Preoperative fecal elastase-1 (FE-1) adds value in predicting post-operative pancreatic fistula: not all soft pancreas share the same risk - A prospective analysis on 105 patients

Proposal of the novel predictive model for postoperative pancreatic fistula in distal pancreatectomy for pancreatic tumor based on preoperative imaging parameters and stapler handling

BACKGROUND

Distal pancreatectomy (DP) using linear staplers is widely performed; however, postoperative pancreatic fistulas (POPF) remain an issue. This study aimed to analyze preoperative risk factors for POPF and assess stapler handling.

METHODS

We retrospectively analyzed consecutive patients who underwent DP for pancreatic tumors using a linear stapler between 2014 and 2022. Preoperative measurements included pancreas-to-muscle signal intensity ratio (SIR) on fat-suppressed T1-weighted magnetic resonance imaging (MRI). The main outcome was clinically relevant POPF of the 2016 International Study Group of Pancreatic Fistulas definition. The predictive ability of the model was compared with the distal fistula risk score (D-FRS) by using the area under the receiver operating characteristic curve (AUROC).

RESULTS

Among the 81 patients, POPF occurred in 31 (38.2%). Multivariate analysis identified computed tomography-measured pancreatic thickness (odds ratio [OR] 1.30, 95% confidence interval [CI] 1.05-1.61, p = 0.009) and SIR on T1-weighted MRI (OR 6.85, 95% CI 1.71-27.4, p = 0.002) as preoperative predictors. A novel preoperative model, "Thickness × MRI (TM)"-index, was established by multiplying these two variables. The TM-index exhibited the highest predictability preoperatively (AUROC 0.757, 95% CI 0.649-0.867). In the intraoperative variable analyses, TM-index (p < 0.001), thin cartridge application (p = 0.032), and short pre-firing compression (p = 0.047) were identified as significant risk factors for POPF. The model's AUROC combined with these two stapler handling methods was higher than D-FRS (0.851 vs. 0.660, p = 0.006).

CONCLUSIONS

The novel preoperative model exhibited excellent predictability. Thick cartridge use and long pre-firing compression were protective factors against POPF. This model may facilitate preventive surgical strategy development to reduce POPF.

Quantitative Edge Analysis of Pancreatic Margins in Patients with Chronic Pancreatitis: A Correlation with Exocrine Function

BACKGROUND

Many efforts have been made to improve accuracy and sensitivity in diagnosing chronic pancreatitis (CP), obtaining quantitative assessments related to functional data. Our purpose was to correlate a computer-assisted analysis of pancreatic morphology, focusing on glandular margins, with exocrine function-measured by fecal elastase values-in chronic pancreatitis patients.

METHODS

We retrospectively reviewed chronic pancreatitis patients who underwent fecal elastase assessment and abdominal MRI in our institute within 1 year. We identified 123 patients divided into three groups based on the fecal elastase value: group A with fecal elastase > 200 μg/g; group B with fecal elastase between 100 and 200 μg/g; and group C with fecal elastase < 100 μg/g. Computer-assisted quantitative edge analysis of pancreatic margins was made on non-contrast-enhanced water-only Dixon T1-weighted images, obtaining the pancreatic margin score (PMS). PMS values were compared across groups using a Kruskal-Wallis test and the correlation between PMS and fecal elastase values was tested with the Spearman's test.

RESULTS

A significant difference in PMS was observed between the three groups (p < 0.0001), with a significant correlation between PMS and elastase values (r = 0.6080).

CONCLUSIONS

Quantitative edge analysis may stratify chronic pancreatitis patients according to the degree of exocrine insufficiency, potentially contributing to the morphological and functional staging of this pathology.

Current Perioperative Care in Pancreatoduodenectomy: A Step-by-Step Surgical Roadmap from First Visit to Discharge

Pancreaticoduodenectomy (PD) is a mainstay in the management of periampullary tumors. Treatment algorithms increasingly employ a multimodal strategy, which includes neoadjuvant and adjuvant therapies. However, the successful treatment of a patient is contingent on the execution of a complex operation, whereby minimizing postoperative complications and optimizing a fast and complete recovery are crucial to the overall success. In this setting, risk reduction and benchmarking the quality of care are essential frameworks through which modern perioperative PD care must be delivered. The postoperative course is primarily influenced by pancreatic fistulas, but other patient- and hospital-associated factors, such as frailty and the ability to rescue from complications, also affect the outcomes. A comprehensive understanding of the factors influencing surgical outcomes allows the clinician to risk stratify the patient, thereby facilitating a frank discussion of the morbidity and mortality of PD. Further, such an understanding allows the clinician to practice based on the most up-to-date evidence. This review intends to provide clinicians with a roadmap to the perioperative PD pathway. We review key considerations in the pre-, intra-, and post-operative periods.

