Comparing American Gastroenterological Association Pancreatic Cyst Management Guidelines with Fukuoka Consensus Guidelines as Predictors of Advanced Neoplasia in Patients with Suspected Pancreatic Cystic Neoplasms

Diagnostics and Management of Pancreatic Cystic Lesions-New Techniques and Guidelines

Pancreatic cystic lesions (PCLs) are increasingly diagnosed owing to the wide use of cross-sectional imaging techniques. Accurate identification of PCL categories is critical for determining the indications for surgical intervention or surveillance. The classification and management of PCLs rely on a comprehensive and interdisciplinary evaluation, integrating clinical data, imaging findings, and cyst fluid markers. EUS (endoscopic ultrasound) has become the widely used diagnostic tool for the differentiation of pancreatic cystic lesions, offering detailed evaluation of even small pancreatic lesions with high sensitivity and specificity. Additionally, endoscopic ultrasound-fine-needle aspiration enhances diagnostic capabilities through cytological analysis and the assessment of fluid viscosity, tumor glycoprotein concentration, amylase levels, and molecular scrutiny. These detailed insights play a pivotal role in improving the clinical prognosis and management of pancreatic neoplasms. This review will focus mainly on the latest recommendations for the differentiation, management, and treatment of pancreatic cystic lesions, highlighting their clinical significance.

The multidisciplinary pancreatic cyst clinic: A collaborative approach to streamlined management

BACKGROUND

Pancreatic cysts are often incidentally detected on routine imaging studies. Of these, mucinous cysts have a malignant potential. Several guidelines propose different management strategies, and implementation in patient care is inconsistent in the absence of dedicated infrastructure.

METHODS

To address the challenges of pancreatic cyst diagnosis and management, we established a multidisciplinary pancreas cyst clinic (PCC) within our health system. This clinic encompasses both tertiary care academic centers and community hospitals, with leadership from surgical oncology, gastroenterology, and radiology. Our PCC's primary goal is to provide accurate diagnosis and tailored management recommendations for all patients with pancreatic cysts. Additionally, we maintain a prospective database to study the disease's natural history and the outcomes of various treatment strategies.

CLINIC INFRASTRUCTURE

The clinic meets once per week for 45 min virtually via Zoom in the mornings. Patients are referred via electronic medical record (EMR) order, telephone call, or email from patient or referring provider. A dedicated advanced practice provider reviews referrals several times per day, calls patients to gather clinical data, ensures imaging is uploaded, and coordinates logistical aspects of the meeting during the dedicated time. Conferences are attended by representatives from surgery, radiology, medical pancreatology, and interventional gastroenterology. Each patient case is reviewed in detail and recommendations are submitted to referring providers and patients via an EMR message and letter. For patients requiring imaging surveillance, patients are followed longitudinally by the referring provider, gastroenterology team, or surgical team. For patients requiring endoscopic ultrasound (EUS) or surgical consultation, expedited referral to these services is made with prompt subsequent evaluation.

RESULTS

A total of 1052 patients from our health system were evaluated between 2020 and 2021. Of these, 196 (18.6 %) underwent EUS, 41 (3.9 %) underwent upfront surgical resection, and the remainder were referred to gastroenterology (141-13.4 %), surgery (314-29.8 %), or back to their referring provider (597-56.7 %) for ongoing surveillance in collaboration with their primary care provider (PCP). Of cysts under surveillance, 61.3 % remained stable, 13.2 % increased in size, and 2 % decreased in size. A total of 2.3 % of patients were recommended to discontinue surveillance.

CONCLUSIONS

The PCC provides infrastructure that has served to provide multidisciplinary review and consensus recommendations to patients with pancreatic cysts. This has served to improve the application of guidelines while providing individualized recommendations to each patient, while aiding non-expert referring providers throughout the region.

Novel Insights into Postoperative Surveillance in Resected Pancreatic Cystic Neoplasms-A Review

Pancreatic cystic lesions (PCL) are frequently encountered in clinical practice and some are referred to surgery due to their neoplastic risk or malignant transformation. The management of PCL involves complex decision-making, with postoperative surveillance being a key component for long-term outcomes, due to the potential for recurrence and postoperative morbidity. Unfortunately, the follow-up of resected patients is far from being optimal and there is a lack of consensus on recommendations with regard to timing and methods of surveillance. Here, we summarize the current knowledge on the postoperative surveillance of neoplastic pancreatic cysts, focusing on the mechanisms and risk factors for recurrence, the recurrence rates according to the initial indication for surgery, the final result of the surgical specimen and neoplastic risk in the remaining pancreas, as well as the postsurgical morbidity comprising pancreatic exocrine insufficiency, metabolic dysfunction and diabetes after resection, according to the type of surgery performed. We analyze postsurgical recurrence rates and morbidity profiles, as influenced by different surgical techniques, to better delineate at-risk patients, and highlight the need for tailored surveillance strategies adapted to preoperative and operative factors with an impact on outcomes.

Pancreatic Cyst Fluid Analysis

Pancreatic cyst fluid analysis can help diagnose pancreatic cyst type and the risk of high-grade dysplasia and cancer. Recent evidence from molecular analysis of cyst fluid has revolutionized the field with multiple markers showing promise in accurate diagnosis and prognostication of pancreatic cysts. The availability of multi-analyte panels has great potential for more accurate prediction of cancer.

Preoperative Predictive Features of Invasive Carcinoma Among Intraductal Papillary Mucinous Neoplasm of the Pancreas

OBJECTIVE

Noninvasive intraductal papillary mucinous neoplasms (IPMNs) theoretically do not metastasize. The purpose of this study is to preoperatively distinguish invasive carcinomas associated with IPMN from noninvasive IPMN.

METHODS

A total of 131 patients who underwent surgical resection for IPMN were retrospectively analyzed to identify the predictors of invasive carcinoma, based on the International Association of Pancreatology Consensus Guidelines.

