A pleiotropy scan to discover new susceptibility loci for pancreatic ductal adenocarcinoma

Pleiotropic variants (i.e., genetic polymorphisms influencing more than one phenotype) are often associated with cancer risk. A scan of pleiotropic variants was successfully conducted ten years ago in relation to pancreatic ductal adenocarcinoma susceptibility. However, in the last decade, genetic association studies performed on several human traits have greatly increased the number of known pleiotropic variants. Based on the hypothesis that variants already associated with a least one trait have a higher probability of association with other traits, 61,052 variants reported to be associated by at least one genome wide association study (GWAS) with at least one human trait were tested in the present study consisting of two phases (discovery and validation), comprising a total of 16,055 pancreatic ductal adenocarcinoma (PDAC) cases and 212,149 controls. The meta-analysis of the two phases showed two loci (10q21.1-rs4948550 (P=6.52×10-5) and 7q36.3-rs288762 (P=3.03×10-5) potentially associated with PDAC risk. 10q21.1-rs4948550 shows a high degree of pleiotropy and it is also associated with colorectal cancer risk while 7q36.3-rs288762 is situated 28,558 base pairs upstream of the Sonic Hedgehog (SHH) gene, which is involved in the cell differentiation process and PDAC etiopathogenesis. In conclusion, none of the single nucleotide polymorphisms (SNPs) showed a formally statistically significant association after correction for multiple testing. However, given their pleiotropic nature and association with various human traits including colorectal cancer, the two SNPs showing the best associations with PDAC risk merit further investigation through fine mapping and ad hoc functional studies.

Decreased mebrofenin uptake in patients with non-colorectal liver tumors requiring liver volume augmentation-a single-center analysis

BACKGROUND

Posthepatectomy liver failure (PHLF) remains a life-threatening complication after hepatectomy. To reduce PHLF, a preoperative assessment of liver function is indispensable. For this purpose, 99mTc-mebrofenin hepatobiliary scintigraphy with SPECT (MSPECT) can be used. The aim of the current study was to evaluate the predictive value of MSPECT for PHLF in patients with non-colorectal liver tumors (NCRLT) compared to patients with colorectal liver metastasis (CRLM) undergoing extended liver resection.

METHODS

We included all patients undergoing extended liver resections via two-stage procedures between January 2019 and December 2021 at the University Medical Center Hamburg-Eppendorf, Germany. All patients received a preoperative MSPECT.

RESULTS

Twenty patients were included. In every fourth patient, PHLF was observed. Four patients had PHLF grade C. There were no differences between patients with CRLM and NCRLT regarding PHLF rate and future liver remnant (FLR) volume. Patients with CRLM had higher mebrofenin uptake in the FLR compared to those with NCRLT (2.49%/min/m2 vs. 1.51%/min/m2; p = 0.004).

CONCLUSION

Mebrofenin uptake in patients with NCRLT was lower compared to those patients with CRLM. However, there was no difference in the PHLF rate and FLR volume. Cut-off values for the mebrofenin uptake might need adjustments for different surgical indications, surgical procedures, and underlying diseases.

Robotic distal pancreatectomy, a novel standard of care? First benchmark values for surgical outcomes from 14 international expert centers

Objective

Robotic distal pancreatectomy (DP) is emerging as the preferred treatment for body and tail tumors of the pancreas. To enable conclusive comparisons with the standard open or laparoscopic approaches and robotic surgery among centers, novel benchmark outcome values are urgently needed. Therefore, the aim of this study was to identify benchmark values from expert centers beyond the learning curve.

Methods

This multicenter study analyzed outcomes from consecutive patients undergoing robotic DP for resectable malignant or benign lesions from 14 international expert centers. After the learning curve, defined as the first 10 cases of robotic DP, all consecutive patients were included from the start of the program up to June 2020 with a minimum follow-up of 1 year. Benchmark patients were those without significant comorbidities including obesity (BMI >35 kg/m2) cardiac disease, chronic pulmonary disease.

Benchmark cutoff values were derived from the 75th or the 25th percentile of the median values of all benchmark centers.

Results

After reaching the learning curve, 289 (47%) of a total of 614 consecutive patients qualified as benchmark cases. The proportion of benchmark patients varied between 24%-64% per center. Benchmark cut-offs showed a low 6 month- postoperative mortality (<0.6%), but high overall morbidity (<58.3%). Benchmark cutoffs for operative time (<300 min), conversion rate (<3%), clinically relevant pancreatic fistulas (<26.9%), CCI at 90-days (<14.8), hospital stay (<7 days) and readmission rate (<22.9%). Benchmark cut-offs for complications remained unchanged after 3 months follow-up. For ductal adenocarcinoma benchmark cutoffs for number of lymph nodes were > 19 with an R0 resection rate of > 85%, and an overall survival of >86% and >52% after 1- and 5-years, respectively. Centers with a low cohort of benchmark patients (more difficult cases) had less clinically relevant pancreatic fistula (9% vs. 23%) and less overall complications (32% vs. 48%).

Conclusion

This benchmark analysis sets novel reference values for robotic DP, indicating favorable outcomes as compared to laparoscopic and open DP. These references values may serve for quality control of surgery in centers embarking in robotic DP, and include the procedure in the standard of care.

[Importance of surgery in distant metastatic pancreatic neuroendocrine neoplasms]

The majority of patients with pancreatic neuroendocrine neoplasms (pNEN) already present with distant metastases at diagnosis. The heterogeneity of pNEN and the broad spectrum of treatment options make adequate patient selection and an evidence-based strategy essential. In metastatic pNEN both primary resection and resection of liver metastases have been shown to improve overall survival. Surgical treatment of liver metastases can also be carried out with palliative intent, especially for symptomatic pNEN and can have a positive effect on disease-free survival and overall survival. Classical hepatectomy techniques and innovative techniques (two-stage resections, liver transplantation) are available to the surgeon. In complex growth types of liver metastases, there is increasing evidence for a combination of surgery and ablative methods. Due to a relevant risk of recurrence following liver resection, pNEN patients need to be included in multimodal treatment concepts. Current areas of interest in the treatment of metastatic pNEN are the use of adjuvant/neoadjuvant chemotherapy and surgery in G3-NEN and G3-NEC patients. The aim of this review is to give an overview on the impact of surgery in the situation of distant metastatic NEN of the pancreas.

Learning Curves in Open, Laparoscopic, and Robotic Pancreatic Surgery: A Systematic Review and Proposal of a Standardization

Objective

To depict and analyze learning curves for open, laparoscopic, and robotic pancreatoduodenectomy (PD) and distal pancreatectomy (DP).

Background

Formal training is recommended for safe introduction of pancreatic surgery but definitions of learning curves vary and have not been standardized.

Methods

A systematic search on PubMed, Web of Science, and CENTRAL databases identified studies on learning curves in pancreatic surgery. Primary outcome was the number needed to reach the learning curve as defined by the included studies. Secondary outcomes included endpoints defining learning curves, methods of analysis (statistical/arbitrary), and classification of learning phases.

Results

Out of 1115 articles, 66 studies with 14,206 patients were included. Thirty-five studies (53%) based the learning curve analysis on statistical calculations. Most often used parameters to define learning curves were operative time (n = 51), blood loss (n = 17), and complications (n = 10). The number of procedures to surpass a first phase of learning curve was 30 (20-50) for open PD, 39 (11-60) for laparoscopic PD, 25 (8-100) for robotic PD (P = 0.521), 16 (3-17) for laparoscopic DP, and 15 (5-37) for robotic DP (P = 0.914). In a three-phase model, intraoperative parameters improved earlier (first to second phase: operating time -15%, blood loss -29%) whereas postoperative parameters improved later (second to third phase: complications -46%, postoperative pancreatic fistula -48%). Studies with higher sample sizes showed higher numbers of procedures needed to overcome the learning curve (rho = 0.64, P < 0.001).

