Prediction of pancreatic fistula after pancreatoduodenectomy by preoperative dynamic CT and fecal elastase-1 levels

Radiological parameters to predict pancreatic texture: Current evidence and future perspectives

Preoperative prediction of the postoperative pancreatic fistula risk is critical in the current era of minimally invasive pancreatic surgeries to tailor perioperative management, thereby minimizing postoperative morbidity. Pancreatic duct diameter can be readily measured by any routine imaging used to diagnose pancreatic disease. However, radiological evaluation of pancreatic texture, an important determinant of pancreatic fistula, has not been widely used to predict the risk of postoperative pancreatic fistula. Qualitative and quantitative assessment of pancreatic fibrosis and fat fraction provides the basis for predicting pancreatic texture. Traditionally computed tomography has been utilized in identifying and characterizing pancreatic lesions and background parenchymal pathologies. With the increasing utilisation of endoscopic ultrasound and magnetic resonance imaging for evaluating pancreatic pathologies, elastography is emerging as a promising tool for predicting pancreatic texture. Also, recent studies have shown that early surgery for chronic pancreatitis is associated with better pain relief and preservation of pancreatic function. Pancreatic texture assessment can allow early diagnosis of chronic pancreatitis, facilitating early intervention. The present review outlines the current evidence in utilizing various imaging modalities for determining the pancreatic texture based on different parameters and image sequences. However, multidisciplinary investigations using strong radiologic-pathologic correlation are needed to standardize and establish the role of these non-invasive diagnostic tools in predicting pancreatic texture.

Do preoperative pancreatic computed tomography attenuation index and enhancement ratio predict pancreatic fistula after pancreaticoduodenectomy?

BACKGROUND

The commonly used predictors of clinically relevant postoperative pancreatic fistula (CR-POPF) following pancreaticoduodenectomy (PD) have subjective assessment components and can be used only in the postoperative setting. Also, the available objective predictors based on preoperative cross-sectional imaging were not prospectively studied.

AIM

To evaluate the accuracy of the pancreatic attenuation index (PAI) and pancreatic enhancement ratio (PER) for predicting CR-POPF following PD and its correlation with pancreatic fat fraction and fibrosis.

METHODS

A prospective observational study included patients who underwent PD for benign and malignant pathology of the periampullary region or pancreatic head between February 2019 and February 2021. Patients undergoing extended or total pancreatectomy and those with severe atrophy of pancreatic tissue or extensive parenchymal calcifications in the pancreatic head and neck precluding calculation of PAI and PER were excluded from the study. Preoperatively PAI was measured in the neck of the pancreas by marking regions of interest (ROI) in the non-contrast computed tomography (CT), and PER was measured during the contrast phase of the CT abdomen. Also, the fibrosis score and fat fraction of the pancreatic neck were assessed during the histopathological examination. Demographic, clinical and preoperative radiological indices (PAI, PER) were evaluated to predict CR-POPF. Preoperative pancreatic neck CT indices were correlated with the histopathological assessment of fat fraction and fibrosis.

RESULTS

Of the 70 patients who underwent PD, 61 patients fulfilling the inclusion criteria were included in the analysis. The incidence of CR-POPF was 29.5% (18/61). PAI had no association with the development of CR-POPF. Of the preoperative parameters, PER (mean ± standard deviation [SD]) was significantly lower in patients developing CR-POPF (0.58 ± 0.20 vs 0.81 ± 0.44, P = 0.006). The area under the curve for the PER was 0.661 (95%CI: 0.517-0.804), which was significant (P = 0.049). PER cut-off of 0.673 predicts CR-POPF with 77.8% sensitivity and 55.8% specificity. PAI and PER had a weak negative correlation (Strength-0.26, P = 0.037). Also, PER showed a moderately positive correlation with fibrosis (Strength 0.50, P < 0.001). Patients with CR-POPF had a significantly higher incidence of the intraabdominal abscess (50% vs 2.3%, P < 0.001), delayed gastric emptying (83.3% vs 30.2, P < 0.001), and prolonged mean (± SD) postoperative hospital stay (26.8 ± 13.9 vs 9.6 ± 3.6, P = 0.001).

