cIAP1/2 Antagonism Induces Antigen-Specific T Cell-Dependent Immunity.

Checkpoint blockade immunotherapy has failed in pancreatic cancer and other poorly responsive tumor types in part due to inadequate T cell priming. Naive T cells can receive costimulation not only via CD28 but also through TNF superfamily receptors that signal via NF-κB. Antagonists of the ubiquitin ligases cellular inhibitor of apoptosis protein (cIAP)1/2, also called second mitochondria-derived activator of caspases (SMAC) mimetics, induce degradation of cIAP1/2 proteins, allowing for the accumulation of NIK and constitutive, ligand-independent activation of alternate NF-κB signaling that mimics costimulation in T cells. In tumor cells, cIAP1/2 antagonists can increase TNF production and TNF-mediated apoptosis; however, pancreatic cancer cells are resistant to cytokine-mediated apoptosis, even in the presence of cIAP1/2 antagonism. Dendritic cell activation is enhanced by cIAP1/2 antagonism in vitro, and intratumoral dendritic cells show higher expression of MHC class II in tumors from cIAP1/2 antagonism-treated mice. In this study, we use in vivo mouse models of syngeneic pancreatic cancer that generate endogenous T cell responses ranging from moderate to poor. Across multiple models, cIAP1/2 antagonism has pleiotropic beneficial effects on antitumor immunity, including direct effects on tumor-specific T cells leading to overall increased activation, increased control of tumor growth in vivo, synergy with multiple immunotherapy modalities, and immunologic memory. In contrast to checkpoint blockade, cIAP1/2 antagonism does not increase intratumoral T cell frequencies. Furthermore, we confirm our previous findings that even poorly immunogenic tumors with a paucity of T cells can experience T cell-dependent antitumor immunity, and we provide transcriptional clues into how these rare T cells coordinate downstream immune responses.

Who Do We Fail to Rescue after Pancreatoduodenectomy? Outcomes Among >4000 Procedures Expose Windows of Opportunity.

OBJECTIVE: Our investigation on in-hospital mortality after 4474 pancreatoduodenectomies aimed to identify time-dependent risks as well as windows of opportunity to rescue patients from complications. BACKGROUND: Pancreatoduodenectomy is generally considered a safe procedure with a 1-10% perioperative mortality based on complexity and surgical volume. Yet, patients are susceptible for life-threatening complications particularly with extended resections. Recognition of distinct vulnerabilities over time while patients recover is required to permit focused monitoring, sophisticated resource allocation, and greatest surgical safety. METHODS: Patients who deceased in-hospital after pancreatoduodenectomy between 2003-2021 were retrieved from the institutional pancreatectomy registry and analyzed in detail with respect to their postoperative course. RESULTS: Among 4474 pancreatoduodenectomies, 156 patients deceased in-hospital (3.5%). When assessing root causes of mortality, we observed 3 different clusters of complications which were postpancreatectomy-specific (47.4%), visceral vasculature-associated (25.6%), or cardiopulmonary in origin (23.7%). The median times of root cause onset in the 3 categories were postoperative day (POD) 9, POD 4.5 ( P =0.008) and POD 3 ( P <0.001), and medians of in-hospital mortality were POD 31, POD 18 ( P =0.009) and POD 8 ( P <0.001), respectively. Intervals between root cause onset and mortality varied with medians of 23 days, 11 days ( P =0.017), and 1 days ( P <0.001). The 3 categories were similarly distributed between different types of surgical complexity. CONCLUSION: Postpancreatectomy-specific complications prompt almost half of in-hospital mortalities after pancreatoduodenectomy, with rather long intervals for interventions to prevent failure to rescue. In contrast, visceral vasculature-related events and cardiopulmonary complications dominate early in-hospital mortalities with short intervals until mortality, demanding rigorous management of such events or preoperative conditioning. These data externally validate a previous high-volume initiative and highlight distinct windows of opportunity to optimize perioperative safety.