Conclusions

This study summarizes learning curves for open-, laparoscopic-, and robotic pancreatic surgery with different definitions, analysis methods, and confounding factors. A standardized reporting of learning curves and definition of phases (competency, proficiency, mastery) is desirable and proposed.

Applying an intraoperative predictive indicator for postoperative pancreatic fistula: randomized preclinical trial

Leaking pancreatic fluid can contribute to postoperative pancreatic fistula (POPF), which can complicate pancreatic surgery. Surgeons lack reliable tools to identify pancreatic leaks, so a novel hydrogel indicator called SmartPAN was developed for intraoperative application. In this preclinical efficacy assessment study, SmartPAN was capable of detecting sites associated with biochemical leak and POPF-related symptoms, thereby guiding effective closure. Thus, SmartPAN may help to reduce POPF development in upcoming clinical trials.

Prospective trial to evaluate the prognostic value of different nutritional assessment scores for survival in pancreatic cancer surgery

Objective

Malnutrition is associated with poor survival in pancreatic cancer patients. Nutritional scores show great heterogeneity diagnosing malnutrition. The aim of this study was to find the score best suitable to identify patients with malnutrition related to worse survival after surgery for PDAC.

Methods

Risk of malnutrition was evaluated preoperatively using twelve nutritional assessment scores. Patients were followed-up prospectively for at least 3 years. Patients at risk for malnutrition were compared to those not at risk according to each score using Kaplan Meier survival statistics.

Results

A total of 116 Patients receiving a PDAC resection in curative intent were included. Malnutrition according to the Subjective Global Assessment score (SGA), the Short Nutritional Assessment Questionnaire (SNAQ) and the INSYST2 score was associated with worse overall survival (SGA: at-risk: 392 days; not at-risk: 942 days; p = 0.001; SNAQ: at-risk: 508 days; not at-risk: 971 days; p = 0.027; INSYST2: at-risk: 538 days; not at risk: 1068; p = 0.049). In the multivariate analysis SGA (HR of death 2.22, 95% CI 1.37-3.6, p = 0.002) was associated with worse overall survival.

Conclusion

Malnutrition as defined by the Subjective Global Assessment is independently associated with worse survival in resected PDAC patients. The SGA should be used to stratify PDAC patients in clinical studies. If severely malnourished patients according to the SGA profit from intensified nutritional therapy should be evaluated in a randomized controlled trial.

Technical advances in surgery for pancreatic cancer

BACKGROUND

Multimodal treatment concepts enhance options for surgery in locally advanced pancreatic ductal adenocarcinoma (PDAC). This review provides an overview of technical advances to facilitate curative-intent resection in PDAC.

METHODS

A review of the literature addressing current technical advances in surgery for PDAC was performed, and current state-of-the-art surgical techniques summarized.

RESULTS

Artery-first and uncinate-first approaches, dissection of the anatomical triangle between the coeliac and superior mesenteric arteries and the portomesenteric vein, and radical antegrade modular pancreatosplenectomy were introduced to enhance the completeness of resection and reduce the risk of local recurrence. Elaborated techniques for resection and reconstruction of the mesenteric-portal vein axis and a venous bypass graft-first approach frequently allow resection of PDAC with venous involvement, even in patients with portal venous congestion and cavernous transformation. Arterial involvement does not preclude surgical resection per se, but may become surgically manageable with recent techniques of arterial divestment or arterial resection following neoadjuvant treatment.

CONCLUSION

Advanced techniques of surgical resection and vessel reconstruction provide a toolkit for curative-intent surgery in borderline resectable and locally advanced PDAC. Effects of these surgical approaches on overall survival remain to be proven with high-level clinical evidence.

Robotic versus laparoscopic distal pancreatectomy: multicentre analysis

BACKGROUND

The role of minimally invasive distal pancreatectomy is still unclear, and whether robotic distal pancreatectomy (RDP) offers benefits over laparoscopic distal pancreatectomy (LDP) is unknown because large multicentre studies are lacking. This study compared perioperative outcomes between RDP and LDP.

METHODS

A multicentre international propensity score-matched study included patients who underwent RDP or LDP for any indication in 21 European centres from six countries that performed at least 15 distal pancreatectomies annually (January 2011 to June 2019). Propensity score matching was based on preoperative characteristics in a 1 : 1 ratio. The primary outcome was the major morbidity rate (Clavien-Dindo grade IIIa or above).

RESULTS

A total of 1551 patients (407 RDP and 1144 LDP) were included in the study. Some 402 patients who had RDP were matched with 402 who underwent LDP. After matching, there was no difference between RDP and LDP groups in rates of major morbidity (14.2 versus 16.5 per cent respectively; P = 0.378), postoperative pancreatic fistula grade B/C (24.6 versus 26.5 per cent; P = 0.543) or 90-day mortality (0.5 versus 1.3 per cent; P = 0.268). RDP was associated with a longer duration of surgery than LDP (median 285 (i.q.r. 225-350) versus 240 (195-300) min respectively; P < 0.001), lower conversion rate (6.7 versus 15.2 per cent; P < 0.001), higher spleen preservation rate (81.4 versus 62.9 per cent; P = 0.001), longer hospital stay (median 8.5 (i.q.r. 7-12) versus 7 (6-10) days; P < 0.001) and lower readmission rate (11.0 versus 18.2 per cent; P = 0.004).

CONCLUSION

The major morbidity rate was comparable between RDP and LDP. RDP was associated with improved rates of conversion, spleen preservation and readmission, to the detriment of longer duration of surgery and hospital stay.

Radiological management of postoperative lymphorrhea

PURPOSE

Postoperative lymphorrhea can occur after different surgical procedures and may prolong the hospital stay due to the need for specific treatment. In this work, the therapeutic significance of the radiological management of postoperative lymphorrhea was assessed and illustrated.

METHOD

A standardized search of the literature was performed in PubMed applying the Medical Subject Headings (MeSH) term "lymphangiography." For the review, the inclusion criterion was "studies with original data on Lipiodol-based Conventional Lymphangiography (CL) with subsequent Percutaneous Lymphatic Intervention (PLI)." Different exclusion criteria were defined (e.g., studies with <15 patients). The collected data comprised of clinical background and indications, procedural aspects and types of PLI, and outcomes. In the form of a pictorial essay, each author illustrated a clinical case with CL and/or PLI.

RESULTS

Seven studies (corresponding to evidence level 4 [Oxford Centre for Evidence-Based Medicine]) accounting for 196 patients were included in the synthesis and analysis of data. Preceding surgery resulting in postoperative lymphorrhea included different surgical procedures such as extended oncologic surgery or vascular surgery. Central (e.g., chylothorax) and peripheral (e.g., lymphocele) types of postoperative lymphorrhea with a drainage volume of 100-4000 ml/day underwent CL with subsequent PLI. The intervals between "preceding surgery and CL" and between "CL and PLI" were 2-330 days and 0-5 days, respectively. CL was performed before PLI to visualize the lymphatic pathology (e.g., leakage point or inflow lymph ducts), applying fluoroscopy, radiography, and/or computed tomography (CT). In total, seven different types of PLI were identified: (1) thoracic duct (or thoracic inflow lymph duct) embolization, (2) thoracic duct (or thoracic inflow lymph duct) maceration, (3) leakage point direct embolization, (4) inflow lymph node interstitial embolization, (5) inflow lymph duct (other than thoracic) embolization, (6) inflow lymph duct (other than thoracic) maceration, and (7) transvenous retrograde lymph duct embolization. CL-associated and PLI-associated technical success rates were 97-100% and 89-100%, respectively. The clinical success rate of CL and PLI was 73-95%. CL-associated and PLI-associated major complication rates were 0-3% and 0-5%, respectively. The combined CL- and PLI-associated 30-day mortality rate was 0%, and the overall mortality rate was 3% (corresponding to six patients). In the pictorial essay, the spectrum of CL and/or PLI was illustrated.

CONCLUSION

The radiological management of postoperative lymphorrhea is feasible, safe, and effective. Standardized radiological treatments embedded in an interdisciplinary concept are a step towards improving outcomes.

