Prospective validation of a preoperative risk score model based on pancreatic texture to predict postoperative pancreatic fistula 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.

A novel laparoscopic pancreaticoduodenal training model: optimization of the learning curve and simplification of postoperative complications

PURPOSE

Laparoscopic pancreaticoduodenectomy requires a long learning curve. A preoperative training system was established to optimize the surgeons' learning curve and reduce the incidence rate of complications at the beginning of the curve.

METHODS

The laparoscopic pancreaticojejunostomy model, and choledochojejunostomy and gastrojejunostomy training systems were developed, and corresponding evaluation systems were also defined. Surgeons B and C performed laparoscopic pancreaticoduodenectomy after completing training session. Surgical outcomes, postoperative complications and their learning curves were analyzed.

RESULTS

Patients operated by surgeons B and C experienced shorter operative durations following training session than those in nontrained group (called A) ( P <0.001). B and C began entering the inflection point at the 26th and 20th case in learning curve, respectively. The incidence of postoperative pancreatic fistula in group B was 3.3%, significantly lower than 13.1% in group A ( P =0.047). Patients in group B showed significantly lower incidence of biliary-enteric anastomosis leakage (0% vs. 8.2%, P =0.029) and Clavien-Dindo classification greater than or equal to 3 (3.3% vs. 14.8%, P =0.027) compared with those in group A. The incidence of surgical site infection in groups B (3.3%, P =0.004) and C (4.9%, P =0.012) was significantly lower than that in group A (19.7%). Moreover, the length of postoperative hospital stay was significantly shorter in groups B (12.5±5.9 days, P =0.002) and C (13.7±6.5 days, P =0.002) compared with group A (16.7±8.5 days).

CONCLUSIONS

The laparoscopic pancreaticojejunostomy training model and evaluation system can shorten the operative duration, lower the risk of postoperative complications, and shorten the length of hospital stay.

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 Transparent Reporting of a multivariable prediction model for Individual Prognosis Or Diagnosis analysis to evaluate the quality of reporting of postoperative pancreatic fistula prediction models after pancreatoduodenectomy: A systematic review

BACKGROUND

Postoperative pancreatic fistula is a frequent and potentially lethal complication after pancreatoduodenectomy. Several models have been developed to predict postoperative pancreatic fistula risk. This study was performed to evaluate the quality of reporting of postoperative pancreatic fistula prediction models after pancreatoduodenectomy using the Transparent Reporting of a multivariable prediction model for Individual Prognosis Or Diagnosis (TRIPOD) checklist that provides guidelines on reporting prediction models to enhance transparency and to help in the decision-making regarding the implementation of the appropriate risk models into clinical practice.

METHODS

Studies that described prediction models to predict postoperative pancreatic fistula after pancreatoduodenectomy were searched according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. The TRIPOD checklist was used to evaluate the adherence rate. The area under the curve and other performance measures were extracted if reported. A quadrant matrix chart is created to plot the area under the curve against TRIPOD adherence rate to find models with a combination of above-average TRIPOD adherence and area under the curve.

RESULTS

In total, 52 predictive models were included (23 development, 15 external validation, 4 incremental value, and 10 development and external validation). No risk model achieved 100% adherence to the TRIPOD. The mean adherence rate was 65%. Most authors failed to report on missing data and actions to blind assessment of predictors. Thirteen models had an above-average performance for TRIPOD checklist adherence and area under the curve.

CONCLUSION

Although the average TRIPOD adherence rate for postoperative pancreatic fistula models after pancreatoduodenectomy was 65%, higher compared to other published models, it does not meet TRIPOD standards for transparency. This study identified 13 models that performed above average in TRIPOD adherence and area under the curve, which could be the appropriate models to be used in clinical practice.

A Simple Classification of Pancreatic Duct Size and Texture Predicts Postoperative Pancreatic Fistula: A classification of the International Study Group of Pancreatic Surgery

OBJECTIVE

The aim of this study was to develop a classification system for pancreas-associated risk factors in pancreatoduodenectomy (PD).

SUMMARY BACKGROUND DATA

Postoperative pancreatic fistula (POPF) is the most relevant PD-associated complication. A simple standardized surgical reporting system based on pancreas-associated risk factors is lacking.

METHODS

A systematic literature search was conducted to identify studies investigating clinically relevant (CR) POPF (CR-POPF) and pancreas-associated risk factors after PD. A meta-analysis of CR-POPF rate for texture of the pancreas (soft vs not-soft) and main pancreatic duct (MPD) diameter was performed using the Mantel-Haenszel method. Based on the results, the International Study Group of Pancreatic Surgery (ISGPS) proposes the following classification: A, not-soft (hard) texture and MPD >3 mm; B, not-soft (hard) texture and MPD ≤3 mm; C, soft texture and MPD >3 mm; D, soft texture and MPD ≤3 mm. The classification was evaluated in a multi-institutional, international cohort.

RESULTS

Of the 2917 articles identified, 108 studies were included in the analyses. Soft pancreatic texture was significantly associated with the development of CR-POPF [odds ratio (OR) 4.24, 95% confidence interval (CI) 3.67-4.89, P < 0.01) following PD. Similarly, MPD diameter ≤3 mm significantly increased CR-POPF risk compared with >3 mm diameter MPDs (OR 3.66, 95% CI 2.62-5.12, P < 0.01). The proposed 4-stage system was confirmed in an independent cohort of 5533 patients with CR-POPF rates of 3.5%, 6.2%, 16.6%, and 23.2% for type A-D, respectively ( P < 0.001).