RESULTS

Of the 131 patients, 29 (22%) had invasive carcinomas and 102 (78%) had noninvasive IPMN. An enhancing mural nodule (MN) greater than or equal to 5 mm, obstructive jaundice, an abrupt change in the caliber of the pancreatic duct (PD) with distal pancreatic atrophy, and lymphadenopathy were the significant predictors of invasive carcinoma in univariate analysis. The optimal cutoff value for the size of the enhancing MN to differentiate invasive carcinoma was 13 mm. In multivariate analysis, enhancing MN greater than or equal to 13 mm, obstructive jaundice, and an abrupt change in the PD caliber were the independent predictors. When all these factors were absent, only 17% were invasive carcinomas.

CONCLUSIONS

Enhancing MN greater than or equal to 13 mm, obstructive jaundice, and an abrupt change in the PD caliber were predictive factors for invasive carcinoma. Systematic lymph node dissection may be omitted when a high-risk patient has none of these factors.

Multi-institutional Validation Study of Cyst Fluid Protein Biomarkers in Patients With Cystic Lesions of the Pancreas

OBJECTIVE

Prospective evaluation of 2 clinical-molecular models in patients with unknown pathology who underwent endoscopic ultrasound with fine-needle aspiration (EUS-FNA) for a cystic lesion of the pancreas.

SUMMARY OF BACKGROUND DATA

Preoperative prediction of histologic subtype (mucinous vs nonmucinous) and grade of dysplasia in patients with pancreatic cystic neoplasms is challenging. Our group has previously published 2 clinical-molecular nomograms for intraductal papillary mucinous neoplasms (IPMN) that incorporated both clinical/radiographic features and cyst fluid protein markers (sFASL, CA72-4, MMP9, IL-4).

METHODS

This multiinstitutional study enrolled patients who underwent EUS-FNA for a cystic lesion of the pancreas. Treatment recommendations regarding resection were based on standard clinical, radiographic, and endoscopic features. Predicted probabilities of high-risk IPMN (high-grade dysplasia/invasive cancer) were calculated using the previously developed clinical-molecular nomograms.

RESULTS

Cyst fluid was obtained from 100 patients who underwent diagnostic EUS-FNA. Within this group there were 35 patients who underwent resection, and 65 were monitored radiographically. Within the group that underwent resection, 26 had low-risk IPMN or benign non-IPMN lesions, and 9 had high-risk IPMN. Within the surveillance group, no patient progressed to resection or developed cancer after a median follow-up of 12 months (range: 0.5-38). Using the clinical/radiographic nomogram alone, 2 out of 9 patients with high-risk IPMN had a predicted probability >0.5. In the clinical-molecular models, 6 of 9 patients in model 1, and 6 of 9 in model 2, had scores >0.5.

CONCLUSIONS

This prospective study of patients with unknown cyst pathology further demonstrates the importance of cyst fluid protein analysis in the preoperative identification of patients with high-risk IPMN. Longer follow-up is necessary to determine if this model will be useful in clinical practice.

Pancreatic cystic neoplasms: a review of current recommendations for surveillance and management

Pancreatic cystic neoplasms (PCN) comprise of a diverse array of pancreatic cysts, including intraductal papillary mucinous neoplasms (IPMN), mucinous cystic neoplasms (MCN), serous cystic neoplasms (SCN), cystic neuroendocrine tumors (cNET), and many others. Increasing use of cross-sectional imaging has resulted in greater numbers of PCNs discovered incidentally. The overall risk of malignancy is low, but can vary considerably between different classes of PCNs. Furthermore, many pancreatic cysts are indeterminate on imaging, and the inability to reliably predict the course of disease remains a challenge for radiologists. Due to the variability in disease course and a lack of high-quality studies on PCNs, there is no universal consensus when it comes to balancing optimal surveillance while avoiding the risk for overtreatment. Currently, there are three widely accepted international guidelines outlining guidelines for surveillance and management of PCNs: the American Gastroenterological Association (AGA) in 2015, the International Association of Pancreatology (IAP) last revised in 2017, and the European Study Group on Cystic Tumours of the Pancreas (European) last revised in 2018. In 2017, the American College of Radiology released its own comprehensive set of recommendations for managing indeterminate pancreatic cysts that are detected incidentally on CT or MRI. The purpose of this paper is to describe the key differences between the ACR recommendations and the aforementioned three sets of guidelines regarding cyst management, imaging surveillance, performance, and cost-effectiveness.

Evaluating the accuracy of three international guidelines in identifying the risk of malignancy in pancreatic cysts: a retrospective analysis of a surgical treated population

BACKGROUND AND STUDY AIMS

The international consensus Fukuoka guideline (Fukuoka ICG), The European evidence-based guideline on pancreatic cystic neoplasms (European EBG) and the American Gastroenterological Association institute guideline on the diagnosis and management of asymptomatic neoplastic pancreatic cysts (AGA IG) are 3 frequently cited guidelines for the risk stratification of neoplastic pancreatic cysts. The aim of this study was to assess the accuracy of detecting malignant cysts by strictly applying these guidelines retrospectively to a cohort of surgically resected pancreatic cysts.

PATIENTS AND METHODS

72 resected cysts were included in the analysis. Invasive carcinoma, high grade dysplasia and neuro-endocrine tumour were considered as "malignant cysts" for the purpose of the study.

RESULTS

32% of the resected cysts were malignant. The analysis showed that the Fukuoka ICG, European EBG and AGA IG had a sensitivity of 66,8%, 95,5%, 80%; a specificity of 26,8%, 11,3%, 43,8%; a positive predictive value of 31,8%, 35%, 47,1% and a negative predicted value of 61,1%, 83,3%, 77,8% respectively. The missed malignancy rate was respectively 11,3%, 1,5%, 7,7% and surgical overtreatment was respectively 48,4%, 59,1%, 34,6%.

CONCLUSION

In this retrospective analysis, the European EBG had the lowest rate of missed malignancy at the expense of a high number of "unnecessary" resections. The Fukuoka ICG had the highest number of missed malignancy. The AGA IG showed the lowest rate of unnecessary surgery at the cost of a high number of missed malignancy. There is need to develop better biomarkers to predict the risk of malignancy.

High-Risk Characteristics Associated with Advanced Pancreatic Cystic Lesions: Results from a Retrospective Surgical Cohort

BACKGROUND AND AIM

The management of pancreatic cystic lesions (PCLs) remains controversial. We performed a retrospective study to determine characteristics associated with advanced PCLs (A-PCLs) and whether these characteristics vary in different pathological types of PCLs. The additional diagnostic value of endoscopic ultrasound (EUS) was also evaluated.

