patients were included after distal pancreatectomy for IPMN; 123 underwent SPDP (17.6%) and 577 DPS (82.4%). The rate of malignancy was 29.6% (137 patients) and the overall rate of LNM 6.7% (47 patients). Patients with preoperative suspicion of malignancy had a LNM rate of 17.2% (23 of 134) versus 4.3% (23 of 539) among patients without suspected malignancy (P < 0.001). Overall, SPDP was associated with a shorter operating time (median 180 versus 226 min; P = 0.001), less blood loss (100 versus 336 ml; P = 0.001), and shorter hospital stay (5 versus 8 days; P < 0.001). No significant difference in overall survival was observed between SPDP and DPS for IPMN after correction for prognostic factors (HR 0.50, 95% c.i. 0.22 to 1.18; P = 0.504). CONCLUSION: This international cohort study found LNM in 6.7% of patients undergoing distal pancreatectomy for IPMN. In patients without preoperative suspicion of malignancy, SPDP seemed oncologically safe and was associated with improved short-term outcomes compared with DPS.

Optimal Surveillance Interval of Branch Duct Intraductal Papillary Mucinous Neoplasm of the Pancreas.

Importance: Despite the increasing prevalence of intraductal papillary mucinous neoplasm (IPMN), data on the growth and malignant conversion rates based on long-term surveillance cohorts are limited. Many international guidelines recommend surveillance for benign lesions, but the optimal interval and duration are unclear. Objective: To determine the optimal surveillance protocol for IPMN and propose which patients may be exempted from surveillance. Design, Setting, and Participants: This large-scale, international cohort study examined data of 3825 patients with IPMN treated at 5 tertiary pancreatic centers. Included were patients with branch duct (BD) IPMN who underwent surveillance or surgery between January 1, 1988, and December 31, 2020. After a thorough review, 3656 patients were included in the analytic sample. Changes in cyst size, worrisome features or high-risk stigmata, and malignant conversion rates were assessed. Patients who underwent surveillance over 5 years were compared to suggest discontinuation of surveillance protocol. Clinical data collection began in January 1, 2021, and the mean (SD) follow-up duration was 84 (47.7) months. The data analysis was performed from May 2, 2022, through September 14, 2022. Exposure: The patients with BD-IPMN were followed up based on International Association of Pancreatology guidelines. Patients with suspicious malignant neoplasms during surveillance underwent surgical resection. Main Outcome and Measures: The main outcome of this study was the optimal follow-up interval and duration of BD-IPMN surveillance. The association among cyst size, growth rate, and progression was examined using descriptive statistics. Results: Of the 3656 patients with BD-IPMN in the analytic sample (1973 [54.0%] female; mean [SD] age, 63.7 [10.2] years), 172 (4.7%) were confirmed to have malignant lesions through surgery. Considering cyst growth, the time to develop worrisome features, and malignant conversion, a 1.5-, 1-, and 0.5-year surveillance interval could be optimal for cysts smaller than 20 mm, 20 to 30 mm, and 30 mm, respectively, after initial short-term (6-month) follow-up. Patients with cysts smaller than 20 mm, no worrisome features, and no growth during 5-year surveillance did not show malignant conversion after 5 years of follow-up and had time to progression of greater than 10 years. Conclusions: These findings suggest that BD-IPMN surveillance may depend on the size of the cyst and morphologic changes at the initial 6-month follow-up. For patients with small cysts (ie, <20 mm) with no morphologic changes during the initial 5-year surveillance period, surveillance may be discontinued for those unfit for surgery or who have a limited life expectancy of 10 years or less.

Glucolipotoxicity Suppressed Autophagy and Insulin Contents in Human Islets, and Attenuation of PERK Activity Enhanced Them in an ATG7-Dependent Manner.