CONCLUSION

For future pancreatic surgical outcomes studies, the ISGPS recommends reporting these risk factors according to the proposed classification system for better comparability of results.

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.

Perioperative risk of pancreatic head resection-nomogram-based prediction of severe postoperative complications as a decisional aid for clinical practice

PURPOSE

To develop nomograms for pre- and early-postoperative risk assessment of patients undergoing pancreatic head resection.

METHODS

Clinical data from 956 patients were collected in a prospectively maintained database. A test (n = 772) and a validation cohort (n = 184) were randomly generated. Uni- and multi-variate analysis and nomogram construction were performed to predict severe postoperative complications (Clavien-Dindo Grades III-V) in the test cohort. External validation was performed with the validation cohort.

RESULTS

We identified ASA score, indication for surgery, body mass index (BMI), preoperative white blood cell (WBC) count, and preoperative alkaline phosphatase as preoperative factors associated with an increased perioperative risk for complications. Additionally to ASA score, BMI, indication for surgery, and the preoperative alkaline phosphatase, the following postoperative parameters were identified as risk factors in the early postoperative setting: the need for intraoperative blood transfusion, operation time, maximum WBC on postoperative day (POD) 1-3, and maximum serum amylase on POD 1-3. Two nomograms were developed on the basis of these risk factors and showed accurate risk estimation for severe postoperative complications (ROC-AUC-values for Grades III-V-preoperative nomogram: 0.673 (95%, CI: 0.626-0.721); postoperative nomogram: 0.734 (95%, CI: 0.691-0.778); each p ≤ 0.001). Validation yielded ROC-AUC-values for Grades III-V-preoperative nomogram of 0.676 (95%, CI: 0.586-0.766) and postoperative nomogram of 0.677 (95%, CI: 0.591-0.762); each p = 0.001.

CONCLUSION

Easy-to-use nomograms for risk estimation in the pre- and early-postoperative setting were developed. Accurate risk estimation can support the decisional process, especially for IPMN-patients with an increased perioperative risk.

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.

Prediction of pancreatic fistula after pancreatectomy by virtual touch tissue imaging and quantification (VTIQ) technology

OBJECTIVES

The aim of this study was to quantitatively evaluate the stiffness of pancreatic parenchyma and solid focal pancreatic lesions (FPLs) by virtual touch tissue imaging and quantification (VTIQ) technique and to investigate the potential usefulness of VTIQ method in the prediction of post-operative pancreatic fistula (POPF) after pancreatectomy.

METHODS

In this prospective study, patients who scheduled to undergo pancreatectomy were initially enrolled and received VTIQ assessment within one week before surgery. VTIQ elastography (Siemens ACUSON Sequoia, 5C-1 transducer) was used to measure the shear wave velocity (SWV) value of FPLs and the body part pancreatic parenchyma. The palpation stiffness of pancreas was qualitatively evaluated during operation by surgeons. POPF was finally diagnosed and graded through a three-weeks post-operative follow-up according to international study group of pancreatic fistula (ISGPF). SWV values were compared between POPF positive and negative group. Receiver operating characteristic (ROC) analysis was used to evaluate the diagnostic efficacy of SWV value in predicting POPF.

RESULTS

From December 2020 to June 2021, 44 patients were finally enrolled in this study, among which, 26 patients were identified to develop POPF after pancreatectomy. The SWV value of pancreatic parenchyma in POPF positive group was significantly lower than that in POPF negative group (P = 0.001). However, there was no significant difference in palpation stiffness between the two groups (P = 0.124). Besides, neither the SWV value of FPL nor the SWV ratio between FPL to surrounding pancreatic parenchyma differ significantly between POPF positive and negative group (P > 0.05). Taking SWV value of pancreatic parenchyma >1.10 m/s as a cut-off value for predicting POPF, area under the receiver operating characteristic curve (AUROC) was 0.864 with 72.2% sensitivity, 92.3% specificity, 86.7% positive predictive value (PPV) and 82.8% negative predictive value (NPV), respectively.

CONCLUSIONS

VTIQ technique might be a potential non-invasive imaging method to predict POPF before pancreatectomy in future clinical practice.

A case of intraductal papillary mucinous neoplasm developing in the native pancreas after pancreas transplantation treated by total pancreatectomy

Post-transplant patients reportedly have a higher risk of de novo neoplasms. However, intraductal papillary mucinous neoplasm (IPMN) of the native pancreas after pancreas transplantation (PTx) has not been well investigated. The choice of treatment, especially invasive treatment, for de novo neoplasms in transplant patients should consider their impaired immunity. In this context, we present a case of IPMN developing in the native pancreas of a PTx patient. A 53-year-old man underwent a follow-up abdominal computed tomography scan 6 years after a simultaneous pancreas-kidney transplant for type 1 diabetes mellitus with end-stage diabetic nephropathy requiring hemodialysis. The scan revealed IPMN in the pancreas head; an enhancing internal solid component suggested a high risk of malignancy, indicating surgical resection. Partial pancreatectomy or pancreaticoduodenectomy was anatomically indicated, but considering the insulin-secreting ability of the transplanted pancreas and the potential high risk of postoperative pancreatic fistula due to immune impairment after partial pancreatectomy, total pancreatectomy (TP) was performed. The patient is alive with good pancreas graft function, no signs of indigestion for 18 months after TP, and no evidence of IPMN recurrence. This report should help clinicians characterize de novo IPMN in the native pancreas and determine IPMN therapeutic options for transplant patients.

