High-grade dysplasia and adenocarcinoma are frequent in side-branch intraductal papillary mucinous neoplasm measuring less than 3 cm on endoscopic ultrasound

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.

Glycemic Abnormalities in Pancreatic Cystic Lesions—A Single-Center Retrospective Analysis

Background and Objectives: Glucose metabolism alterations are very common in solid pancreatic lesions, particularly in pancreatic cancer. Similarly, diabetes and especially new-onset diabetes (NOD) have been associated with the malignant transformation of pancreatic cysts. We aimed to assess the prevalence and relevant associations of glycemic abnormalities in pancreatic cystic lesions (PCLs) in a retrospective analysis. Materials and Methods: We retrospectively recruited all patients who underwent endoscopic ultrasound for a PCL over a period of 36 months (January 2018 to December 2021). Final diagnosis was set by means of tissue acquisition, surgery, follow-up, or board decision. Demographic and clinical data, laboratory workup, and imaging features were extracted from the patients’ charts according to a predefined protocol. We considered fasting blood glucose (FBG) and HbA1c values and stratified the patients as nondiabetic (FBG ≤ 99 mg/dL, HbA1c ≤ 5.6%, no history of glycemic abnormalities), prediabetic (FBG 100–125 mg/dL, HbA1c 5.7–6.4%), or diabetic (long-lasting diabetes or NOD). Results: Altogether, 81 patients were included, with a median age of 66 years, and 54.3% of them were male. The overall prevalence of fasting hyperglycemia was 54.3%, comprising 34.6% prediabetes and 22.2% diabetes, of which 16.7% had NOD. The mean FBG and HbA1c levels were higher in malignant and premalignant PCLs (intraductal papillary mucinous neoplasm (IPMN), mucinous cystic neoplasm (MCN), cystadenocarcinoma, and cystic neuroendocrine tumor) compared to the benign lesions (pseudocysts, walled-off necrosis, and serous cystadenoma): 117.0 mg/dL vs. 108.3 mg/dL and 6.1% vs. 5.5%, respectively. Conclusions: Hyperglycemia and diabetes are common in PCLs, with a high prevalence in premalignant and malignant cysts. Screening and follow-up for glycemic abnormalities should be routinely conducted for PCLs, as they can contribute to a tailored risk assessment of cysts.

Resektionsstrategien beim BD-IPMN - Enukleation oder onkologische Resektion?

Hintergrund Das maligne Potenzial und die chirurgische Behandlung intraduktaler papillärer muzinöser Neoplasien der Seitengänge der Bauchspeicheldrüse (BD-IPMNs) bleiben umstritten. Die Enukleation (EN) als parenchymsparende Resektion des Pankreas kann eine wertvolle Alternative zu Standardresektionen (SR), z. B. Whipple oder distale Pankreatektomie, für die Behandlung von BD-IPMNs darstellen, ihre Rolle ist jedoch noch unzureichend definiert. Ziel dieser Übersichtsarbeit ist es, Indikationen und postoperative Ergebnisse nach Pankreas-Enukleation im Vergleich zur Standardresektion (SR) zu vergleichen.

Methoden Es wurde eine selektive Literaturrecherche durchgeführt. Die postoperativen Kurz- und Langzeitergebnisse beider Operationsverfahren wurden ausgewertet.

Ergebnisse Die EN ist im Vergleich zur SR mit einer kürzeren Operationszeit und einem geringeren Blutverlust verbunden. Die chirurgische Gesamtmorbidität unterscheidet sich nicht zwischen den beiden Verfahren. Obwohl die EN weniger invasiv ist, stellt die Entwicklung einer Pankreasfistel die häufigste Komplikation nach EN dar, und in mehreren Studien wird über eine höhere Rate an Pankreasfisteln nach EN als nach SR berichtet. Die Unterschiede, bezogen auf die Pankreasfistel, werden zwischen den beiden Verfahren in High-Volume-Zentren abgemildert. Die EN ermöglicht im Vergleich zur SR öfter den Erhalt der exokrinen und endokrinen Funktion der Bauchspeicheldrüse, dies ist der wichtigste Vorteil dieses Verfahrens.

Schlussfolgerungen Die EN scheint eine sichere und wirksame Alternative in der Behandlung der Seitengang-IPMN mit geringem Risiko zu sein, die den Erhalt der endokrinen und exokrinen Funktion ermöglicht. Außerdem sind die postoperativen Komplikationen und Rezidivraten nach EN vergleichbar mit den wesentlich umfangreicheren chirurgischen Verfahren. Die EN der Bauchspeicheldrüse sollte jedoch von erfahrenen Chirurgen durchgeführt werden. Da es sich um ein nicht onkologisches Verfahren handelt, muss die Auswahl der Patienten sehr genau erfolgen, was die Bedeutung der Behandlung in Einrichtungen mit hohem Patientenaufkommen unterstreicht.

Pancreatic ductal adenocarcinomas associated with intraductal papillary mucinous neoplasms (IPMNs) versus pseudo-IPMNs: relative frequency, clinicopathologic characteristics and differential diagnosis

The literature is highly conflicted on what percentage of pancreatic ductal adenocarcinomas (PDACs) arise in association with intraductal papillary mucinous neoplasms (IPMNs). Some studies have claimed that even small (Sendai-negative) IPMNs frequently lead to PDAC. Recently, more refined pathologic definitions for mucin-lined cysts were provided in consensus manuscripts, but so far there is no systematic analysis regarding the frequency and clinicopathologic characteristics of IPMN-mimickers, i.e., pseudo-IPMNs. In this study, as the first step in establishing frequency, we performed a systematic review of the pathologic findings in 501 consecutive ordinary PDACs, which disclosed that 10% of PDACs had associated cysts ≥1 cm. While 31 (6.2%) of these were IPMN or mucinous cystic neoplasm (MCN), 19 (3.8%) were other cyst types that mimicked IPMN (pseudo-IPMNs) per recent WHO/consensus criteria. As the second step of the study, we performed a comparative clinicopathologic analysis by also including our entire surgical pathology/consultation databases that was comprised of 60 IPMN-associated PDACs, 30 MCN-associated PDACs and 40 pseudo-IPMN-associated PDACs. We found that 84% of true IPMNs were pre-operatively recognized, whereas IPMN was considered in differential diagnosis of 33% of pseudo-IPMNs. Of the 40 pseudo-IPMNs, there were 15 secondary duct ectasias; 6 large-duct-type PDACs; 5 pseudocysts; 5 cystic tumor necrosis; 4 simple mucinous cysts; 3 groove pancreatitis-associated paraduodenal wall cysts; and 2 congenital cysts. Microscopically, pseudo-IPMNs had at least partial mucinous-lining mimicking IPMN but had smaller cystic (mean = 1.9 cm) and larger PDAC (mean = 3.8 cm) components compared to true IPMNs (cyst = 5.7 cm; PDAC = 2.0 cm). In summary, in this pathologically verified analysis that utilized refined criteria, 10% of PDACs were discovered to have cysts ≥1 cm, about two-thirds of which were IPMN/MCN but about one-third were pseudo-IPMNs. True IPMNs underlying the PDACs are often large and are already diagnosed pre-operatively as having an IPMN component, whereas only a third of the pseudo-IPMNs receive IPMN diagnosis by imaging and their cysts are smaller. At the histopathologic level, pseudo-IPMNs are highly prone to misdiagnosis as IPMN, which presumably accounts for much higher association of IPMNs with PDAC as reported in some studies. The subtle but salient characteristics of pseudo-IPMNs elucidated in this study should be combined with careful radiological/clinical correlation in order to exclude pseudo-IPMNs.

Branch-duct intraductal papillary mucinous neoplasm (IPMN): Are cyst volumetry and other novel imaging features able to improve malignancy prediction compared to well-established resection criteria?