METHODS

Patients who underwent surgical resection for an identified PCLs by imaging modalities were included. A logistic regression model was developed to identify significant characteristics for A-PCLs. EUS data was assessed separately.

RESULTS

Three hundred and fifty-three patients were included, and 125 patients (35.4%) were A-PCLs. The presence of main pancreatic duct (MPD) diameter ≥ 10 mm (odds ratio [OR], 11.7; 95% confidence interval [CI], 1.53-89.2; P = 0.018), mural nodules ≥ 5 mm (OR, 11.67; 95% CI, 2.3-59.05; P = 0.003), solid components within cysts (OR, 30.87; 95% CI, 7.23-131.7; P < 0.0001) and high serum CA19-9 levels (OR, 1.006; 95% CI, 1.001-1.011; P = 0.02) were independently associated with the presence of A-PCLs. The presence of septa was independently associated with the presence of non-A-PCLs (OR, 0.147; 95% CI, 0.04-0.6; P = 0.008). Males who had a history of tobacco abuse (P < 0.0001) and had a greatly dilated MPD (P < 0.0001) were more common in advanced intraductal papillary mucinous neoplasms (IPMC) patients. Solid pseudopapillary neoplasm (SPT) often occurred in young women (P < 0.0001), mostly asymptomatically (P < 0.0001) and with lower serum CA19-9 levels (P < 0.0001). In the 124 patients who underwent EUS-guided fine-needle aspiration (EUS-FNA), five additional characteristics (4 mural nodules and 1 MPD involvement) were identified by EUS imaging and 17 patients were identified with abnormal cytological results (13 atypical cells and 4 suspicious for malignancy cells) by EUS-FNA.

CONCLUSION

On the basis of a retrospective study with large sample size, the presence of MPD ≥ 10 mm, mural nodules, solid components, and high serum CA19-9 levels were independently associated with the presence of A-PCLs. The high-risk characteristics may vary across different types of A-PCLs. EUS and EUS-FNA could provide additional diagnostic information for PCLs.

Resection of pancreatic cystic neoplasms in recurrent acute pancreatitis prevents recurrent pancreatitis but does not identify more malignancies

BACKGROUND

Recurrent acute pancreatitis (RAP) may be a presenting feature of and an indication for resection of pancreatic cysts, including intra-ductal papillary mucinous neoplasm (IPMN). Few data are available regarding the prevalence of malignancy and post-operative RAP in this population.

AIM

To study the role of resection to help prevent RAP and analyze if presentation as RAP would be a predictor for malignancy.

METHODS

This retrospective study assessed 172 patients who underwent surgical resection of pancreatic cystic neoplasms at a university hospital between 2002 and 2016. The prevalence of preoperative high-risk cyst features, and of neoplasia was compared between patients with and without RAP. To identify the cause of pancreatitis, all the patients had a detailed history of alcohol, smoking, medications obtained, and had cross-sectional imaging (contrast-enhanced computed tomography/magnetic resonance imaging) and endoscopic ultrasound to look for gallstone etiology and other structural causes for pancreatitis. The incidence of RAP post-resection was the primary outcome.

RESULTS

IPMN accounted for 101 cases (58.7%) {[branch duct (BD) 59 (34.3%), main duct (MD) 42] (24.4%)}. Twenty-nine (16.9%) presented with RAP (mean 2.2 episodes): 15 had BD-IPMN, 8 MD-IPMN, 5 mucinous cystic neoplasm and 1 serous cystic neoplasm. Malignancy was similar among those with vs without RAP for all patients [6/29 (20.7%) vs 24/143 (16.8%)] and IPMN patients [6/23 (26.1%) vs 23/78 (29.5%)], although tended to be higher with RAP in BD-IPMN, [5/15 (33.3%) vs 3/44 (6.8%), P = 0.04]. At mean follow-up of 7.2 years, 1 (3.4%) RAP patient had post-resection RAP. The mean episodes of acute pancreatitis before vs after surgery were 3.4 vs 0.02 (P < 0.0001).

CONCLUSION

Malignancy was not increased in patients with pancreatic cystic neoplasms who have RAP compared to those without RAP. In addition, specific cyst charac-teristics were not clearly associated with RAP. The incidence of RAP was markedly decreased in almost all patients following cyst resection.

Use of Artificial Intelligence Deep Learning to Determine the Malignant Potential of Pancreatic Cystic Neoplasms With Preoperative Computed Tomography Imaging

BACKGROUND

Society consensus guidelines are commonly used to guide management of pancreatic cystic neoplasms (PCNs). However, downsides of these guidelines include unnecessary surgery and missed malignancy. The aim of this study was to use computed tomography (CT)-guided deep learning techniques to predict malignancy of PCNs.

MATERIALS AND METHODS

Patients with PCNs who underwent resection were retrospectively reviewed. Axial images of the mucinous cystic neoplasms were collected and based on final pathology were assigned a binary outcome of advanced neoplasia or benign. Advanced neoplasia was defined as adenocarcinoma or intraductal papillary mucinous neoplasm with high-grade dysplasia. A convolutional neural network (CNN) deep learning model was trained on 66% of images, and this trained model was used to test 33% of images. Predictions from the deep learning model were compared to Fukuoka guidelines.

RESULTS

Twenty-seven patients met the inclusion criteria, with 18 used for training and 9 for model testing. The trained deep learning model correctly predicted 3 of 3 malignant lesions and 5 of 6 benign lesions. Fukuoka guidelines correctly classified 2 of 3 malignant lesions as high risk and 4 of 6 benign lesions as worrisome. Following deep learning model predictions would have avoided 1 missed malignancy and 1 unnecessary operation.

DISCUSSION

In this pilot study, a deep learning model correctly classified 8 of 9 PCNs and performed better than consensus guidelines. Deep learning can be used to predict malignancy of PCNs; however, further model improvements are necessary before clinical use.

Cost-effectiveness of consensus guideline based management of pancreatic cysts: The sensitivity and specificity required for guidelines to be cost-effective

BACKGROUND

Detection of cystic lesions of the pancreas has outpaced our ability to stratify low-grade cystic lesions from those at greater risk for pancreatic cancer, raising a concern for overtreatment.