The net parenchymal thickness predicts pancreatic fistula after pancreaticoduodenectomy: a retrospective cohort study of objective data

BACKGROUND

The clinically relevant postoperative pancreatic fistula (CR-POPF) is still a challenging complication of pancreaticoduodenectomy (PD). This study aims to explore the predictors of CR-POPF after PD, including net parenchymal thickness (NPT) of pancreatic neck.

METHODS

The consecutive patients who underwent PD at a tertiary hospital were retrospectively reviewed. Univariate and multivariate analyses were conducted on the perioperative data, which was mainly extracted from the objective data, containing the results from the laboratory tests and the imaging examination. NPT refers to the total thickness of pancreatic gland excluding main pancreatic duct (MPD) at the CT film.

RESULTS

Univariate analyses showed that total serum bilirubin (TBiL) and albumin (ALB) levels, MPD size and NPT were significantly different between the patients with and without CR-POPF. The white blood cell count, the rate of intra-abdominal infection (IAI) and the postoperative length of hospital stay (LOS) were associated with the incidence of CR-POPF. The proportion of patients with pancreatic adenocarcinoma or chronic pancreatitis was significantly lower in the CR-POPF group than in the non-CR-POPF group. Multivariate analyses manifested that ALB ≤35 g/L and NPT >10 mm were two of the independent risk factors for CR-POPF.

CONCLUSION

Preoperative ALB ≤35 g/L and NPT > 10 mm were both the independent predictors of CR-POPF. CR-POPF was associated with the higher IAI rate and the extended LOS.

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.

Establishing the blood reference interval of pancreatic elastase-1: A prospective study

BACKGROUND AND AIM

Pancreatic elastase-1 (PE-1) has been investigated in pancreatic disorders. However, the reference interval (RI) of PE-1 in blood remains unconfirmed. We aimed to establish the blood RI of PE-1 in an adult population.

METHODS

In this prospective cross-sectional study, we enrolled 400 adults who had received the whole-body physical check-up program between May 1, 2019 and November 20, 2019. The serum and plasma PE-1 levels were measured by latex turbidimetric immunoassay in different storage conditions (fresh, refrigerated, and frozen). The 95% and 99% RI of PE-1 were calculated according to the Clinical & Laboratory Standards Institute guidelines. The correlations between PE-1 and other parameters were analyzed using multivariable regression models. Ultimately, 38 patients with acute pancreatitis were prospectively recruited as the validation cohort.

RESULTS

The PE-1 levels in fresh serum were highly correlated with those in refrigerated (R²  = 0.998) or frozen (R²  = 0.942) samples; however, plasma should not be suggested in frozen conditions (plasma vs serum: R²  = 0.185). In the RI study population (202 male & 198 female participants), the median age was 52.6 (25-75% interquartile range: 43.1-61.0). The 95% and 99% RIs of PE-1 were 30.0-221.0 and 22.0-359.0 ng/dL, respectively. Triglycerides (β = 0.106, P = 0.033), lipase (β = 0.154, P = 0.007), and CA19-9 (β = 0.130, P = 0.008) were independent factors associated with PE-1. In the pancreatitis validation cohort, with a cut-off value of 359.0 ng/dL, the sensitivity and specificity were 100% and 99.8%, respectively.

CONCLUSION

The RI of PE-1 established in this study can be used for further applications. Serum is the suggested form for frozen sample storage.