OBJECTIVES

Current guidelines base the management of intraductal papillary mucinous neoplasms (IPMN) on several well-established resection criteria (RC), including cyst size. However, malignancy may occur in small cysts. Since branch-duct (BD) IPMN are not perfect spheres, volumetric and morphologic analysis might better correlate with mucin production and grade of dysplasia. Nonetheless, their role in malignancy (high-grade dysplasia/invasive cancer) prediction has been poorly investigated. Previous studies evaluating RC also included patients with solid-mass-forming pancreatic cancer (PC), which may affect the RC yield. This study aimed to assess the role of volume, morphology, and other well-established RC in malignancy prediction in patients with BD- and mixed-type IPMN after excluding solid masses.

METHODS

Retrospective ethical review-board-approved study of 106 patients (2008-2019) with histopathological diagnosis of BD- and mixed-type IPMN (without solid masses) and preoperative MRI available. Standard imaging and clinical features were collected, and the novel imaging features cyst-volume and elongation value [EV = 1 - (width/length)] calculated on T2-weighted images. Logistic regression analysis was performed. Statistical significance set at two-tails, p < 0.05.

RESULTS

Neither volume (odds ratio (OR) = 1.01, 95% CI: 0.99-1.02, p = 0.12) nor EV (OR = 0.38, 95% CI: 0.02-5.93, p = 0.49) was associated with malignancy. Contrast-enhancing mural nodules (MN), main pancreatic duct (MPD) ≥ 5 mm, and elevated carbohydrate antigen (CA) 19-9 serum levels (> 37 μmol/L) were associated with malignancy (MN OR: 4.32, 95% CI: 1.18-15.76, p = 0.02; MPD ≥ 5 mm OR: 4.2, 95% CI: 1.34-13.1, p = 0.01; CA19-9 OR: 6.72; 95% CI: 1.89 - 23.89, p = 0.003).

CONCLUSIONS

Volume and elongation value cannot predict malignancy in BD- and/or mixed-type IPMN. Mural nodules, MPD ≥ 5 mm and elevated CA19-9 serum levels are associated with higher malignancy risk even after the exclusion of solid masses.

KEY POINTS

• Novel and well-established resection criteria for IPMN have been evaluated after excluding solid masses. • BD-IPMN volume and elongation value cannot predict malignancy. • Main pancreatic duct ≥ 5 mm, mural nodules, and elevated carbohydrate antigen 19-9 levels are associated with malignancy.

Long-term follow-up of Branch-Duct Intraductal Papillary Mucinous Neoplasms with negative Sendai Criteria: the therapeutic challenge of patients who convert to positive Sendai Criteria

BACKGROUND

The management of Branch-Duct Intraductal Papillary Mucinous Neoplasm (BD-IPMN) is still controversial. Our objective was to assess the long-term follow-up (FU) of patients with "low-risk" BD-IPMN according to the Sendai-International Consensus Guidelines (ICG-I).

METHODS

We retrospectively analyzed a cohort of patients with BD-IPMN and Negative Sendai-Criteria (NSC) from January 2004 to October 2019. A univariate analysis was performed to determine factors associated with conversion to Positive Sendai-Criteria (PSC) and malignancy. Positive Predictive Value (PPV) and Negative Predictive Value (NPV) of the IGC-I were assessed for the development of malignancy.

RESULTS

A total of 219 patients were selected and underwent a median 58-month FU. Thirty-seven (17%) patients developed PSC during FU including 12 (5.5%) with malignant lesions. Conversely, 182 patients (83%) did not develop malignancy. The NPV and PPV of ICG-I for malignancy were 100% and 32.4%, respectively. Among patients who developed PSC, those with cancer were >65years (OR = 3.57;p = 0.015) and had significantly higher serum CA-19-9 levels (OR = 5.27;p = 0.007).

CONCLUSION

The ICG-I is a safe strategy for FU of patients with BD-IPMN. The absence of PSC exclude malignancy. Among patients who develops PSC, the risk of cancer remains low and surgery should be decided according to their surgical risk and life expectancy.

Validation of Indications for Surgery of European Evidence-Based Guidelines for Patients with Pancreatic Intraductal Papillary Mucinous Neoplasms

BACKGROUND

Which patients with pancreatic intraductal papillary mucinous neoplasms (IPMNs) should undergo surgical intervention remains a controversial issue. The aim of this retrospective study was to validate the new European evidence-based guidelines on pancreatic cystic neoplasms (EEBGPCN) for the management of IPMNs.

METHODS

One hundred fifty-eight patients with resected IPMNs at National Taiwan University Hospital between January 1994 and December 2016 were enrolled. Clinical information, including new-onset diabetes mellitus (DM) and preoperative CA 19-9 levels, were collected. All patients were stratified into three groups-absolute, relative indications, and conservative approach-according to EEBGPCN. The performance characteristics of EEBGPCN for high-grade dysplasia (HGD)/invasive carcinoma (IC) of IPMNs were calculated.

RESULTS

One hundred seven (67.7%) patients with low-grade dysplasia and 51 patients with HGD/IC, including 10 HGD and 41 IC, were analyzed. The missed rate for HGD/IC by EEBGPCN was 1.9% (3/158). The sensitivity, specificity, positive and negative predictive values, and accuracy of the absolute or relative indications for resecting IPMN according to EEBGPCN were 94.1%, 28.0%, 38.4%, 90.9%, and 49.4%. Jaundice, enhancing mural nodule < 5 mm, cyst diameter > 40 mm, increased levels of serum CA 19-9, new-onset DM, and main pancreatic duct dilation were associated with HGD/IC.

CONCLUSIONS

The missed rate for HGD/IC is low by EEBGPCN. Increased serum CA 19-9 and new-onset DM in EEBGPCN were verified as the indications for the surgical resection of IPMNs.

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.

Predictive Features of Malignancy in Branch Duct Type Intraductal Papillary Mucinous Neoplasm of the Pancreas: A Meta-Analysis

Simple Summary

Currently, there are several guidelines that are widely used to establish the treatment strategy for branch duct type intraductal papillary mucinous neoplasms. Although there are some common grounds, there are discrepancies on which features they adopt, how much each feature is weighted, and how the features are combined. Furthermore, some of the features are based on lower level evidences or expert opinions. The aim of this meta-analysis was to investigate important clinical, radiological, and biochemical risk factors for malignancy and their impact as predictors. This study found symptom, size, cyst wall thickening, presence of mural nodule, change in main pancreatic duct caliber, lymphadenopathy, CA 19-9, and CEA as risk factors. Lymphadenopathy (odd ratio [OR]: 8.55), abrupt caliber change (OR: 7.41), and mural nodule (OR: 4.10) had the highest odd ratios. We expect the higher level evidences of this study to help shape better guidelines and reduce discrepancies among future guidelines.

Abstract

The current guidelines on branch duct type intraductal papillary mucinous neoplasm (BD-IPMN) recommend various predictive features of malignancy as well as different treatment strategies. This study aimed to identify the risk factors for malignancy with higher level of evidence. A meta-analysis was performed on 40 literatures published between 2000 and 2019. These literatures included 6301 patients with pathologically proven IPMN. Malignancy was defined as high-grade dysplasia and invasive carcinoma. It was significantly associated with symptoms (odds ratio [OR] 1.35, confidence interval [CI] 1.01–1.79), size ≥ 3 cm (OR 1.90, CI 1.51–2.40), cystic wall thickening (OR 2.53, CI 1.50–4.27), mural nodule (OR 4.10, CI 3.38–4.97), main pancreatic duct dilatation (OR 2.98, CI 2.11–4.21), abrupt caliber change of the pancreatic duct (OR 7.41, CI 2.49–22.06), lymphadenopathy (OR 8.55, CI 3.25–22.51), elevated carbohydrate antigen 19-9 (OR 4.01, CI 2.55–6.28), and elevated carcinoembryonic antigen (OR 2.04, CI 1.60–2.61). Multilocular cysts and multiple cysts did not show a significant association with malignancy. This study examined the clinical, radiological, and biochemical features of BD-IPMN, often used as malignancy predictors according to the widely used guidelines. The results confirmed that all the features currently being used are valid.

