What should we trust to define, predict and assess pancreatic fistula after pancreatectomy?

Evaluation of pancreatic chymotrypsin activity for on-site prediction of clinically relevant postoperative pancreatic fistula

OBJECTIVES

Although the risk of complications due to postoperative pancreatic fistula (POPF) have been evaluated based on the amylase level in drained ascitic fluid, this method has much room for improvement regarding diagnostic accuracy and facility of the measurement. This study aimed to investigate the clinical value of measuring pancreatic chymotrypsin activity for rapid and accurate prediction of POPF after pancreaticoduodenectomy.

METHODS

In 52 consecutive patients undergoing pancreaticoduodenectomy, the chymotrypsin activity in pancreatic juice was measured by calculating the increase in fluorescence intensity during the first 5 min after activation with an enzyme-activatable fluorophore. The predictive value for clinically relevant POPF (CR-POPF) was compared between this technique and the conventional method based on the amylase level.

RESULTS

According to receiver operating characteristic analyses, pancreatic chymotrypsin activity on postoperative day (POD) 3 measured with a multiplate reader had the highest predictive value for CR-POPF (area under the curve [AUC], 0.752; P < 0.001), yielding 77.8 % sensitivity and 68.8 % specificity. The AUC and sensitivity/specificity of the amylase level in ascitic fluid on POD 3 were 0.695 (P = 0.053) and 77.8 %/41.2 %, respectively. Multivariable analysis identified high pancreatic chymotrypsin activity on POD 3 as an independent risk factor for CR-POPF. Measurement of pancreatic chymotrypsin activity with a prototype portable fluorescence photometer could significantly predict CR-POPF (AUC, 0.731; P = 0.010).

CONCLUSION

Measurement of pancreatic chymotrypsin activity enabled accurate and rapid prediction of CR-POPF after pancreaticoduodenectomy. This can help surgeons to implement appropriate drain management at the patient's bedside without delay.

Serum Interleukin-6 as a Biomarker for Early Prediction of Post-Operative Infectious Complications After Elective Pancreatectomy

Background: To investigate whether interleukin (IL)-6 could predict the post-operative complications of elective pancreatectomy early. Patients and Methods: Overall, 122 patients who underwent elective pancreatectomy from June 2020 to May 2021 in our hospital were enrolled. Interleukin-6 was measured on the day before and at six hours after surgery, and on post-operative day one, three, and five. The associations between IL-6 level and post-operative complications were analyzed, and the predictive value of IL-6 for complications was assessed. Results: Sixty-three patients developed post-operative complications. Higher IL-6 was observed in patients with post-operative complications on post-operative day one, post-operative day three, and post-operative day five, with odd ratios of 1.43, 1.68, and 2.54 (p = 0.01, p = 0.01, and p = 0.01), respectively. These trends were also observed in patients with infectious complications preoperatively, on post-operative day one, post-operative day three, and post-operative day five, with ORs of 2.46, 1.95, 2.01, and 2.49 (p = 0.00, 0.00, 0.01, 0.00) respectively. Multivariate regression revealed that IL-6 is the only predictor for infectious complications on post-operative day one (p = 0.016). Based on the optimal cutoffs, pre-operative IL-6, IL-6 on post-operative day one and post-operative day three for predicting infectious complications yielded area under the curve (AUC) of 0.73, 0.70, and 0.70, with high negative predictive value of 82.7%, 92.2%, and of 91.3%, respectively. Conclusions: This study validated the early predictive value of IL-6 on infectious complications after pancreatectomy. Because of the performance of serum IL-6 in predicting infectious complications and high NPV, we endorse that IL-6 could be a potential biomarker for early prediction and antibiotic optimization after pancreatectomy.

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.

Management of postoperative pancreatic fistula after pancreaticoduodenectomy

A postoperative pancreatic fistula (POPF) is the main complication after cephalic pancreaticoduodenectomy (CPD). Unlike its prevention, the curative management of POPFs has long been poorly codified. This review seeks best practices for managing POPFs after CPD. The diagnosis of a POPF is based on two signs: (i) an amylase level in drained fluid more than 3 times the upper limit of the blood amylase level; and (ii) an abnormal clinical course. In the standardised definition of the International Study Group of Pancreatic Surgery, a purely biochemical fistula is no longer counted as a POPF and is treated by gradual withdrawal of the drain over at most 3 weeks. POPF risk can be scored using pre- and intraoperative clinical criteria, many of which are related to the quality of the pancreatic parenchyma and are common to several scoring systems. The prognostic value of these scores can be improved as early as Day 1 by amylase assays in blood and drained fluid. Recent literature, including in particular the Dutch randomised trial PORSCH, argues for early systematic detection of a POPF (periodic assays, CT-scan with injection indicated on standardised clinical and biological criteria plus an opinion from a pancreatic surgeon), for rapid minimally invasive treatment of collections (percutaneous drainage, antibiotic therapy indicated on standardised criteria) to forestall severe septic and/or haemorrhagic forms, and for the swift withdrawal of abdominal drains when the risk of a POPF is theoretically low and evolution is favourable. A haemorrhage occurring after Day 1 always requires CT angiography with arterial time and monitoring in intensive care. Minimally invasive treatment of a POPF (radiologically-guided percutaneous drainage or, more rarely, endoscopic drainage, arterial embolisation) should be preferred as first-line treatment. The addition of artificial nutrition (enteral via a nasogastric or nasojejunal tube, or parenteral) is most often useful. If minimally invasive treatment fails, then reintervention is indicated, preserving the remaining pancreas if possible, but the expected mortality is higher.

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.

Postoperative pancreatic fistula affects recurrence-free survival of pancreatic cancer patients

PURPOSE

Postoperative pancreatic fistula (POPF) with reported incidence rates up to 45% contributes substantially to overall morbidity. In this study, we conducted a retrospective evaluation of POPF along with its potential perioperative clinical risk factors and its effect on tumor recurrence.

METHODS

Clinical data on patients who had received pancreatoduodenectomy (PD), distal pancreatectomy (DP), or duodenum-preserving pancreatic head resection (DPPHR) were prospectively collected between 2007 and 2016. A Picrosirius red staining score was developed to enable morphological classification of the resection margin of the pancreatic stump. The primary end point was the development of major complications. The secondary end points were overall and recurrence-free survival.

RESULTS

340 patients underwent pancreatic resection including 222 (65.3%) PD, 87 (25.6%) DP, and 31 (9.1%) DPPHR. Postoperative major complications were observed in 74 patients (21.8%). In multivariable logistic regression analysis, POPF correlated with body mass index (BMI) (p = 0.025), prolonged stay in hospital (p<0.001), high Picrosirius red staining score (p = 0.049), and elevated postoperative levels of amylase or lipase in drain fluid (p≤0.001). Multivariable Cox regression analysis identified UICC stage (p<0.001), tumor differentiation (p<0.001), depth of invasion (p = 0.001), nodal invasion (p = 0.001), and the incidence of POPF grades B and C (p = 0.006) as independent prognostic markers of recurrence-free survival.

CONCLUSION

Besides the known clinicopathological risk factors BMI and amylase in the drain fluid, the incidence of POPF correlates with high Picrosirius red staining score in the resection margins of the pancreatic stumps of curatively resected pancreatic ductal adenocarcinoma (PDAC). Furthermore, clinically relevant POPF seems to be a prognostic factor for tumor recurrence in PDAC.