Natural History of the Remnant Pancreatic Duct after Pancreatoduodenectomy for Non-Invasive Intraductal Papillary Mucinous Neoplasm: Results from an International Consortium.

BACKGROUND: Little is known about the prognostic significance of pancreatic duct (PD) dilation following pancreatoduodenectomy for intraductal papillary mucinous neoplasms (IPMN). Although PD dilation is typically the hallmark radiographic feature of IPMN, other causes of PD dilation exist, including anastomotic stricture, pancreatitis, senescence, and postsurgical passive dilation. Therefore, PD dilation after pancreatoduodenectomy for IPMN represents a diagnostic and management dilemma. The purpose of this study was to evaluate the significance of PD dilation after pancreatoduodenectomy for noninvasive IPMN. METHODS: All patients who underwent pancreatoduodenectomy for noninvasive IPMN at nine pancreatic academic centers between 2013 and 2018 were included. Variables were entered prospectively into institutional databases and retrospectively reviewed for the purpose of this study. Dilation of the PD remnant was defined as a duct diameter of ≥5 mm, according to international guidelines. RESULTS: Four-hundred and eighty-one patients were included in this study. The mean age of the patients was 66 years (range 30-90). Patients were surveilled for a median of 4.5 (+/-2.3; max 10.6) years. During follow-up, 132 patients (27.4%) developed PD dilation in the remnant tissue after a median of 3.3 years. Multivariable analysis demonstrated that older age at the time of pancreatoduodenectomy (P=0.01) and longer surveillance duration (P=0.002) were predictors of PD dilation. Interestingly, neither the pathological IPMN subtype (branch-duct vs. main duct/mixed, P=0.96) nor the preoperative PD diameter (P=0.14) was associated with an increased risk of PD dilation in the remnant. During follow-up, IPMN recurrence was suspected in the remaining 72 patients (18.4%), solely because of ductal dilation on cross-sectional imaging in 97% (70/72). Completion pancreatectomy was performed in only 16 patients (3.3%), of whom only four (0.8%) had invasive carcinoma. Three of these four patients had high-grade dysplasia in the original pancreatoduodenectomy specimen, whereas only one had a low-grade dysplastic lesion initially. On multivariable analysis, no variable was predictive of IPMN recurrence in the remnant. CONCLUSIONS: New main duct dilation in the pancreatic remnant after pancreatoduodenectomy for IPMN is common, occurring in 27% of the patients. The duration of surveillance is the main factor associated with remnant PD dilation, suggesting that this is likely a physiologic phenomenon. Although recurrence of IPMN in the remnant is often suspected, only 0.8% of patients develop an invasive carcinoma in the pancreatic remnant requiring completion pancreatectomy.

Surveillance for Presumed BD-IPMN of the Pancreas: Stability, Size, and Age Identify Targets for Discontinuation.

BACKGROUND & AIMS: Currently, most patients with branch duct intraductal papillary mucinous neoplasms (BD-IPMN) are offered indefinite surveillance, resulting in health care costs with questionable benefits regarding cancer prevention. This study sought to identify patients in whom the risk of cancer is equivalent to an age-matched population, thereby justifying discontinuation of surveillance. METHODS: International multicenter study involving presumed BD-IPMN without worrisome features (WFs) or high-risk stigmata (HRS) at diagnosis who underwent surveillance. Clusters of individuals at risk for cancer development were defined according to cyst size and stability for at least 5 years, and age-matched controls were used for comparison using standardized incidence ratios (SIRs) for pancreatic cancer. RESULTS: Of 3844 patients with presumed BD-IPMN, 775 (20.2%) developed WFs and 68 (1.8%) HRS after a median surveillance of 53 (interquartile range 53) months. Some 164 patients (4.3%) underwent surgery. Of the overall cohort, 1617 patients (42%) remained stable without developing WFs or HRS for at least 5 years. In patients 75 years or older, the SIR was 1.12 (95% CI, 0.23-3.39), and in patients 65 years or older with stable lesions smaller than 15 mm in diameter after 5 years, the SIR was 0.95 (95% CI, 0.11-3.42). The all-cause mortality for patients who did not develop WFs or HRS for at least 5 years was 4.9% (n = 79), and the disease-specific mortality was 0.3% (n = 5). CONCLUSIONS: The risk of developing pancreatic malignancy in presumed BD-IPMN without WFs or HRS after 5 years of surveillance is comparable to that of the general population depending on cyst size and patient age. Surveillance discontinuation could be justified after 5 years of stability in patients older than 75 years with cysts <30 mm, and in patients 65 years or older who have cysts ≤15 mm.