Beyond liquid biopsy: Toward non-invasive assays for distanced cancer diagnostics in pandemics

Liquid biopsy technologies have seen a significant improvement in the last decade, offering the possibility of reliable analysis and diagnosis from several biological fluids. The use of these technologies can overcome the limits of standard clinical methods, related to invasiveness and poor patient compliance. Along with this there are now mature examples of lab-on-chips (LOC) which are available and could be an emerging and breakthrough technology for the present and near-future clinical demands that provide sample treatment, reagent addition and analysis in a sample-in/answer-out approach. The possibility of combining non-invasive liquid biopsy and LOC technologies could greatly assist in the current need for minimizing exposure and transmission risks. The recent and ongoing pandemic outbreak of SARS-CoV-2, indeed, has heavily influenced all aspects of life worldwide. Ordinary tasks have been forced to switch from “in presence” to “distanced”, limiting the possibilities for a large number of activities in all fields of life outside of the home. Unfortunately, one of the settings in which physical distancing has assumed noteworthy consequences is the screening, diagnosis and follow-up of diseases.

In this review, we analyse biological fluids that are easily collected without the intervention of specialized personnel and the possibility that they may be used -or not-for innovative diagnostic assays. We consider their advantages and limitations, mainly due to stability and storage and their integration into Point-of-Care diagnostics, demonstrating that technologies in some cases are mature enough to meet current clinical needs.

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.

Higher cumulative fluid follows a pancreaticoduodenectomy as a single modifiable factor for post-operative pancreatic fistula: Risk factor analysis

BACKGROUND

Postoperative pancreatic fistula (POPF) is one of the major complications after pancreaticoduodenectomy. There have been many studies into the risk factors determining POPF. Some studies have reported a higher peri-operative fluid balance associated with POPF, however, the pertinent findings remain controversial. The aims of this study were to determine risk factors of clinically relevant-post operative pancreatic fistula (CR-POPF) after pancreaticoduodenectomy and an association between peri-operative fluid balance and the incidence of CR-POPF.

MATERIALS AND METHODS

This is a retrospective cohort study included all adult patients who underwent an elective open pancreaticoduodenectomy in our center from 2005 to 2018. Patients who did not have POPF related data were excluded from study. We divided patients into CR-POPF and no CR-POPF group. Peri-operative data including amount and type of fluid were compared between two groups. Logistic regression analysis was used to identify the independent risk factors of CR-POPF.

RESULTS

There were 223 pancreaticoduodenectomies done in our center during that period. The incidence of CR-POPF was 15.2 %. Patients in CR-POPF group had significant higher BMI, higher serum globulin level, smaller pancreatic duct diameter and higher cumulative fluid balance per body weight (FBPBW) at post-operative day 3. Multivariable analysis showed BMI >23 kg/m², diagnosis other than pancreatic duct adenocarcinoma or chronic pancreatitis and higher cumulative FBPBW at post-operative day 3 were the independent risk factors for CR-POPF.

CONCLUSIONS

Post-operative fluid balance was the post-operative modifiable risk factor to reduce CR-POPF. Higher positive post-operative fluid balance should be avoided especially in higher CR-POPF risk patients.

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.

Pros and pitfalls of externalized trans-anastomotic stent as a mitigation strategy of POPF: a prospective risk-stratified observational series

BACKGROUND

Several advantages and pitfalls have been related to externalized trans-anastomotic stents (ETS) after pancreaticoduodenectomy. The purpose of this study was to investigate the effect of an ETS effect in a risk-stratified setting.

METHODS

Data from patients at either intermediate- or high-risk for postoperative pancreatic fistula (POPF) following pancreaticoduodenectomy were prospectively analyzed from January 2016 to December 2019. Outcomes included POPF rate, mean complication burden (ACB), and complications related to ETS malfunction.

RESULTS

A total of 540 patients met the inclusion criteria. Following an intention-to-treat analysis, there was no difference in terms of POPF and the ACB in the intermediate (22 vs.29%, p = 0.148; 0.38 vs.0.24, p = 0.082) and high-risk categories (58 vs.37%, p = 0.103; 0.33 vs.0.33, p = 0.478) comparing PJ to PJ-ETS. Excluding patients experiencing ETS malfunction (n = 45, 22%), ETS was associated with a significantly reduced ACB in the intermediate-risk (0.38 vs.0.26, p = 0.009) and POPF rate in the high-risk category (58 vs.32%, p = 0.033). In patients with ETS malfunction an increased rate of severe morbidity (Clavien-Dindo ≥ III, 33 vs.19%, p = 0.044) was observed as compared to patients with functioning ETS.

CONCLUSION

ETS provides crucial advantages for prevention and mitigation of POPF depending on risk setting and its correct functioning. ETS malfunction is not uncommon and increases morbidity. Improving ETS design and fixing technique might lead to better outcomes.