Bedside hyperspectral imaging indicates a microcirculatory sepsis pattern - an observational study

INTRODUCTION

Microcirculatory alterations are key mechanisms in sepsis pathophysiology leading to tissue hypoxia, edema formation, and organ dysfunction. Hyperspectral imaging (HSI) is an emerging imaging technology that uses tissue-light interactions to evaluate biochemical tissue characteristics including tissue oxygenation, hemoglobin content and water content. Currently, clinical data for HSI technologies in critical ill patients are still limited.

METHODS AND ANALYSIS

TIVITA® Tissue System was used to measure Tissue oxygenation (StO2), Tissue Hemoglobin Index (THI), Near Infrared Perfusion Index (NPI) and Tissue Water Index (TWI) in 25 healthy volunteers and 25 septic patients. HSI measurement sites were the palm, the fingertip, and a suprapatellar knee area. Septic patients were evaluated on admission to the ICU (E), 6 h afterwards (E+6) and three times a day (t3-t9) within a total observation period of 72 h. Primary outcome was the correlation of HSI results with daily SOFA-scores.

RESULTS

Serial HSI at the three measurement sites in healthy volunteers showed a low mean variance expressing high retest reliability. HSI at E demonstrated significantly lower StO2 and NPI as well as higher TWI at the palm and fingertip in septic patients compared to healthy volunteers. StO2 and TWI showed corresponding results at the suprapatellar knee area. In septic patients, palm and fingertip THI identified survivors (E-t4) and revealed predictivity for 28-day mortality (E). Fingertip StO2 and THI correlated to SOFA-score on day 2. TWI was consistently increased in relation to the TWI range of healthy controls during the observation time. Palm TWI correlated positively with SOFA scores on day 3.

DISCUSSION

HSI results in septic patients point to a distinctive microcirculatory pattern indicative of reduced skin oxygenation and perfusion quality combined with increased blood pooling and tissue water content. THI might possess risk-stratification properties and TWI could allow tissue edema evaluation in critically ill patients.

CONCLUSION

HSI technologies could open new perspectives in microcirculatory monitoring by visualizing oxygenation and perfusion quality combined with tissue water content in critically ill patients - a prerequisite for future tissue perfusion guided therapy concepts in intensive care medicine.

Radiological evaluation of pancreatic cancer: What is the significance of arterial encasement >180° after neoadjuvant treatment?

PURPOSE

This study aimed to evaluate contrast-enhanced computed tomography (CE-CT) features for prediction of arterial tumor invasion in pancreatic cancer (PDAC) patients in the event of arterial encasement >180° after neoadjuvant (radio-)chemotherapy (NAT).

METHODS

Seventy PDAC patients with seventy-five arteries showing encasement >180° after completion of NAT were analyzed. All patients underwent surgical exploration with either tumor resection including arterial resection, periadventitial dissection (arterial divestment) or confirmation of locally irresectable disease. CE-CT scans were assessed regarding tumor extent and artery-specific imaging features. The results were analyzed on a per-artery basis. Based on the intraoperative and histopathological findings, encased arteries were classified as either invaded or non-invaded.

RESULTS

Eighteen radiologically encased arteries were resected; of these, nine had pathologic evidence for tumor invasion. In 42 encased arteries, the tumor could be removed by arterial divestment. In 13 patients with 15 encased arteries, the tumor was deemed technically irresectable. Median tumor size, length of solid soft tissue contact, and degree of circumferential contiguity by solid soft tissue along the artery in CE-CT were significantly lower in the non-invaded than in the invaded artery group (p ≤ 0.017). Imaging features showed moderate accuracies for prediction of arterial invasion (≤72.0 %). The thresholds ≤26 mm for post-NAT solid soft tissue contact and ≤270° for circumferential contiguity by solid soft tissue had high negative predictive values (≥87.5 %).

CONCLUSION

Although post-NAT prediction of arterial invasion remains difficult, arteries with ≤270° contiguity by soft tissue and arteries with ≤26 mm length of solid soft tissue contact are unlikely to be invaded, with possible implications for surgical planning.

Laparoscopic versus open extended radical left pancreatectomy for pancreatic ductal adenocarcinoma: an international propensity-score matched study

BACKGROUND

A radical left pancreatectomy in patients with pancreatic ductal adenocarcinoma (PDAC) may require extended, multivisceral resections. The role of a laparoscopic approach in extended radical left pancreatectomy (ERLP) is unclear since comparative studies are lacking. The aim of this study was to compare outcomes after laparoscopic vs open ERLP in patients with PDAC.

METHODS

An international multicenter propensity-score matched study including patients who underwent either laparoscopic or open ERLP (L-ERLP; O-ERLP) for PDAC was performed (2007-2015). The ISGPS definition for extended resection was used. Primary outcomes were overall survival, margin negative rate (R0), and lymph node retrieval.

RESULTS

Between 2007 and 2015, 320 patients underwent ERLP in 34 centers from 12 countries (65 L-ERLP vs. 255 O-ERLP). After propensity-score matching, 44 L-ERLP could be matched to 44 O-ERLP. In the matched cohort, the conversion rate in L-ERLP group was 35%. The L-ERLP R0 resection rate (matched cohort) was comparable to O-ERLP (67% vs 48%; P = 0.063) but the lymph node yield was lower for L-ERLP than O-ERLP (median 11 vs 19, P = 0.023). L-ERLP was associated with less delayed gastric emptying (0% vs 16%, P = 0.006) and shorter hospital stay (median 9 vs 13 days, P = 0.005), as compared to O-ERLP. Outcomes were comparable for additional organ resections, vascular resections (besides splenic vessels), Clavien-Dindo grade ≥ III complications, or 90-day mortality (2% vs 2%, P = 0.973). The median overall survival was comparable between both groups (19 vs 20 months, P = 0.571). Conversion did not worsen outcomes in L-ERLP.

CONCLUSION

The laparoscopic approach may be used safely in selected patients requiring ERLP for PDAC, since morbidity, mortality, and overall survival seem comparable, as compared to O-ERLP. L-ERLP is associated with a high conversion rate and reduced lymph node yield but also with less delayed gastric emptying and a shorter hospital stay, as compared to O-ERLP.

Percutaneous afferent lymphatic vessel sclerotherapy for postoperative lymphatic leakage after previous ineffective therapeutic transpedal lymphangiography

BACKGROUND

To demonstrate the efficacy of percutaneous computed tomography (CT)-guided afferent lymphatic vessel sclerotherapy (ALVS) in the treatment of postoperative lymphatic leakage (LL) after ineffective therapeutic transpedal lymphangiography (TL).

METHODS

A retrospective review in this institute involving 201 patients was conducted from May 2011 to September 2018. Patients diagnosed with postoperative LL undergoing ineffective therapeutical TL before the performance of percutaneous CT-guided ALVS were involved. Technical success and clinical success of TL and ALVS were established. The technical success and efficacy of ALVS in the treatment of postoperative LL after ineffective therapeutic TL were assessed. The clinical success rate of ALVS is also assessed, and the complications are reviewed.

RESULTS

In total, nine patients were involved including three patients (33.3%) presented with chylothorax, three patients (33.3%) presented with inguinal lymphatic fistula/lymphocele, and three patients (33.3%) presented with lymphatic fistula in the thigh; 27 ± 18 days (mean ± standard deviation) after surgery, therapeutic TL was successfully performed and showed definite afferent lymphatic vessel and leakage site in all the patients. Due to clinical failure after TLs, the following ALVS was performed with a mean interval of 12 ± 8 days after TL. The technical success rate was 9/9 (100.0%, 95% confidence interval [CI] 63.1-100.0%). An average of 2.7 ± 1.3 mL 95% ethanol as sclerosant agent was injected during the procedure. The clinical success was observed in 8 of the 9 patients (88.9%, 95% CI 51.8-99.7%) with a time between ALVS and the LL cure of 8 ± 6 days. No complications were reported.