[Quality of indications in cystic lesions of the pancreas]

Cystic tumors of the pancreas (PCN) have increasingly gained importance in the clinical routine as they are frequently diagnosed as an incidental finding due to the continuous improvement in cross-sectional imaging. A differentiation is made between non-neoplastic and neoplastic cysts, whereby the latter has a tendency to malignant transformation to a varying extent. Therefore, they can be considered as precursor lesions of pancreatic cancer (PDAC). In addition to a detailed patient history and examination, imaging modalities, such as computed tomography (CT), magnetic resonance imaging (MRI) and endoscopic ultrasound (EUS) with fine needle aspiration (FNA) are used for the differential diagnosis. The indications for surgical resection of these lesions are based on the current European guidelines from 2018; however, the content is not evidence-based but relies on knowledge and recommendations from experts. According to these consensus recommendations asymptomatic serous cystic neoplasms (SCN) are serous lesions with a low tendency for malignant transformation and can be monitored. In contrast resection is warranted for all mucinous cystic neoplasms (MCN) >4 cm and all solid pseudopapillary neoplasms (SPN). Intraductal papillary mucinous neoplasms (IPMN), which are differentiated into main duct (MD-IPMN) and branch duct type (BD-IPMN) IPMN based on the position in the pancreatic duct system, should be resected as MD-IPMN and mixed type (MT)-IPMN. The risk of malignant transformation in BD-IPMN is variable and depends on risk factors, which are defined clinically and by imaging morphology. The treatment management is therefore carried out on an individual basis following risk estimation. In order to quantify the quality of indications in PCN and thereby also contributing to optimized medical care, prospective long-term studies are urgently needed.

Enucleation for branch duct intraductal papillary mucinous neoplasms: a systematic review and meta-analysis

BACKGROUND

The role of enucleation (EN) for branch duct intraductal papillary mucinous neoplasms (BD-IPMN) is poorly defined. This systematic review aims to review EN for BD-IPMN and compare it with pancreatic resection (pancreaticoduodenectomy, distal pancreatectomy and central pancreatectomy).

METHODS

A systematic review of published literature was performed using PRISMA guidelines, and included a search of PubMed, MEDLINE and SCOPUS databases.

RESULTS

Sixteen studies were included in the final analysis comprising 991 patients with 293 EN patients and 698 resected patients. EN was most often performed for low grade (77%, 151/197) BD-IPMN's (99%, 251/253) of the pancreatic head (64%, 106/165), with a pooled mean diameter of 21 mm (SD 28 mm). EN was a shorter procedure (MD -115.8 min, CI -142.2 to -89.5 min, P=<0.001) with a lower rate of post-pancreatectomy haemorrhage (EN 1% 2/144, Resection 5% 10/186, RR 0.32, CI 0.11 to 0.94, P = 0.043) and postoperative exocrine and endocrine insufficiency (P = <0.001 and P = 0.003 respectively) than resection.

CONCLUSION

EN for BD-IPMN's appears to be a reasonable alternative to resection in low risk BD-IPMN's, allowing preservation of exocrine and endocrine function with comparable reoperation and recurrence rates to resection. However, surveillance was indicated in these low risk patients based on current published guidelines.

Etiologic Distribution of Pancreatic Cystic Lesions Identified on Computed Tomography/Magnetic Resonance Imaging

OBJECTIVES

This study aimed to determine the distribution of etiology of pancreatic cysts using established criteria/markers from cyst fluid analysis and cytology that have been reported to have high specificity in published literature.

METHODS

A retrospective study of pancreatic cysts using an endoscopic database from March 2002 and May 2013 was conducted. Pancreatic cysts <10 mm and cysts with a history of pancreatic cancer were excluded.

RESULTS

In our cohort of 758 patients with pancreatic cyst(s), the cyst etiology was as follows: mucinous cyst/side-branch intraductal papillary mucinous neoplasms (SB-IPMNs)/mucinous cystic neoplasms (MCN; 48.2%), pseudocyst (27.6%), serous cystadenoma (11%), simple cysts (6.4%), mucinous cystadenocarcinoma (5.1%), and other (1%). Approximately 41% (n = 310) of the cysts were ≥3 cm in size and included the following: pseudocyst (39.7%), mucinous cysts/SB-IPMN/MCN (28.1%), serous cystadenoma (16.7%), mucinous cyst adenocarcinoma (9.7%), and simple cyst (4.8%). In 118 patients with a known history of acute pancreatitis, the cyst diagnoses included pseudocyst (68.7%), mucinous cyst/SB-IPMN/MCN (18.6%), benign/simple cyst (7.6%), and mucinous cystadenocarcinoma (2.5%).

CONCLUSIONS

In patients with cystic pancreatic lesion noted on cross-sectional imaging, approximately half of the patients have lesions without malignancy or malignant potential and therefore not requiring surveillance. Endoscopic ultrasound/endoscopic ultrasound-guided fine-needle aspiration evaluation of the pancreatic cysts can help optimize their further management.

Management and outcomes of intraductal papillary mucinous neoplasms

Background

This study evaluated the outcome and survival of patients with radiologically suspected intraductal papillary mucinous neoplasms (IPMNs).

Methods

IPMN management was reviewed according to Fukuoka risk factors and IPMN localization, differentiating main‐duct (MD), mixed‐type (MT) and branch‐duct (BD) IPMNs. Perioperative results were compared with those of patients undergoing resection of pancreatic ductal adenocarcinoma (PDAC) over the same interval (2010–2014). Overall (OS) and disease‐specific (DSS) survival rates were calculated and subgroups compared.

Results

Of 142 patients with IPMNs, 26 had MD‐IPMN, eight had MT‐IPMN and 108 had BD‐IPMN. Some 74 per cent of patients with MD‐ and MT‐IPMN were managed by primary resection, whereas this was used in only 27·8 per cent of those with BD‐IPMN. The risk of secondary resection and malignant transformation for BD‐IPMNs smaller than 20 mm was 8 and 2 per cent respectively during follow‐up. Pancreatic head resection of IPMNs was associated with an increased risk of postoperative pancreatic fistula grade B/C compared with resection of PDAC (12 of 33 (36 per cent) versus 41 of 221 (18·6 per cent) respectively; P = 0·010), and greater morbidity and mortality (Clavien–Dindo grade III: 15 of 33 (45 per cent) versus 56 of 221 (25·3 per cent) respectively; grade IV: 1 (3 per cent) versus 7 (3·2 per cent); grade V: 2 (6 per cent) versus 2 (0·9 per cent); P = 0·008). Five‐year OS and DSS rates in patients with MD‐IPMN were worse than those for MT‐ and BD‐IPMN (OS: 44, 86 and 97·4 per cent respectively, P < 0·001; DSS: 60, 100 and 98·6 per cent; P < 0·001). Patients with invasive IPMN had worse OS and DSS rates than those with non‐invasive dysplasia (OS: IPMN‐carcinoma (10 patients) 33 per cent, high‐grade dysplasia 100 per cent, intermediate‐grade dysplasia 63 per cent, low grade‐dysplasia 100 per cent, P < 0·001; DSS: IPMN‐carcinoma 43 per cent, all grades of dysplasia 100 per cent, P < 0·001). Patients with high‐risk stigmata had poorer survival than those without risk factors (OS: high‐risk stigmata (35 patients) 55 per cent, worrisome features (31) 95 per cent, no risk factors (76) 100 per cent, P < 0·001; DSS: 71, 100 and 100 per cent respectively, P < 0·001).