METHODS

We developed a Markov decision model to determine the cost-effectiveness of guideline-based management for asymptomatic pancreatic cysts. Incremental costs per quality-adjusted life year gained and survival were calculated for current management guidelines. A sensitivity analysis estimated the effect on cost-effectiveness and mortality if overtreatment of low-grade cysts is avoided, and the sensitivity and specificity thresholds required of methods of cyst stratification to improve costs expended.

RESULTS

"Surveillance" using current management guidelines had an incremental cost-effectiveness ratio of $171,143/quality adjusted life year compared with no surveillance or operative treatment ("do nothing"). An incremental cost-effectiveness ratio for surveillance decreases to $80,707/quality adjusted life year if the operative overtreatment of low-grade cysts was avoided. Assuming a societal willingness-to-pay of $100,000/quality adjusted life year, the diagnostic specificity for high-risk cysts must be >67% for surveillance to be preferred over surgery and "do nothing." Changes in sensitivity alone cannot make surveillance cost-effective. Most importantly, survival in surveillance is worse than "do nothing" for 3 years after cyst diagnosis, although long-term survival is improved. The disadvantage is eliminated when overtreatment of low-grade cysts is avoided.

CONCLUSION

Current management of pancreatic cystic lesions is not cost-effective and may increase mortality owing to overtreatment of low-grade cysts. The specificity for risk stratification for high-risk cysts must be greater than 67% to make surveillance cost-effective.

Comparing the clinical impact of pancreatic cyst surveillance programs: A trial of the ECOG-ACRIN cancer research group (EA2185)

BACKGROUND

The optimal surveillance strategy for pancreatic cysts, which occur in up to 20% of the adult population, is ill defined. The risk of malignant degeneration of these cysts is low, however the morbidity and mortality associated with pancreatic cancer are high. Two clinical surveillance guidelines are in regular use. Both the Fukuoka and American Gastroenterological Association (AGA) guidelines rely on radiographic and endoscopic imaging. They differ primarily in their recommended frequencies of interval surveillance imaging. While evidence driven clinical guidelines should promote higher quality care, competing guidelines on the same topic may provide discordant recommendations and potential reduction in the quality and/or value of care.

OBJECTIVES

The primary objective is to compare the clinical effectiveness of the two surveillance guidelines to identify patients most likely to benefit from pancreatic resection. Secondary objectives include comparison of resource utilization, patient reported outcomes, incidental findings are other clinical outcomes.

METHODS

4606 asymptomatic patients with newly identified pancreatic cysts ≥1 cm in diameter will be randomized 1:1 to high intensity (Fukuoka) or low intensity (AGA) surveillance. All participants will be followed prospectively for 5 years.

CONCLUSION

Differing guidelines confuse providers, patients and policymakers. This large, prospective, randomized trial will compare the clinical effectiveness and resource allocation requirements of two guidelines addressing a common clinical entity. CLINICALTRIALS.

GOV IDENTIFIER

NCT04239573.

Importance of each high-risk stigmata and worrisome features as a predictor of high-grade dysplasia in intraductal papillary mucinous neoplasms of the pancreas

BACKGROUND

High-risk stigmata (HRS) and 'worrisome features' (WFs) are defined as predictive factors for malignancies of intraductal papillary mucinous neoplasms (IPMNs). We performed this study to determine the importance and odds ratio (OR) of each HRS and WFs as predictors for high-grade dysplasia (HGD).

METHODS

We analyzed 295 patients who underwent pancreatectomy for branch duct and mixed-type IPMN, and evaluated the association between HRS and WFs (as defined by the '2017 Fukuoka Consensus Guidelines') and HGD.

RESULTS

The proportions of patients with low-grade dysplasia (LGD), HGD, and invasive carcinoma were 47%, 28%, and 25%, respectively. Multivariate analysis comparing patients with LGD and HGD using all HRS and WFs revealed that an enhancing mural nodule ≥5 mm (OR: 4.1), pancreatitis (OR: 2.2), and thickened/enhancing cyst walls (OR: 2.2) were independent predictive factors for HGD. Based on the OR (the former factor is two points and the latter two factors are each one point), the incidence of HGD in patients with none (n = 43), one (n = 82), two (n = 25), three (n = 52), and four (n = 19) of these predictive factors were 9%, 26%, 52%, 62%, and 63%, respectively. Assuming a score of one or higher as a surgical indication, the sensitivity, specificity, positive predict value, and negative predict value of HGD were 95, 38, 44, and 91%.

CONCLUSIONS

Our derived scoring system using more important factors in HRS and WFs may be useful for predicting HGD and determining surgical indications of IPMN.

Molecular Diagnosis of Cystic Neoplasms of the Pancreas: a Review

BACKGROUND

The prevalence of incidental pancreatic cystic neoplasms (PCNs) has increased dramatically with advancements in cross-sectional imaging. Diagnostic imaging is limited in differentiating between benign and malignant PCNs. The aim of this review is to provide an overview of biomarkers that can be used to distinguish PCNs.

METHODS

A review of the literature on molecular diagnosis of cystic neoplasms of the pancreas was performed.

RESULTS

Pancreatic cysts can be categorized into inflammatory and non-inflammatory lesions. Inflammatory cysts include pancreatic pseudocysts. Noninflammatory lesions include both mucinous and non-mucinous lesions. Mucinous lesions include intraductal papillary mucinous neoplasm (IPMN) and mucinous cystic neoplasm. Non-mucinous lesions include serous cystadenoma and solid-pseudopapillary tumor of the pancreas. Imaging, cyst aspiration, and histologic findings, as well as carcinoembryonic antigen and amylase are commonly used to distinguish between cyst types. However, molecular techniques to detect differences in genetic mutations, protein expression, glycoproteomics, and metabolomic profiling are important developments in distinguishing between cyst types.

DISCUSSION

Nomograms incorporating common clinical, laboratory, and imaging findings have been developed in a better effort to predict malignant IPMN. The incorporation of top molecular biomarker candidates to nomograms may improve the predictive ability of current models to more accurately diagnose malignant PCNs.