Adverse Impact of Intraoperative Conversion on the Postoperative Course Following Laparoscopic Pancreaticoduodenectomy

PURPOSE

The aim of the current study was to evaluate the adverse clinical impact of intraoperative conversion during laparoscopic pancreaticoduodenectomy (LPD).

MATERIALS AND METHODS

The medical records of patients who underwent pancreaticoduodenectomy (PD) were retrospectively reviewed. Perioperative clinical variables were compared between patients who underwent converted PD (cPD) and initially planned open PD (OPD) to investigate the clinical impact and predictive factors of intraoperative conversion during LPD.

RESULTS

A total of 171 patients were included. Among them, 31 patients (19.3%) were found to have intraoperative conversion during LPD. Failure of progression due to severe adhesion (12 patients, 7%) and major vessel invasion (7 patients, 4%) were the two most frequent reasons for conversion. On multivariate analysis, age [Exp(β)=1.044, p=0.044] and pancreatic texture [Expa(β)=2.431, p=0.039) were found to be independent factors for predicting intraoperative conversion during LPD. In comparative analysis with the OPD group, the cPD group had a longer operation time (516.8 min vs. 449.9 min, p=0.001), higher rate of postoperative hemorrhage (12.1% vs. 0.85%, p=0.008), higher reoperation rate (9.1% vs. 0%, p=0.01), and higher cost (21886.4 USD vs. 17168.9 USD, p=0.018).

CONCLUSION

Intraoperative conversion during LPD can have an adverse clinical impact on the postoperative course following LPD. Appropriate patients selection and improvement of surgical techniques will be crucial for unnecessary intraoperative conversion and safe LPD.

Surgical outcomes are hampered after endoscopic ultrasonography-guided ethanol lavage and/or Taxol injection in cystic lesions of the pancreas

Backgrounds/Aims

Endoscopic ultrasonography-guided ethanol lavage and Taxol injection (EUS-ELTI) for pancreatic cystic lesions have been recently performed in some medical centers. The aim of this study was to optimize patient selection and analyze outcomes of patients who underwent surgeries after EUS-ELTI for pancreatic cystic lesions.

Methods

Among 310 patients who underwent EUS-ELTI between January 2007 and December 2014, 23 underwent surgeries after EUS-ELTI owing to incomplete treatment and/or adverse events. Surgical outcomes of patients who underwent surgeries after EUSELTI were evaluated. Clinical outcomes of patients who underwent surgeries after EUS-ELTI were then retrospectively compared with those of patients who underwent upfront surgery for left-sided pancreatic lesions without an EUS-ELTI procedure.

Results

The pathology revealed degenerated cysts in 12 patients, mucinous cyst neoplasms in five, neuroendocrine tumors in two, intraductal papillary mucinous neoplasm (IPMN) in one, solid pseudopapillary tumor in one, pancreatic ductal adenocarcinoma arising from an IPMN in one, and hepatoid carcinoma in one. Twelve patients underwent laparoscopic distal pancreatectomy and five patients underwent open distal pancreatectomy. When clinical outcomes were retrospectively compared between patients who underwent laparoscopic distal pancreatectomy after EUS-ELTI and those who did not receive an EUS-ELTI procedure, the spleen-preserving rate was 0% in the EUS-ELTI group and 61.7% (365/592) in the control group (p < 0.001).

Conclusions

Surgical outcomes are compromised after EUS-ELTI for cystic tumor of the pancreas. Further studies are needed to investigate the efficacy and safety of the EUS-ELTI procedure.

Preoperative risk stratification of postoperative pancreatic fistula: A risk-tree predictive model for pancreatoduodenectomy

BACKGROUND

Existing postoperative pancreatic fistula risk scores rely on intraoperative parameters, which limits their value in the preoperative setting. A preoperative predictive model to stratify the risk of developing postoperative pancreatic fistula before pancreatoduodenectomy was built and externally validated.

METHODS

A regression risk-tree model for preoperative postoperative pancreatic fistula risk stratification was developed in the Verona University Hospital training cohort using preoperative variables and then tested prospectively in a validation cohort of patients who underwent pancreatoduodenectomy at San Raffaele Hospital of Milan.

RESULTS

In the study period 566 (training cohort) and 456 (validation cohort) patients underwent pancreatoduodenectomy. In the multivariable analysis body mass index, radiographic main pancreatic duct diameter and American Society of Anesthesiologists score ≥3 were independently associated with postoperative pancreatic fistula. The regression tree analysis allocated patients into 3 preoperative risk groups with an 8%, 21%, and 32% risk of postoperative pancreatic fistula (all P < .01) based on main pancreatic duct diameter (≥ or <5 mm) and body mass index (≥ or <25). The 3 groups were labeled low, intermediate, and high risk and consisted of 206 (37%), 188 (33%), and 172 (30%) patients, respectively. The risk-tree was applied to validation cohort, successfully reproducing 3 risk groups with significantly different postoperative pancreatic fistula risks (all P < .01).

CONCLUSION

In candidates for pancreatoduodenectomy, the risk of postoperative pancreatic fistula can be quickly and accurately determined in the preoperative setting based on the body mass index and main pancreatic duct diameter at radiology. Preoperative risk stratification could potentially guide clinical decision-making, improve patient counseling and allow the establishment of personalized preoperative protocols.