BACKGRUOUND: Administration of pancreatic endoplasmic reticulum kinase inhibitor (PERKi) improved insulin secretion and hyperglycemia in obese diabetic mice. In this study, autophagic balance was studied whether to mediate it. METHODS: Human islets were isolated from living patients without diabetes. PERKi GSK2606414 effects were evaluated in the islets under glucolipotoxicity by palmitate. Islet insulin contents and secretion were measured. Autophagic flux was assessed by microtubule associated protein 1 light chain 3 (LC3) conversion, a red fluorescent protein (RFP)-green fluorescent protein (GFP)- LC3 tandem assay, and P62 levels. For mechanical analyses, autophagy was suppressed using 3-methyladenine in mouse islets. Small interfering RNA for an autophagy-related gene autophagy related 7 (Atg7) was transfected to interfere autophagy. RESULTS: PERKi administration to mice decreased diabetes-induced P62 levels in the islets. Glucolipotoxicity significantly increased PERK phosphorylation by 70% and decreased insulin contents by 50% in human islets, and addition of PERKi (40 to 80 nM) recovered both. PERKi also enhanced glucose-stimulated insulin secretion (6-fold). PERKi up-regulated LC3 conversion suppressed by glucolipotoxicity, and down-regulated P62 contents without changes in P62 transcription, indicating enhanced autophagic flux. Increased autophagosome-lysosome fusion by PERKi was visualized in mouse islets, where PERKi enhanced ATG7 bound to LC3. Suppression of Atg7 eliminated PERKi-induced insulin contents and secretion. CONCLUSION: This study provided functional changes of human islets with regard to autophagy under glucolipotoxicity, and suggested modulation of autophagy as an anti-diabetic mechanism of PERKi.

Efficacy of local treatment for isolated liver metastasis after pancreatectomy in pancreatic ductal adenocarcinoma: A propensity score-matched analysis.

BACKGROUND: Although attempts of local treatment for isolated liver recurrence in patients with pancreatic ductal adenocarcinoma (PDAC) have increased, the efficacy remains unclear. Therefore, we aimed to evaluate the effect of local treatment for recurrent liver lesions after pancreatectomy on the survival of patients with PDAC. METHODS: Patients who were diagnosed with isolated liver recurrence after pancreatectomy at a high-volume center were included. We classified these patients based on the treatment options after recurrence and performed propensity score matching to minimize confounding. RESULTS: Median with interquartile range survival after recurrence was significantly longer for patients who underwent local treatment for recurrent liver lesions plus chemotherapy (22.0 [17.0-29.0] months) than those treated with chemotherapy alone (13.0 [7.0-21.0] months, p = .027). In multivariate analysis, not only local treatment for recurrent liver lesions plus chemotherapy (hazard ratio [95% confidence interval], 0.55 [0.32-0.94]; p = .030) but also indicators for systemically controlled tumor such as late recurrence (0.57 [0.35-0.92]; p = .021), chemotherapy for ≥6 months (0.25 [0.15-0.42]; p < .001), and disease control by chemotherapy (0.36 [0.22-0.60]; p < .001) were identified as favorable prognostic factors. CONCLUSIONS: PDAC patients with stable recurrent liver lesions should be considered a candidate for local treatment.

In Neoadjuvant FOLFIRINOX Chemotherapy for Pancreatic Ductal Adenocarcinoma, Which Response is the More Reliable Indicator for Prognosis, Radiologic or Biochemical?

BACKGROUND: In this era of increasing neoadjuvant chemotherapy, methods for evaluating responses to neoadjuvant chemotherapy are still diverse among institutions. Additionally, the efficacy of adjuvant chemotherapy for patients undergoing neoadjuvant chemotherapy remains unclear. Therefore, this retrospective study was performed to evaluate the effectiveness of methods for assessing response to neoadjuvant chemotherapy and the need for adjuvant chemotherapy in treating patients with non-metastatic pancreatic ductal adenocarcinoma. METHODS: The study identified 150 patients who underwent neoadjuvant FOLFIRINOX chemotherapy followed by curative-intent pancreatectomy. The patients were stratified by biochemical response based on the normalization of carbohydrate antigen 19-9 and by radiologic response based on size change at imaging. RESULTS: The patients were classified into the following three groups based on their response to neoadjuvant chemotherapy and prognosis: biochemical responders (BR+), radiology-only responders (BR-/RR+), and non-responders (BR-/RR-). The 3-year overall survival rate was higher for BR+ (71.0%) than for BR-/RR+ (53.6%) or BR-/RR- (33.1%) (P < 0.001). Response to neoadjuvant chemotherapy also was identified as a significant risk factor for recurrence in a comparison between BR-/RR+ and BR+ (hazard ratio [HR], 2.15; 95% confidence interval [CI] 1.19-3.88; P = 0.011) and BR-/RR- (HR, 3.82; 95% CI 2.41-6.08; P < 0.001). Additionally, regardless of the response to neoadjuvant chemotherapy, patients who completed adjuvant chemotherapy had a significantly higher 3-year overall survival rate than those who did not. CONCLUSIONS: This response evaluation criterion for neoadjuvant chemotherapy is feasible and can significantly predict prognosis. Additionally, completion of adjuvant chemotherapy could be helpful to patients who undergo neoadjuvant chemotherapy regardless of their response to neoadjuvant chemotherapy.

