Multivariate logistic regression analysis for prediction of clinically relevant pancreatic fistula in the early phase after pancreaticoduodenectomy

Risk stratification of postoperative pancreatic fistula and other complications following pancreatoduodenectomy. How far are we? A scoping review

PURPOSE

Pancreatoduodenectomy (PD) is a challenging procedure which is associated with high morbidity rates. This study was performed to make an overview of risk factors included in risk stratification methods both logistic regression models and models based on artificial intelligence algorithms to predict postoperative pancreatic fistula (POPF) and other complications following PD and to provide insight in the extent to which these tools were validated.

METHODS

Five databases were searched to identify relevant studies. Calculators, equations, nomograms, and artificial intelligence models that addressed POPF and other complications were included. Only PD resections were considered eligible. There was no exclusion of the minimally invasive techniques reporting PD resections. All other pancreatic resections were excluded.

RESULTS

90 studies were included. Thirty-five studies were related to POPF, thirty-five studies were related to other complications following PD and twenty studies were related to artificial intelligence predication models after PD. Among the identified risk factors, the most used factors for POPF risk stratification were the main pancreatic duct diameter (MPD) (80%) followed by pancreatic texture (51%), whereas for other complications the most used factors were age (34%) and ASA score (29.4%). Only 26% of the evaluated risk stratification tools for POPF and other complications were externally validated. This percentage was even lower for the risk models using artificial intelligence which was 20%.

CONCLUSION

The MPD was the most used factor when stratifying the risk of POPF followed by pancreatic texture. Age and ASA score were the most used factors for the stratification of other complications. Insight in clinically relevant risk factors could help surgeons in adapting their surgical strategy and shared decision-making. This study revealed that the focus of research still lies on developing new risk models rather than model validation, hampering clinical implementation of these tools for decision support.

Risk Models for Developing Pancreatic Fistula After Pancreatoduodenectomy: Validation in a Nationwide Prospective Cohort

OBJECTIVE

To evaluate the performance of published fistula risk models by external validation, and to identify independent risk factors for postoperative pancreatic fistula (POPF).

BACKGROUND

Multiple risk models have been developed to predict POPF after pancreatoduodenectomy. External validation in high-quality prospective cohorts is, however, lacking or only performed for individual models.

METHODS

A post hoc analysis of data from the stepped-wedge cluster cluster-randomized Care After Pancreatic Resection According to an Algorithm for Early Detection and Minimally Invasive Management of Pancreatic Fistula versus Current Practice (PORSCH) trial was performed. Included were all patients undergoing pancreatoduodenectomy in the Netherlands (January 2018-November 2019). Risk models on POPF were identified by a systematic literature search. Model performance was evaluated by calculating the area under the receiver operating curves (AUC) and calibration plots. Multivariable logistic regression was performed to identify independent risk factors associated with clinically relevant POPF.

RESULTS

Overall, 1358 patients undergoing pancreatoduodenectomy were included, of whom 341 patients (25%) developed clinically relevant POPF. Fourteen risk models for POPF were evaluated, with AUCs ranging from 0.62 to 0.70. The updated alternative fistula risk score had an AUC of 0.70 (95% confidence intervals [CI]: 0.69-0.72). The alternative fistula risk score demonstrated an AUC of 0.70 (95% CI: 0.689-0.71), whilst an AUC of 0.70 (95% CI: 0.699-0.71) was also found for the model by Petrova and colleagues. Soft pancreatic texture, pathology other than pancreatic ductal adenocarcinoma or chronic pancreatitis, small pancreatic duct diameter, higher body mass index, minimally invasive resection and male sex were identified as independent predictors of POPF.

CONCLUSION

Published risk models predicting clinically relevant POPF after pancreatoduodenectomy have a moderate predictive accuracy. Their clinical applicability to identify high-risk patients and guide treatment strategies is therefore questionable.

A Machine Learning Approach to Predict Postoperative Pancreatic Fistula After Pancreaticoduodenectomy Using Only Preoperatively Known Data

BACKGROUND

Clinically-relevant postoperative pancreatic fistula (CR-POPF) following pancreaticoduodenectomy (PD) is a major postoperative complication and the primary determinant of surgical outcomes. However, the majority of current risk calculators utilize intraoperative and postoperative variables, limiting their utility in the preoperative setting. Therefore, we aimed to develop a user-friendly risk calculator to predict CR-POPF following PD using state-of-the-art machine learning (ML) algorithms and only preoperatively known variables.

METHODS

Adult patients undergoing elective PD for non-metastatic pancreatic cancer were identified from the ACS-NSQIP targeted pancreatectomy dataset (2014-2019). The primary endpoint was development of CR-POPF (grade B or C). Secondary endpoints included discharge to facility, 30-day mortality, and a composite of overall and significant complications. Four models (logistic regression, neural network, random forest, and XGBoost) were trained, validated and a user-friendly risk calculator was then developed.

RESULTS

Of the 8666 patients who underwent elective PD, 13% (n = 1160) developed CR-POPF. XGBoost was the best performing model (AUC = 0.72), and the top five preoperative variables associated with CR-POPF were non-adenocarcinoma histology, lack of neoadjuvant chemotherapy, pancreatic duct size less than 3 mm, higher BMI, and higher preoperative serum creatinine. Model performance for 30-day mortality, discharge to a facility, and overall and significant complications ranged from AUC 0.62-0.78.

CONCLUSIONS

In this study, we developed and validated an ML model using only preoperatively known variables to predict CR-POPF following PD. The risk calculator can be used in the preoperative setting to inform clinical decision-making and patient counseling.

Drain fluid biomarkers for the diagnosis of clinically relevant postoperative pancreatic fistula: a diagnostic accuracy systematic review and meta-analysis

BACKGROUND

Pancreatectomy is the only curative treatment available for pancreatic cancer and a necessity for patients with challenging pancreatic pathology. To optimize outcomes, postsurgical complications such as clinically relevant postoperative pancreatic fistula (CR-POPF) should be minimized. Central to this is the ability to predict and diagnose CR-POPF, potentially through drain fluid biomarkers. This study aimed to assess the utility of drain fluid biomarkers for predicting CR-POPF by conducting a diagnostic test accuracy systematic review and meta-analysis.

METHODS

Five databases were searched for relevant and original papers published from January 2000 to December 2021, with citation chaining capturing additional studies. The QUADAS-2 tool was used to assess the risk of bias and concerns regarding applicability of the selected studies.

RESULTS

Seventy-eight papers were included in the meta-analysis, encompassing six drain biomarkers and 30 758 patients with a CR-POPF prevalence of 17.42%. The pooled sensitivity and specificity for 15 cut-offs were determined. Potential triage tests (negative predictive value >90%) were identified for the ruling out of CR-POPF and included postoperative day 1 (POD1) drain amylase in pancreatoduodenectomy (PD) patients (300 U/l) and in mixed surgical cohorts (2500 U/l), POD3 drain amylase in PD patients (1000-1010 U/l) and drain lipase in mixed surgery groups (180 U/l). Notably, drain POD3 lipase had a higher sensitivity than POD3 amylase, while POD3 amylase had a higher specificity than POD1.