CONCLUSIONS

Our results showed the role of percutaneous CT-guided ALVS as a safe, feasible, and effective salvage treatment for postoperative LL after ineffective TL.

The roles of iodized oil-based lymphangiography and post-lymphangiographic computed tomography for specific lymphatic intervention planning in patients with postoperative lymphatic fistula: a literature review and case series

In the management of patients with postoperative lymphatic fistula (LF) in different locations, iodized oil-based lymphangiography (LAG) from trans-pedal or intranodal route is an established diagnostic approach with the potential to plan further interventional treatments. However, specific lymphatic interventions are indicated depending on different locations and morphologies of the LF. After a systematic literature review, four types of interventions can be considered, including direct leakage embolization/sclerotherapy (DLE/DLS), percutaneous afferent lymphatic vessel embolization (ALVE), percutaneous afferent lymphatic vessels disruption/sclerotherapy (ALVD/ALVS), and trans-afferent nodal embolization (TNE). In the iodized oil-based LAG, three potential lymphatic targets including confined leakage, definite afferent LVs, and definite closest afferent LNs should be comprehensively assessed. For optimal prospective treatment planning for LF, iodized oil-based post-lymphangiographic computed tomography (post-LAG CT) is a useful complement to the conventional iodized oil-based LAG, which can be performed easily after LAG. This review article summarized the current evidence of the specific lymphatic interventions in patients with postoperative LF and explored the potential benefits of post-LAG CT in the intervention planning from a case series.

Predictors for Survival in an International Cohort of Patients Undergoing Distal Pancreatectomy for Pancreatic Ductal Adenocarcinoma

Background

Surgical factors, including resection of Gerota’s fascia, R0-resection, and lymph node yield, may be associated with survival after distal pancreatectomy (DP) for pancreatic ductal adenocarcinoma (PDAC), but evidence from large multicenter studies is lacking. This study aimed to identify predictors for overall survival after DP for PDAC, especially those related to surgical technique.

Patients and Methods

Data from an international retrospective cohort including patients from 11 European countries and the USA who underwent DP for PDAC (2007–2015) were analyzed. Cox proportional hazard analyses were performed and included Gerota’s fascia resection, R0 resection, lymph node ratio, extended resection, and a minimally invasive approach.

Results

Overall, 1200 patients from 34 centers with median follow-up of 15 months [interquartile range (IQR) 5–31 months] and median survival period of 30 months [95% confidence interval (CI), 27–33 months] were included. Gerota’s fascia resection [hazard ratio (HR) 0.74; p = 0.019], R0 resection (HR 0.70; p = 0.006), and decreased lymph node ratio (HR 0.28; p < 0.001) were associated with improved overall survival, whereas extended resection (HR 1.75; p < 0.001) was associated with worse overall survival. A minimally invasive approach did not improve survival as compared with an open approach (HR 1.14; p = 0.350). Adjuvant chemotherapy (HR 0.67; p = 0.003) was also associated with improved overall survival.

Conclusions

This international cohort identified Gerota’s fascia resection, R0 resection, and decreased lymph node ratio as factors associated with improved overall survival during DP for PDAC. Surgeons should strive for R0 resection and adequate lymphadenectomy and could also consider Gerota’s fascia resection in their routine surgical approach.

Electronic supplementary material

The online version of this article (10.1245/s10434-020-08658-5) contains supplementary material, which is available to authorized users.

Endoscopic versus surgical treatment for infected necrotizing pancreatitis: a systematic review and meta-analysis of randomized controlled trials

OBJECTIVE

To compare outcomes of endoscopic and surgical treatment for infected necrotizing pancreatitis (INP) based on results of randomized controlled trials (RCT).

BACKGROUND

Treatment of INP has changed in the last two decades with adoption of interventional, endoscopic and minimally invasive surgical procedures for drainage and necrosectomy. However, this relies mostly on observational studies.

METHODS

We performed a systematic review following Cochrane and PRISMA guidelines and AMSTAR-2 criteria and searched CENTRAL, Medline and Web of Science. Randomized controlled trails that compared an endoscopic treatment to a surgical treatment for patients with infected walled-off necrosis and included one of the main outcomes were eligible for inclusion. The main outcomes were mortality and new onset multiple organ failure. Prospero registration ID: CRD42019126033 RESULTS: Three RCTs with 190 patients were included. Intention to treat analysis showed no difference in mortality. However, patients in the endoscopic group had statistically significant lower odds of experiencing new onset multiple organ failure (odds ratio (OR) confidence interval [CI] 0.31 [0.10, 0.98]) and were statistically less likely to suffer from perforations of visceral organs or enterocutaneous fistulae (OR [CI] 0.31 [0.10, 0.93]), and pancreatic fistulae (OR [CI] 0.09 [0.03, 0.28]). Patients with endoscopic treatment had a statistically significant lower mean hospital stay (Mean difference [CI] - 7.86 days [- 14.49, - 1.22]). No differences in bleeding requiring intervention, incisional hernia, exocrine or endocrine insufficiency or ICU stay were apparent. Overall certainty of evidence was moderate.

CONCLUSION

There seem to be possible benefits of endoscopic treatment procedure. Given the heterogenous procedures in the surgical group as well as the low amount of randomized evidence, further studies are needed to evaluate the combination of different approaches and appropriate timepoints for interventions.

Functional outcomes after laparoscopic versus robotic-assisted rectal resection: a systematic review and meta-analysis

Surgical resection is crucial for curative treatment of rectal cancer. Through multidisciplinary treatment, including radiochemotherapy and total mesorectal excision, survival has improved substantially. Consequently, more patients have to deal with side effects of treatment. The most recently introduced surgical technique is robotic-assisted surgery (RAS) which seems equally effective in terms of oncological control compared to laparoscopy. However, RAS enables further advantages which maximize the precision of surgery, thus providing better functional outcomes such as sexual function or contience without compromising oncological results. This review was done according to the PRISMA and AMSTAR-II guidelines and registered with PROSPERO (CRD42018104519). The search was planned with PICO criteria and conducted on Medline, Web of Science and CENTRAL. All screening steps were performed by two independent reviewers. Inclusion criteria were original, comparative studies for laparoscopy vs. RAS for rectal cancer and reporting of functional outcomes. Quality was assessed with the Newcastle–Ottawa scale. The search retrieved 9703 hits, of which 51 studies with 24,319 patients were included. There was a lower rate of urinary retention (non-RCTs: Odds ratio (OR) [95% Confidence Interval (CI)] 0.65 [0.46, 0.92]; RCTs: OR[CI] 1.29[0.08, 21.47]), ileus (non-RCTs: OR[CI] 0.86[0.75, 0.98]; RCTs: OR[CI] 0.80[0.33, 1.93]), less urinary symptoms (non-RCTs mean difference (MD) [CI] − 0.60 [− 1.17, − 0.03]; RCTs: − 1.37 [− 4.18, 1.44]), and higher quality of life for RAS (only non-RCTs: MD[CI]: 2.99 [2.02, 3.95]). No significant differences were found for sexual function (non-RCTs: standardized MD[CI]: 0.46[− 0.13, 1.04]; RCTs: SMD[CI]: 0.09[− 0.14, 0.31]). The current meta-analysis suggests potential benefits for RAS over laparoscopy in terms of functional outcomes after rectal cancer resection. The current evidence is limited due to non-randomized controlled trials and reporting of functional outcomes as secondary endpoints.

Meta-analysis of recurrence pattern after resection for pancreatic cancer

Background

Initial recurrence mapping of resected pancreatic ductal adenocarcinoma (PDAC) could help in stratifying patient subpopulations for optimal postoperative follow-up. The aim of this systematic review and meta-analysis was to investigate the initial recurrence patterns of PDAC and to correlate them with clinicopathological factors.

Methods

MEDLINE and Web of Science databases were searched systematically for studies reporting first recurrence patterns after PDAC resection. Data were extracted from the studies selected for inclusion. Pooled odds ratios (ORs) and 95 per cent confidence intervals were calculated to determine the clinicopathological factors related to the recurrence sites. The weighted average of median overall survival was calculated.