Inadequacy of the eighth edition of the American Joint Committee on Cancer pancreatic cancer staging system for invasive carcinoma associated with premalignant lesions in the pancreas: an analysis using the National Cancer Database.

BACKGROUND: Invasive carcinomas arising from premalignant lesions are currently staged by the same criteria as conventional pancreatic ductal adenocarcinoma. METHODS: Clinicopathologic information and survival data were extracted through a thorough search of histology codes from National Cancer Database (2006-2016). A total of 723 patients with invasive intraductal papillary mucinous neoplasm and mucinous cystic neoplasm were analyzed. RESULTS: The median age was 67 years, and 351 patients (48.5%) were male. There were 212 (29.3%), 232 (32.1%), 272 (37.6%), and 7 (1.0%) patients with T1, T2, T3, and T4 classification. Extrapancreatic extension (EPE) was present in 284 (39.3%). Age (HR = 1.504, 95% CI 1.196-1.891), R1 or R2 resection (HR = 1.585, 95% CI 1.175-2.140), and EPE (HR = 1.598, 95% CI 1.209-2.113) were independent prognostic factors for overall survival. Size criteria did not significantly affect survival. The median survival was 115.9 months for patients without EPE, compared to 34.2 months for those with EPE. EPE discriminated survival better than tumor size. DISCUSSION: The T classification of the eighth edition AJCC staging system is not adequate for invasive carcinomas associated with premalignant lesions of the pancreas. They merit a separate, dedicated staging system that uses appropriate prognostic factors.

Reconsidering the absence of extrapancreatic extension in T staging for pancreatic adenocarcinoma in the AJCC (8th ed) Staging Manual using the National Cancer Database.

PURPOSE: Although the concept of extrapancreatic extension (EPEx) was removed in the eighth edition of the American Joint Committee on Cancer pancreatic cancer staging system, several studies have supported the prognostic significance of EPEx. This study aimed to investigate the significance of EPEx in pancreatic ductal adenocarcinoma (PDAC) using the National Cancer Database (NCDB). METHODS: Data of patients who underwent resection for PDAC between 2006 and 2016 were extracted and analyzed from the NCDB. Cases arising from premalignant lesions, those with metastases, and those treated with neoadjuvant therapy were excluded. RESULTS: Among 37,634 patients, the median overall survival was 23 months and the 5-year survival rate was 22.7%. The EPEx prevalence was the lowest for T1 stage (63.2%) and increased with each T-stage (T2:83.4%, T3:85.8%). The overall survival was better in EPEx-negative patients than in EPEx-positive patients (median 33.7 vs. 21.5 months; p<0.001). When the T-stages were stratified by EPEx, EPEx-positive patients showed worse survival in all T-stages than EPEx-negative patients. Survival was comparable between T1 EPEx-positive and T2 or T3 EPEx-negative patients (p=0.088 and p=0.178, respectively). Furthermore, T2 and T3 EPEx-negative patients had similar survival to each other (p=0.877), and distinctly superior survival compared to T2 and T3 EPEx-positive patients (p<0.001). CONCLUSIONS: EPEx was an important prognostic factor in the overall cohort and in differentiating between T stages. This study strongly suggests that staging systems should reinstate EPEx and apply it to all T-stages, especially in T1, where EPEx was absent in 36% of patients.