CONCLUSIONS

The current findings using the pooled cut-offs will offer options for clinicians seeking to identify patients for quicker recovery. Improving the reporting of future diagnostic test studies will further clarify the diagnostic utility of drain fluid biomarkers, facilitating their inclusion in multivariable risk-stratification models and the improvement of pancreatectomy outcomes.

Drain fluid biomarkers for prediction and diagnosis of clinically relevant postoperative pancreatic fistula: A narrative review

Clinically relevant postoperative pancreatic fistula (CR-POPF) has continued to compromise patient recovery post-pancreatectomy despite decades of research seeking to improve risk prediction and diagnosis. The current diagnostic criteria for CR-POPF requires elevated drain fluid amylase to present alongside POPF-related complications including infection, haemorrhage and organ failure. These worrying sequelae necessitate earlier and easily obtainable biomarkers capable of reflecting evolving CR-POPF. Drain fluid has recently emerged as a promising source of biomarkers as it is derived from the pancreas and hence, capable of reflecting its postoperative condition. The present review aims to summarise the current knowledge of CR-POPF drain fluid biomarkers and identify gaps in the field to invigorate future research in this critical area of clinical need. These findings may provide robust diagnostic alternatives for CR-POPF and hence, to clarify their clinical utility require further reports detailing their diagnostic and/or predictive accuracy.

Pyroptosis-Related Gene Signature and Expression Patterns in the Deterioration of Atherosclerosis

Background

Pyroptosis has been shown to be involved in the overall process of atherosclerosis. This study was aimed at investigating pyroptosis-related gene expression patterns in atherosclerosis and their diagnostic significance.

Methods and Results

In GSE100927, fifty-four pyroptosis-related genes were identified. Between atherosclerotic plaques and normal samples, the expression patterns of pyroptosis-related genes were significantly different. In order to construct a pyroptosis-related risk score signature (PRSS), the least absolute shrinkage and selection operator (LASSO) was combined with multivariate logistic regression to screen twelve genes. The diagnostic efficiency of the PRSS performed well in GSE43292, as shown by the results of receiver-operating characteristics (ROCs). Consensus clustering identified two expression patterns of pyroptosis-related genes in different statuses of atherosclerotic plaque in GSE163154. The biological behavior of the different clusters was examined by the gene set variation analysis (GSVA). The Kyoto Encyclopedia of Genes and Genomes (KEGG) and Gene Ontology (GO) enrichment analyses revealed that the differentially expressed genes (DEGs) in the two clusters were enriched in the immune response. The Cytoscape software was used to construct protein-protein interaction (PPI) networks for hub gene screening. Following that, the Drug Gene Interaction Database (DGIdb) was utilized to find 47 possible medicines and chemical compounds that interact with hub genes in atherosclerotic plaques.

Conclusion

The results of this study showed that pyroptosis-related genes contribute to the progression of atherosclerosis and may serve as biomarkers in clinical diagnosis as well as novel therapeutic targets for the treatment of AS.

External validation of postoperative pancreatic fistula prediction scores in pancreatoduodenectomy: a systematic review and meta-analysis

BACKGROUND

Multiple risk scores claim to predict the probability of postoperative pancreatic fistula (POPF) after pancreatoduodenectomy. It is unclear which scores have undergone external validation and are the most accurate. The aim of this study was to identify risk scores for POPF, and assess the clinical validity of these scores.

METHODS

Areas under receiving operator characteristic curve (AUROCs) were extracted from studies that performed external validation of POPF risk scores. These were pooled for each risk score, using intercept-only random-effects meta-regression models.

RESULTS

Systematic review identified 34 risk scores, of which six had been subjected to external validation, and so included in the meta-analysis, (Tokyo (N=2 validation studies), Birmingham (N=5), FRS (N=19), a-FRS (N=12), m-FRS (N=3) and ua-FRS (N=3) scores). Overall predictive accuracies were similar for all six scores, with pooled AUROCs of 0.61, 0.70, 0.71, 0.70, 0.70 and 0.72, respectively. Considerably heterogeneity was observed, with I2 statistics ranging from 52.1-88.6%.

CONCLUSION

Most risk scores lack external validation; where this was performed, risk scores were found to have limited predictive accuracy. . Consensus is needed for which score to use in clinical practice. Due to the limited predictive accuracy, future studies to derive a more accurate risk score are warranted.

Diagnostic value of C-reactive protein and procalcitonin for postoperative pancreatic fistula following pancreatoduodenectomy: a systematic review and meta-analysis

BACKGROUND

C-reactive protein (CRP) and procalcitonin (PCT) have recently been used to diagnose and screen for postoperative pancreatic fistula (POPF) following pancreatoduodenectomy (PD), but their reliability is still unclear. Our study aims to assess the efficacy of CRP and PCT in the diagnosis of POPF after PD.

METHODS

Electronic databases such as PubMed, Excerpta Medica (EMBASE), the Web of Science (WOS) and the China National Knowledge Infrastructure (CNKI) were used to search for studies and full-text articles that assessed the diagnostic efficacy of CRP and PCT for POPF. Review Manager 5.4 and STATA 14.0 were used to estimate the pooled diagnostic value of CRP and PCT. Sensitivity analyses and Deeks' funnel plot tests were conducted on the selected studies.

RESULTS

Twenty studies that satisfied the established selection criteria were chosen. Both CRP and PCT were shown to be highly effective in diagnosing POPF, each with a high area under the curve (AUC). The AUC of CRP on postoperative day (POD) 4 had a value of 0.86, with a sensitivity and specificity of 0.85 and 0.69, respectively. The AUC of PCT on POD 5 had a value of 0.87, with a sensitivity and specificity of 0.84 and 0.74, respectively.

DISCUSSION

Our research supports the hypothesis that CRP and PCT are valuable diagnostic tools for predicting POPF, especially given the CRP levels on POD 4 and PCT levels on POD 5. Limited by the small number of the studies analyzed herein, we recommend that more randomized controlled trials be performed to verify our conclusions.

Establishment of risk prediction model of postoperative pancreatic fistula after pancreatoduodenectomy: 2016 edition of definition and grading system of pancreatic fistula: a single center experience with 223 cases

Objective

To establish a risk prediction model for pancreatic fistula according to the pancreatic fistula standards of the 2016 edition.

Methods

Clinical data from 223 patients with PD admitted to Tianjin Third Central Hospital from January 2016 to December 2020 were retrospectively analyzed. Patients were divided into modeling (January 2016 to December 2018) and validation (January 2019 to December 2020) sets according to the time of admission. The risk factors for postoperative pancreatic fistula (POPF) were screened by univariate and multivariate logistic regression analyses, and a risk prediction model for POPF was established in the modeling set. This score was tested in the validation set.

Results

Logistic regression analysis showed that the main pancreatic duct index and CT value were independent risk factors according to the 2016 pancreatic fistula grading standard, based on which a risk prediction model for POPF was established. Receiver operating characteristic curve analysis showed that the area under the curve was 0.775 in the modeling set and 0.848 in the validation set.

Conclusion

The main pancreatic duct index and CT value of the pancreas are closely related to the occurrence of pancreatic fistula after PD, and the established risk prediction model for pancreatic fistula has good prediction accuracy.