Conclusion

The risk of malignant transformation was very low for BD‐IPMNs, but the development of high‐risk stigmata was associated with disease‐specific mortality. Patients with IPMN had greater morbidity after resection than those having resection of PDAC.

Transmembrane mucin MUC13 distinguishes intraductal papillary mucinous neoplasms from non-mucinous cysts and is associated with high-risk lesions

BACKGROUND

Intraductal papillary mucinous neoplasms (IPMN) are currently managed based on imaging characteristics and cyst fluid sampling. This study was designed to determine if MUC13, a glycoprotein aberrantly overexpressed in pancreatic adenocarcinoma, might aid in distinguishing high-risk lesions (high grade dysplasia/invasive disease) from low-grade lesions.

METHODS

MUC13 immunohistochemical staining was performed on surgically resected formalin-fixed tissue specimens from 49 IPMNs and 23 non-mucinous cysts. Membranous MUC13 expression was measured by H-score, which quantifies staining intensity and the percentage of cells involved (range 0-300).

RESULTS

MUC13 expression was detected in all IPMNs and was significantly greater than in non-mucinous cysts (median 210 vs 40, p < 0.001). MUC13 expression was similar among main (n = 26), branch (n = 15), and mixed (n = 8) duct lesions (median 210, 200, 225, respectively). The highest expression was observed in tumors with intestinal and pancreatobiliary histologic features (both median 225) and the lowest in gastric type lesions (median 200). MUC13 expression was significantly greater in high-risk lesions (n = 21) compared to those with low-grade dysplasia (n = 28) (median 250 vs 195, p < 0.001).

CONCLUSION

MUC13 expression was significantly greater in high-risk IPMNs in this analysis. The preoperative assessment of MUC13 in cyst fluid samples warrants further investigation.

Clinical Management and Surgical Decision-Making of IPMN of the Pancreas

Intraductal papillary mucinous neoplasm (IPMN) is the most common pancreatic cystic neoplasm (PCN). The increased attention to IPMN is due to its unique features of malignant progression, being different between main duct IPMN and branch duct IPMN, and increased de novo development of conventional pancreatic ductal adenocarcinoma elsewhere in the pancreas. The increased interest in IPMN led to publication of many guidelines on its clinical management. This chapter aims to summarize and compare characteristics of nine guidelines on the clinical management of IPMN and other PCNs published in the English literature and further to show a current strategy for surgical decision making in the management of IPMN.

Imaging and Cytopathological Criteria Indicating Malignancy in Mucin-Producing Pancreatic Neoplasms: A Series of 68 Histopathologically Confirmed Cases

OBJECTIVES

This study aims to evaluate the performance of clinical, imaging, and cytopathological criteria in the identification of high-grade dysplasia/carcinoma (HGD/Ca) in pancreatic mucin-producing cystic neoplasms.

METHODS

Sixty-eight consecutive, histopathologically confirmed mucin-producing cystic neoplasms, evaluated by endoscopic ultrasound-guided fine-needle aspiration, were enrolled; specifically, 39 branch duct intraductal papillary mucinous neoplasms (BD-IPMNs), 21 main duct IPMNs, and 8 mucinous cystic neoplasms. The associations between HGD/Ca in histopathology and findings of endoscopic ultrasound and cytology, demographic, lifestyle, and clinical parameters were evaluated, separately in IPMNs and mucinous cystic neoplasms.

RESULTS

Age 65 years or more was associated with HGD/Ca in IPMNs. In BD-IPMNs, cyst diameter 3 cm or greater (sensitivity, 68.8%; specificity, 65.2%), a mural nodule (sensitivity, 56.3%; specificity, 78.3%), main pancreatic duct diameter 5 to 9 mm (sensitivity, 50.0%; specificity, 87.0%), and suspicious cytology (sensitivity, 81.3%; specificity, 100%) signaled the presence of HGD/Ca. Similarly, in main duct IPMNs, suspicious cytology predicted HGD/Ca with high sensitivity (88.9%) and excellent specificity (100%). Regarding cytopathological criteria, in BD-IPMNs, HGD/Ca was associated with a high nuclear/cytoplasmic ratio, background necrosis, presence of papillary structures, hypochromatic nuclei, hyperchromatic nuclei, and major nuclear membrane irregularities (thickening and/or indentations).

CONCLUSIONS

Clinical, imaging, and cytopathological criteria are useful in the identification of HGD/Ca in IPMNs.

Does cyst growth predict malignancy in branch duct intraductal papillary mucinous neoplasms? Results of a large multicenter experience

BACKGROUND

Cyst growth of BD-IPMNs on follow-up imaging remains a concerning sign.

AIMS

To describe cyst size changes over time in BD-IPMNs, and determine whether cyst growth rate is associated with increased risk of malignancy.

METHODS

This is a retrospective study performed at two high volume tertiary centers. Mean cyst size at baseline (MCSB) and mean growth rate percentage (MGRP) were calculated. Rapid cyst growth was defined as MGRP ≥30%/year. Patient and cyst related characteristics were studied.

RESULTS

160 patients were followed for a median of 27.4 (12-114.5) months. MCSB was 15.1 ± 8.0 mm. During follow-up, 73 (45.6%) showed any cyst size increase, of which 15 cysts (9.4%) exhibited MGRP ≥30%/year. Rapid cyst growth was not associated with patient or cyst characteristics. Cyst fluid molecular analysis from 101 cysts showed KRAS mutation in 26. Compared to KRAS-negative cysts, neither MCSB (16.0 mm vs. 17.7 mm; p = 0.3) nor MGRP (3.9%/year vs. 5.8%/year; p = 0.7) was significantly different. Eighteen patients underwent surgery; 15 (83%) had LGD, and 3 had advanced neoplasia. Two cysts with LGD and one cyst with advanced neoplasia had MGRP ≥30%/year.

CONCLUSION

Increase in BD-IPMNs size was not associated with the known high risk patient or cyst-related characteristics. Rapid growth of BD-IPMNs was not associated with advanced neoplasia on surgical pathology.

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.

Clinicopathological and prognostic significance of MUC13 and AGR2 expression in intraductal papillary mucinous neoplasms of the pancreas

BACKGROUND

Intraductal papillary mucinous neoplasm (IPMN) of the pancreas is a primary pancreatic ductal epithelial neoplasm with the potential to develop into an invasive adenocarcinoma. This study aimed to investigate the clinicopathologic and prognostic significance of four potential biomarkers for the preoperative evaluation of patients with IPMN.

MATERIALS AND METHODS

Clinicopathologic materials from 104 patients with IPMN who underwent surgical resection at Jichi Medical University Hospital were analyzed. IPMNs (110 lesions in total) were histologically classified into low-grade IPMN (Group 1; n = 68), high-grade IPMN (Group 2; n = 16), or IPMN with an associated invasive carcinoma (Group 3; n = 26). We evaluated the immunohistochemical expression of MUC13, AGR2, FUT8, and FXYD3, which were previously reported to be overexpressed in pancreatic ductal adenocarcinoma.

RESULTS

The expression of MUC13 was more common in Group 3 compared with groups 1 and 2 (p < 0.001) and was associated with poor prognosis (p = 0.004). The expression of MUC13 was not associated with age, sex, tumor location, histological subtype, lymphatic or vascular invasion, or neural invasion. In most cases of IPMN, the loss of expression of AGR2 appeared to show an association with tumor recurrence and poorly differentiated histology of invasive carcinoma; however, this association was not statistically significant. The expressions of FUT8 and FXYD3were not associated with the clinicopathological features of IPMNs.

CONCLUSIONS

The results suggest that MUC13 overexpression and loss of expression of AGR2 may predict the progression of IPMN and an unfavorable prognosis in patients with IPMN.