Pancreatic mucinous cystic neoplasms: a clinicopathological study of 11 cases and detailed review of literature

Background

Mucinous cystic neoplasms (MCNs) of pancreas are relatively rare, occur almost exclusively in middle-aged females, and are overwhelmingly located in the body and tail of the pancreas, histologically show an ovarian type stroma. MCNs are premalignant, low aggressive tumors. Here we describe the clinicopathologic and radiologic features and follow up of cases diagnosed in our practice. We also present a detailed review of recent literature.

Materials and methods

Based on strict criteria, 11 cases diagnosed between 2002 and 2016 were included in the study.

Results

All cases were reviewed histologically. Mean and median age was 46.7 and 46 years respectively. All patients were females and 9 out of 11 cases were located in the body and/or tail of the pancreas. Mean tumor size was 8 cm. Grossly, cysts were uni or multilocular and ranged from a few millimeters to several centimeters in diameter. Microscopically, all cases showed characteristic tall columnar, mucin producing epithelium and ovarian type stroma. Atypia was mild in 8 cases and severe in 3 cases. The latter 3 cases were classified as non-invasive MCNs with high grade dysplasia (2 cases) and MCN with an associated invasive carcinoma (1 case). On immunohistochemistry, all cases showed epithelial positivity for cytokeratin AE1/AE3 and stromal positivity for vimentin and smooth muscle actin. Follow up was available in 7 cases. All patients were alive and well with no recurrence.

Conclusions

Our cases show features similar to those described in other published studies although cases in our series tended to be larger in number. Since these tumors are relatively rare, premalignant and have strict diagnostic criteria, they must always be considered in the differential diagnosis of pancreatic mucinous cystic lesions. Larger studies incorporating greater number of patients and more detailed follow up will help in increasing our understanding of MCNs.

Pancreatic Cysts in the Elderly

PURPOSE OF REVIEW

Incidental pancreatic cysts are common, and management strategies continue to evolve. This review summarizes diagnostic and management recommendations in older patients with these lesions based on guidelines and best clinical evidence.

RECENT FINDINGS

Diagnosis of cyst type has been enhanced with improved imaging and cyst fluid analysis and visualization. Recent outcome studies indicate that certain cyst types should be followed independent of patient age as long as certain criteria which are reviewed are met. Differentiation of pancreatic cyst type is important as this dictates the need for long-term follow-up. Because most cyst-related neoplasia occurs in older patients, surveillance should continue within certain guidelines.

Accuracy of Fukuoka and American Gastroenterological Association Guidelines for Predicting Advanced Neoplasia in Pancreatic Cyst Neoplasm: A Meta-Analysis

BACKGROUND

A differential diagnosis of advanced pancreatic cystic neoplasms (PCNs) is critical to determine optimal treatment. The Fukuoka and American Gastroenterological Association (AGA) guidelines are the most widely accepted criteria for the management of PCNs.

OBJECTIVE

This study aimed to evaluate the diagnostic value of these guidelines in predicting advanced neoplasia (AN).

METHODS

A comprehensive electronic search of the PubMed, EMBASE, Web of Science, Cochrane Library, and Scopus databases was conducted to identify all relevant studies evaluating the Fukuoka and AGA guidelines in surgically resected and histologically confirmed PCNs. Pooled sensitivity, specificity, and diagnostic odds ratios (DORs) were calculated as compound measures of diagnostic accuracy using the random-effects model. Summary of receiver operating characteristic (SROC) curves and the area under the curve (AUC) were also performed.

RESULTS

A total of 21 studies with 3723 patients were included in this meta-analysis. Of these studies, 15, 4, and 2 evaluated the Fukuoka guidelines, the AGA guidelines, and both guidelines, respectively. For AN prediction, the Fukuoka guidelines had a pooled sensitivity of 0.67 (95% confidence interval [CI] 0.64-0.70), pooled specificity of 0.64 (95% CI 0.62-0.66), and pooled DOR of 6.28 (95% CI 4.38-9.01), with an AUC of the SROC of 0.78. AGA guidelines showed a pooled sensitivity of 0.59 (95% CI 0.52-0.65), pooled specificity of 0.77 (95% CI 0.74-0.80), and pooled DOR of 5.84 (95% CI 2.60-13.15), with an AUC of 0.79 (95% CI 0.70-0.88).

CONCLUSION

When used alone, the Fukuoka and AGA guidelines showed similar but unsatisfactory diagnostic accuracy in the risk stratification of malignant potential of PCN. Thus, we recommend that they be applied only as a broad framework in clinical practice.

Cross Validation of the Monoclonal Antibody Das-1 in Identification of High-Risk Mucinous Pancreatic Cystic Lesions

BACKGROUND & AIMS

Although pancreatic cystic lesions (PCLs) are frequently and incidentally detected, it is a challenge to determine their risk of malignancy. In immunohistochemical and enzyme-linked immunosorbent assay (ELISA) analyses of tissue and cyst fluid from pancreatic intraductal papillary mucinous neoplasms, the monoclonal antibody Das-1 identifies those at risk for malignancy with high levels of specificity and sensitivity. We aimed to validate the ability of Das-1 to identify high-risk PCLs in comparison to clinical guidelines and clinical features, using samples from a multicenter cohort.

METHODS

We obtained cyst fluid samples of 169 PCLs (90 intraductal papillary mucinous neoplasms, 43 mucinous cystic neoplasms, and 36 non-mucinous cysts) from patients undergoing surgery at 4 tertiary referral centers (January 2010 through June 2017). Histology findings from surgical samples, analyzed independently and centrally re-reviewed in a blinded manner, were used as the reference standard. High-risk PCLs were those with invasive carcinomas, high-grade dysplasia, or intestinal-type intraductal papillary mucinous neoplasms with intermediate-grade dysplasia. An ELISA with Das-1 was performed in parallel using banked cyst fluid samples. We evaluated the biomarker's performance, generated area under the curve values, and conducted multivariate logistic regression using clinical and pathology features.