Laparoscopic pancreaticoduodenectomy: a retrospective study of 200 cases and the optimization of the single-center learning curve

Background

Laparoscopic pancreaticoduodenectomy (LPD) is widely used in several centers. This study analyzed the postoperative complications rate curve, possible cause, and solution of LPD and open pancreaticoduodenectomy (OPD).

Methods

Between January 2015 and December 2019, the study included 213 and 204 patients undergoing OPD and LPD, respectively. Postoperative outcomes, complications, and complication risk, along with operation time were analyzed, and the learning curve was determined.

Results

The OPD group (378.7±8.98 min) had shorter operation time than the LPD group (402.5±7.12 min) (P=0.037). Blood loss was significantly lower in the LPD group (389.9±19.05 mL) than in the OPD group (530.1±33.55 mL) (P<0.001). The incidence of biliary-enteric anastomosis leakage was higher in the LPD group (2.9%) than in the OPD group (0.5%) (P=0.0495). The LPD group showed lower lung infection (7.4% vs. 17.4%, P=0.037), incision infection (1% vs. 8.5%, P<0.001), and anal exhaust time (3.35±0.07 vs. 4.05±0.07 days, P<0.001) than the OPD group. The biliary-enteric anastomosis leakage was strongly correlated with the pancreatic fistula (B/C) (R=0.6410), intraperitoneal infection (R=0.6126) and Clavien-Dindo Classification ≥3 (R=0.7403). According to the cumulative sum (CUSUM) curve, pancreatic fistula had a negative K value in 44 cases, biliary-enteric anastomosis leakage had a negative K value in 46 cases, and Clavien-Dindo Classification ≥3 had a negative K value in 40 cases. The learning curve for LPD has an inflection point in 86 cases.

Conclusions

LPD is safe and effective for patients with pancreatic cancer, and has a long learning curve and improved postoperative complications in 50 cases. This study’s results will help in reducing the complication rates of the first 50 consecutive cases of LPD.

Preoperative and intraoperative risk factors of postoperative pancreatic fistula after pancreaticoduodenectomy – systematic review and meta-analysis

Introduction: Postoperative pancreatic fistula (POPF) is a potentially life-threatening complication after pancreaticoduodenectomy (PD). It is observed when the amylase activity in the drain fluid exceeds three times the normal upper value. Grades B and C of POPF are considered as clinically relevant. Fistula might originate due to failure of healing of a pancreatic anastomosis or from raw pancreatic surface. Materials and methods: 18 retrospective and prospective studies published between 2015 and 2020 were included in this meta-analysis. Total number of patients was 5836. To investigate potential risk factors associated with the occurrence of POPF, odds ratios (OR) with 95% confidence intervals (CI) were calculated. To compare discontinuous data, mean differences (MD) were calculated. Results: 13 factors were divided into preoperative and intraoperative groups. Male sex, higher BMI, soft pancreatic texture and small pancreatic duct were considered as significant risk factors while vascular resection lowered the risk of development pancreatic fistula. Discussion: It is considered that the development of POPF is associated with intrapancreatic fat. More severe infiltration with fat tissue is responsible for soft texture of the gland, while higher BMI is one of the risk factors of increased pancreatic fat. On the contrary, diabetes is associated with fibrotic pancreas which could lower the risk of developing POPF.

Postoperative day 1 combination of serum C-reactive protein and drain amylase values predicts risks of clinically relevant pancreatic fistula. The "90-1000" score

BACKGROUND

Several scoring systems predict risks of clinically relevant postoperative pancreatic fistula after pancreatectomy, but none have emerged as the gold standard. This study aimed to evaluate the accuracy of postoperative day 1 drain amylase and serum C-reactive protein levels in predicting clinically relevant postoperative pancreatic fistula compared with intraoperative pancreatic characteristics.

METHODS

Patients who underwent pancreatectomy between 2017 and 2019 were included prospectively. Cutoff values were determined using receiver operating characteristic curves, and a score combining postoperative day 1 drain amylase and serum C-reactive protein was tested in a multivariate logistic regression model to evaluate clinically relevant postoperative pancreatic fistula risk.

RESULTS

A total of 274 pancreatic resections (182 pancreaticoduodenectomies and 92 distal pancreatectomies) were included. The pancreatic gland texture was "soft" in 47.8% (n = 131), and 55.8% (n = 153) had a small size main pancreatic duct (≤3 mm). Clinically relevant postoperative pancreatic fistula occurred in 58 patients (21.2%). Drain amylase ≥1,000 UI/L and serum C-reactive protein ≥90 mg/L were identified as the optimal cutoffs to predict clinically relevant postoperative pancreatic fistula. On multivariate analysis these cutoffs were independent predictors of clinically relevant postoperative pancreatic fistula after both pancreaticoduodenectomies (drain amylase: P < .001, serum C-reactive protein: P = .006) and distal pancreatectomies (drain amylase: P = .009, serum C-reactive protein: P = .001). The postoperative day 1 "90-1000" model, a 2-value score relying on these cutoffs, significantly (P < .001) outperformed intraoperative pancreatic parenchymal characteristics in predicting clinically relevant postoperative pancreatic fistula after both pancreaticoduodenectomies and distal pancreatectomies. A postoperative day 1 "90-1000" score = 0 had a negative predictive value of 97% and 94%, respectively, after pancreaticoduodenectomy and distal pancreatectomies.