Induction Chemotherapy with FOLFIRINOX for Locally Advanced Pancreatic Cancer: A Simple Scoring System to Predict Effect and Prognosis.

BACKGROUND: Effective chemotherapy (CTx) protocols as induction treatment provide increasing opportunities for surgical resection of locally advanced pancreatic cancer (LAPC). Although improved survival after resection of LAPC with CTx has been reported for selected patients, reliable recommendations on the indication for conversion surgery after induction treatment are currently lacking. We investigated the factors predictive of prognosis in resected LAPC after FOLFIRINOX. METHODS: Consecutive patients with LAPC undergoing curative resection after FOLFIRINOX between 2011 and 2018 were identified from a prospectively maintained database. Relevant clinical parameters and CT findings were examined. A scoring system was developed based on the ratio of hazard ratios for overall survival of all significant predictors. RESULTS: A total of 62 patients with LAPC who underwent oncologic resection after FOLFIRINOX were analyzed. Tumor shrinkage, tumor density, and postchemotherapy CA19-9 serum levels were independently associated with overall survival (multivariate analysis: HR = 0.31, 0.17, and 0.18, respectively). One, two, and two points were allocated to these three factors in the proposed scoring system, respectively. The median overall survival of patients with a score from 0 to 2 was significantly shorter than that of patients with a score from 3 to 5 (22.1 months vs. 53.2 months, P < 0.001). CONCLUSIONS: Tumor density is a novel predictive marker for the prognosis of patients with resected LAPC after FOLFIRINOX. A simple scoring model incorporating tumor density, the tumor shrinkage rate, and CA 19-9 levels identifies patients with a low score, who may be candidates for additional treatment.

A Combination of Biochemical and Pathological Parameters Improves Prediction of Postresection Survival After Preoperative Chemotherapy in Pancreatic Cancer: The PANAMA-score.

OBJECTIVE: To build a prognostic score for patients with primary chemotherapy undergoing surgery for pancreatic cancer based on pathological parameters and preoperative Carbohydrate antigen 19-9 (CA19-9) levels. BACKGROUND: Prognostic stratification after primary chemotherapy for pancreatic cancer is challenging and prediction models, such as the AJCC staging system, lack validation in the setting of preoperative chemotherapy. METHODS: Patients with primary chemotherapy resected at the Massachusetts General Hospital between 2007 and 2017 were analyzed. Tumor characteristics independently associated with overall survival were identified and weighted by Cox-proportional regression. The pancreatic neoadjuvant Massachusetts-score (PANAMA-score) was computed from these variables and its performance assessed by Harrel concordance index and area under the receiving characteristics curves analysis. Comparisons were made with the AJCC staging system and external validation was performed in an independent cohort with primary chemotherapy from Heidelberg, Germany. RESULTS: A total of 216 patients constituted the training cohort. The multivariate analysis demonstrated tumor size, number of positive lymph-nodes, R-status, and high CA19-9 to be independently associated with overall survival. Kaplan-Meier analysis according to low, intermediate, and high PANAMA-score showed good discriminatory power of the new metrics (P < 0.001). The median overall survival for the three risk-groups was 45, 27, and 12 months, respectively. External validation in 258 patients confirmed the prognostic ability of the score and demonstrated better accuracy compared with the AJCC staging system. CONCLUSION: The proposed PANAMA-score, based on independent predictors of postresection survival, including pathologic variables and CA19-9, not only provides better discrimination compared to the AJCC staging system, but also identifies patients at high-risk for early death.