Results

Eighty-nine studies with 17 313 patients undergoing PDAC resection were included. The weighted median rates of initial recurrence were 20·8 per cent for locoregional sites, 26·5 per cent for liver, 11·4 per cent for lung and 13·5 per cent for peritoneal dissemination. The weighted median overall survival times were 19·8 months for locoregional recurrence, 15·0 months for liver recurrence, 30·4 months for lung recurrence and 14·1 months for peritoneal dissemination. Meta-analysis revealed that R1 (direct) resection (OR 2·21, 95 per cent c.i. 1·12 to 4·35), perineural invasion (OR 5·19, 2·79 to 9·64) and positive peritoneal lavage cytology (OR 5·29, 3·03 to 9·25) were significantly associated with peritoneal dissemination as initial recurrence site. Low grade of tumour differentiation was significantly associated with liver recurrence (OR 4·15, 1·71 to 10·07).

Conclusion

Risk factors for recurrence patterns after surgery could be considered for specific surveillance and treatments for patients with pancreatic cancer.

Meta-analysis of effect of routine enteral nutrition on postoperative outcomes after pancreatoduodenectomy

BACKGROUND

The optimal nutritional treatment after pancreatoduodenectomy is still unclear. The aim of this meta-analysis was to investigate the impact of routine enteral nutrition following pancreatoduodenectomy on postoperative outcomes.

METHODS

RCTs comparing enteral nutrition (regular oral intake with routine tube feeding) with non-enteral nutrition (regular oral intake with or without parenteral nutrition) after pancreatoduodenectomy were sought systematically in the MEDLINE, Cochrane Library and Web of Science databases. Postoperative data were extracted. Random-effects meta-analyses were performed to compare postoperative outcomes in the two arms, and pooled odds ratios (ORs) or mean differences (MDs) were calculated with 95 per cent confidence intervals. In subgroup analyses, the routes of nutrition were assessed. Percutaneous tube feeding and nasojejunal tube feeding were each compared with parenteral nutrition.

RESULTS

Eight RCTs with a total of 955 patients were included. Enteral nutrition was associated with a lower incidence of infectious complications (OR 0·66, 95 per cent c.i. 0·43 to 0·99; P = 0·046) and a shorter length of hospital stay (MD -2·89 (95 per cent c.i. -4·99 to -0·80) days; P < 0·001) than non-enteral nutrition. Percutaneous tube feeding had a lower incidence of infectious complications (OR 0·47, 0·25 to 0·87; P = 0·017) and a shorter hospital stay (MD -1·56 (-2·13 to -0·98) days; P < 0·001) than parenteral nutrition (3 RCTs), whereas nasojejunal tube feeding was not associated with better postoperative outcomes (2 RCTs).

CONCLUSION

As a supplement to regular oral diet, routine enteral nutrition, especially via a percutaneous enteral tube, may improve postoperative outcomes after pancreatoduodenectomy.

Validation of at least 1 mm as cut-off for resection margins for pancreatic adenocarcinoma of the body and tail

BACKGROUND

The definition of resection margin (R) status in pancreatic cancer is under debate. Although a margin of at least 1 mm is an independent predictor of survival after resection for pancreatic head cancer, its relevance to pancreatic body and tail cancers remains unclear. This study aimed to validate R status based on a 1-mm tumour-free margin as a prognostic factor for resected adenocarcinoma involving the pancreatic body and tail.

METHODS

Patients who underwent distal or total pancreatectomy for adenocarcinomas of the pancreatic body and tail between January 2006 and December 2014 were identified from a prospective database. Resection margins were evaluated using a predefined cut-off of 1 mm. Rates of R0, R1 with invasion within 1 mm of the margin (R1 less than 1 mm), and R1 with direct invasion of the resection margin (R1 direct) were determined, and overall survival in each group assessed by Kaplan-Meier analysis. Univariable and multivariable Cox regression analyses were performed to identify predictors of survival.

RESULTS

R0 resection was achieved in 107 (23·5 per cent) and R1 in 348 (76·5 per cent) of 455 patients. Among R1 resections, invasion within 1 mm of the margin was found in 104 (22·9 per cent) and direct invasion in 244 (53·6 per cent). The R0 rate was 28·9 per cent after distal and 18·6 per cent after total pancreatectomy. In the total cohort, median survival times for patients with R0, R1 (less than 1 mm) and R1 (direct) status were 62·4, 24·6 and 17·2 months respectively, with 5-year survival rates of 52·6, 16·8 and 13·0 per cent (P < 0·001). In patients who received adjuvant chemotherapy, respective median survival times were 68·6, 32·8 and 21·4 months, with 5-year survival rates of 56, 22 and 16·0 per cent (P < 0·001). In multivariable analysis, R status was independently associated with survival.

CONCLUSION

A cut-off of at least 1 mm for evaluation of resection margins is an independent determinant of survival after resection of adenocarcinomas of the pancreatic body and tail.

Meta-analysis of delayed gastric emptying after pylorus-preserving versus pylorus-resecting pancreatoduodenectomy

BACKGROUND

Delayed gastric emptying (DGE) is a frequent complication after pylorus-preserving pancreatoduodenectomy. Recent studies have suggested that resection of the pylorus is associated with decreased rates of DGE. However, superiority of pylorus-resecting pancreatoduodenectomy was not shown in a recent RCT. This meta-analysis summarized evidence of the effectiveness and safety of pylorus-preserving compared with pylorus-resecting pancreatoduodenectomy.

METHODS

RCTs and non-randomized studies comparing outcomes of pylorus-preserving and pylorus-resecting pancreatoduodenectomy were searched systematically in MEDLINE, Web of Science and CENTRAL. Random-effects meta-analyses were performed and the results presented as weighted odds ratios (ORs) or mean differences with their corresponding 95 per cent confidence intervals. Subgroup analyses were performed to account for interstudy heterogeneity between RCTs and non-randomized studies.

RESULTS

Three RCTs and eight non-randomized studies with a total of 992 patients were included. Quantitative synthesis across all studies showed superiority for pylorus-resecting pancreatoduodenectomy regarding DGE (OR 2·71, 95 per cent c.i. 1·48 to 4·96; P = 0·001) and length of hospital stay (mean difference 3·26 (95 per cent c.i. -1·04 to 5·48) days; P = 0·004). Subgroup analyses including only RCTs showed no significant statistical differences between the two procedures regarding DGE, and for all other effectiveness and safety measures.

CONCLUSION

Pylorus-resecting pancreatoduodenectomy is not superior to pylorus-preserving pancreatoduodenectomy for reducing DGE or other relevant complications.

Predictive performance of factors associated with malignancy in intraductal papillary mucinous neoplasia of the pancreas

Background

Estimation of the risk of malignancy in intraductal papillary mucinous neoplasia (IPMN) of the pancreas is a clinical challenge. Several routinely used clinical factors form the basis of the current consensus guidelines. This study aimed to determine the predictive values of the most commonly assessed risk factors.

Methods

A meta-analysis of individual risk factors of malignancy in IPMN was performed. Contingency tables were derived from these data, and sensitivity, specificity, negative and positive predictive values, and diagnostic odds ratios (DOR) were determined. Hierarchical summary receiver operating characteristic (HSROC) curves for each factor were calculated and the respective area under the curve (AUC) was assessed.

Results

A total of 3443 studies were screened initially. Analysis of recent literature revealed 60 studies with 13 relevant risk factors including clinical, serological and radiological parameters. The largest area under the HSROC curve was found for weight loss (0·84) and jaundice/raised bilirubin level (0·80), followed by increased carcinoembryonic antigen (CEA) (0·79) or carbohydrate antigen (CA) 19-9 (0·78) levels. The most sensitive factors were patient age (71 per cent) and mural nodules (65 per cent), and jaundice/raised bilirubin level (97 per cent) and increased CEA level (95 per cent) were most specific. None of the analysed factors reached a positive or negative level of prediction beyond 90 per cent.

