Comparison of preoperative CT-based imaging parameters to predict postoperative pancreatic fistula

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.

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.

Preoperative Computed Tomography Imaging of the Pancreas Identifying Predictive Factors for the Progression of Grade A, or Biochemical Leak, to Grade B Postoperative Pancreatic Fistula Following Pancreaticoduodenectomy: A Retrospective Study

Background

This retrospective study aimed to identify the predictive factors for the progression of grade A, or early biochemical leak, to grade B postoperative pancreatic fistula (POPF) following pancreaticoduodenectomy using preoperative computed tomography (CT) imaging of the pancreas.

Material/Methods

A total of 156 patients were analyzed retrospectively. Biochemical leakage occurred in 60 patients, who were divided into POPF progression and non-POPF progression groups. Perioperative parameters were collected. Univariate analysis and multivariate logistic regression analysis were done. For the parameters with statistical significance, the area under the curve (AUC) was calculated if possible and the predictive value was assessed.

Results

Univariate analysis showed that main pancreatic duct diameter, postoperative complications (except POPF), prothrombin time (PT) and serum albumin on postoperative day 3, and pancreatic CT value were risk factors of POPF (P<0.05). Multivariate analysis showed that serum albumin and PT on postoperative day 3 and pancreatic CT value were independent risk factors of POPF (P<0.05). Lower postoperative albumin, lower pancreatic CT value, and longer PT were associated with a higher risk of POPF (P<0.05). The AUC of CT value was 0.808. CT value thresholds of 42.5 Hounsfield units (HU) and 41.5 HU were tied for the highest predictive performance, with Youden indices of 0.486 for both, and sensitivity of 79% and 71%, and specificity of 69% and 78%, respectively.

Conclusions

Preoperative laboratory investigations and CT imaging of the pancreas may identify factors associated with early biochemical leakage progressing to grade B POPF following pancreaticoduodenectomy.

Predictive factors of postoperative pancreatic fistula after laparoscopic pancreatoduodenectomy

Background

Clinically relevant postoperative pancreatic fistula (CR-POPF) continues to be a major contributor to morbidity after pancreaticoduodenectomy (PD), but it remains unclear what risk factors can precisely predict the development of CR-POPF after laparoscopic pancreatoduodenectomy (LPD). We thus aimed to identify the risk factors for predicting CR-POPF after LPD.

Methods

A total of 388 consecutive patients who underwent LPD at our institution between July 2014 and December 2018 were identified. All data, including pre-, intra-, and postoperative risk factors associated with CR-POPF defined by the International Study Group of Pancreatic Fistula, were collected retrospectively. To evaluate the predictive performance of the risk factor models, areas under the receiver operating characteristic curve (ROC) were determined.

Results

CR-POPF was observed in 31 patients (8.0%) with significant association observed with body mass index (BMI), visceral fat area (VFA), subcutaneous fat area (SFA), total fat area (TFA), intra-abdominal fat thickness, main pancreatic duct width, soft pancreatic texture, operative time, underlying pathology, and albumin (Alb) on postoperative days (POD) 1­–3. Multivariate analyses revealed that VFA >82 cm² [odds ratio (OR) =11.088; P=0.029], main pancreatic duct width <3 mm (OR =7.701; P=0.001), soft pancreatic texture (OR =12.543; P=0.022), and operative time >320 min (OR =6.061; P<0.001) were independent risk factors for CR-POPF after LPD. Areas under the ROC curve (AUC) analysis revealed the pancreatic texture was the strongest single predictor (AUC =0.854) of CR-POPF, and pancreatic texture + pancreatic duct width was the best two-predictor model (AUC =0.904). Meanwhile, our findings indicated an association between the TFA >221 cm² (OR =8.637; P=0.001) and VFA >82 cm² (OR =7.009; P<0.001) with soft pancreatic texture.

Conclusions

Soft pancreatic texture, VFA >82 cm², main pancreatic duct width <3 mm, and operative time >320 min were independent predictive risk factors of CR-POPF for LPD.