Nomogram based on albumin and neutrophil-to-lymphocyte ratio for predicting postoperative complications after pancreaticoduodenectomy

Background

The aim of this study was to identify a preoperative inflammatory marker with the most predictive value for postoperative complications after pancreaticoduodenectomy (PD). We then combined it with other perioperative variables to construct and validate a nomogram for complications after PD.

Methods

A total of 223 patients who received PD from January 2014 to July 2019 at a high-volume (>60 PDs/year) pancreatic centers in China were included in this retrospective study. All of the PDs were performed by the same surgeon who is beyond the learning curve with more than 100 PDs over the previous 3 years before 2014. 15 preoperative inflammatory markers were collected, including neutrophils, lymphocytes, high-sensitivity C-reactive protein and lactic dehydrogenase. The inflammatory markers' predicting abilities for complications were analyzed by calculating the values of an area under the curve (AUC). The complications included surgical complications (such as pancreatic fistula, delayed gastric emptying and bile leakage) and medical complications (such as sepsis, pneumonia, urinary tract infection, acute heart failure and acute liver failure) in this study. Univariable and multivariable logistic regression analyses were performed to investigate the perioperative features for independent risk factors for complications after PD. Nomograms with or without the most predictive inflammatory for complications were subsequently developed based on multivariable logistic regression using Akaike information criterion. Nomograms' performance was quantified and compared in terms of calibration and discrimination. We studied the utility of the nomograms using decision curve analysis.

Results

The albumin/ NLR score (ANS) exhibited the highest AUC value (0.616) for predicting postoperative complications. ANS and approach method were identified as independent risk factors for complications. The nomogram with ANS had higher C-index (0.725) and better calibration. The NRI compared between nomograms was 0.160 (95% CI: 0.023-0.296; P=0.022). By decision curve analysis, the model with ANS had higher clinical value.

Conclusions

The ANS is a useful predictor and an independent risk factor for postoperative complications after PD. The nomogram with ANS was constructed with better performance and more clinical benefit for predicting postoperative complications.

Postoperative serum procalcitonin versus C-reactive protein as a marker of postoperative infectious complications in pancreatic surgery: a meta-analysis

BACKGROUND

Aim of this meta-analysis was to compare diagnostic accuracy C-reactive protein and procalcitonin between postoperative days 3 and 5 to predict infectious complications post pancreatic surgery.

METHODS

A systemic literature search was performed using MEDLINE, EMBASE and SCOPUS to identify studies evaluating the diagnostic accuracy of procalcitonin and C-reactive protein to predict infectious complications between postoperative days 3 and 5 following pancreatic surgery. A meta-analysis was performed using random-effect model and pooled predictive parameters.

RESULTS

Fifteen studies consisting of 2212 patients were included in the final meta-analysis. Pooled sensitivity, specificity, area under curve and diagnostic odds ratio (DOR) for day 3 C-reactive protein were 62%, 67%, 0.772 and 6.54, respectively. Pooled sensitivity, specificity, area under curve and DOR for day 3 procalcitonin were 74%, 79%, 0.8453 and 11.03, respectively. Sensitivity, specificity, area under the curve and DOR for day 4 C-reactive protein were 60%, 68%, 0.8022 and 11.90, respectively. Sensitivity, specificity and DOR of postoperative day 5 procalcitonin level for predicting infectious complications were 83%, 70% and 12.9, respectively. Pooled sensitivity, specificity, Area Under Receiver Operating Curve and DOR were 50%, 70%, 0.777 and 10.19, respectively.

CONCLUSION

Postoperative procalcitonin is a better marker to predict postoperative infectious complications after pancreatic surgeries.

Postoperative hyperamylasemia (POH) and acute pancreatitis after pancreatoduodenectomy (POAP): State of the art and systematic review

BACKGROUND

Postoperative hyperamylasemia is a frequent finding after pancreatoduodenectomy, but its incidence and clinical implications have not yet been analyzed systematically. The aim of this review is to reappraise the concept of postoperative hyperamylasemia with postoperative acute pancreatitis, including its definition, interpretation, and correlation.

METHODS

Online databases were used to search all available relevant literature published through June 2019. The following search terms were used: "pancreaticoduodenectomy," "amylase," and "pancreatitis." Surgical series reporting data on postoperative hyperamylasemia or postoperative acute pancreatitis were selected and screened.

RESULTS

Among 379 screened studies, 39 papers were included and comprised data from a total of 9,220 patients. Postoperative hyperamylasemia was rarely defined in most of these series, and serum amylase values were measured at different cutoff levels and reported on different postoperative days. The actual levels of serum amylase activity and the representative cutoff levels required to reach a diagnosis of postoperative acute pancreatitis were markedly greater on the first postoperative days and tended to decrease over time. Most studies analyzing postoperative hyperamylasemia focused on its correlation with postoperative pancreatic fistula and other postoperative morbidities. The incidence of postoperative acute pancreatitis varied markedly between studies, with its definition completely lacking in 40% of the analyzed papers. A soft pancreatic parenchyma, a small pancreatic duct, and pathology differing from cancer or chronic pancreatitis were all predisposing factors to the development of postoperative hyperamylasemia.

CONCLUSION

Postoperative hyperamylasemia has been proposed as the biochemical expression of pancreatic parenchymal injury related to localized ischemia and inflammation of the pancreatic stump. Such phenomena, analogous to those associated with acute pancreatitis, could perhaps be renamed as postoperative acute pancreatitis from a clinical standpoint. Patients with postoperative acute pancreatitis experienced an increased rate of all postoperative complications, particularly postoperative pancreatic fistula. Taken together, the discrepancies among previous studies of postoperative hyperamylasemia and postoperative acute pancreatitis outlined in the present review may provide a basis for stronger evidence necessary for the development of universally accepted definitions for postoperative hyperamylasemia and postoperative acute pancreatitis.

Intraoperative bile culture helps choosing antibiotics in pancreaticoduodenectomy: Mechanistic profiling study of complex rink between bacterobilia and postoperative complications

BACKGROUND

Postoperative complications after pancreaticoduodenectomy (PD) is still a major concern. The aim of this study was to propose how to choose antibiotics, based on bacterial sensitivity profiling involved in postoperative complications after PD.

METHODS

Two hundred and thirty patients underwent PD between 2008 and 2018 at Kumamoto University Hospital. We enrolled 121 patients who had both intraoperative bile culture and drain culture on postoperative day (POD) 3. The clinical impact of the bacterial profile on postoperative outcome was retrospectively analyzed.

RESULTS

Multivariate regression analysis revealed that intraperitoneal contamination on POD3 was independently associated with postoperative complications (odds ratio 2.62, P = .02). The bacteria in intraperitoneal drain on POD3 showed 94.9% similarity with those in bile collected during surgery. The major species were Enterococcus (44.6%) and Enterobacter (38.5%). Enterobacter species caused a higher rate of postoperative complications than others (83% vs 54%, P = .04). Three out of five Enterococcus faecium were resistant to carbapenems that were active against all Gram-negative rods.