European evidence-based guidelines on pancreatic cystic neoplasms

Evidence-based guidelines on the management of pancreatic cystic neoplasms (PCN) are lacking. This guideline is a joint initiative of the European Study Group on Cystic Tumours of the Pancreas, United European Gastroenterology, European Pancreatic Club, European-African Hepato-Pancreato-Biliary Association, European Digestive Surgery, and the European Society of Gastrointestinal Endoscopy. It replaces the 2013 European consensus statement guidelines on PCN. European and non-European experts performed systematic reviews and used GRADE methodology to answer relevant clinical questions on nine topics (biomarkers, radiology, endoscopy, intraductal papillary mucinous neoplasm (IPMN), mucinous cystic neoplasm (MCN), serous cystic neoplasm, rare cysts, (neo)adjuvant treatment, and pathology). Recommendations include conservative management, relative and absolute indications for surgery. A conservative approach is recommended for asymptomatic MCN and IPMN measuring <40 mm without an enhancing nodule. Relative indications for surgery in IPMN include a main pancreatic duct (MPD) diameter between 5 and 9.9 mm or a cyst diameter ≥40 mm. Absolute indications for surgery in IPMN, due to the high-risk of malignant transformation, include jaundice, an enhancing mural nodule >5 mm, and MPD diameter >10 mm. Lifelong follow-up of IPMN is recommended in patients who are fit for surgery. The European evidence-based guidelines on PCN aim to improve the diagnosis and management of PCN.

The 2012 International Consensus Guidelines of Intraductal Papillary Mucinous Neoplasms of the Pancreas (Fukuoka Criteria) Predict the Malignant Potential, Even in Actual Clinical Situations

OBJECTIVES

The aim of the present study was to validate the use of the 2012 International Consensus Guidelines for intraductal papillary mucinous neoplasm (IPMN) (Fukuoka criteria) in patients without findings of obstructive jaundice and/or an enhanced solid component.

METHODS

This retrospective study included patients who underwent pancreatectomy for IPMN between October 2002 and September 2016. The sensitivity, specificity, and positive and negative predictive values for malignancy were calculated for each feature of high-risk stigmata.

RESULTS

Of the 135 patients who underwent surgery for IPMN, 50 (37.0%) had low/intermediate-grade dysplasia, 25 (18.5%) had high-grade dysplasia, and the remaining 60 (44.5%) had invasive carcinoma. A malignant potential was, thus, present in 63% of all resected cases. Considering an actual clinical situation, the predictors for malignant potential were assessed in 62 patients without findings of obstructive jaundice and/or an enhanced solid component. A multivariate analysis revealed that the Fukuoka criteria were the only independent factor for predicting the malignant potential (odds ratio, 5.69; P = 0.036).

CONCLUSIONS

The present study suggested that malignant potential can be accurately detected by faithfully keeping to the Fukuoka criteria. Using these criteria enables us to identify patients with malignant potential, even in the actual clinical situations.

Intraductal Papillary Mucinous Neoplasms of the Pancreas: Strategic Considerations

Intraductal papillary mucinous neoplasms (IPMN) are cystic neoplasms with the potential for progression to pancreatic cancer. Recognized by the global medical community just over two decades ago, IPMN have gained great epidemiological and clinical relevance thanks to the widespread use of cross-sectional abdominal imaging, which has led to a surge in the number of incidental pancreatic cysts being diagnosed. As our understanding of this disease has improved, we now know that some IPMN have a very elevated risk of cancer and require surgical resection, while others are low-risk lesions and can be followed. The approach to IPMN must therefore strike a balance between preventing the over-utilization of surgery and the timely recognition and treatment of patients with high-risk lesions. Several clinical, radiographic, and laboratory parameters have been proposed to risk-stratify IPMN, leading to the publication of management guidelines that do not always converge in their recommendations. The goal of this clinical therapeutic review is to describe the strategic approach to IPMN at the Massachusetts General Hospital, and how our current understanding, management algorithm, and future directions have been informed by research efforts at our institution and other centers.

Prevalence of incidental pancreatic cyst on upper endoscopic ultrasound

Background:

This study aimed to determine the prevalence of incidental pancreatic cysts in patients undergoing upper endoscopic ultrasound without a known pancreatic abnormality.

Methods:

This prospective study was conducted in two hospitals in Spain and enrolled consecutive patients referred for upper endoscopic ultrasound for a condition unrelated to the pancreas. Patients with a previous pancreatic anomaly, history of acute or chronic pancreatitis, evidence of acute pancreatitis, previous upper gastrointestinal surgery, or chronic abdominal pain suggestive of pancreatic origin were excluded. Univariate logistic regression was performed to evaluate individual covariates and the incidental pancreatic cyst risk.

Results:

A total of 298 patients were included, of whom 64 had pancreatic cysts (21.5%; 16.9-26.6%). The mean size of the cysts was 6.3±3.7 (range 3-25) mm. Six cysts (2%) were >10 mm and 16 (5.4%) were compatible with branch duct intraductal papillary mucinous neoplasm. The pancreatic cyst prevalence was similar in the two hospitals and increased significantly with age.

Conclusion:

The prevalence of incidental pancreatic cysts during endoscopic ultrasound was very high in our study population.

Incidental, Small (< 3 cm), Unilocular, Pancreatic Cysts: Factors That Predict Lesion Progression during Imaging Surveillance

OBJECTIVE

To explore the features that predict size increase and development of potential malignant features in incidentally detected, unilocular cystic pancreatic lesions (CPLs) less than 3 cm in diameter, during subsequent follow-up.

MATERIALS AND METHODS

We retrieved data of patients diagnosed with unilocular CPLs less than 3 cm in diameter during the period from November 2003 through December 2014, using a computerized search. All serial CT and MR images were analyzed to identify the number, size, and location of CPLs; dilatation of the main pancreatic duct; and occurrence of worrisome features and high-risk stigmata of malignancy in the lesion. The characteristics of CPLs were compared between the increase (i.e., size increase during subsequent follow-up) and no-increase groups. For CPLs in the increase group, subgroup analysis was performed according to the lesion size at the last follow-up (< 3 cm vs. ≥ 3 cm).

RESULTS

Among 553 eligible patients, 132 (23.9%) had CPLs that increased in size, and 421 (76.1%) had CPLs that did not, during follow-up. Of the 132, 12 (9.1%) CPLs increased to diameters ≥ 3 cm at the final follow-up. Among the various factors, follow-up duration was a significant independent factor for an interval size increase of CPLs (p < 0.001). In the increase group, initial cyst size was a significant independent factor to predict later size increase to or beyond 3 cm in diameter (p < 0.001), and the initial cyst diameter ≥ 1.5 cm predicted such a growth with a sensitivity and specificity of 83% and 72%, respectively. No significant factors to predict the development of potential malignant features were identified.

CONCLUSION

Follow-up duration was associated with an interval size increase of CPLs. Among the growing CPLs, initial cyst size was associated with future lesion growth to and beyond 3 cm.

EUS Morphology Is Reliable in Selecting Patients with Mucinous Pancreatic Cyst(s) Most Likely to Benefit from Surgical Resection

Background and Study Aims

Endoscopic ultrasound (EUS) surveillance of patients with mucinous pancreatic cysts relies on the assessment of morphologic features suggestive of malignant transformation. These criteria were derived from the evaluation of surgical pathology in patients with pancreatic cysts who underwent surgery. Reliability of these criteria when evaluated by EUS in identifying lesions which require surgery has still not been established.

Patients and Methods

This retrospective cohort study included seventy-eight patients who underwent surgical resection of pancreatic cysts based on EUS-FNA (fine-needle aspiration) findings suggestive of mucinous pancreatic cysts with concern for malignancy.