RESULTS

The ELISA for Das-1 identified high-risk PCLs with 88% sensitivity, 99% specificity, and 95% accuracy, at a cutoff optical density value of 0.104. In 10-fold cross-validation analysis with 100 replications, Das-1 identified high-risk PCLs with 88% sensitivity and 98% specificity. The Sendai, Fukuoka, and American Gastroenterological Association guideline criteria identified high-risk PCLs with 46%, 52%, and 74% accuracy (P for comparison to Das-1 ELISA <.001). When we controlled for Das-1 in multivariate regression, main pancreatic duct dilation >5 mm (odds ratio, 14.98; 95% confidence interval, 2.63-108; P < .0012), main pancreatic duct dilation ≥1 cm (odds ratio, 47.9; 95% confidence interval, 6.39-490; P < .0001), and jaundice (odds ratio, 6.16; 95% confidence interval, 1.08-36.7; P = .0397) were significantly associated with high-risk PCLs.

CONCLUSIONS

We validated the ability of an ELISA with the monoclonal antibody Das-1 to detect PCLs at risk for malignancy with high levels of sensitivity and specificity. This biomarker might be used in conjunction with clinical guidelines to identify patients at risk for malignancy.

Overview and comparison of guidelines for management of pancreatic cystic neoplasms

Pancreatic cysts are identified at an increasing frequency. Although mucinous cystic neoplasms represent a pre-malignant condition, the majority of these lesions do not progress to cancer. Over the last 10 years several societies have established guidelines for the diagnosis, initial evaluation and surveillance of these lesions. Here we provide an overview of five commonly used guidelines: 2015 American Gastroenterological Association, 2017 International Association of Pancreatology, American College of Gastroenterology 2018, European Study Group and American College of Radiology. We describe the similarities and differences between the methods used to formulate these guidelines, the population they target and their approaches towards initial evaluation and surveillance of cystic lesions.

Glycopatterns and Glycoproteins Changes in MCN and SCN: A Prospective Cohort Study

Background. Advances in imaging improve the detection of malignant pancreatic cystic including mucinous cystic neoplasm (MCN), intraductal papillary mucinous neoplasm (IPMN), and mucinous cystic adenocarcinoma (MCA), but the distinction between benign and malignant lesions remains a problem. In an effort to establish glycopatterns as potential biomarkers for differential diagnosis between MCN and SCN, we systematically investigated the alterations of glycopatterns in cystic fluids for both SCN and MCN. Methods. Among the 75 patients enrolled, 37 were diagnosed as MCN and 38 as SCN based on histology. Lectin microarray analysis was performed on each sample, and the fluorescence intensity was used to obtain the fold-change. Then, mixed cyst fluids of MCN group and SCN group were cross bonded with magnetic particles coupled by Lectin STL and WGA, respectively. Hydrophilic interaction liquid chromatography (HILIC) enrichment was performed, liquid chromatography (LC)/mass spectrometry (MS) analysis and bioinformatical analysis was conducted to find the differential glycoproteins between MCNs and SCNs. Results. Through analysis of lectin microarray between MCNs and SCNs, stronger lectin signal patterns were assigned to Lectin WFA, DBA, STL, WGA, and BPL; and weaker signal patterns were assigned to Lectin PTL-I, Con A, ACA, and MAL-I. The glycoproteins were enriched by STL or WGA-coupled magnetic particles. Furthermore, the 10 identified correspondding genes were found to be significantly elevated in the mucinous cystadenoma: CLU, A2M, FGA, FGB, FGG, PLG, SERPINA1, SERPING1, C5, C8A, and C9. Bioinformatics analysis revealed that the above genes may activate the KEGG pathway: immune complement system. Conclusion. This study shows changes in glycopatterns and glycoproteins are associated with MCNs and SCNs.

Neutrophil-to-Lymphocyte Ratio as a Predictor of Invasive Carcinoma in Patients With Intraductal Papillary Mucinous Neoplasms of the Pancreas

OBJECTIVES

Preoperative determination of the grade of dysplasia in intraductal papillary mucinous neoplasms (IPMNs) is necessary for optimal management. Previous data have suggested that serum neutrophil-to-lymphocyte ratio (NLR) can predict invasive disease in patients with IPMN.

METHODS

A prospectively maintained database was queried for consecutive patients who underwent resection of IPMN. Exclusion criteria included recent diagnosis of cancer, immunosuppression, and infection or jaundice within 1 month of operation. A complete blood count with differential within 30 days of operation was used to calculate NLR.

RESULTS

Within the study period, 446 patients underwent resection for IPMN, and 348 patients (78%) met the inclusion criteria. Low-grade dysplasia was present in 60 patients (17%), 137 patients (39%) had intermediate-grade dysplasia, 76 (22%) had high-grade dysplasia, and 75 (22%) had invasive carcinoma. A higher NLR was associated with invasive carcinoma as compared with noninvasive disease (3.00 vs 2.68, P = 0.039). There was no difference in NLR between patients with high-risk (invasive and high-grade) and low-risk (low-grade and intermediate-grade) lesions (2.80 vs 2.71, P > 0.95).

CONCLUSIONS

Neutrophil-to-lymphocyte ratio was significantly higher in patients with IPMN-associated invasive carcinoma as compared with patients with noninvasive disease; however, NLR was not helpful in differentiating between high- and low-grade lesions.

Deep Learning to Classify Intraductal Papillary Mucinous Neoplasms Using Magnetic Resonance Imaging

OBJECTIVE

This study aimed to evaluate a deep learning protocol to identify neoplasia in intraductal papillary mucinous neoplasia (IPMN) in comparison to current radiographic criteria.

METHODS

A computer-aided framework was designed using convolutional neural networks to classify IPMN. The protocol was applied to magnetic resonance images of the pancreas. Features of IPMN were classified according to American Gastroenterology Association guidelines, Fukuoka guidelines, and the new deep learning protocol. Sensitivity and specificity were calculated using surgically resected cystic lesions or healthy controls.

RESULTS

Of 139 cases, 58 (42%) were male; mean (standard deviation) age was 65.3 (11.9) years. Twenty-two percent had normal pancreas; 34%, low-grade dysplasia; 14%, high-grade dysplasia; and 29%, adenocarcinoma. The deep learning protocol sensitivity and specificity to detect dysplasia were 92% and 52%, respectively. Sensitivity and specificity to identify high-grade dysplasia or cancer were 75% and 78%, respectively. Diagnostic performance was similar to radiologic criteria. Areas under the receiver operating curves (95% confidence interval) were 0.76 (0.70-0.84) for American Gastroenterology Association, 0.77 (0.70-0.85) for Fukuoka, and 0.78 (0.71-0.85) for the deep learning protocol (P = 0.90).