CONCLUSIONS

Intraperitoneal contamination on POD3, which had similar bacterial species as bile collected during surgery, was correlated with postoperative complications. The bacterial antibiotic sensitivity profile may help selecting optimal antibiotics against infectious postoperative complications in PD.

Evidence-based evaluation of abdominal drainage in pancreatic surgery

Pancreatic fistula is the most common and dreaded complication after pancreatic resection, responsible for high morbidity and mortality (2 to 30%). Prophylactic drainage of the operative site is usually put in place to decrease and/or detect postoperative pancreatic fistula (POPF) early. However, this policy is currently debated and the data from the literature are unclear. The goal of this update is to analyze the most recent evidence-based data with regard to prophylactic abdominal drainage after pancreatic resection (pancreatoduodenectomy [PD] or distal pancreatectomy [PD]). This systematic review of the literature between 1990 and 2020 sought to answer the following questions: should drainage of the operative site after pancreatectomy be routine or adapted to the risk of POPF? If a drainage is used, how long should it remain in the abdomen, what criteria should be used to decide to remove it, and what type of drainage should be preferred? Has the introduction of laparoscopy changed our practice? The literature seems to indicate that it is not possible to recommend the omission of routine drainage after pancreatic resection. By contrast, an approach based on the risk of POPF using the fistula risk score seems beneficial. When a drain is placed, early removal (within 5 days) seems feasible based on clinical, laboratory (C-reactive protein, leukocyte count, neutrophile/lymphocyte ratio, dosage and dynamic of amylase in the drains on D1, D3±D5) and radiological findings. This is in line with the development of enhanced recovery programs after pancreatic surgery. Finally, this literature review did not find any specific data relative to mini-invasive pancreatic surgery.

Systematic review and meta-analysis of factors associated with post-operative pancreatic fistula following pancreatoduodenectomy

BACKGROUND

Many studies have explored factors relating to post-operative pancreatic fistula (POPF); however, the original definition (All-POPF) was revised to include only 'clinically relevant' (CR) POPF. This study identified variables associated with the two International Study Group on Pancreatic Surgery definitions to identify which variables are more strongly associated with CR-POPF.

METHODS

A systematic review identified all studies reporting risk factors for POPF (using both International Study Group on Pancreatic Fistula definitions) following pancreatoduodenectomy. The primary outcome was factors associated with CR-POPF. Meta-analyses (random effects models) of pre-, intra- and post-operative factors associated with POPF in more than two studies were included.

RESULTS

Among 52 774 patients All-POPF (n = 69 studies) and CR-POPF (n = 53 studies) affected 27% (95% confidence interval (CI_95% ) 23-30) and 19% (CI_95% 17-22), respectively. Of the 176 factors, 24 and 17 were associated with All- and CR-POPF, respectively. Absence of pre-operative pancreatitis, presence of renal disease, no pre-operative neoadjuvant therapy, use of post-operative somatostatin analogues, absence of associated venous or arterial resection were associated with CR-POPF but not All-POPF.

CONCLUSION

In conclusion this study demonstrates wide variation in reported rates of POPF and that several risk factors associated with CR-POPF are not used within risk prediction models. Data from this study can be used to shape future studies, research and audit across ethnic and geographic boundaries in POPF following pancreatoduodenectomy.

Preoperative anthropomorphic radiographic measurements can predict postoperative pancreatic fistula formation following pancreatoduodenectomy

BACKGROUND

Postoperative pancreatic fistulae (POPF) are a major contributing factor to pancreatoduodenectomy-associated morbidity. Established risk calculators mostly rely on subjective or intraoperative assessments. We hypothesized that various objective preoperatively determined computed tomography (CT) measurements could predict POPF as well as validated models and allow for more informed operative consent in high-risk patients.

METHODS

Patients undergoing elective pancreatoduodenectomies between January 2013 and April 2018 were identified in a prospective database. Comparative statistical analyses and multivariable logistic regression models were generated to predict POPF development. Model performance was tested with receiver operating characteristics (ROC) curves. Pancreatic neck attenuation (Hounsfield units) was measured in triplicate by pancreatic protocol CT (venous phase, coronal plane) anterior to the portal vein. A pancreatic density index (PDI) was created to adjust for differences in contrast timing by dividing the mean of these measurements by the portal vein attenuation. Total areas of subcutaneous fat and skeletal muscle were calculated at the L3 vertebral level on axial CT. Pancreatic duct (PD) diameter was determined by CT.

RESULTS

In the study period 220 patients had elective pancreatoduodenectomies with 35 (16%) developing a POPF of any grade. Multivariable regression analysis revealed that demographics (age, sex, and race) were not associated with POPF, yet patients resected for pancreatic adenocarcinoma or chronic pancreatitis were less likely to develop a POPF (10 vs. 24%; p = 0.004). ROC curves were created using various combinations of gland texture, body mass index, skeletal muscle index, sarcopenia, PDI, PD diameter, and subcutaneous fat area indexed for height (SFI). A model replacing gland texture with SFI and PDI (AUC 0.844) had similar predictive performance as the established model (p = 0.169).

CONCLUSION

A combination of preoperative objective CT measurements can adequately predict POPF and is comparable to established models relying on subjective intraoperative variables. Validation in a larger dataset would allow for better preoperative stratification of high-risk patients and improve informed consent among this patient population.

C-reactive protein is superior to white blood cell count for early detection of complications after pancreatoduodenectomy: a retrospective multicenter cohort study

BACKGROUND

Early detection of major complications after pancreatoduodenectomy could improve patient management and decrease the "failure-to-rescue" rate. In this retrospective cohort study, we aimed to compare the value of C-reactive protein (CRP) and white blood cell count (WBC) in the early detection of complications after pancreatoduodenectomy.

METHODS

We assessed pancreatoduodenectomies between January 2012 and December 2017. Major complications were defined as grade III or higher according to the Clavien-Dindo classification. Postoperative pancreatic fistula (POPF) was a secondary endpoint. ROC-curve and logistic regression analysis were performed for CRP and WBC. Results were validated in an external cohort.

RESULTS

In the development cohort (n = 285), 103 (36.1%) patients experienced a major complication. CRP was superior to WBC in detecting major complications on postoperative day (POD) 3 (AUC:0.74 vs. 0.54, P < 0.001) and POD 5 (AUC:0.77 vs. 0.68, P = 0.031), however not on POD 7 (AUC:0.77 vs. 0.76, P = 0.773). These results were confirmed in multivariable analysis and in the validation cohort (n = 202). CRP was also superior to WBC in detecting POPF on POD 3 (AUC: 0.78 vs. 0.54, P < 0.001) and POD 5 (AUC: 0.83 vs. 0.71, P < 0.001).

CONCLUSION

CRP appears to be superior to WBC in the early detection of major complications and POPF after pancreatoduodenectomy.

Prospective study on predictability of complications by pancreatic surgeons

PURPOSE

We evaluated the intuition of expert pancreatic surgeons, in predicting the associated risk of pancreatic resection and compared this "intuition" to actual operative follow-up. The objective was to avoid major complications following pancreatic resection, which remains a challenge.