A deep pancreas is a novel predictor of pancreatic fistula after pancreaticoduodenectomy in patients with a nondilated main pancreatic duct

BACKGROUND

We investigated the risk factors for clinically relevant postoperative pancreatic fistula after pancreaticoduodenectomy in patients with a nondilated main pancreatic duct.

METHODS

We investigated a total of 354 patients who underwent pancreaticoduodenectomy. The diameter of the main pancreatic duct, the shortest distance from the body surface to the pancreas (the pancreatic depth), and the computed tomography attenuation index (the difference between the pancreatic and splenic computed tomography attenuation) were measured in preoperative computed tomography.

RESULTS

One hundred eighty-one (51.1%) patients had a nondilated main pancreatic duct, and 50 (27.6%) of the 181 patients with a nondilated main pancreatic duct developed a clinically relevant postoperative pancreatic fistula. Univariate analyses revealed that the calculated body mass index (≥21.8 kg/m²) (P = .004), deep pancreas (pancreatic depth ≥51.2 mm) (P = .001), and low computed tomography attenuation index (≤-3.8 Hounsfield units) (P = .02) were significant risk factors for clinically relevant postoperative pancreatic fistula. The multivariate logistic regression analysis revealed that deep pancreas (odds ratio 2.370; 95% confidence interval 1.0019-5.590; P = .049) was an independent risk factor for clinically relevant postoperative pancreatic fistula. Among patients with a nondilated main pancreatic duct, deep pancreas (in comparison to patients without deep pancreas) was associated with male sex (72.7% vs 54.9%; P = .016), higher body mass index (22.5 kg/m² vs 19.6 kg/m²; P < .001), a history of diabetes mellitus (24.5% vs 8.5%; P = .006), a lower computed tomography attenuation index (-9.6 Hounsfield units vs -4.6 Hounsfield units; P = .007), a longer operative time (454 minutes vs 420 minutes; P = .007), and a higher volume of intraoperative blood loss (723 mL vs 500 mL; P < .001), respectively.

CONCLUSION

Deep pancreas may be an important parameter associated with significant risk factors for clinically relevant postoperative pancreatic fistula after pancreaticoduodenectomy in patients with a nondilated main pancreatic duct.

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.

Pancreatic Fat and Body Composition Measurements by Computed Tomography are Associated with Pancreatic Fistula After Pancreatectomy

OBJECTIVES

Postoperative pancreatic fistula (POPF) is the most threatening complication after pancreatectomy. This study aimed to directly assess pancreatic fatty infiltration with preoperative computed tomography (CT) imaging and to investigate whether a preoperative analysis of patient variables, including CT characteristics and clinical factors, can predict POPF.

METHODS

We enrolled 150 consecutive patients who underwent curative pancreatectomy. Radiographic factors, including pancreatic fat volume, were measured using preoperative CT imaging and the predictive factors were explored using univariate and multivariate analyses.

RESULTS

POPF developed in 30 patients (20.0%). The ratio of pancreatic fat (RPF) ≥ 4.83% was associated with a risk of POPF, high body mass index (BMI), and obese body habitus. Patients with POPF were significantly more likely to have high BMI (≥ 25 kg/m²), obese body habitus, and an RPF ≥ 4.83% than patients without POPF. In the multivariate analysis, visceral fat area/skeletal muscle index (VFA/SMI) ≥ 1.94 (odds ratio [OR] 4.28, 95% confidence interval [CI] 1.43-12.9, p = 0.0095) was the sole independent predictive factor for POPF. For patients with a soft pancreas, VFA/SMI ≥ 1.94 (OR 5.67, 95% CI 2.05-15.7, p = 0.0008) was again the sole independent predictive factor for POPF.

CONCLUSION

Preoperative CT images can examine pancreatic fatty infiltration, and patients who had POPF were significantly associated with a high RPF. Among several parameters, VFA/SMI was the only independent predictive factor for clinically relevant POPF. Preoperative evaluation of these body composition variables and the pancreatic configuration could be useful for predicting POPF.