CONCLUSION

PER exhibited good accuracy in predicting the development of CR-POPF. PER additionally showed a good correlation with PAI and fibrosis scores and may be used as an objective preoperative surrogate for assessing pancreatic texture. However, ROI-based PAI did not show any association with CR-POPF and pancreatic fat fraction.

The usefulness of preoperative exocrine function evaluated by the 13C-trioctanoin breath test as a significant physiological predictor of pancreatic fistula after pancreaticoduodenectomy

Background

The association between pancreatic fistula (PF) after pancreaticoduodenectomy (PD) and preoperative exocrine function is yet to be elucidated. This study aimed to evaluate the association between the preoperative results of the ¹³C-trioctanoin breath test and the occurrence of PF, showing the clinical relevance of the breath test in predicting PF.

Method

A total of 80 patients who underwent ¹³C-trioctanoin breath tests prior to PD from 2006 to 2018 were included in this study. Univariate and multivariate analyses were conducted to reveal the preoperative predictors of PF, showing the association between ¹³C-trioctanoin absorption and PF incidence.

Results

Among 80 patients (age, 68.0 ± 11.9 years, 46 males and 34 females; 30 pancreatic ductal adenocarcinoma [PDAC]/50 non-PDAC patients), the incidence of PF was 12.5% (10/80). Logistic regression analysis results revealed that the frequency of PF increased significantly as the ¹³C-trioctanoin breath test value (Aa% dose/h) increased (odd’s ratio: 1.082, 95% confidence interval: 1.007–1.162, p = 0.032). Moreover, the optimal cutoff value of the preoperative fat absorption level to predict PF was 38.0 (sensitivity, 90%; specificity, 74%; area under the curve, 0.78; p = 0.005). Indeed, the incidence of PF was extremely higher in patients whose breath test value was greater than 38.0 (33%, 9/27) compared with that in patients with values less than 38.0 (1.8%, 1/53).

Conclusions

Favorable preoperative fat absorption evaluated using the ¹³C-trioctanoin breath test is a feasible and objective predictor of PF after PD.

A preserved pancreatic exocrine function after pancreatectomy may be a crucial cause of pancreatic fistula: paradoxical results of the 13C-trioctanoin breath test in the perioperative period

PURPOSE

The aim of this study was to elucidate the association between pancreatic fistula (PF) and the sequential changes in the perioperative exocrine function after pancreatectomy.

METHODS

The subjects were 96 patients who underwent a ¹³C-trioctanoin breath test before and 1 month after pancreatectomy, between 2006 and 2018. We retrospectively compared the pre- and postoperative fat absorption levels between patients with PF (PF group; n = 17) and without PF (non-PF group; n = 79) using the breath test.

RESULTS

The preoperative level of ¹³C-trioctanoin absorption (%dose/h) was comparable between the non-PF and PF groups (36.5 vs. 36.9). In the non-PF group, ¹³C-trioctanoin absorption was significantly decreased after surgery in comparison to the preoperative setting (post-operative 28.5; pre-operative 36.5; p < 0.0001), whereas these values were comparable (post-operative 36.9; pre-operative 34.5; p = 0.129) in the PF group. Moreover, postoperative absorption in the PF group was significantly better than that in the non-PF group (34.5 vs. 28.5%, p = 0.0003). The maximum drain amylase level was significantly higher in patients with a ¹³C-trioctanoin absorption level (%dose/h) of ≥ 30 in comparison to patients with levels of < 30 (2502 vs. 398 U/L, p = 0.001).

CONCLUSION

PF did not exacerbate the pancreatic exocrine function in the early postoperative period, and the acceleration or preservation of the exocrine function after surgery may be an important cause of PF.

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.

[Contrast-enhanced computed tomography in evaluation of pancreatic stump volume in pancreaticoduodenectomy]

OBJECTIVE

To analyze the role of contrast-enhanced computed tomography in evaluation of pancreatic stump volume for prediction of significant pancreatic fistula.

MATERIAL AND METHODS

A retrospective analysis enrolled 99 patients. Patients were divided into 2 groups depending on the course of postoperative period and development of clinically significant pancreatic fistula. The first group included 24 patients (25%) with clinically significant postoperative pancreatic fistula. The second group included 75 patients (75%) without postoperative complications. Pancreatic structure, pancreatic parenchyma thickness (mm), pancreatic duct diameter (mm) and volume of pancreatic stump (cm³) were preoperatively analyzed considering contrast-enhanced computed tomography data.