METHODS

From January 2015 to February 2018, all patients who were 18 years old or more undergoing a pancreatic resection (pancreaticoduodenectomy [PD], distal pancreatectomy [DP], or central pancreatectomy [CP]) for pancreatic lesions were included. Preoperatively and postoperatively, all surgeons completed a form assessing the expected potential occurrence of clinically relevant postoperative pancreatic fistula (CR-POPF: grade B or C), postoperative hemorrhage, and length of stay.

RESULTS

Preoperative intuition was assessed for 101 patients for 52 PD, 44 DP, and 5 CP cases. Overall mortality and morbidity rates were 6.9% (n = 7) and 67.3% (n = 68), respectively, and 38 patients (37.6%) developed a POPF, including 27 (26.7%) CR-POPF. Concordance between preoperative intuition of CR-POPF occurrence and reality was minimal, with a Cohen's kappa coefficient (κ) of 0.175 (P value = 0.009), and the same result was obtained between postoperative intuition and reality (κ = 0.351; P < 0.001). When the pancreatic parenchyma was hard, surgeons predicted the absence of CR-POPF with a negative predictive value of 91.3%. However, they were not able to predict the occurrence of CR-POPF when the pancreas was soft (positive predictive value 48%).

CONCLUSIONS

This study assessed for the first time the surgeon's intuition in pancreatic surgery, and demonstrated that pancreatic surgeons cannot accurately assess outcomes except when the pancreatic parenchyma is hard.

HYAL-1-induced autophagy facilitates pancreatic fistula for patients who underwent pancreaticoduodenectomy

The main mechanism of hyaluronidase 1(HYAL-1) in the development of postoperative pancreatic fistula (POPF) after pancreatoduodenectomy (PD) was unknown. In this study, a comprehensive inventory of pre-, intra-, and postoperative clinical and biological data of two cohorts (62 pancreatic cancer [PCa] and 111 pancreatic ductal adenocarcinoma [PDAC]) which could induce POPF were retrospectively analyzed. Then, a total of 7644 genes correlated with HYAL-1 was predicted in PDAC tissues and the enriched pathway, kinase targets and biological process of those correlated genes were evaluated. Finally, a mouse pancreatic fistula (PF) model was first built and in vitro studies were performed to investigate the effects of HYAL-1 on PF progression. Our data indicated that preoperative serum HYAL-1 level, pancreatic fibrosis score, and pancreatic duct size were valuable factors for detecting POPF of Grade B and C. The serum HYAL-1 level of 2.07 mg/ml and pancreatic fibrosis score of 2.5 were proposed as the cutoff values for indicating POPF. The bioinformatic analysis and in vitro and in vivo studies demonstrated that HYAL-1 facilitates pancreatic acinar cell autophagy via the dephosphorylation of adenosine 5'-monophosphate-activated protein kinase (AMPK) and signal transducers and activators of transcription 3 (STAT3) signaling pathways, which exacerbate pancreatic secretion and inflammation. In summary, the preoperative serum HYAL-1 was a significant predictor for POPF in patients who underwent PD. Tumor-induced HYAL-1 is one of core risk in accelerating PF and then promoting pancreatic secretion and acute inflammation response through the AMPK and STAT3-induced autophagy.

Early recognition of clinically relevant postoperative pancreatic fistula: a systematic review

BACKGROUND

Early recognition of postoperative pancreatic fistula might decrease the risk of subsequent life threatening complications. The aim of this review was to systematically evaluate the accuracy of postoperative clinical, biochemical and radiologic variables for early recognition of clinically relevant postoperative pancreatic fistula.

METHODS

A systematic literature search was performed up to August 2018. Clinical studies reporting on the association between postoperative variables and clinically relevant postoperative pancreatic fistula were included. Variables were stratified: early prediction (postoperative day 1-2) versus early diagnosis (day 3) and had to be reported in 2 cohorts.

RESULTS

Overall, 37 included studies reported on 17 different diagnostic variables after 8701 pancreatic resections. Clinically relevant postoperative pancreatic fistula occurred in 1532/8701 patients (18%). Early prediction variables included elevated serum and drain amylase (day 1). Identified variables for early diagnosis were: non-serous drain efflux (day 3); positive drain culture (day 3); elevated temperature (any day); elevated C-Reactive Protein (CRP; day 4); elevated white blood cell count (day 4) and peripancreatic collections on computed tomography (CT; day 5-10).

CONCLUSION

This review provides a comprehensive overview of postoperative variables associated with clinically relevant pancreatic fistula. Incorporation of variables in future algorithms could potentially mitigate the clinical impact of postoperative pancreatic fistula.

A score model based on pancreatic steatosis and fibrosis and pancreatic duct diameter to predict postoperative pancreatic fistula after Pancreatoduodenectomy

PURPOSES

To establish a scoring model for the risk of postoperative pancreatic fistula (POPF) following pancreatoduodenectomy (PD).

METHODS

PD Patients from 7 institutions in 2 independent sets: developmental (n = 457) and validation cohort (n = 152) were retrospectively enrolled and analyzed. Pancreatic Fibrosis (PF) and Pancreatic Steatosis (PS) were assessed by pathological examination of the pancreatic stump.

RESULTS

Stepwise univariate and multivariate analysis indicated that pancreatic duct diameter ≤ 3 mm, increased PS and decreased PF were independent risk factors for POPF and Clinically Relevant Postoperative Pancreatic Fistula (CR-POPF). Based on the relative weight and odds ratio of each factor in the POPF, a simplified scoring model was developed. And patients were stratified into high-risk group (22~28 points), medium-risk group (15~21 points) and low-risk group (8~14 points). The receiver operating characteristic curve demonstrated that the Area under the curve for the predictive model was 0.868 and 0.887 in the model design group and the external validation group.

CONCLUSIONS

This study establishes a simplified scoring model based on accurately and quantitatively measuring the PS, PF and pancreatic duct diameter. The scoring model accurately predicted the risk of POPF.

Novel risk scoring system for prediction of pancreatic fistula after pancreaticoduodenectomy

BACKGROUND

The available prediction models for clinically relevant postoperative pancreatic fistula (CR-POPF) do not incorporate both preoperative and intraoperative variables.

AIM

To construct a new risk scoring system for CR-POPF that includes both preoperative and intraoperative factors.

METHODS

This was a retrospective study of patients who underwent pancreaticoduodenectomy (PD) or pylorus-preserving PD (PPPD) between January 2011 and December 2016 at the First Affiliated Hospital of Soochow University. Patients were divided into a study (01/2011 to 12/2014) or validation (01/2015 to 12/2016) group according to the time of admission. POPF severity was classified into three grades: Biochemical leak (grade A) and CR-POPF (grades B and C). Logistic regression was used to create a predictive scoring system.

RESULTS

Preoperative serum albumin ≥ 35 g/L [P = 0.032, odds ratio (OR) = 0.92, 95% confidence interval (CI): 0.85-0.99], hard pancreatic texture (P = 0.004, OR = 0.25, 95%CI: 0.10-0.64), pancreatic duct diameter ≥ 3 mm (P = 0.029, OR = 0.50, 95%CI: 0.27-0.93), and intraoperative blood loss ≥ 500 mL (P = 0.006, OR = 1.002, 95%CI: 1.001-1.003) were independently associated with CR-POPF. We established a 10-point risk scoring system to predict CR-POPF. The area under the curve was 0.821 (95%CI: 0.736-0.905) and the cut-off value was 3.5. Including drain amylase levels improved the predictive power of the model.