Systematic Review and Metaanalysis of Lymph Node Metastases of Resected Pancreatic Neuroendocrine Tumors.

BACKGROUND: The optimal surgical strategy for pancreatic neuroendocrine tumors (PNETs) is unknown. However, current guidelines recommend a watch-and-wait strategy for small nonfunctional PNETs (NF-PNETs). The aim of this study is to investigate the risk stratification and prognostic significance of lymph node metastasis (LNM) of PNETs to guide decision-making for lymphadenectomy. PATIENTS AND METHODS: The MEDLINE and Web of Science databases were systematically searched for studies reporting either risk factors of LNM in resected PNETs or survival of patients with LNM. The weighted average incidence of LNM was calculated according to tumor characteristics. Random-effects metaanalyses were performed, and pooled hazard ratios (HR) and their 95% confidence intervals (CI) were calculated to determine the impact of LNM on overall survival (OS). In subgroup analyses, NF-PNETs were assessed. RESULTS: From a total of 5883 articles, 98 retrospective studies with 13,374 patients undergoing resection for PNET were included. In all PNETs, the weighted median rates of LNM were 11.5% for small (≤ 2 cm) PNETs and 15.8% for G1 PNETs. In NF-PNETs, the rates were 11.2% for small PNETs and 10.3% for G1 PNETs. LNM of all PNETs (HR 3.87, 95% CI 3.00-4.99, P < 0.001) and NF-PNETs (HR 4.98, 95% CI 2.81-8.83, P < 0.001) was associated with worse OS. CONCLUSIONS: LNM is potentially prevalent even in small and well-differentiated PNETs and is associated with worse prognosis. A watch-and-wait strategy for small NF-PNETs should be reappraised, and oncologic resection with lymphadenectomy can be considered. Prospective and controlled studies are needed in the future.

Severe acute pancreatitis: surgical indications and treatment.

BACKGROUND: Acute pancreatitis (AP) is defined as an acute inflammatory attack of the pancreas of sudden onset. Around 25% of patients have either moderately severe or severe disease with a mortality rate of 15-20%. PURPOSE: The aim of this article was to summarize the advances being made in the understanding of this disease and the important role of surgery. RESULTS AND CONCLUSIONS: An accurate diagnosis should be made a soon as possible, initiating resuscitation with large volume intravenous fluids and oxygen by mask. Predicted severe disease will require intensive monitoring. Most deaths within the first week are due to multi-organ failure; thus, these patients will require intensive therapy unit management. During the second phase of the disease, death is due to local complications arising from the pancreatic inflammation, requiring accurate identification to determine the correct form of treatment. Acute peripancreatic fluid collections arise < 4 weeks after onset of interstitial edematous pancreatitis, not requiring any treatment. Most pancreatic pseudocysts arise > 4 weeks and largely resolve on conservative management. Necrotizing pancreatitis causing acute necrotic collections and later walled-off necrosis will require treatment if symptomatic or infected. Initial endoscopic transgastric or percutaneous drainage will resolve less serious collections but necrosectomy using minimally invasive approaches will be needed for more serious collections. To prevent recurrent attacks of AP, causative factors need to be removed where possible such as cholecystectomy and cessation of alcohol. Future progress requires improved management of multi-organ failure and more effective minimally invasive techniques for the removal of necrosis.

Expression of Angiogenic Proteins in Tumor and Stroma Affects Survival in Patients With Gastric Cancer.