Power of computed-tomography-defined sarcopenia for prediction of morbidity after pancreaticoduodenectomy

Background

The goal of our study was to evaluate the current approach in prediction of postoperative major complications after pancreaticoduodenectomy (PD), especially symptomatic pancreatic fistula (POPF), using parameters derived from computed tomography (CT).

Methods

Patients after PD were prospectively collected in a database of the local department of surgery and all patients with CT scans available were assessed in this study. CT parameters were measured at the level of the intervertebral disc L3/L4 and consisted of the areas of the visceral adipose tissue (A_VAT), the diameters of the pancreatic parenchyma (DPP) and the pancreatic duct (DPD), the areas of ventral abdominal wall muscle (A_MVEN), psoas muscle (A_MPSO), paraspinal muscle (A_MSPI), total muscle (A_MTOT), as well as the mean muscle attenuation (MA) and skeletal muscle index (SMI). Mann-Whitney-U Test for two independent samples and binary logistic regression were used for statistical analysis.

Results

One hundred thirty-nine patients (55 females, 84 males) were included. DPD was 2.9 mm (Range 0.7–10.7) on median and more narrow in patients with complications equal to or greater stadium IIIb (p < 0.04) and severe POPF (p < 0.01). DPP median value was 17 (6.9–37.9) mm and there was no significant difference regarding major complications or POPF. A_VAT showed a median value of 127.5 (14.5–473.0) cm² and was significantly larger in patients with POPF (p < 0.01), but not in cases of major complications (p < 0.06). A_MPSO, A_MSPI, A_MVEN and A_MTOT showed no significant differences between major complications and POPF. MA was both lower in groups with major complications (p < 0.01) and POPF (p < 0.01). SMI failed to differentiate between patients with or without major complications or POPF.

Conclusion

Besides the known factors visceral obesity and narrowness of the pancreatic duct, the mean muscle attenuation can easily be examined on routine preoperative CT scans and seems to be promising parameter to predict postoperative complications and POPF.

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.

Excess intraoperative fluid volume administration is associated with pancreatic fistula after pancreaticoduodenectomy: A retrospective multicenter study

Recent studies on perioperative fluid administration in patients undergoing pancreaticoduodenectomy (PD) have suggested that increased fluid loads are associated with worse perioperative outcomes. The purpose of this study was to investigate the relationship between intraoperative fluid (IOF) administration and postoperative pancreatic fistula (POPF), and to determine additional risk factors affecting pancreatic fistula in patients undergoing PD.From 2005 to 2014, a total of 182 patients with various periampullary diseases after PD were reviewed retrospectively at Dongguk University Ilsan Hospital, Chung-Ang University Hospital, and Dongnam Institute of Radiological and Medical Sciences. Patients were assigned to high or low IOF groups based on more or less fluid administration for supplementation of estimated blood loss and maintenance volume (12.5 mL/kg/h) than planned, respectively. The associations between IOF administration, pancreatic fistula development, and perioperative outcomes were evaluated.A total of 98 patients were assigned to the high-IOF group, and 84 to the low-IOF group. Risk factors for pancreatic fistula after univariate analysis were assignment to the high-IOF group, higher preoperative serum hemoglobin level, ampullary or bile duct cancer, pylorus preserving PD, small pancreatic duct, duct-to-mucosa pancreatojejunostomy, use of a stent, and mesh application to pancreatojejunal anastomosis. Among these, assignment to the high-IOF group (hazard ratio [HR] = 5.501, 95% CI 1.624-18.632, P = .006) and a small (<4 mm) pancreatic duct (HR = 4.129, 95% CI 1.569-14.658, P = .035) were identified as independent risk factors for the development of pancreatic fistula after multivariate analysis. However, long-term survival rate did not differ according to IOF group or duct size.Excessive IOF volume administration is associated with an increased incidence of pancreatic fistula after pancreaticoduodenectomy.