Results

Final surgical pathology diagnoses of patients were the following: adenocarcinoma (19), intraductal papillary mucinous neoplasm (IPMN) (39), mucinous cystic neoplasm (MCN) (13), serous cystadenoma (2), pseudocyst (3), mucinous solid-cystic lesion of indeterminate type (1), and mesenteric cyst (1). Cysts with focal wall thickening ≥ 3 mm (p = 0.0008), dilation of pancreatic duct (PD) (p = 0.0067), and cyst size ≥ 3 cm (p = 0.016) had significantly higher risk of adenocarcinoma. None of the patients without any of these morphologic features had cancer.

Conclusions

In patients with mucinous pancreatic cyst(s), focal wall thickening, cyst size ≥ 3 cm, and PD dilation as assessed by EUS can help identify advanced mucinous cysts which require surgery and should routinely be evaluated during EUS surveillance.

[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.

Patterns of recurrence and long-term outcomes in patients who underwent pancreatectomy for intraductal papillary mucinous neoplasms with high grade dysplasia: implications for surveillance and future management guidelines

BACKGROUND

While intraductal papillary mucinous neoplasms (IPMNs) with high-grade dysplasia (HGD) are thought to represent non-invasive, high-risk lesions, its natural history following resection is unknown.

METHODS

A retrospective review of HGD-IPMN patients (1999-2015) was performed. Recurrence patterns and clinical outcomes following pancreatectomy were analyzed and the indications for surgery were explored based on current guidelines.

RESULTS

HGD was diagnosed in 100 of 314 patients (32%) following pancreatectomy for IPMN. IPMNs were classified as main duct, branch duct, or mixed in 15, 58 and 27 patients, respectively. Following resection, 25 patients had low-risk residual disease in the remnant pancreas. With a median follow-up of 35 months (range 1-129), 9 patients developed progressive or recurrent disease, 4 of whom underwent additional pancreatectomy. Three patients developed invasive adenocarcinoma. Median time to recurrence was 15 months (range 7-72). Based on the management algorithm from the international consensus guidelines, resection was indicated in 76 patients (76%). Other indications for surgery included mixed-duct IPMN(13), increased cyst size(7) and other(4).

CONCLUSION

The prognosis of HGD-IPMN following resection is good; however, HGD may be a marker for developing IPMN recurrence or adenocarcinoma. Current guidelines regarding surgical indications for IPMN can miss a significant number of patients with HGD.

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.

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.

Low progression of intraductal papillary mucinous neoplasms with worrisome features and high-risk stigmata undergoing non-operative management: a mid-term follow-up analysis

OBJECTIVE

To evaluate mid-term outcomes and predictors of survival in non-operated patients with pancreatic intraductal papillary mucinous neoplasms (IPMNs) with worrisome features or high-risk stigmata as defined by International Consensus Guidelines for IPMN. Reasons for non-surgical options were physicians' recommendation, patient personal choice or comorbidities precluding surgery.

METHODS

In this retrospective, multicentre analysis, IPMNs were classified as branch duct (BD) and main duct (MD), the latter including mixed IPMNs. Univariate and multivariate analysis for overall survival (OS) and disease-specific survival (DSS) were obtained.

RESULTS

Of 281 patients identified, 159 (57%) had BD-IPMNs and 122 (43%) had MD-IPMNs; 50 (18%) had high-risk stigmata and 231 (82%) had worrisome features. Median follow-up was 51 months. The 5-year OS and DSS for the entire cohort were 81% and 89.9%. An invasive pancreatic malignancy developed in 34 patients (12%); 31 had invasive IPMNs (11%) and 3 had IPMN-distinct pancreatic ductal adenocarcinoma (1%). Independent predictors of poor DSS in the entire cohort were age >70 years, atypical/malignant cyst fluid cytology, jaundice and MD >15 mm. Compared with MD-IPMNs, BD-IPMNs had significantly better 5-year OS (86% vs 74.1%, p=0.002) and DSS (97% vs 81.2%, p<0.0001). Patients with worrisome features had better 5-year DSS compared with those with high-risk stigmata (96.2% vs 60.2%, p<0.0001).

CONCLUSIONS

In elderly patients with IPMNs that have worrisome features, the 5-year DSS is 96%, suggesting that conservative management is appropriate. By contrast, presence of high-risk stigmata is associated with a 40% risk of IPMN-related death, reinforcing that surgical resection should be offered to fit patients.

The Sendai and Fukuoka consensus criteria for the management of branch duct IPMN - A meta-analysis on their accuracy

INTRODUCTION

The risk of malignancy in branch duct intraductal papillary mucinous neoplasia of the pancreas (BD-IPMN) is controversially debated. An increasing number of studies report on outcomes using the Sendai or Fukuoka consensus criteria for treatment decision-making. The objective of this work was to evaluate the diagnostic accuracy of the Sendai and Fukuoka criteria.

METHODS

We systematically reviewed studies on Sendai or Fukuoka criteria-guided management of BD-IPMN. Pooled sensitivity, specificity and diagnostic odds ratios as compound measures of diagnostic accuracy were calculated from studies matching the inclusion criteria. The meta-analysis was performed using a random effects model.

RESULTS

Fifteen studies with a total of 2710 patients were included. Twelve of these used the Sendai criteria. In these studies, 23% of Sendai-negative patients had a high grade dysplastic lesion or an invasive carcinoma in final histology. Pooled sensitivity was 56%, specificity was 74% and the diagnostic odds ratio for malignancy in Sendai-positive lesions was 7.45. When the results of follow-up examinations were included, diagnostic accuracy improved significantly (14.66, p < 0.001). Three studies were identified that used the Fukuoka criteria for decision making. Of 200 patients with Fukuoka-negative lesions who underwent surgery, 22 had a malignant lesion in final histology (11%). Pooled sensitivity was 83%, specificity was 53% and the diagnostic odds ratio was 8.76.

CONCLUSION

The Fukuoka criteria have considerably improved sensitivity but still lack adequate specificity. For further reduction of a potential surgical overtreatment of BD-IPMN, the development of criteria with an increased specificity is required.

Intraductal papillary mucinous neoplasms of the pancreas: reporting clinically relevant features

Intraductal papillary mucinous neoplasms (IPMNs) of the pancreas can exhibit a wide spectrum of macroscopic and microscopic appearances. This not only causes occasional difficulties for the reporting pathologist in distinguishing these tumours from other lesions, but is also relevant clinically. As evidence accumulates, it becomes clear that multiple macroscopic and histological features of these neoplasms are relevant to the risk for malignant transformation and, consequently, of prime importance for clinical patient management. The need for detailed reporting is therefore increasing. This review discusses the panoply of gross and microscopic features of IPMN as well as the recommendations from recent consensus meetings regarding the pathology reporting on this tumour entity.

Enucleation: A treatment alternative for branch duct intraductal papillary mucinous neoplasms

BACKGROUND

Small, asymptomatic, branch-duct intraductal papillary mucinous neoplasms of the pancreas are often kept under surveillance despite their malignant potential. The management of branch-duct intraductal papillary mucinous neoplasm is controversial with regard to indications and extent of any operative intervention. The present study aimed to evaluate enucleation as an alternative operative approach for branch-duct intraductal papillary mucinous neoplasms to exclude and prevent malignancy.

METHODS

For branch-duct intraductal papillary mucinous neoplasms of <30 mm in diameter and an acceptable distance from the main pancreatic duct, enucleation was considered as the operative approach of choice. All patients scheduled for enucleation of branch-duct intraductal papillary mucinous neoplasm on the basis of these features between January 2004 and September 2014 were analyzed. Among these, patients with successful enucleation were compared with those who were scheduled for enucleation but converted intraoperatively to pancreatic resection (intention-to-treat analysis). End points were hospital morbidity and mortality as well as histopathology and functional outcome at a mean follow-up of 32 months.