BACKGROUND: Gastric cancer is one of the most frequent malignancies worldwide. Angiogenic growth factors play a crucial role in mediating the crosstalk between cancer cells and the surrounding microenvironment. In this exploratory study, we investigate the impact of angiogenic proteins within the tumor cell or stroma compartment on survival of patients with gastric cancer. MATERIALS AND METHODS: In 29 patients, tumor and stromal compartments were separated using laser capture microdissection. Angiogenic protein expression was measured using a bead-based immunoassay and correlated with tumor stage and overall survival. RESULTS: Overall survival was significantly shorter in patients with a high stroma concentration of vascular endothelial growth factor (VEGF)-A (23.5 (±17.6) versus 33.6 (±21.0) mo; P = 0.009) and stem cell factor (22.2 (±18.5) versus 33.6 (±21.8) mo; P = 0.01) compared with patients with a low stroma concentration. High stromal VEGF-D showed a trend toward worse survival (26.8 (±22.0) versus 37.2 (±19.0) mo; P = 0.09). We did not observe any significant correlation between tumor-specific expression of angiogenic cytokines and survival. CONCLUSIONS: This translational study highlights the difference in clinical impact between tumor and stromal expression of angiogenic proteins. Compartment-specific concentrations of VEGF-A and stem cell factor affect the clinical prognosis and help to identify the best therapy for patients with gastric cancer.

Systematic review and meta-analysis of contemporary pancreas surgery with arterial resection.

OBJECTIVE: Advances in multimodality treatment paralleled increasing numbers of complex pancreatic procedures with major vascular resections. The aim of this meta-analysis was to evaluate the current outcomes of arterial resection (AR) in pancreatic surgery. METHODS: A systematic literature search was carried out from January 2011 until January 2020. MOOSE guidelines were followed. Predefined outcomes were morbidity, pancreatic fistula, postoperative bleeding and delayed gastric emptying, reoperation rate, mortality, hospital stay, R0 resection rate, and lymph node positivity. Duration of surgery, blood loss, and survival were also analyzed. RESULTS: Eight hundred and forty-one AR patients were identified in a cohort of 7111 patients. Morbidity and mortality rates in these patients were 66.8% and 5.3%, respectively. Seven studies (579 AR patients) were included in the meta-analysis. Overall morbidity (48% vs 39%, p = 0.1) and mortality (3.2% vs 1.5%, p = 0.27) were not significantly different in the groups with or without AR. R0 was less frequent in the AR group, both in patients without (69% vs 89%, p < 0.001) and with neoadjuvant treatment (50% vs 86%, p < 0.001). Weighted median survival was shorter in the AR group (18.6 vs 32 months, range 14.8-43.1 months, p = 0.037). CONCLUSIONS: Arterial resections increase the complexity of pancreatic surgery, as demonstrated by relevant morbidity and mortality rates. Careful patient selection and multidisciplinary planning remain important.

Cytologic Analysis of Pancreatic Juice Increases Specificity of Detection of Malignant IPMN-A Systematic Review.

BACKGROUND & AIMS: Intraductal papillary mucinous neoplasms (IPMNs) of the pancreas can progress to cancer. Biomarkers have been identified that were reported to increase the accuracy of identification of malignant lesions; we performed a systematic review of the accuracy of these markers. METHODS: We performed a systematic review of published studies on biomarkers of malignant IPMNs by searching MEDLINE and Web of Science databases from January 2005 through December 2017. Our methods were developed based on the Meta-analysis Of Observational Studies in Epidemiology guidelines. Pooled sensitivity, specificity, receiver operating characteristic curves, and their respective areas under the curve (AUC) were calculated from groups of markers (cell-, protein-, or DNA-based) measured in samples collected before and after surgery. A hypothetical test model was developed to determine how to meaningfully amend the revised Fukuoka guidelines, focusing on increasing test specificity for patients with IPMNs that have worrisome features. RESULTS: We collected data from 193 published studies, comprising 12,297 patients, that analyzed 7 preoperative and 21 postoperative markers of IPMNs. The 3 biomarkers that identified malignant IPMNs with the largest AUC values were pancreatic juice cytology (AUC, 0.84; sensitivity, 0.54; specificity, 0.91), serum protein carbohydrate antigen 19-9 (AUC, 0.81; sensitivity, 0.45; specificity, 0.90), and cyst fluid cytology (AUC, 0.82; sensitivity, 0.57; specificity, 0.84). A combination of cytologic and immunohistochemical analysis of MUC1 and MUC2 in pancreatic juice samples identified malignant IPMNs with the largest AUC and sensitivity values (AUC, 0.85; sensitivity, 0.85; specificity, 0.65). In a test model, inclusion of cytologic analysis of pancreatic juice in the guideline algorithm significantly increased the specificity of detection of malignant IPMNs. CONCLUSIONS: In a systematic review, we found cytologic analysis of pancreatic juice to have the greatest effect in increasing the specificity of detection of malignant IPMNs. We propose addition of this test to the Fukuoka guidelines for assessment of patients with IPMNs with worrisome features.