CONCLUSION

This study established a 10-point scoring system to predict CR-POPF after PD/PPPD using preoperative and intraoperative parameters. Ultimately, this system could be used to distinguish between high- and low-risk populations in order to facilitate timely interventions after PD.

Alternative Fistula Risk Score for Pancreatoduodenectomy (a-FRS): Design and International External Validation

OBJECTIVE

The aim of this study was to develop an alternative fistula risk score (a-FRS) for postoperative pancreatic fistula (POPF) after pancreatoduodenectomy, without blood loss as a predictor.

BACKGROUND

Blood loss, one of the predictors of the original-FRS, was not a significant factor during 2 recent external validations.

METHODS

The a-FRS was developed in 2 databases: the Dutch Pancreatic Cancer Audit (18 centers) and the University Hospital Southampton NHS. Primary outcome was grade B/C POPF according to the 2005 International Study Group on Pancreatic Surgery (ISGPS) definition. The score was externally validated in 2 independent databases (University Hospital of Verona and University Hospital of Pennsylvania), using both 2005 and 2016 ISGPS definitions. The a-FRS was also compared with the original-FRS.

RESULTS

For model design, 1924 patients were included of whom 12% developed POPF. Three predictors were strongly associated with POPF: soft pancreatic texture [odds ratio (OR) 2.58, 95% confidence interval (95% CI) 1.80-3.69], small pancreatic duct diameter (per mm increase, OR: 0.68, 95% CI: 0.61-0.76), and high body mass index (BMI) (per kg/m increase, OR: 1.07, 95% CI: 1.04-1.11). Discrimination was adequate with an area under curve (AUC) of 0.75 (95% CI: 0.71-0.78) after internal validation, and 0.78 (0.74-0.82) after external validation. The predictive capacity of a-FRS was comparable with the original-FRS, both for the 2005 definition (AUC 0.78 vs 0.75, P = 0.03), and 2016 definition (AUC 0.72 vs 0.70, P = 0.05).

CONCLUSION

The a-FRS predicts POPF after pancreatoduodenectomy based on 3 easily available variables (pancreatic texture, duct diameter, BMI) without blood loss and pathology, and was successfully validated for both the 2005 and 2016 POPF definition. The online calculator is available at www.pancreascalculator.com.

Developing and validating a center-specific preoperative prediction calculator for risk of pancreaticoduodenectomy

BACKGROUND

The American College of Surgeons (ACS) Surgical Risk Calculator predicts postoperative risk based on preoperative variables. The ACS model was compared to an institution-specific risk calculator for pancreaticoduodenectomy (PD).

METHODS

Observed outcomes were compared with those predicted by the ACS and institutional models. Receiver operating characteristic (ROC) analysis evaluated the models' predictive ability. Institutional models were evaluated with retrospective and prospective internal validation.

RESULTS

Brier scores indicate equivalent aggregate predictive ability. ROC values for the institutional model (ROC: 0.675-0.881, P < 0.01) indicate superior individual event occurrence prediction (ACS ROC: 0.404-0.749, P < 0.01-0.860). Institutional models' accuracy was upheld in retrospective (ROC: 0.765-0.912) and prospective (ROC: 0.882-0.974) internal validation.

CONCLUSIONS

Identifying higher-risk patients allows for individualized care. While ACS and institutional models accurately predict average complication occurrence, the institutional models are superior at predicting individualized outcomes. Predictive metrics specific to PD center volume may more accurately predict outcomes.

Validation of Fistula Risk Score calculator in diverse North American HPB practices

BACKGROUND

Fistula Risk Score (FRS) is a previously developed tool to assess the risk of clinically relevant postoperative pancreatic fistula (CR-POPF) following pancreatoduodenectomy (PD).

METHODS

Prospectively collected databases from 4 university affiliated and non-affiliated HPB centers in United States and Canada were used. The influence of individual baseline characteristics, FRS and FRS group on CR-POPF was assessed in univariate and multivariate analyses. FRS calculator performance was assessed using a C-statistic.

RESULTS

444 patients were identified. Pathology, soft pancreas texture and pancreatic duct size were associated with CR-POPF rates (p < 0.001 for each); EBL was not (p = 0.067). The negligible risk group consisted of 50 (11.3%) patients, low risk of 118 (26.6%), moderate 234 (52.7%) and high risk group of 42 (9.5%) patients. The overall rate of CR-POPF was 20%. Of the patients in the negligible risk group, 2% developed CR-POPF, 13.6% of the low risk, 23.1% moderate and 42.9% in the high risk group (p < 0.001). Overall C-statistic was 0.719.

CONCLUSION

FRS is robust and able to stratify the risk of developing CR-POPF following PD in diverse North American academic and non-academic institutions. The FRS should be used in research and to guide clinical management of patients post PD in these institutions.

Impact of obesity on short and long term results following a pancreatico-duodenectomy

BACKGROUND

The impact of obesity on short and long term outcomes following a pancreatico-duodenectomy (PD) is still unclear and needs further clarification.

METHODS

Demographic, operative and outcomes data in 524 patients undergoing PD were analysed.

RESULTS

Ninety-seven patients (18.5%) had BMI greater than or equal to 30 kg/m2 (group A) and 427 patients (81.5%) had BMI less than 30 kg/m2 (group B). Group A had a significantly greater operative duration, (375 vs 360 min, p = 0.024) and a higher intra-operative blood loss, (660 vs 500 ml, p = 0.005). Post-operative pancreatic fistula (POPF) were more common in Group A (28.9% vs 16.2%, p = 0.006), this difference was also observed when considering only major POPF (Grade B and C) (16.5% vs 8.0%, p = 0.020). Intra-abdominal collections were higher in Group A, 28.9% compared to 19.0% in Group B (p = 0.037). On multivariate analysis BMI (OR 2.006; 95% CI 1.147-4.985, p = 0.040), small pancreatic duct (OR 2.755; 95% CI 1.589-2.968, p = 0.026) and soft pancreas (OR 2.289; 95% CI 1.126-3.665, p = 0.040) were found to be independent factors for POPF. The median survival for adenocarcinomas was 20 months in Group A and 22 months in Group B, (p = 0.109).

CONCLUSION

Patients with BMI ≥ 30 are at an increased risk of developing pancreatic fistula following PD. Obesity does not appear to have an impact on long term outcomes in patients undergoing a PD for adenocarcinomas.

C-Reactive Protein Was an Early Predictor of Postoperative Infectious Complications After Pancreaticoduodenectomy for Pancreatic Cancer

Objective

The study objective was to assess the predictive value of C-reactive protein (CRP) for the early detection of postoperative infectious complications (PICs) after pancreaticoduodenectomy.

Summary of Background Data

The incidence of PICs after pancreaticoduodenectomy still remains high and a clinically relevant problem, despite improvements in the surgical procedure.