CONCLUSION

A combined score relying on postoperative day 1 values of drain amylase and serum C-reactive protein levels was accurate in predicting risks of clinically relevant postoperative pancreatic fistula after pancreatectomy.

The use of comprehensive complication Index® in pancreatic surgery: a comparison with the Clavien-Dindo system in a high volume center

BACKGROUND

The Clavien-Dindo classification (CDC) system and Comprehensive Complication Index (CCI®) are both widely used methods for reporting the burden of postoperative complications. This study aimed to compare the accuracy of the CDC and CCI® in predicting outcomes associated with pancreatic surgery.

METHODS

The CCI® and CDC were applied to 668 patients who underwent pancreatic resection. Length of postoperative stay (LOS) was chosen as the primary outcome variable. The comparison between CCI® and CDC was made with the Spearman test, reporting þs with standard error (SE) and logistic regression, reporting the Odds Ratio (OR) and Area Under the Curve with SE.

RESULTS

The median value with the interquartile range (IQR) of CCI® was 20.9 (0-29.6). Both CCI® (þs = 0.609) and CDC (0.590) were significantly (P < 0.001) correlated to LOS. CCI (OR 1.056 and OR 1.052) and CDC (OR 1.978, and OR 1.994) predicted (P < 0.001) LOS over the median and 75th percentile. The accuracy of CCI® was superior to CDC for LOS over 50th (0.785 vs. 0.740; P = 0.004) and over 75th (0.835 vs. 0.761; P < 0.001) percentile.

CONCLUSION

The accuracy of CCI® in measuring the complicated postoperative course was superior to CDC, correctly classifying eight patients every ten tested.

Blumgart Anastomosis After Pancreaticoduodenectomy. A Comprehensive Systematic Review, Meta-Analysis, and Meta-Regression

BACKGROUND

The superiority of Blumgart anastomosis (BA) over non-BA duct to mucosa (non-BA DtoM) still remains under debate.

METHODS

We performed a systematic search of studies comparing BA to non-BA DtoM. The primary endpoint was CR-POPF. Postoperative morbidity and mortality, post-pancreatectomy hemorrhage (PPH), delayed gastric emptying (DGE), reoperation rate, and length of stay (LOS) were evaluated as secondary endpoints. The meta-analysis was carried out using random effect. The results were reported as odds ratio (OR), risk difference (RD), weighted mean difference (WMD), and number needed to treat (NNT).

RESULTS

Twelve papers involving 2368 patients: 1075 BA and 1193 non-BA DtoM were included. Regarding the primary endpoint, BA was superior to non-BA DtoM (RD = 0.10; 95% CI: -0.16 to -0.04; NNT = 9). The multivariate ORs' meta-analysis confirmed BA's protective role (OR 0.26; 95% CI: 0.09 to 0.79). BA was superior to DtoM regarding overall morbidity (RD = -0.10; 95% CI: -0.18 to -0.02; NNT = 25), PPH (RD = -0.03; 95% CI -0.06 to -0.01; NNT = 33), and LOS (- 4.2 days; -7.1 to -1.2 95% CI).

CONCLUSION

BA seems to be superior to non-BA DtoM in avoiding CR-POPF.

The comparation of short-term outcome between laparoscopic and open pancreaticoduodenectomy: a propensity score matching analysis

Pancreaticoduodenectomy (PD) is one of the most complex and delicate operations in abdominal surgery. With the development of laparoscopic techniques, more and more pancreatic experts have become skilled in laparoscopic pancreaticoduodenectomy (LPD). However, the short-term efficacy of LPD compared to open pancreaticoduodenectomy (OPD) remains unclear. Here, we performed a propensity score matching study aiming to compare the short outcomes of patients who underwent LPD or OPD after the learning curve and established a risk model of pancreatic fistula. The data of 346 patients who had OPD or LPD from July 2015 to January 2020 were retrieved. After a 1:1 matching, 224 patients remained. The operation time was significantly longer (P = 0.001) but the amount of bleeding was significantly lower (P = 0.001) in the LPD group than in the OPD group. Patients in LPD group had fewer blood transfusions (P = 0.002) than those in OPD group. More lymph nodes (P < 0.001) were dissected in LPD group. The rate of grade B/C pancreatic fistula was significantly higher in the LPD group than in the OPD group (16.1% vs. 6.3%, P = 0.002). By multi variate Logistic regression analysis, we identified pancreatic tumor, malignancy and low body mass index were risk factors of Grade B/C pancreatic fistula after PD operation. Then, we developed a Grade B/C pancreatic fistula nomogram with the risk factors. The C-index of the nomogram was 0.836 (95% CI 0.762-0.910). In conclusion, LPD could be technically feasible, get less trauma and achieve similar short-term outcome as compared with OPD.

Comparison of Blumgart Anastomosis with Duct-to-Mucosa Anastomosis and Invagination Pancreaticojejunostomy After Pancreaticoduodenectomy: A Single-Center Propensity Score Matching Analysis

BACKGROUND

The Blumgart anastomosis is a method of pancreaticojejunostomy after pancreaticoduodenectomy (PD) which combines the principle of duct-to-mucosa anastomosis with an invagination technique of the pancreas.