Definition of an extended minimum level of lymphadenectomy in non-pancreatic periampullary cancer resections.

BACKGROUND: The number of lymph nodes to be resected in surgery for non-pancreatic periampullary cancer remains unclear. METHODS: The Surveillance, Epidemiology, and End Results (SEER) database was used to gather information from a large retrospective cohort. To define a novel, reasonable cut-off associated with survival, we stratified patients into subgroups depending on the number of resected lymph nodes. RESULTS: 1481 nodal-negative patients resected for periampullary cancer (excluding pancreatic ductal adenocarcinoma) were included. The median number of resected lymph nodes was ten. Median overall survival in the subgroup with less than 10 removed lymph nodes was 40 months, while median survival for patients with ≥10 lymph nodes was 97 months (p < 0.001). A significant survival benefit was seen if ≥ 16 lymph nodes were harvested (median survival, 117 months), while no further benefit was observed if more than 21 nodes were removed (median survival, >120 months). CONCLUSION: Sixteen or more resected lymph nodes are associated with improved survival in node-negative periampullary carcinoma. We propose to aim at harvesting and analyzing at least 16 lymph nodes.

The nitric oxide donor JS-K sensitizes U87 glioma cells to repetitive irradiation.

As a potent radiosensitizer nitric oxide (NO) may be a putative adjuvant in the treatment of malignant gliomas which are known for their radio- and chemoresistance. The NO donor prodrug JS-K (O2-(2.4-dinitrophenyl) 1-[(4-ethoxycarbonyl) piperazin-1-yl] diazen-1-ium-1,2-diolate) allows cell-type specific intracellular NO release via enzymatic activation by glutathione-S-transferases overexpressed in glioblastoma multiforme. The cytotoxic and radiosensitizing efficacy of JS-K was assessed in U87 glioma cells in vitro focusing on cell proliferation, induction of DNA damage, and cell death. In vivo efficacy of JS-K and repetitive irradiation were investigated in an orthotopic U87 xenograft model in mice. For the first time, we could show that JS-K acts as a potent cytotoxic and radiosensitizing agent in U87 cells in vitro. This dose- and time-dependent effect is due to an enhanced induction of DNA double-strand breaks leading to mitotic catastrophe as the dominant form of cell death. However, this potent cytotoxic and radiosensitizing effect could not be confirmed in an intracranial U87 xenograft model, possibly due to insufficient delivery into the brain. Although NO donor treatment was well tolerated, neither a retardation of tumor growth nor an extended survival could be observed after JS-K and/or radiotherapy.

The Sendai and Fukuoka consensus criteria for the management of branch duct IPMN - A meta-analysis on their accuracy.