Methods

We examined 110 consecutive patients who underwent pancreaticoduodenectomy for primary pancreatic cancer between 2006 and 2014. The predictive value was assessed by estimating the area under the receiver operating characteristic curve (AUC). Clinical and laboratory data, including CRP, were analyzed with univariate and multivariate logistic regression analyses to identify predictors of PICs of grade III or higher according to the Clavien-Dindo classification.

Results

PICs of grade III or higher occurred in 13 patients [11.8%; 95% confidence interval (CI), 6.45%–19.36%]. CRP level on postoperative day 3 (POD 3) was a good predictor of PICs (AUC, 0.815; 95% CI, 0.651–0.980), showing the highest accuracy among clinical and laboratory data. A cutoff value of 13.2 mg/dL yielded a sensitivity of 0.846 and a specificity of 0.794. On multivariate analysis, a POD 3 CRP level of 13.2 mg/dL or higher (odds ratio, 20.0; 95% CI, 4.07–97.9; P = 0.002) was a significant predictor of PICs after pancreaticoduodenectomy.

Conclusions

CRP elevation above 13.2 mg/dL on POD 3 is a significant predictive factor for PICs and should prompt an intense clinical search and therapeutic approach for PICs.

Amylase in drain fluid for the diagnosis of pancreatic leak in post-pancreatic resection

BACKGROUND

The treatment of people with clinically significant postoperative pancreatic leaks is different from those without clinically significant pancreatic leaks. It is important to know the diagnostic accuracy of drain fluid amylase as a triage test for the detection of clinically significant pancreatic leaks, so that an informed decision can be made as to whether the patient with a suspected pancreatic leak needs further investigations and treatment. There is currently no systematic review of the diagnostic test accuracy of drain fluid amylase for the diagnosis of clinically relevant pancreatic leak.

OBJECTIVES

To determine the diagnostic accuracy of amylase in drain fluid at 48 hours or more for the diagnosis of pancreatic leak in people who had undergone pancreatic resection.

SEARCH METHODS

We searched MEDLINE, Embase, the Science Citation Index Expanded, and the National Institute for Health Research Health Technology Assessment (NIHR HTA) websites up to 20 February 2017. We searched the references of the included studies to identify additional studies. We did not restrict studies based on language or publication status, or whether data were collected prospectively or retrospectively. We also performed a 'related search' and 'citing reference' search in MEDLINE and Embase.

SELECTION CRITERIA

We included all studies that evaluated the diagnostic test accuracy of amylase in the drain fluid at 48 hours or more for the diagnosis of pancreatic leak in people who had undergone pancreatic resection excluding total pancreatectomy. We planned to exclude case-control studies because these studies are prone to bias, but did not find any. At least two authors independently searched and screened the references produced by the search to identify relevant studies.

DATA COLLECTION AND ANALYSIS

Two review authors independently extracted data from the included studies. The included studies reported drain fluid amylase on different postoperative days and measured at different cut-off levels, so it was not possible to perform a meta-analysis using the bivariate model as planned. We have reported the sensitivity, specificity, post-test probability of a positive and negative drain fluid amylase along with 95% confidence interval (CI) on each of the different postoperative days and measured at different cut-off levels.

MAIN RESULTS

A total of five studies including 868 participants met the inclusion criteria for this review. The five studies included in this review reported the value of drain fluid amylase at different thresholds and different postoperative days. The sensitivities and specificities were variable; the sensitivities ranged between 0.72 and 1.00 while the specificities ranged between 0.73 and 0.99 for different thresholds on different postoperative days. At the median prevalence (pre-test probability) of 15.9%, the post-test probabilities for pancreatic leak ranged between 35.9% and 95.4% for a positive drain fluid amylase test and ranged between 0% and 5.5% for a negative drain fluid amylase test.None of the studies used the reference standard of confirmation by surgery or by a combination of surgery and clinical follow-up, but used the International Study Group on Pancreatic Fistula (ISGPF) grade B and C as the reference standard. The overall methodological quality was unclear or high in all the studies.

AUTHORS' CONCLUSIONS

Because of the paucity of data and methodological deficiencies in the studies, we are uncertain whether drain fluid amylase should be used as a method for testing for pancreatic leak in an unselected population after pancreatic resection; and we judge that the optimal cut-off of drain fluid amylase for making the diagnosis of pancreatic leak is also not clear. Further well-designed diagnostic test accuracy studies with pre-specified index test threshold of drain fluid amylase (at three times more on postoperative day 5 or another suitable pre-specified threshold), appropriate follow-up (for at least six to eight weeks to ensure that there are no pancreatic leaks), and clearly defined reference standards (of surgical, clinical, and radiological confirmation of pancreatic leak) are important to reliably determine the diagnostic accuracy of drain fluid amylase in the diagnosis of pancreatic leak.

Role of C-Reactive Protein Assessment as Early Predictor of Surgical Site Infections Development after Pancreaticoduodenectomy

BACKGROUND

Surgical site infections (SSIs) are extremely common in pancreatic surgery and explain its considerable morbidity and mortality, even in tertiary centers. Early detection of these complications, with the help of laboratory assays, improve clinical outcome. The aim of the present study is to evaluate C-reactive protein (CRP) diagnostic accuracy as early predictor of SSIs after pancreaticoduodenectomy (PD).

METHODOLOGY

We considered 251 consecutive PD. We prospectively recorded preoperative clinical and anthropometric data, intraoperative details and the postoperative outcome. In the first pool of consecutive patients (n = 150), we analyzed CRP levels from postoperative day 1 to 7 and investigated the prediction of SSIs. We then validated the diagnostic accuracy on the following 101 consecutive cases.

RESULTS

At multivariate analysis, high BMI and preoperative biliary stenting appeared to be independently associated with SSIs and organ-space SSI development. The CRP cutoff of 17.27 mg/dl on postoperative day 3 (78% sensitivity, 79% specificity) and of 14.72 mg/dl on postoperative day 4 (87% sensitivity, 82% specificity) was in a position to predict the course of 78.2 and 80.2% of patients, respectively.

CONCLUSIONS

CRP on postoperative days 3 and 4 seems able to predict postoperative course, selecting patients deserving intensification of diagnostic assessment; patients not satisfying these conditions could be reasonably directed toward early discharge.