METHODS

Retrospective study involving consecutive patients who underwent pancreaticoduodenectomy for pancreatic head cancer. Data predictive of pancreatic fistula and postoperative outcomes were collected. The patients were divided into three groups and were compared based on the type of pancreatic anastomosis performed: Blumgart anastomosis (BA), duct-to-mucosa anastomosis (DtoM), and invagination pancreaticojejunostomy (PJ). The primary endpoint was to determine the occurrence of clinically relevant postoperative pancreatic fistula (CR-POPF). The secondary endpoints were to determine whether postoperative pancreatic fistula grade C (POPF C) and/or severe complications occurred as well as to determine the reoperation rate and 30- and 90-day mortality. A propensity score matching analysis was used.

RESULTS

Using propensity score matching (PSM), the occurrence of CR-POPF was not significantly different between the BA (21.6%) and the other pancreatic anastomoses (all 31.1%, DtoM = 27.0%; PJ = 35.1%). However, the BA significantly reduced (1) severe complications (0 versus 35.1%; P < 0.001) and 90-day mortality (0% versus 12.2%; P = 0.028) with respect to all anastomoses; (2) severe complications (0% versus 29.7%; P < 0.001), POPF grade C (0% versus 16.2%; P = 0.025), and reoperation (2.7% versus 16.2%; P = 0.056) with respect to DtoM; and (3) severe complications (0% versus 40.5%; P < 0.001) and 90-day mortality (0% versus 13.5%; P = 0.054) with respect to PJ.

CONCLUSIONS

Applying the PSM analysis for the first time, the present study seemed to suggest that the BA succeeded in minimizing severe complications after PD.

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.

Relation of computed tomography features of the pancreatic tissue and development of pancreatic fistula after pancreaticoduodenectomy

BACKGROUND

Pancreatic density and steatosis detected in pre-operative computed tomography (CT) may be a risk factor for PF development after pancreatoduodenectomy (PD). There is insufficient data available on the relationship between PF and atherosclerosis in pancreatic vasculature of pancreatitis. This study aims to investigate whether PF development in patients undergoing PD can be predicted by preoperative CT findings.

MATERIAL-METHOD

Pancreas and spleen densities were measured on non-contrast CT images and pancreatic index (PI) was calculated to detect pancreatic steatosis. Pancreatic density and Wirsung diameter (WD) were measured on portal venous phase. Pancreatic fistulae were identified as biochemical leak (BL), grade B and grade C using ISGPF classification. The findings were compared between the fistula and non-fistula groups and ISGPF subgroups.

RESULTS

Of 148 patients, PF was detected on 31 (20.9%). In PF group, mean pancreatic density and PI were significantly lower than non-PF group, while pancreatic steatosis was detected at a higher rate. The WD was significantly narrower in the PF group. No significant relationship was found between the development of PF and the findings of atherosclerosis in the CT and SMA or acute pancreatitis. There was no significant difference between the PF subgroups for pancreas density.

CONCLUSION

In preoperative CT examinations, measuring the pancreatic density, PI index and WD can be used as a noninvasive quantitative method to predict the possibility of postoperative PF development.

Pancreatic ultrasound elastography is not useful to predict the risk of pancreatic fistulas after pancreatic resection

The clinical usefulness of pancreatic elastography (PE) in the assessment of the pancreatic texture before pancreatic resection still remains uncertain. The aims are: to evaluate the value of pancreatic stiffness in both healthy volunteers and patients affected by pancreatic tumor; to evaluate the ability of PE in predicting clinically relevant postoperative pancreatic fistula (CR-POPF). Pancreatic stiffness of healthy subjects was compared with those of pancreatic tumors measuring shear wave velocity (SWV). In the last group, the ability of preoperative SWV in predicting CR-POPF was evaluated using linear regression. Ninety subjects were consecutively enrolled. No difference was found in SWV in the two groups (1.33 ± 0.31 vs 1.26 ± 0.30, p = 0.337). Multivariate analyses showed that male gender was associated with a softer pancreas (OR 0.74, CI 0.55-0.98, p = 0.035). In the 45 patients suitable for a secondary endpoint, the presence of soft pancreas assessed by surgeon's palpation (OR 61.21; CI 2.14- > 1000; p = 0.016) and preoperative risk score (OR 1.72; CI 1.01-2.96; p = 0.049) was predictors of CR-POPF. SWV showed a trend in predicting CR-POPF. The pancreatic stiffness far to the pancreatic neoplasm is the same as healthy controls. SWV showed a trend in predicting CR-POPF but the clinical utility is limited.

The Yonsei experience of 104 laparoscopic pancreaticoduodenectomies: a propensity score-matched analysis with open pancreaticoduodenectomy

BACKGROUND

With continued technical advances in surgical instruments and growing expertise, several surgeons have performed laparoscopic pylorus preserving pancreaticoduodenectomy (L-PPPD) safely with good results, and the laparoscopic approach is being performed more frequently. We performed over 100 cases of L-PPPD and compared their outcomes to those of open PPPD (O-PPPD) using the large sample size. The aim of the present study was to evaluate the safety and feasibility of L-PPPD compared with O-PPPD.

METHODS

From September 2012 to June 2017, PPPD was performed for 217 patients at Yonsei University Severance Hospital by a single surgeon. Patients were divided into two groups: those who underwent O-PPPD (n = 113) and those who underwent L-PPPD (n = 104). We performed a 1:1 propensity score-matched (PSM) analysis and retrospectively analyzed the demographic and surgical outcomes. We also reviewed all previous studies of more than 100 cases.