Conclusion

None of the established criteria safely distinguishes malignant from non-malignant lesions.

[Branch duct intraductal papillary mucinous neoplasm - surgical approach]

Due to increasing precision of modern imaging modalities, intraductal papillary mucinous neoplasms (IPMN) of the pancreas are found with increasing prevalence. Despite their malignant potential IPMN are often kept under surveillance and are not immediately resected. The 2012 International Consensus Guidelines of Fukuoka have been widely accepted for the management of IPMN. They recommend surgical resection for branch duct IPMN with "high risk stigmata", while branch duct IPMN with "worrisome features" should undergo observation without immediate resection. Consequently, patients with asymptomatic branch duct IPMN and a presumed low malignant potential mostly undergo primary surveillance to avoid surgery-related morbidity and mortality following pancreatic resection; however, with respect to the cumulative risk of malignant transformation over time, surgical resection might also be indicated for patients with branch duct IPMN with "worrisome features". This article discusses the indications for surgery and different options of resection of branch duct IPMN.

Management of patients with pancreatic cystic lesions: A case-based survey

BACKGROUND

Pancreatic cystic lesions (PCL), including intraductal papillary mucinous neoplasia (IPMN), harbor different malignant potential and the optimal management is often challenging. The present study aims to depict the compliance of experts with current consensus guidelines and the accuracy of treatment recommendations stratified by the medical specialty and hospital volume.

METHODS

An international survey was conducted using a set of 10 selected cases of PCL that were presented to a cohort of international experts on pancreatology. All presented cases were surgically resected between 2004 and 2015 and histopathological examination was available. Accuracy of the treatment recommendations was based on the European and international consensus guideline algorithms, and the histopathological result.

RESULTS

The response rate of the survey was 26% (46 of 177 contacted experts), consisting of 70% surgeons and 30% gastroenterologists/oncologists (GI/Onc). In the case of main-duct IPMN (MD-IPMN), surgeons preferred more often the surgical approach in comparison with the GI/Onc (55 versus 44%). The mean accuracy rate based on the European and international consensus guidelines, and the histopathological result, were 71/76/38% (surgeons), and 70/73/34% (GI/Onc), respectively. High-volume centers achieved insignificantly higher accuracy scores with regard to the histopathology. Small branch-duct IPMN with cysts <2 cm and malignant potential were not identified by the guideline algorithms.

CONCLUSION

The survey underlines the complexity of treatment decisions for patients with PCL; less than 40% of the recommendations were in line with the final histopathology in this selected case panel. Experts and consensus guidelines may fail to predict malignant potential in small PCL.

Prospective trial to evaluate the prognostic value of different nutritional assessment scores in pancreatic surgery (NURIMAS Pancreas)

BACKGROUND

Preoperative nutritional status has an impact on patients' clinical outcome. For pancreatic surgery, however, it is unclear which nutritional assessment scores adequately assess malnutrition associated with postoperative outcome.

METHODS

Patients scheduled for elective pancreatic surgery at the University of Heidelberg were screened for eligibility. Twelve nutritional assessment scores were calculated before operation, and patients were categorized as either at risk or not at risk for malnutrition by each score. The postoperative course was monitored prospectively by assessors blinded to the nutritional status. The primary endpoint was major complications evaluated for each score in a multivariable analysis corrected for known risk factors in pancreatic surgery.

RESULTS

Overall, 279 patients were analysed. A major complication occurred in 61 patients (21·9 per cent). The proportion of malnourished patients differed greatly among the scores, from 1·1 per cent (Nutritional Risk Index) to 79·6 per cent (Nutritional Risk Classification). In the multivariable analysis, only raised amylase level in drainage fluid on postoperative day 1 (odds ratio (OR) 4·91, 95 per cent c.i. 1·10 to 21·84; P = 0·037) and age (OR 1·05, 1·02 to 1·09; P = 0·005) were significantly associated with major complications; none of the scores was associated with, or predicted, postoperative complications.

CONCLUSION

None of the nutritional assessment scores defined malnutrition relevant to complications after pancreatic surgery and these scores may thus be abandoned.

Meta-analysis of prophylactic abdominal drainage in pancreatic surgery

BACKGROUND

Intra-abdominal drains are frequently used after pancreatic surgery whereas their benefit in other gastrointestinal operations has been questioned. The objective of this meta-analysis was to compare abdominal drainage with no drainage after pancreatic surgery.

METHODS

PubMed, the Cochrane Library and Web of Science electronic databases were searched systematically to identify RCTs comparing abdominal drainage with no drainage after pancreatic surgery. Two independent reviewers critically appraised the studies and extracted data. Meta-analyses were performed using a random-effects model. Odds ratios (ORs) were calculated to aggregate dichotomous outcomes, and weighted mean differences for continuous outcomes. Summary effect measures were presented together with their 95 per cent confidence intervals.

RESULTS

Some 711 patients from three RCTs were included. The 30-day mortality rate was 2·0 per cent in the drain group versus 3·4 per cent after no drainage (OR 0·68, 95 per cent c.i. 0·26 to 1·79; P = 0·43). The morbidity rate was 65·6 per cent in the drain group and 62·0 per cent in the no-drain group (OR 1·17, 0·86 to 1·60; P = 0·31). Clinically relevant pancreatic fistulas were seen in 11·5 per cent of patients in the drain group and 9·5 per cent in the no-drain group. Reinterventions, intra-abdominal abscesses and duration of hospital stay also showed no significant difference between the two groups.

CONCLUSION

Pancreatic resection with, or without abdominal drainage results in similar rates of mortality, morbidity and reintervention.

Staging of pancreatic cancer based on the number of positive lymph nodes

BACKGROUND

The International Study Group on Pancreatic Surgery has stated that at least 12 lymph nodes should be evaluated for staging of pancreatic cancer. The aim of this population-based study was to evaluate whether the number of positive lymph nodes refines staging.

METHODS

Patients who underwent pancreatectomy for stage I-II pancreatic cancer between 2004 and 2012 were identified from the Surveillance, Epidemiology, and End Results database. The predictive value of the number of positive lymph nodes for survival was assessed by generalized receiver operating characteristic (ROC) curve analysis and propensity score-adjusted Cox regression analysis.

RESULTS

Some 5036 patients were included, with a median of 18 (i.q.r. 15-24) lymph nodes examined. Positive lymph nodes were found in 3555 patients (70·6 per cent). The median duration of follow-up was 15 (i.q.r. 8-28) months. ROC curve analysis revealed that two positive lymph nodes best discriminated overall survival. Patients with one or two positive lymph nodes (pN1a) and those with three or more positive lymph nodes (pN1b) had an increased risk of overall mortality compared with patients who were node-negative (pN0): hazard ratio (HR) 1·47 (95 per cent c.i. 1·33 to 1·64) and HR 2·01 (1·82 to 2·22) respectively. These findings were confirmed by propensity score-adjusted Cox regression analysis. The 5-year overall survival rates were 39·8 (95 per cent c.i. 36·5 to 43·3) per cent for patients with pN0, 21·0 (18·6 to 23·6) per cent for those with pN1a and 11·4 (9·9 to 13·3) per cent for patients with pN1b disease.

CONCLUSION

The number of positive lymph nodes in the resection specimen is a prognostic factor in patients with pancreatic cancer.

Incidence, risk factors and clinical implications of chyle leak after pancreatic surgery

Background

Chyle leak is a well known but poorly characterized complication after pancreatic surgery. Available data on incidence, risk factors and clinical significance of chyle leak are highly heterogeneous.

Methods

For this cohort study all patients who underwent pancreatic surgery between January 2008 and December 2012 were identified from a prospective database. Chyle leak was defined as any drainage output with triglyceride content of 110 mg/dl or more. Risk factors for chyle leak were assessed by univariable and multivariable analyses. The clinical relevance of chyle leak was evaluated using hospital stay and resolution by 14 days for short-term outcome and overall survival for long-term outcome.