RESULTS

In the study, 115 patients with presumed branch-duct intraductal papillary mucinous neoplasm and the intention to perform pancreatic enucleation were included; 87 enucleations were performed in 74 patients. In 41 patients, enucleation was converted to a pancreatic resection (procedure-specific success rate 64%); indications for conversion included location or size (46%), presence of multicystic lesions (39%), or involvement of the main pancreatic duct (15%). Of the 74 patients with enucleation, 64 branch-duct intraductal papillary mucinous neoplasms revealed low- (85%), 11% moderate dysplasia-, and 4% high-grade dysplasia on histology. Among converted resections, 6 intraductal papillary mucinous neoplasms revealed high-grade dysplasia or invasive carcinoma (15%). Intention-to-treat analysis with patients converted to pancreatic resection showed that enucleations resulted in less blood loss (100 vs 400 mL) and a shorter operation time (146 vs 255 minutes; P < .001 each). Postoperative morbidity including postoperative pancreatic fistula was similar in both groups. No mortality occurred after enucleation; after formal resection, 1 patient died due to multiorgan failure. Both hospital stay (10 vs 14 days) and rates of postoperative endocrine and exocrine dysfunction rates were less after enucleation (P < .02 each). Intraductal papillary mucinous neoplasm-specific recurrence rates (3% vs 6%) were similar in both groups.

CONCLUSION

Enucleation is a safe procedure that can be performed successfully in a high proportion of branch-duct intraductal papillary mucinous neoplasms and should be considered instead of standard resections as an important function-preserving alternative. Limitations may occur due to malignancy, size, localization, multilocularity, or main-duct involvement requiring conversion to a formal, anatomic resection. Beside the advantages in the short-term course, functional outcome seems to be superior after enucleation, and intraductal papillary mucinous neoplasm-specific recurrence rates are not increased compared with standard resections, at least at a mean follow-up of 32 months.

Risk Factors for Malignancy of Branch-Duct Intraductal Papillary Mucinous Neoplasms: A Critical Evaluation of the Fukuoka Guidelines With a Systematic Review and Meta-analysis

OBJECTIVES

This study aimed to evaluate the accuracy of the risk factors proposed by Fukuoka guidelines in detecting malignancy of branch-duct intraductal papillary mucinous neoplasms.

METHOD

Diagnostic meta-analysis of cohort studies. A systematic literature search was conducted using MEDLINE, the Cochrane Library, Scopus, and the ISI-Web of Science databases to identify all studies published up to 2014.

RESULTS

Twenty-five studies (2025 patients) were suitable for the meta-analysis. The "high risk stigmata" showed the highest pooled diagnostic odds ratio (jaundice, 6.3; positive citology, 5.5; mural nodules, 4.8) together with 2 "worrisome features" (thickened/enhancing walls, 4.2; duct dilatation, 4.0) and 1 "other parameters" (carbohydrate antigen 19-9 serum levels, 4.6).

CONCLUSIONS

An "ideal risk factor" capable of recognizing all malignant branch-duct intraductal papillary mucinous neoplasms was not identified and some "dismal areas" remain. However, "high risk stigmata" were strongly related to malignancy, mainly enhancing mural nodules. Among the "worrisome features," duct dilatation and thickened/enhancing walls were underestimated, and their diagnostic performance was similar to those of "high risk stigmata." The carbohydrate antigen 19-9 serum level should be added to the Fukuoka algorithm because this value could help in carrying out correct management.

Utility of the 2006 Sendai and 2012 Fukuoka guidelines for the management of intraductal papillary mucinous neoplasm of the pancreas: A single-center experience with 138 surgically treated patients

This study aimed to evaluate the utility of the 2006 Sendai and 2012 Fukuoka guidelines for differentiating malignant intraductal papillary mucinous neoplasm (IPMN) of the pancreas from benign IPMN.Between January 2000 and March 2015, a total of 138 patients underwent surgery and had a pathologically confirmed pancreatic IPMN. Clinicopathological parameters were reviewed, and all patients were classified according to both the 2006 Sendai and 2012 Fukuoka guidelines. Univariate and multivariate analyses were used for identifying significant factors associated with malignancy in IPMN.There were 9 high-grade dysplasia (HGD) and 37 invasive cancers (ICs) in the 138 patients. The positive predictive value (PPV) and negative predictive value (NPV) of the Sendai and Fukuoka guidelines for HGD/IC was 35.1%, 43.3%, 100%, and 85.4%, respectively. Of the 36 patients with worrisome features using the Fukuoka guideline, 7 patients had HGD/IC in their IPMNs. According to the multivariate analysis, jaundice, tumors of ≥3 cm, presence of mural nodule on imaging, and aged <65 years were associated with HGD/IC in patients with IPMN.The Sendai guideline had a better NPV, but the Fukuoka guideline had a better PPV. We suggest that patients with worrisome features based on the Fukuoka guideline be aggressively managed.

Intraductal Papillary Mucinous Neoplasm of the Pancreas: Current State of the Art and Ongoing Controversies

With the widespread use and advances in radiographic imaging, Intraductal Papillary Mucinous Neoplasms (IPMNs) of the pancreas are identified with increasing frequency. Although many studies have addressed its biology and treatment, true understanding of its natural history continues to elude us. Its malignant potential places careproviders in a clinical dilemma of balancing the morbidity of pancreatectomy against the risk of malignant transformation while under continuous surveillance. Recently, there have been conflicting data published in the literature, generating more uncertainty in the field. In this article, we critically analyze the contrasting consensus guidelines from the International Association of Pancreatology and the American Gastroenterology Association, and address lingering questions and controversies. We also synthesize newly published data in the context of current standard of care, and provide a comprehensive review and recommendations for the clinical diagnosis, treatment, and follow-up strategy in the management of patients with Intraductal Papillary Mucinous Neoplasms.

Prevalence, Diagnosis and Management of Pancreatic Cystic Neoplasms: Current Status and Future Directions

Cystic neoplasms of the pancreas are found with increasing prevalence, especially in elderly asymptomatic individuals. Although the overall risk of malignancy is very low, the presence of these pancreatic cysts is associated with a large degree of anxiety and further medical investigation due to concerns about malignancy. This review discusses the different cystic neoplasms of the pancreas and reports diagnostic strategies based on clinical features and imaging data. Surgical and nonsurgical management of the most common cystic neoplasms, based on the recently revised Sendai guidelines, is also discussed, with special reference to intraductal papillary mucinous neoplasm (IPMN; particularly the branch duct variant), which is the lesion most frequently identified incidentally. IPMN pathology, its risk for development into pancreatic ductal adenocarcinoma, the pros and cons of current guidelines for management, and the potential role of endoscopic ultrasound in determining cancer risk are discussed. Finally, surgical treatment, strategies for surveillance of pancreatic cysts, and possible future directions are discussed.

American Gastroenterological Association guidelines are inaccurate in detecting pancreatic cysts with advanced neoplasia: a clinicopathologic study of 225 patients with supporting molecular data

BACKGROUND AND AIMS

The American Gastroenterological Association (AGA) recently reported evidence-based guidelines for the management of asymptomatic neoplastic pancreatic cysts. These guidelines advocate a higher threshold for surgical resection than prior guidelines and imaging surveillance for a considerable number of patients with pancreatic cysts. The aims of this study were to assess the accuracy of the AGA guidelines in detecting advanced neoplasia and present an alternative approach to pancreatic cysts.

METHODS

The study population consisted of 225 patients who underwent EUS-guided FNA for pancreatic cysts between January 2014 and May 2015. For each patient, clinical findings, EUS features, cytopathology results, carcinoembryonic antigen analysis, and molecular testing of pancreatic cyst fluid were reviewed. Molecular testing included the assessment of hotspot mutations and deletions for KRAS, GNAS, VHL, TP53, PIK3CA, and PTEN.