RESULTS

The L-PPPD group had lesser intraoperative blood loss than the O-PPPD group (548.1 ml vs. 244.7 ml; p < 0.001). Both groups showed similar rates of negative resection margins (99.1% vs. 96.2%; p = 0.196). Overall complication rates did not differ significantly between O-PPPD and L-PPPD (39.8% vs. 35.6%; p = 0.519). The clinically relevant postoperative pancreatic fistula (POPF) rates in the O-PPPD and L-PPPD groups were 18.8% and 13.5%, respectively (p = 0.311). There was no difference in 30- and 90-day mortality rates between the two groups (p = 0.479). Similar results were obtained after PSM analysis.

CONCLUSIONS

L-PPPD can be a good alternative option for well-selected patients with periampullary lesions requiring PPPD.

Validation of original and alternative fistula risk scores in postoperative pancreatic fistula

Background

In 2013, the fistula risk score (FRS) was developed to assess the risk of clinically relevant postoperative pancreatic fistula (CR‐POPF). In 2017, the alternative FRS (a‐FRS) was proposed. The purpose of this study was to validate the original FRS (o‐FRS) and a‐FRS for CR‐POPF in pancreaticoduodenectomy (PD).

Methods

From January 2007 to December 2016, 1,771 patients underwent PD for periampullary cancers. POPF was defined and classified according to the 2016 International Study Group for Pancreatic Fistula. All data were reviewed retrospectively.

Results

Pathologic diagnosis other than ductal adenocarcinoma (P < 0.001), pancreas duct diameter (P < 0.001), and body mass index (P < 0.001) were independent risk factors for CR‐POPF. Pancreatic texture (P = 0.534) and estimated blood loss (P = 0.827) were not associated with CR‐POPF. The CR‐POPF incidence increased with increasing o‐FRS score (P < 0.001), and also increased statistically significantly with increasing a‐FRS in the higher risk group (P < 0.001). However, the correlations differed. The area under the curve was 0.629 for o‐FRS and 0.622 for a‐FRS.

Conclusions

Both o‐FRS and a‐FRS might reflect CR‐POPF incidence, but some risk factors had no or low statistical significance. Further research is needed to revise the FRS.

Preoperative risk evaluation for pancreatic fistula after pancreaticoduodenectomy

BACKGROUND

Pancreatic fistula remains common, with limited ability to risk stratify patients preoperatively. The objective of this study was to identify risk factors for clinically-relevant postoperative pancreatic fistula (CR-POPF) that are routinely available in the preoperative setting.

METHODS

Preoperatively available variables for all pancreaticoduodenectomies from 2014-2017 were examined using a national clinical registry. The cohort was separated into risk factor identification and internal validation subgroups.

RESULTS

Among 15 033 pancreaticoduodenectomies, the CR-POPF rate was 16.7%. CR-POPF was more likely in patients that were male (odds ratio [OR], 1.51), obese (body mass index [BMI] > 30, OR, 1.97), had minimal preoperative weight loss (OR, 1.25), had a nondilated pancreatic duct (OR, 1.81), did not have diabetes, (OR, 1.80), did not receive neoadjuvant therapy (OR, 1.78), had no evidence of biliary obstruction (OR, 1.18), or had nonadenocarcinoma pathology (OR, 1.96; all P < 0.01). Patients with three or fewer risk factors had a CR-POPF rate of 7.1%, while those with six or more risk factors had a CR-POPF rate of 26.3% (P < 0.001).

CONCLUSION

Preoperative CR-POPF risk evaluation could be a useful tool in patient counseling and surgical planning, and risk may allow for more well-informed decisions regarding perioperative management, including enhanced recovery protocols and use of somatostatin analogs.

Effect of Blumgart anastomosis in reducing the incidence rate of pancreatic fistula after pancreatoduodenectomy

BACKGROUND

Pancreatic fistula is one of the most serious complications after pancreatoduodenectomy for treating any lesions at the pancreatic head. For years, surgeons have tried various methods to reduce its incidence.

AIM

To investigate and emphasize the clinical outcomes of Blumgart anastomosis compared with traditional anastomosis in reducing postoperative pancreatic fistula.

METHODS

In this observational study, a retrospective analysis of 291 patients who underwent pancreatoduodenectomy, including Blumgart anastomosis (201 patients) and traditional embedded pancreaticojejunostomy (90 patients), was performed in our hospital. The preoperative and perioperative courses and long-term follow-up status were analyzed to compare the advantages and disadvantages of the two methods. Moreover, 291 patients were then separated by the severity of postoperative pancreatic fistula, and two methods of pancreaticojejunostomy were compared to detect the features of different anastomosis. Six experienced surgeons were involved and all of them were proficient in both surgical techniques.

RESULTS

The characteristics of the patients in the two groups showed no significant differences, nor the preoperative information and pathological diagnoses. The operative time was significantly shorter in the Blumgart group (343.5 ± 23.0 vs 450.0 ± 40.1 min, P = 0.028), as well as the duration of pancreaticojejunostomy drainage tube placement and postoperative hospital stay (12.7 ± 0.9 d vs 17.4 ± 1.8 d, P = 0.031; and 21.9 ± 1.3 d vs 28.9 ± 1.3 d, P = 0.020, respectively). The overall complications after surgery were much less in the Blumgart group than in the embedded group (11.9% vs 26.7%, P = 0.002). Patients who underwent Blumgart anastomosis would suffer less from severe pancreatic fistula (71.9% vs 50.0%, P = 0.006), and this pancreaticojejunostomy procedure did not have worse influences on long-term complications and life quality. Thus, Blumgart anastomosis is a feasible pancreaticojejunostomy procedure in pancreatoduodenectomy surgery. It is safe in causing less postoperative complications, especially pancreatic fistula, and thus shortens the hospitalization duration.