Systematic Review and Meta-Analysis of Pancreatic Amylase Value on Postoperative Day 1 After Pancreatic Resection to Predict Postoperative Pancreatic Fistula

Early detection of postoperative pancreatic fistula (POPF) may help to improve the outcome following pancreatic surgery, and exclusion of POPF may allow early drain removal which can accelerate recovery. The aim of this study was to evaluate the diagnostic accuracy of drain/plasma pancreatic amylase values on postoperative day 1 (DPA1/PPA1) in POPF by means of a systemic review and meta-analysis.Online journal databases and a manual search up to March 2015 were used. Studies clearly documenting DPA1 or PPA1 in predicting overall POPF (Grade 0 vs A+B+C) or clinically relevant POPF (Grade 0+A vs B+C) following pancreatic surgery were selected. Pooled predictive parameters were performed using STATA 12.0.Fifteen studies were finally identified with a total of 4331 patients. The pooled sensitivity and specificity of DPA1 were 0.92 (95% confidence interval (CI) 0.81-0.96) and 0.77 (95% CI 0.64-0.86) for predicting overall POPF and 0.79 (95% CI 0.61-0.90) and 0.83 (95% CI 0.74-0.89) for predicting clinically relevant POPF. The pooled sensitivity and specificity of PPA1 were 0.74 (95% CI 0.63-0.82) and 0.62 (95% CI 0.55-0.70) for overall POPF. After the DPA1 at/over cutoff values for overall POPF or clinically relevant POPF, corresponding post-test probability (Post-test (+)) (if pretest probability was 50%) was 80% and 82% respectively, while, if values were below the cutoff values, the post-test probability (Post-test (-)) was 10% and 20% respectively. Post-test (+) and Post-test (-) of PPA1 for overall POPF were 66% and 30% respectively. In subgroup analysis, the summary sensitivities of cutoff <1000 group and cutoff >1000 group were 0.96 (0.92-0.98) and 0.85 (0.64-0.95), respectively; the summary specificities were 0.59 (0.44-0.72) and 0.86 (0.80-0.91) respectively. Positive LR were 2.3 (1.7-3.3) and 6.2 (3.7-10.2) respectively. Negative LR were 0.06 (0.03-0.14) and 0.18 (0.07-0.47) respectively.DPA1 is a useful predictive test for overall POPF and clinically relevant POPF which has good sensitivity and specificity based on the current studies. Meanwhile, it should be cautiously applied to clinical practice because cutoffs had a wide range between studies.

Limited utility of inflammatory markers in the early detection of postoperative inflammatory complications after pancreatic resection: Cohort study and meta-analyses

PURPOSE

To examine the diagnostic accuracy of systemic inflammatory markers in early prediction of inflammatory postoperative complications (IPC) and clinically-relevant pancreatic fistula (PF).

METHODS

Preoperative and postoperative [until postoperative day (POD) 4)] measurements of hemoglobin, white blood cell counts (WBC), neutrophil/lymphocyte ratio (NLR) and C-reactive protein (CRP) were correlated with IPC and PF. Meta-analyses of biochemical predictors were performed.

RESULTS

Ninety-two out of 378 patients developed IPC, PF occurred in 31. Preoperative WBC (OR 1.0001, 95% CI: 1.0001-1.0002, p = 0.02), NLR on POD2 (OR 1.05, 95% CI: 1.006-1.1, p = 0.02) and CRP on POD4 (OR 1.006, 95% CI: 1.002-1.01, p = 0.02) predicted IPC at multivariate analysis. The model including these three variables showed a diagnostic accuracy of 76.8% (sensitivity 20, specificity 97%.14; PPV 71.43, PPN 77.27) and, at logistic regression analysis an OR of 8.5 (95% CI: 2.5-28.6, p < 0.001). Only CRP >272 on POD3 (OR 3.32, 95% CI: 1.46-7.52, p = 0.003) was associated with PF with a diagnostic accuracy of 74% (sensitivity 54.5, specificity 78.5; PPV 16.88, NPV 94.25). Meta-analyses of available data suggested sensitivity of 75.3% (95% CI 66.7-82.6) and specificity of 75.5% (95% CI 61.3-85.7). However, these studies were significantly heterogeneous.

CONCLUSIONS

Readily available, routine tests have limited utility in predicting IPC. Further research is required to develop novel biomarkers to aid management of these patients.

Drain amylase value as an early predictor of pancreatic fistula after cephalic duodenopancreatectomy

AIM: To determine predictors of clinically relevant pancreatic fistulas (CRPF) by measuring drain fluid amylase (DFA) in the early postoperative period.

METHODS: This prospective clinical study included 382 patients with periampullary tumors that were surgically resected at our department between March 2005 and October 2012. A cephalic duodenopancreatectomy (DP) was performed on all patients. Two closed suction drains were placed at the end of the surgery. The highest postoperative DFA value was recorded and analyzed during the first three postoperative days and on subsequent days if the drains were kept longer. Pancreatic fistula (PF) was classified according to the International Study Group of Pancreatic Fistula (ISGPF) criteria. Postoperative complications were defined according to the Dindo-Clavien classification. All data were statistically analyzed. The optimal thresholds of DFA levels on the first, second and third postoperative days were estimated by constructing receiver operating curves, generated by calculating the sensitivities and specificities of the DFA levels. The DFA level limits were used to differentiate between the group without PF and the groups with biochemical pancreatic fistula (BPF) and CRPF.

RESULTS: Pylorus-preserving duodenopancreatectomy was performed on 289 (75.6%) patients, while the remaining patients underwent a classic Whipple procedure (CW). The total incidence of PF was 37.7% (grade A 22.8%, grade B 11.0% and grade C 3.9%). Soft pancreatic texture (SPT) was present in 58.3% of patients who developed PF. Mortality was 4.2%. The median DFA value on the first postoperative day (DFA1) in patients who developed PF was 4520 U/L (range 350-99000 U/L) for grade A fistula (BPF) with a SPT and a diameter of the main pancreatic duct (MPD) of ≤ 3 mm. For grade B/C (CRPF), the median DFA1 value was 8501 U/L (range 377-92060 U/L) with a SPT and MPD of ≤ 3 mm. These values were significantly higher when compared to the patients who did not have PF (122; range 5-37875 U/L). The upper limit of DFA values for the first 3 postoperative days in the examined stages of PF were: DFA1 1200 U/L for the BPF and CRPF; DFA3 350 U/L for BPF and DFA3 800 U/L for CRPF. The determined values were highly significant and demonstrated a reliable diagnostic test for both BPF and CRPF.

CONCLUSION: DFA1 ≥ 1200 U/L is an important predictive factor for PF of any degree. The trend of DFA3 (decrease of < 50%) compared to DFA1 is a significant factor in the differentiation of CRPF from transient BPF.

Is routine drainage necessary after pancreaticoduodenectomy?

With the development of imaging technology and surgical techniques, pancreatic resections to treat pancreatic tumors, ampulla tumors, and other pancreatic diseases have increased. Pancreaticoduodenectomy, one type of pancreatic resection, is a complex surgery with the loss of pancreatic integrity and various anastomoses. Complications after pancreaticoduodenectomy such as pancreatic fistulas and anastomosis leakage are common and significantly associated with patient outcomes. Pancreatic fistula is one of the most important postoperative complications; this condition can cause intraperitoneal hemorrhage, septic shock, or even death. An effective way has not yet been found to avoid the occurrence of pancreatic fistula. In most medical centers, the frequency of pancreatic fistula has remained between 9% and 13%. The early detection and routine drainage of anastomotic fistulas, pancreatic fistulas, bleeding, or other intra-abdominal fluid collections after pancreatic resections are considered as important and effective ways to reduce postoperative complications and the mortality rate. However, many recent studies have argued that routine drainage after abdominal operations, including pancreaticoduodenectomies, does not affect the incidence of postoperative complications. Although inserting drains after pancreatic resections continues to be a routine procedure, its necessity remains controversial. This article reviews studies of the advantages and disadvantages of routine drainage after pancreaticoduodenectomy and discusses the necessity of this procedure.