INTRODUCTION: The risk of malignancy in branch duct intraductal papillary mucinous neoplasia of the pancreas (BD-IPMN) is controversially debated. An increasing number of studies report on outcomes using the Sendai or Fukuoka consensus criteria for treatment decision-making. The objective of this work was to evaluate the diagnostic accuracy of the Sendai and Fukuoka criteria. METHODS: We systematically reviewed studies on Sendai or Fukuoka criteria-guided management of BD-IPMN. Pooled sensitivity, specificity and diagnostic odds ratios as compound measures of diagnostic accuracy were calculated from studies matching the inclusion criteria. The meta-analysis was performed using a random effects model. RESULTS: Fifteen studies with a total of 2710 patients were included. Twelve of these used the Sendai criteria. In these studies, 23% of Sendai-negative patients had a high grade dysplastic lesion or an invasive carcinoma in final histology. Pooled sensitivity was 56%, specificity was 74% and the diagnostic odds ratio for malignancy in Sendai-positive lesions was 7.45. When the results of follow-up examinations were included, diagnostic accuracy improved significantly (14.66, p < 0.001). Three studies were identified that used the Fukuoka criteria for decision making. Of 200 patients with Fukuoka-negative lesions who underwent surgery, 22 had a malignant lesion in final histology (11%). Pooled sensitivity was 83%, specificity was 53% and the diagnostic odds ratio was 8.76. CONCLUSION: The Fukuoka criteria have considerably improved sensitivity but still lack adequate specificity. For further reduction of a potential surgical overtreatment of BD-IPMN, the development of criteria with an increased specificity is required.

Thrombosis and anticoagulation after portal vein reconstruction during pancreatic surgery - A systematic review.

OBJECTIVE: To comprehensively assess thrombotic events and their clinical impact in patients receiving pancreatic surgery with venous resection and reconstruction. BACKGROUND: Portal vein (PV, including the portal vein and superior mesenteric vein) resection and reconstruction enables surgical removal of borderline-resectable and locally advanced pancreatic cancer. Thrombosis of the reconstructed PV represents a major source of early postoperative and long-term morbidity and mortality. No universally accepted standard for anticoagulation exists. Here, we aimed to assess early and late thrombosis rates after PV reconstruction with special regard to type of PV reconstruction as well as anticoagulation regimen. METHODS: PRISMA guidelines were followed. Studies reporting on PV resection and reconstruction providing data on thrombosis rates were included. The following parameters were assessed: Study type, year of publication, number of patients, type/number of PV reconstruction, follow-up period, postoperative mortality, rate of thrombosis of reconstructed PV axis, intraoperative blood loss, and anticoagulation. RESULTS: 23 studies with 2751 patients were included in the final analysis. 670 patients received tangential resection of the PV with venorrhaphy or patch repair, 1505 patients had segmental resection with end-to-end reconstruction, and 576 patients received reconstruction with an interposition graft/conduit. The pooled overall thrombosis rate was 15%. Reconstruction of tangential defects with either venorrhaphy or patch repair as well as end-to-end repair of segmental defects resulted in a thrombosis rate of 12%. Subgroup analysis according to the type of graft reconstruction revealed the highest occlusion rates of 55% in patients with allogeneic grafts, followed by up to 27% in patients with synthetic PV conduits. Autologous conduits had a thrombosis rate of 10%. Early thrombotic events were detected in 5% of patients after venorrhaphy/patch reconstruction and end-to-end reconstruction. Early events were most common in the allogeneic graft subgroup (22%), followed by synthetic conduits (15%). There were fewer early events in the autologous graft group (7%). Early PV thrombosis was associated with relevant mortality of up to 26%. Anticoagulation regimens varied between studies. CONCLUSION: The overall rate of thrombosis after portal vein resection is low. However, among different reconstruction techniques, allogeneic interposition grafts/conduits had the highest thrombosis rates among the different types of reconstruction after PV resection. No specific anticoagulation strategy can be considered beneficial on the basis of the existing literature. MINI-ABSTRACT: Thrombosis of the reconstructed portal vein (PV) after PV resection in pancreatic surgery represents a relevant source of major morbidity and mortality. In this systematic review, while we observed an overall low thrombosis rate following PV resection, reconstruction with allogeneic grafts harbors the highest risk of postoperative thrombosis. Early thrombosis was most common after reconstruction with allogeneic grafts and associated with postoperative mortality. Anticoagulation strategies vary greatly among different studies.