RESULTS

The risk of postoperative pancreatic fistula is 10 times higher in case of soft structure of the pancreas, 1,7 times higher in decrease of pancreatic duct diameter, 9,3 times higher in increased volume of residual pancreatic parenchyma, 8.6 times higher in increase of pancreatic parenchyma thickness.

CONCLUSION

Contrast-enhanced computed tomography is valuable for preoperative evaluation of the volume of residual pancreatic parenchyma and identification of patients with high risk of postoperative pancreatic fistula.

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.

Preoperative CT texture features predict prognosis after curative resection in pancreatic cancer

Pancreatic cancer is a lethal disease, and resistance to chemotherapy is a critical factor influencing the postoperative prognosis. Tumour heterogeneity is an important indicator of chemoresistance. Therefore, we analysed tumour heterogeneity in preoperative computed tomography scans by performing texture analysis using the grey-level run-length matrix and analysed the correlation of survival with the value obtained in these analyses. We analysed 116 consecutive patients who underwent curative resection and had preoperative contrast-enhanced computed tomography data available for analysis. A region of interest was drawn on all slices with a visible tumour and normal pancreas on the arterial phase computed tomography scans; the correlation of pathological characteristics with grey-level run-length matrix features was analysed. We then performed Kaplan–Meier survival curve analysis among pancreatic cancer patients. The grey-level non-uniformity values in grey-level run-length matrix features for tumours were higher than those for normal pancreas. High grey-level non-uniformity values represent a non-uniform texture, i.e., heterogeneity. Grey-level run-length matrix features showed that recurrence-free survival was shorter in the group with high grey-level non-uniformity 135 values (p = 0.025). Our analyses of the correlation between pathological outcomes and grey-level run-length matrix features in pancreatic cancer patients showed that grey-level non-uniformity values were powerful prognostic indicators.

Efficacy of Triple-Drug Therapy to Prevent Pancreatic Fistulas in Patients With High Drain Amylase Levels After Pancreaticoduodenectomy

BACKGROUNDS

Prior studies have suggested that drain amylase level is a predictive marker for developing pancreatic fistulas (PFs) after pancreaticoduodenectomy (PD). However, means of preventing PF after discovering high drain amylase levels have not been previously established. The purpose of this study was to evaluate the efficacy of a combination drug therapy (using three drugs; gabexate mesilate, octreotide, and carbapenem antibiotics, named as triple-drug therapy [TDT]) regimen in preventing PF for patients with high drain amylase levels on postoperative day (POD) 1 after PD.

MATERIALS AND METHODS

We divided the 183 patients who underwent PD into two groups in accordance with their enrollment in the study: for those enrolled early in the study (early period), TDT was not administered to patients with high drain amylase level; however, for those enrolled later in the study (late period), TDT was administered if drain amylase levels were over 10,000 IU/L on POD 1. We retrospectively compared the incidence of PF between the two groups.

RESULTS

Incidences of PFs were statistically, significantly prevented in the late group (early 17% versus late 6%; P = 0.01). For patients with low levels of drain amylase (<10,000 IU/L), the PF ratio was equivalent between two groups (early 8% versus late 5%; P = 0.56); however, PFs in patients with high drain amylase levels in the late period group were dramatically prevented by TDT administration (early 89% versus late 11%; P < 0.001).

CONCLUSIONS

TDT may be a promising therapy to prevent PFs in patients with high drain amylase levels after PD.

Postoperative pancreatic fistula: a review of traditional and emerging concepts

Postoperative pancreatic fistula (POPF) remains the major cause of morbidity after pancreatic resection, affecting up to 41% of cases. With the recent development of a consensus definition of POPF, there has been a large number of reports examining various risk factors, prediction models, and mitigation strategies for this costly complication. Despite these strategies, the rates of POPF have not significantly diminished. Here, we review the literature and evidence regarding both traditional and emerging concepts in POPF prediction, prevention, and management. In particular, we review the evidence for the association between postoperative pancreatitis and POPF, and present a novel proposed mechanism for the development of POPF.