CONCLUSION

Surgical method should be a key factor in reducing pancreatic fistula, and Blumgart anastomosis needs further promotion.

Systematic review and meta-analysis of postoperative pancreatic fistula rates using the updated 2016 International Study Group Pancreatic Fistula definition in patients undergoing pancreatic resection with soft and hard pancreatic texture

BACKGROUND

In 2016, the International Study Group of Pancreatic Fistula (ISGPS) proposed an updated definition for postoperative pancreatic fistula (POPF). Pancreas texture (PT) is an established risk factor of POPF. The definition of soft vs. hard texture, however, remains elusive.

METHODS

A systematic search was performed to identify PT definitions and a meta-analysis linking POPF to PT using the updated ISGPS definition.

RESULTS

122 studies including 22 376 patients were identified. Definition criteria for PT varied among studies and most classified PT in hard and soft based on intraoperative subjective assessment. The total POPF rate (pooled grades B and C) after pancreatoduodenectomy was 14.5% (n = 10 395) and 15.5% (n = 3767) after distal pancreatectomy. In pancreatoduodenectomy, POPF rate was higher in soft compared to hard pancreas (RR, 4.4, 3.3 to 6.1; p < 0.001; n = 6393), where PT grouped as soft and hard. No data were available for intermediate PT.

CONCLUSION

The reported POPF rates may be used in planning future prospective studies. A widely accepted definition of PT is lacking and a correlation with the risk of POPF is based on subjective evaluation, which is still acceptable. Classification of PT into 2-groups is more reasonable than classification into 3-groups.

Predictive value of drain pancreatic amylase concentration for postoperative pancreatic fistula on postoperative day 1 after pancreatic resection: An updated meta-analysis

BACKGROUND

Postoperative pancreatic fistula (POPF) is a potentially fatal complication following pancreaticoduodenectomy. Early prediction and exclusion of POPF may be highly advantageous to enhance patient outcomes, and accelerate recovery. In this meta-analysis, we sought to assess the prediction of drain pancreatic amylase concentration on postoperative day 1 (DPA1) for POPF.

METHODS

By searching online databases up to April 2018, all researches mentioned DPA1 for detecting POPF were analyzed. STATA 12.0 was used to analyze pooled predictive parameters.

RESULTS

Seventeen studies were finally analyzed including 4676 patients in total. The pooled sensitivity and specificity of DPA1 were respectively 0.85 (95% CI: 0.71, 0.93), 0.80 (95% CI: 0.74, 0.85) to predict overall POPF, and 0.70 (95% CI: 0.53, 0.82), 0.88 (95% CI: 0.86, 0.90) to predict CR-POPF. If pretest probability was 50%, corresponding post-test (+) were respectively 81%, 86% for overall POPF and CR-POPF when DPA1 was above cutoffs, while the post-test (-) were respectively 16%, 26% when DPA1 was under cutoffs. In subgroup analysis, sensitivities of cutoff >5000 group, 1000< cutoff <5000 group, and cutoff <1000 group were respectively 0.65 (0.43-0.82), 0.82 (0.71-0.89), 0.87 (0.78-0.92); and specificities were respectively 0.88 (0.83-0.92), 0.83 (0.77-0.88), 0.71 (0.62-0.79). Positive LR was 5.5 (3.4-8.8), 4.8 (3.4-6.7), and 3.0 (2.3-4.0) respectively. Negative LR was 0.40 (0.22-0.72), 0.22 (0.13-0.37), and 0.19 (0.11-0.32) respectively.

CONCLUSION

DPA1, which has good sensitivity and specificity, is useful for predicting overall POPF and CR-POPF, according to the present studies. Meanwhile, it should be cautious to apply because there is a wide range in cutoffs between different studies.

Application of a novel embeddedness-like pancreaticojejunostomy anastomosis technique used in pancreaticoduodenectomy

Optimized pancreaticojejunostomy anastomosis was used to investigate the effects on the incidence rate of postoperative complications in pancreaticoduodenectomy. The data of 250 patients who underwent pancreaticoduodenectomy between August 2011 and December 2015 were analyzed; all surgery was performed by a single team. The first 100 surgeries were performed using traditional pancreaticojejunostomy anastomosis, whereas the next 150 patients underwent novel pancreaticojejunostomy anastomosis (the experimental group). General information, disease status and the occurrence rate of postoperative complications [postoperative pancreatic fistula (POPF), biliary leakage, delayed gastric emptying, bleeding and mortality] within 30 days of surgery were observed. In the first group, 56 patients had POPF (56%), the proportion of grades A, B and C was 44% (n=44), 9% (n=9) and 3% (n=3), respectively; in the experimental group, 30 patients had POPF (20%), the proportion of grades A, B and C was 14.67% (n=22), 5.33% (n=8) and 0%, respectively. Furthermore, in the experimental group, none of the patients exhibited postoperative bleeding or succumbed during surgery. The application of the novel embeddedness-like pancreaticojejunostomy anastomosis technique in pancreaticoduodenectomy was safe and effective, and may reduce the incidence of POPF in future.