Carbapenem Antibiotics Versus Other Antibiotics for Complicated Intra-abdominal Infections: a Systematic Review and Patient-Level Meta-analysis of Randomized Controlled Trials (PROSPERO CRD42018108854).

BACKGROUND: The treatment of complicated intra-abdominal infections remains a challenge. Both optimal medical and surgical therapy (i.e., source control) are needed to achieve low mortality and morbidity. The objective of this systematic review and meta-analysis is to determine the impact of carbapenem antibiotic therapy compared to other antibiotics in complicated intra-abdominal infections (secondary peritonitis) with an emphasis on mortality and postoperative complications. METHODS: A systematic literature search from PubMed/Medline and Web of Science databases was carried out. The last search was conducted in August 2022. PRISMA guidelines were followed. Pre-defined outcomes were mortality, treatment success, treatment failure, and adverse events. RESULTS: Ten randomized controlled trials, published from 1983 to 2013 with a total of 2377 patients (1255 patients in the carbapenem antibiotics group and 1122 in the control group), were identified. A meta-analysis comparing patients undergoing carbapenem antibiotic therapy and patients receiving other antibiotics was performed. No significant difference regarding mortality (OR 1.19, 95% CI [0.79; 1.82], p = 0.40), treatment success (OR 1.17, 95% CI [0.72; 1.91], p = 0.53), and treatment failure (OR 0.84, 95% CI [0.48; 1.45], p = 0.52) was observed. Carbapenem therapy was associated with fewer adverse events compared to therapy with other antibiotics (OR 0.79, 95% CI [0.65; 0.97], p = 0.022). CONCLUSION: There is currently no evidence that carbapenem antibiotics are superior in terms of mortality, and success or failure for the treatment of complicated intra-abdominal infections (secondary peritonitis). The rate of adverse events is lower under carbapenem therapy compared to control antibiotics. TRIAL REGISTRATION: PROSPERO 2018 CRD42018108854.

Surgery for intraductal papillary mucinous neoplasms in young patients: High-risk population.

BACKGROUND: Intraductal papillary mucinous neoplasms of the pancreas are uncommon in young individuals. Management of these patients is challenging because the risk of malignancy and recurrence after surgery remains unclear. The aim of the present study was to assess the long-term risk for intraductal papillary mucinous neoplasm recurrence after surgery for intraductal papillary mucinous neoplasms in patients ≤50 years of age. METHODS: Perioperative and long-term follow-up data of patients who had undergone surgery for intraductal papillary mucinous neoplasms between 2004 and 2020 were extracted from a prospective unicentric database and retrospectively analyzed. RESULTS: Seventy-eight patients underwent surgical treatment for benign intraductal papillary mucinous neoplasms (low-grade n = 22 and intermediate-grade n = 21) and malignant intraductal papillary mucinous neoplasms (high-grade n = 16 and intraductal papillary mucinous neoplasm-associated carcinoma n = 19). Severe postoperative morbidity (Clavien-Dindo ≥III) was found in 14 patients (18%). The median length of hospital stay was 10 days. No perioperative mortality was observed. The median length of follow-up was 72 months. Recurrence of intraductal papillary mucinous neoplasm-associated carcinoma was found in 6 patients (19%) with malignant intraductal papillary mucinous neoplasm and 1 patient (3%) with benign intraductal papillary mucinous neoplasm. CONCLUSION: Surgery for intraductal papillary mucinous neoplasm is safe and can be performed with low morbidity and potentially no mortality in young patients. Given the high rate of malignancy (45%), these patients with intraductal papillary mucinous neoplasms represent a high-risk population, and prophylactic surgical treatment should be considered in these patients with long life expectancies. Regular clinical and radiologic follow-up examinations are important to rule out disease recurrence, which is high, especially in patients with intraductal papillary mucinous neoplasm-associated carcinoma.