CONCLUSIONS

The deep learning protocol showed accuracy comparable to current radiographic criteria. Computer-aided frameworks could be implemented as aids for radiologists to identify high-risk IPMN.

Cyst Fluid Biosignature to Predict Intraductal Papillary Mucinous Neoplasms of the Pancreas with High Malignant Potential

BACKGROUND

Current standard-of-care technologies, such as imaging and cyst fluid analysis, are unable to consistently distinguish intraductal papillary mucinous neoplasms (IPMNs) of the pancreas at high risk of pancreatic cancer from low-risk IPMNs. The objective was to create a single-platform assay to identify IPMNs that are at high risk for malignant progression.

STUDY DESIGN

Building on the Verona International Consensus Conference branch duct IPMN biomarker review, additional protein, cytokine, mucin, DNA, and microRNA cyst fluid targets were identified for creation of a quantitative polymerase chain reaction-based assay. This included messenger RNA markers: ERBB2, GNAS, interleukin 1β, KRAS, MUCs1, 2, 4, 5AC, 7, prostaglandin E2R, PTGER2, prostaglandin E synthase 2, prostaglandin E synthase 1, TP63; microRNA targets: miRs 101, 106b, 10a, 142, 155, 17, 18a, 21, 217, 24, 30a, 342, 532, 92a, and 99b; and GNAS and KRAS mutational analysis. A multi-institutional international collaborative contributed IPMN cyst fluid samples to validate this platform. Cyst fluid gene expression levels were normalized, z-transformed, and used in classification and regression analysis by a support vector machine training algorithm.

RESULTS

From cyst fluids of 59 IPMN patients, principal component analysis confirmed no institutional bias/clustering. Lasso (least absolute shrinkage and selection operator)-penalized logistic regression with binary classification and 5-fold cross-validation used area under the curve as the evaluation criterion to create the optimal signature to discriminate IPMNs as low risk (low/moderate dysplasia) or high risk (high-grade dysplasia/invasive cancer). The most predictive signature was achieved with interleukin 1β, MUC4, and prostaglandin E synthase 2 to accurately discriminate high-risk cysts from low-risk cysts with an area under the curve of up to 0.86 (p = 0.002).

CONCLUSIONS

We have identified a single-platform polymerase chain reaction-based assay of cyst fluid to accurately predict IPMNs with high malignant potential for additional studies.

Current Guideline Controversies in the Management of Pancreatic Cystic Neoplasms

Pancreatic cystic lesions are a common clinical entity. The majority are neoplastic and have the potential for malignant transformation. To assist with patient management, a number of clinical guidelines have been developed over the past decade. However, controversies exist in regards to the various guidelines and treatment strategies they offer. This article will review the various clinical guidelines for management of pancreatic cysts, describe the limitations of these guidelines, and present future directions for improvement in clinical decision making for patients diagnosed with a pancreatic cystic neoplasm.

Long-term follow-up of low-risk branch-duct IPMNs of the pancreas: is main pancreatic duct dilatation the most worrisome feature?

OBJECTIVES

The management of branch-duct IPMN remains controversial due to the relatively low rate of malignant degeneration and the uncertain predictive role of high-risk stigmata (HRS) and worrisome features (WFs) identified by the 2012 International Consensus Guidelines. Our aim was to evaluate the evolution of originally low-risk (Fukuoka-negative) BD-IPMNs during a long follow-up period in order to determine whether the appearance of any clinical or morphological variables may be independently associated with the development of malignancy over time.

METHODS

A prospectively collected database of all patients with BD-IPMN referring to our Institute between 2002 and 2016 was retrospectively analyzed. Univariate and multivariate analysis of association between changes during follow-up, including appearance of HRS/WFs, and development of malignancy (high-grade dysplasia/invasive carcinoma) was performed.

RESULTS

A total of 167 patients were selected for analysis, and seven developed malignant disease (4.2%). During a median follow-up time of 55 months, HRS appeared in only three cases but predicted malignancy with 100% specificity. Worrisome features, on the other hand, appeared in 44 patients (26.3%). Appearance of mural nodules and MPD dilatation >5 mm showed a significant association with malignancy in multivariate analysis (p = 0.004 and p = 0.001, respectively). MPD dilatation in particular proved to be the strongest independent risk factor for development of malignancy (OR = 24.5).

CONCLUSIONS

The risk of pancreatic malignancy in this population is low but definite. The presence of major WFs, and especially MPD dilatation, should prompt a tighter follow-up with EUS and a valid cytological analysis whenever feasible.

Managing Incidental Pancreatic Cysts

PURPOSE OF REVIEW

The goal of this review is to critically analyze the current literature regarding the management of incidental pancreatic cysts. Given their increased rates of detection due to the frequent use of cross-sectional imaging, correctly identifying the subset of high risk lesions that are appropriate for surgical resection is critical. However, the existing consensus and societal guidelines discussed in this review lack high quality data to create evidence-based recommendations, making achieving this important aim challenging.

RECENT FINDINGS

Several recent studies have focused on the natural history of pancreatic cysts and defining the role of endoscopic ultrasound, which remains unclear. EUS-guided diagnostic tools include molecular analysis of obtained fluid; EUS-guided FNA, FNB, and intracystic forceps biopsy of the cyst wall; and confocal endomicroscopy. While their precise role in diagnosing pancreatic cystic neoplasms remains to be defined, they represent promising innovations that may play a future role in cyst assessment and management. Large, long-term, prospective studies of incidentally identified pancreatic cysts are essential to fully understand their natural history and potential for neoplastic progression. Given the absence of such data at present, an individualized patient approach is recommended.