Results

Chyle leak developed in 346 (10·4 per cent) of 3324 patients. Pre-existing diabetes, resection for malignancy, distal pancreatectomy, duration of surgery 180 min or longer, and concomitant pancreatic fistula or abscess were independent risk factors for chyle leak. Both isolated chyle leak and coincidental chyle leak (with other intra-abdominal complications) were associated with prolonged hospital stay. Some 178 (87·7 per cent) of 203 isolated chyle leaks and 90 (70·3 per cent) of 128 coincidental chyle leaks resolved with conservative management within 14 days. Initial and maximum drainage volumes were associated with duration of hospital stay and success of therapy by 14 days. Impact on survival was restricted to chyle leaks that persisted at 14 days in patients with cancer undergoing palliative surgery.

Conclusion

Chyle leak is a relevant complication, with an incidence of more than 10 per cent after pancreatic surgery, and has a major impact on hospital stay. Drainage volume is associated with hospital stay and success of therapy.

Outcomes after extended pancreatectomy in patients with borderline resectable and locally advanced pancreatic cancer

Background

In the recent International Study Group of Pancreatic Surgery (ISGPS) consensus on extended pancreatectomy, several issues on perioperative outcome and long-term survival remained unclear. Robust data on outcomes are sparse. The present study aimed to assess the outcome of extended pancreatectomy for borderline resectable and locally advanced pancreatic cancer.

Methods

A consecutive series of patients with primary pancreatic adenocarcinoma undergoing extended pancreatectomies, as defined by the new ISGPS consensus, were compared with patients who had a standard pancreatectomy. Univariable and multivariable analysis was performed to identify risk factors for perioperative mortality and characteristics associated with survival. Long-term outcome was assessed by means of Kaplan–Meier analysis.

Results

The 611 patients who had an extended pancreatectomy had significantly greater surgical morbidity than the 1217 patients who underwent a standard resection (42·7 versus 34·2 per cent respectively), and higher 30-day mortality (4·3 versus 1·8 per cent) and in-hospital mortality (7·5 versus 3·6 per cent) rates. Operating time of 300 min or more, extended total pancreatectomy, and ASA fitness grade of III or IV were associated with increased in-hospital mortality in multivariable analysis, whereas resections involving the colon, portal vein or arteries were not. Median survival and 5-year overall survival rate were reduced in patients having extended pancreatectomy compared with those undergoing a standard resection (16·1 versus 23·6 months, and 11·3 versus 20·6 per cent, respectively). Older age, G3/4 tumours, two or more positive lymph nodes, macroscopic positive resection margins, duration of surgery of 420 min or above, and blood loss of 1000 ml or more were independently associated with decreased overall survival.

Conclusion

Extended resections are associated with increased perioperative morbidity and mortality, particularly when extended total pancreatectomy is performed. Favourable long-term outcome is achieved in some patients.

Dual-Energy Perfusion-CT in Recurrent Pancreatic Cancer - Preliminary Results

PURPOSE

To evaluate the diagnostic performance of dual energy (DE) perfusion-CT for the differentiation between postoperative soft-tissue formation and tumor recurrence in patients after potentially curative pancreatic cancer resection.

MATERIAL AND METHODS

24 patients with postoperative soft-tissue formation in the conventional regular follow-up CT acquisition after pancreatic cancer resection with curative intent were included prospectively. They were examined with a 64-row dual-source CT using a dynamic sequence of 34 DE acquisitions every 1.5 s (80 ml of iodinated contrast material, 370 mg/ml, flow rate 5 ml/s). Weighted average (linearly blended M0.5) 120kVp-equivalent dual-energy perfusion image data sets were evaluated with a body-perfusion CT tool (see above) for estimating blood flow, permeability, and blood volume. Diagnosis was confirmed by histological study (n = 4) and by regular follow-up.

RESULTS

Final diagnosis was local recurrence of pancreatic cancer in 15 patients and unspecific postoperative tissue formation in 9 patients. The blood-flow values for recurrence tissue trended to be lower compared to postoperative tissue formation with 16.6 ml/100 ml/min and 24.7 ml/100 ml/min, respectively for weighted average 120kVp-equivalent image data, which was not significant (n.s.) (p = 0.06, significance level 0.05). Permeability- and blood-volume values were only slightly lower in recurrence tissue (n.s.).

CONCLUSION

DE perfusion-CT is feasible in patients after pancreatic cancer resection and a promising functional imaging technique. As only a trend for lower perfusion values in local recurrence compared to unspecific postoperative alterations was found, the perfusion differences are not yet sufficient to differentiate between malignancy and unspecific postoperative alterations for this new technique. Further studies and technical improvements are needed to generate reliable data for this clinically highly relevant differentiation.

KEY POINTS

• DE Perfusion CT is feasible in patients after pancreatic cancer resection.• While reliable differentiation of unspecific postoperative tissue formation from recurrent malignancy cannot be achieved yet, it is within reach.• DE Perfusion CT has the potential to overcome todays limitations of pure morphological diagnosis of recurrent pancreatic cancer. Citation Format: • Fritz F, Skornitzke S, Hackert T et al. Dual-Energy Perfusion-CT in Recurrent Pancreatic Cancer - Preliminary RESULTS. Fortschr Röntgenstr 2016; 188: 559 - 565.

Risk of pancreatic fistula after enucleation of pancreatic tumours

Background

Enucleation is used increasingly for small pancreatic tumours. Data on perioperative outcome after pancreatic enucleation, especially regarding the significance and risk factors associated with postoperative pancreatic fistula (POPF), are limited. This study aimed to assess risk-dependent perioperative outcome after pancreatic enucleation, with a focus on POPF.

Methods

Patients undergoing enucleation for pancreatic lesions between October 2001 and February 2014 were identified from a prospective database. A detailed analysis of morbidity was performed. Risk factors for POPF were assessed by univariable and multivariable analyses.

Results

Of 166 enucleations, 94 (56·6 per cent) were performed for cystic and 72 (43·4 per cent) for solid lesions. Morbidity was observed in 91 patients (54·8 per cent). Severe complications occurred in 30 patients (18·1 per cent), and one patient (0·6 per cent) died. Reoperation was necessary in nine patients (5·4 per cent). POPF was the main determinant of outcome and occurred in 68 patients (41·0 per cent): grade A POPF, 34 (20·5 per cent); grade B, ten (6·0 per cent); and grade C, 24 (14·5 per cent). Risk factors independently associated with POPF were: cystic tumour, localization in the pancreatic tail, history of pancreatitis and cardiac co-morbidity. Only cystic morphology was independently associated with clinically relevant POPF (grade B or C), occurring after enucleation in 25 (27 per cent) of 94 patients with cystic tumours versus nine (13 per cent) of 72 patients with solid tumours. Tumour size and distance to the main duct were not associated with risk of POPF.

Conclusion

Enucleation is a safe procedure in appropriately selected patients with a low rate of severe complications. POPF is the main determinant of outcome and is more frequent after the enucleation of cystic lesions.

Meta-analysis of surgical outcome after enucleation versus standard resection for pancreatic neoplasms

BACKGROUND

Pancreatic enucleation is a tissue-sparing approach to pancreatic neoplasms and may result in better postoperative pancreatic function than standard pancreatic resection. The objective of this review was to compare the postoperative outcome after pancreatic enucleation versus standard resection.

METHODS

MEDLINE, Embase and the Cochrane Library were searched systematically until February 2015 to identify studies comparing the outcome of enucleation versus standard resection for pancreatic neoplasms. After critical appraisal, meta-analysis was performed and the findings were presented as odds ratios or weighted mean differences with corresponding 95 per cent c.i.

RESULTS

Twenty-two observational studies (1148 patients) were included. Duration of surgery (P < 0.001), blood loss (P < 0.001), length of hospital stay (P = 0.04), and postoperative endocrine (P < 0.001) and exocrine (P = 0.01) insufficiency were lower after enucleation than after standard resection. Mortality (P = 0.44), overall complications (P = 0.74), reoperation rate (P = 0.93) and delayed gastric emptying (P = 0.15) were not significantly different between the two approaches. The overall rate of postoperative pancreatic fistula (POPF) was higher after enucleation than after standard resection (P < 0.001). However, the raised POPF rate did not result in higher mortality or overall morbidity. Sensitivity analysis of high-volume studies (total of more than 20 enucleations and more than 4 per year) showed that, in specialized centres, enucleation can be performed with no increased risk of POPF (P = 0.12).

CONCLUSION

Compared with standard resection, pancreatic enucleation can be performed effectively and with comparable safety in high-volume institutions. Enucleation should be considered instead of standard resection for selected pancreatic neoplasms.

Meta-analysis of complication rates for single-loop versus dual-loop (Roux-en-Y) with isolated pancreaticojejunostomy reconstruction after pancreaticoduodenectomy

Background

Postoperative pancreatic fistula is one of the most important and potentially severe complications after partial pancreaticoduodenectomy. In this context, the reduction of postoperative pancreatic fistula by means of a dual-loop (Roux-en-Y) reconstruction with isolation of the pancreaticojejunostomy from biliary drainage has been evaluated in several studies. This systematic review and meta-analysis summarizes evidence of effectiveness and safety of the isolation of the pancreaticojejunostomy compared with conventional single-loop reconstruction.

Methods

Randomized clinical trials (RCTs) and controlled clinical trials (CCTs) comparing outcomes of dual-loop reconstruction with isolated pancreaticojejunostomy and single-loop reconstruction were searched according to PRISMA guidelines. Random-effects meta-analyses were performed and the results presented as weighted risk ratios or mean differences with their corresponding 95 per cent c.i.

Results

Of 83 trials screened for eligibility, three RCTs and four CCTs including a total of 802 patients were finally included. Quantitative synthesis showed no significant statistical difference between the two procedures regarding postoperative pancreatic fistula, delayed gastric emptying, haemorrhage, intra-abdominal fluid collection or abscess, bile leakage, wound infection, pneumonia, overall morbidity, mortality, reinterventions, reoperations, perioperative blood loss and length of hospital stay. Duration of surgery was significantly longer in patients undergoing dual-loop reconstruction.

Conclusion

Dual-loop (Roux-en-Y) reconstruction with isolated pancreaticojejunostomy after partial pancreaticoduodenectomy is not superior to single-loop reconstruction regarding pancreatic fistula rate or other relevant outcomes. Additional superiority trials are therefore not warranted, although a high-quality trial may be justified to prove equivalence or non-inferiority.

[Capabilities of computed tomography to evaluate polymorphic changes in destructive pancreatitis]

OBJECTIVE

To determine whether the lower-density pancreatic parenchymal areas detected by a computed tomography (CT) study in patients with acute pancreatitis correspond to the necrotic portions of the gland or whether these changes may be reversal.

MATERIAL AND METHODS

The investigation covered 25 patients who had undergone or dynamic CT studies made at different time intervals. Two independent investigators with 4 and 19 years of experience retrospectively analyzed the results of both CT studies. Target estimation was made of the extent (volume) of and CT density changes in the hypodense areas of the gland parenchyma.

RESULTS

Seven (28%) of the 25 patients were noted to have higher CT density in the areas that had decreased density during primary CT studies (more than a 30 HU increase was rated as significant). There was a statistically significant difference between the patient groups when comparing the extent of hypodense areas and the difference in CT density (t-test, p = 0.006); Mann-Whitney U-test, p = 0.01 for extent difference and t-test, p = 0.00; Mann-Whitney U-test, p = 0.00 for CT density difference. There was also a correlation between the extent of hypodense areas and the difference in their CT density (Pearson: r = -0.533, p = 0.006; Spearman: r = -0.636, p = 0.001).

CONCLUSION

The results of our investigation may suggest that the lower-density pancreatic parenchymal areas cannot always correspond to necrotic changes and may be reversible.

Outcome of surgery for pancreatic neuroendocrine neoplasms

BACKGROUND

The incidence of pancreatic neuroendocrine neoplasms (pNEN) is increasing. This study aimed to evaluate predictors of overall survival and the indication for surgery.

METHODS

Data collected between October 2001 and December 2012 were analysed. Histological grading and staging was based on the classifications of the World Health Organization, the International Union Against Cancer and the European Neuroendocrine Tumour Society.

RESULTS

Some 310 patients (150 female, 48·4 per cent) underwent surgical resection. The final survival analysis included 291 patients. Five-year overall survival differed according to tumour grade (G): 91·0 per cent among 156 patients with pancreatic neuroendocrine tumours (pNET) G1, 70·8 per cent in 111 patients with pNET G2, and 20 per cent in 24 patients with pancreatic neuroendocrine carcinomas (pNEC) G3 (P < 0·001). Tumours graded G3 (hazard ratio (HR) 6·96, 95 per cent confidence interval 3·67 to 13·21), the presence of distant metastasis (HR 2·41, 1·32 to 4·42) and lymph node metastasis (HR 2·10, 1·07 to 4·16) were independent predictors of worse survival (P < 0·001, P = 0·004 and P = 0·032 respectively). Eight of 61 asymptomatic patients with pNEN smaller than 2 cm had tumours graded G2 or G3, and six of 51 patients had lymph node metastasis. Among patients with pNEC G3, the presence of distant metastasis had a significant impact on the 5-year overall survival rate: 0 per cent versus 43 per cent in those without distant metastasis (P = 0·036).

CONCLUSION

Neuroendocrine tumours graded G3, lymph node and distant metastasis are independent predictors of worse overall survival in patients with pNEN.

Diagnosis and treatment of autoimmune pancreatitis types 1 and 2

Background

Autoimmune pancreatitis (AIP) is characterized by diffuse or focal swelling of the pancreas. AIP has been divided into types 1 and 2. The aim of the study was to evaluate and compare the clinicopathological characteristics, therapy and outcome of patients with AIP.

Methods

The medical records of patients diagnosed with AIP between January 2003 and July 2011 were reviewed. Characteristics of patients with AIP types 1 and 2 were compared with those of patients with pancreatic ductal adenocarcinoma (PDAC).

Results

AIP was classified as type 1 in 40 patients and type 2 in 32 according to the HISORt (Histology, Imaging, Serology, Other organ involvement, Response to therapy) criteria. Patients with histologically confirmed AIP type 2 were younger than those with type 1 (P = 0·005). Some 30 of 32 patients with AIP type 2 were found to have a localized tumour-like pancreatic mass and underwent pancreatectomy, compared with only 16 of 40 with type 1 (P &lt; 0·001). Three of 25 patients with AIP type 2 presented with raised serum levels of IgG4 compared with 21 of 38 with type 1 (P &lt; 0·001). There was no difference in symptoms and involvement of other organs between AIP types 1 and 2. Presentation with weight loss was more common among patients with PDAC than those with AIP, but there was no difference in pain or jaundice between the groups. Raised serum carbohydrate antigen 19-9 levels were more prevalent in patients with PDAC.

Conclusion

Patients with AIP type 2 frequently present with abdominal pain and a tumour-like mass. Differentiating AIP from PDAC is difficult, so making the clinical decision regarding operative versus conservative management is challenging.

[Developments in pancreatic surgery during the past ten years]

Pancreatic surgery has undergone significant progress during recent years. Specialised centres with interdisciplinary expertise have led to improved patient care with decreased morbidity and mortality. Regarding evidence-based medicine, consensus definitions on morbidity as well as high-quality studies, systematic reviews and meta-analyses on different topics of pancreatic surgery have been published. In acute pancreatitis paradigms have shifted towards conservative management, in chronic pancreatitis parenchyma-sparing resection techniques have widely become accepted. Management of cystic lesions - especially intraductal papillary mucinous neoplasms (IPMN) - has attracted great interest in surgical practice. In pancreatic cancer treatment not only surgical resection techniques have improved but also the central impact of adjuvant treatment has been demonstrated in large multicentre trials.