The value of systemic inflammatory markers in identifying malignancy in mucinous pancreatic cystic neoplasms

The treatment decision-making of mucinous pancreatic cystic neoplasm (PCN) has become a common clinical problem since the diagnostic accuracy of current tests in identifying malignancies in pancreatic cysts is limited. In this study, we aimed to validate the predictive value of systemic inflammatory factors in detecting malignant PCNs. Two hundred and forty-five patients with pathologically confirmed mucinous PCNs in a single Chinese institution were retrospectively analyzed. Receiver operating characteristic (ROC) curves were calculated to determine the optimal cut-off values and measure the diagnostic value. The results showed that neutrophil count (P = 0.009), lymphocyte count (P = 0.002), neutrophil-to-lymphocyte ratio (NLR, P < 0.001), platelet-to-lymphocyte ratio (PLR, P < 0.001) and lymphocyte-to-monocyte ratio (LMR, P < 0.001) were distributed differently among the various differentiation groups of PCN. The univariate analyses indicated that a neutrophil count ≥ 2.8 × 10⁹/L (P = 0.024), lymphocyte count ≤ 1.9 × 10⁹/L (P < 0.001), PLR ≥ 125 (P < 0.001), NLR ≥ 1.96 (P < 0.001), and LMR ≤ 4.29 (P < 0.001) were significantly associated with invasive carcinomas in PCN patients. In addition, the multivariate analyses demonstrated that PLR ≥ 125 and LMR ≤ 4.29 were independent predictors of invasive malignancies. The ROC curves exhibited the malignant detection utility of the independent factor-based predictive model with an area under the curve (AUC) of 0.858 (P < 0.001). In conclusion, systemic inflammatory markers provide a supportive and easily accessible tool for the preoperative diagnoses of malignant PCNs.

Editorial: Management of the Small Asymptomatic Pancreatic Cyst: Somehow Along the Way We Forgot About the Patient

The incidentally identified pancreatic cyst is an increasing burden for both physicians and patients alike. Although we recognize that most of these lesions are benign and may not progress, a subset of these lesions are premalignant, may have frank cancer, and may progress over time. Most occur in older patients who have associated comorbidity. Recent studies highlight neoplastic features of these cysts that when present may warrant surgery or close long-term follow-up; however, there has been little study on the natural history factoring in patient comorbidity and pancreatic cancer-free survival. This retrospective cohort study underscores the importance of patient comorbidity in our management algorithm, and these data should prompt subsequent guidelines to factor in such comorbidity.

Revisions of international consensus Fukuoka guidelines for the management of IPMN of the pancreas

The management of intraductal papillary mucinous neoplasm (IPMN) continues to evolve. In particular, the indications for resection of branch duct IPMN have changed from early resection to more deliberate observation as proposed by the international consensus guidelines of 2006 and 2012. Another guideline proposed by the American Gastroenterological Association in 2015 restricted indications for surgery more stringently and recommended physicians to stop surveillance if no significant change had occurred in a pancreatic cyst after five years of surveillance, or if a patient underwent resection and a non-malignant IPMN was found. Whether or not it is safe to do so, as well as the method and interval of surveillance, has generated substantial debate. Based on a consensus symposium held during the meeting of the International Association of Pancreatology in Sendai, Japan, in 2016, the working group has revised the guidelines regarding prediction of invasive carcinoma and high-grade dysplasia, surveillance, and postoperative follow-up of IPMN. As the working group did not recognize the need for major revisions of the guidelines, we made only minor revisions and added most recent articles where appropriate. The present guidelines include updated information and recommendations based on our current understanding, and highlight issues that remain controversial or where further research is required.

Pancreatic Cysts and Guidelines

Pancreatic cysts, especially incidental asymptomatic ones seen on noninvasive imaging such as CT or MR imaging, remain a clinical challenge. The etiology of such cysts may range from benign cysts without any malignant potential such as pancreatic pseudocysts and serous cystadenomas to premalignant or frankly malignant cysts such as mucinous cystic neoplasms, intraductal papillary mucinous neoplasms, cystic degeneration associated with solid tumors such as pancreatic ductal adenocarcinoma or pancreatic endocrine neoplasms, and solid pseudopapillary neoplasms. The clinical challenge in 2017 is to accurately preoperatively diagnose them and their malignant potential before deciding about surgery, surveillance or doing nothing. This review will focus on the currently available clinical guidelines for doing so.

Evaluation of the 2015 AGA guidelines on pancreatic cystic neoplasms in a large surgically confirmed multicenter cohort

Background and study aims The American Gastroenterological Association (AGA) recently published guidelines for the management of asymptomatic pancreatic cystic neoplasms (PCNs). We aimed to evaluate the diagnostic characteristics of the AGA guidelines in appropriately recommending surgery for malignant PCNs. Patients and methods A retrospective multicenter study was performed of patients who underwent endoscopic ultrasound (EUS) for evaluation of PCNs who ultimately underwent surgical resection from 2004 - 2014. Demographics, EUS characteristics, fine-needle aspiration (FNA) results, type of resection, and final pathologic diagnosis were recorded. Patients were categorized into 2 groups (surgery or surveillance) based on what the AGA guidelines would have recommended. Performance characteristics for the diagnosis of cancer or high-grade dysplasia (HGD) on surgical pathology were calculated. Results Three hundred patients underwent surgical resection for PCNs, of whom the AGA guidelines would have recommended surgery in 121 (40.3 %) and surveillance in 179 (59.7 %) patients. Among patients recommended for surgery, 45 (37.2 %) had cancer, whereas 76 (62.8 %) had no cancer/HGD. Among patients recommended for surveillance, 170 (95.0 %) had no cancer/HGD; however, 9 (5.0 %) patients had cancer that would have been missed. For the finding of cancer/HGD on surgical pathology, the AGA guidelines had 83.3 % sensitivity (95 % CI 70.7 - 92.1), 69.1 % specificity (95 % CI 62.9 - 74.8), 37.2 % positive predictive value (95 % CI 28.6 - 46.4), 95.0 % negative predictive value (95 % CI 90.7 - 97.7), and 71.7 % accuracy (95 % CI 67.4 - 74.6). Conclusions The 2015 AGA guidelines would have resulted in 60 % fewer patients being referred for surgical resection, and accurately recommended surveillance in 95 % of patients with asymptomatic PCNs. Future prospective studies are required to validate these guidelines. Meeting presentations: Presented in part at Digestive Diseases Week 2016.