RESULTS

Diagnostic pathology results were available for 41 patients (18%), with 13 (6%) harboring advanced neoplasia. Among these cases, the AGA guidelines identified advanced neoplasia with 62% sensitivity, 79% specificity, 57% positive predictive value, and 82% negative predictive value. Moreover, the AGA guidelines missed 45% of intraductal papillary mucinous neoplasms with adenocarcinoma or high-grade dysplasia. For cases without confirmatory pathology, 27 of 184 patients (15%) with serous cystadenomas (SCAs) based on EUS findings and/or VHL alterations would continue magnetic resonance imaging (MRI) surveillance. In comparison, a novel algorithmic pathway using molecular testing of pancreatic cyst fluid detected advanced neoplasias with 100% sensitivity, 90% specificity, 79% positive predictive value, and 100% negative predictive value.

CONCLUSIONS

The AGA guidelines were inaccurate in detecting pancreatic cysts with advanced neoplasia. Furthermore, because the AGA guidelines manage all neoplastic cysts similarly, patients with SCAs will continue to undergo unnecessary MRI surveillance. The results of an alternative approach with integrative molecular testing are encouraging but require further validation.

Risk of pancreatic malignancy and mortality in branch-duct IPMNs undergoing surveillance: A systematic review and meta-analysis

BACKGROUND

Safety of non-operative management for low-risk branch-duct intraductal papillary mucinous neoplasms (BD-IPMNs) is debated.

AIM

To perform a systematic review/meta-analysis to determine their risk of developing pancreatic malignancy and of pancreatic malignancy-related deaths.

METHODS

A MEDLINE search was performed and methodology was based on PRISMA statement. Incidence rates of overall pancreatic malignancy, malignant BD-IPMN, IPMN-distinct PDAC, and of pancreatic malignancy-related death rates were calculated by dividing the total number of events by the total number of person-years (pyrs) of follow-up. Heterogeneity was determined by I(2) statistic.

RESULTS

20 studies including 2177 patients were included. Mean follow-up ranged from 29.3 to 76.7 months. Overall, 82 patients (3.7%) developed a pancreatic malignancy with a pooled estimate rate of 0.007/pyrs (I(2)=32.8%). The pooled estimate rate of malignant IPMN was 0.004/pyrs (I(2)=40.8%), and the pooled estimate rate of distinct PDAC 0.002/pyrs (I(2)=0%). The rate of death due to pancreatic malignancy during follow-up was 0.9%, with an overall pooled estimate rate of death of 0.002/pyrs (I(2)=0%).

CONCLUSION

Non-operative management of low-risk BD-IPMN is safe, with a very low risk of malignant transformation of IPMN and of distinct PDAC. The rate of pancreatic malignancy-related mortality is low, particularly when compared with the mortality of pancreatic surgery.

Distinguishing benign from malignant main duct intraductal papillary mucinous neoplasms of the pancreas by multislice helical computed tomography

Main duct intraductal papillary mucinous neoplasms (MD-IPMNs) of the pancreas are located in the dilated main pancreatic duct and associated with mucin overproduction. They may have a high degree of malignancy and lack specific clinical manifestations. With advantages of thin slice thickness, high resolution, multi-phase dynamic scan and multiple post-processing techniques, multislice helical computed tomography (MSCT) can accurately diagnose and differentiate malignant from benign MD-IPMNs. This paper will review the current advances in differentiating malignant from benign MD-IPMNs by MSCT.

International consensus on the management of intraductal papillary mucinous neoplasm of the pancreas

International consensus guidelines for the management of intraductal papillary mucinous neoplasm (IPMN) of the pancreas revised in 2012 (Fukuoka consensus) seem to be accepted well worldwide. Division of various factors to predict malignant transformation into two categories, i.e., "high-risk stigmata" and "worrisome features", is also accepted as practically useful for stratifying the risk factors. Our current interest resides in the development of noninvasive and/or invasive pancreatic cancer in areas of the pancreas distinct from IPMN. Invasive pancreatic cancers derived from and concomitant with IPMN should be distinguished to clarify the incidence of each entity, although some more definitive method for differentiation has to be devised in some cases where histological distinction is obscure. IPMN is a clue to early detection of pancreatic cancer. The optimal surveillance protocol for IPMN on observation should be determined in consideration of both of these different pancreatic cancers.

Imaging patterns of intraductal papillary mucinous neoplasms of the pancreas: an illustrated discussion of the International Consensus Guidelines for the Management of IPMN

Intraductal papillary mucinous neoplasms (IPMN) are being diagnosed with increasing frequency, necessitating an algorithm to help stratify patients into low- and high-risk groups, for follow-up versus more invasive evaluation. New evidence concerning their natural history and overall risk of malignancy has emerged since the 2006 International Association of Pancreatology consensus guidelines, prompting an update in 2012, that distinguishes radiologic 'worrisome features' from 'high-risk stigmata'. The aim of this article is to illustrate, with case examples, the variable imaging patterns of IPMN and how their radiologic features, such as cyst size and mural nodules, are interpreted in the context of the new 2012 guidelines. The 2012 and 2006 guidelines will be compared and discussed with reference to additional studies that have since been published. Despite these guidelines, lingering uncertainty remains about the natural history of IPMN, a source of unease to both radiologists and referring clinicians alike, mandating further refinement of clinical and radiologic parameters predictive of malignancy. Emerging data regarding the risk of extrapancreatic malignancy, as well as synchronous or metachronous pancreatic ductal adenocarcinoma remote in location from a branch duct IPMN are also reviewed. With the expanding research and evolving understanding of this clinicopathologic entity across the globe, radiologists will continue to play an important role in the management of patients with IPMN.

Sendai and Fukuoka Consensus Guidelines Identify Advanced Neoplasia in Patients With Suspected Mucinous Cystic Neoplasms of the Pancreas

BACKGROUND & AIMS

Little is known about whether the 2006 Sendai guidelines or 2012 Fukuoka guidelines are being used to determine the level of risk posed by suspected pancreatic mucinous cystic neoplasms (PCNs). We evaluated whether the guidelines accurately predicted which patients with suspected PCNs, which was based on cross-sectional imaging findings, would be found to have advanced neoplasia in surgery.

METHODS

We performed a retrospective study of data collected from 194 patients with cystic lesions of the pancreas, which were assessed by cross-sectional imaging analyses, who underwent surgery for suspected PCNs at the Hospital at the University of Pennsylvania from 2000 through 2008. Imaging data were used to classify patients according to the Sendai guidelines as high risk or low risk and according to the Fukuoka guidelines as high risk, worrisome, or low risk. Pathology analyses of samples collected during surgery were used as the reference. A logistic regression model was created to identify factors associated with advanced neoplasia. The Sendai and Fukuoka guideline criteria were analyzed by univariate and multivariable logistic regression analyses.

RESULTS

Advanced neoplasias were found in 36 patients (18.5%; 22 invasive cancers and 14 high-grade dysplasias). The median size of cysts was 33 mm. All patients found to have invasive cancers were accurately assigned to the Sendai guidelines high risk or Fukuoka guidelines high risk groups. However, 3 patients in the Sendai guidelines low risk and 2 patients in the Fukuoka guidelines low risk groups were found to have high-grade dysplasia. The Sendai guidelines identified patients with advanced neoplasia with 91.7% sensitivity, 21.5% specificity, 21% positive predictive value, and 91.9% negative predictive value. A designation of Fukuoka guidelines high risk identified patients with advanced neoplasia with 55.6% sensitivity, 73% specificity, 32% positive predictive value, and 87.9% negative predictive value. Overall, there was no statistically significant difference between the guidelines in predicting which patients had advanced neoplasia. On multivariate analysis, the presence of a mural nodule (odds ratio [OR], 2.88; 95% confidence interval [CI], 1.33-6.27; P = .008), dilated main pancreatic duct >10 mm (OR, 7.44; 95% CI, 2.36-23.52; P = .001), or enhancing solid component (OR, 2.92; 95% CI, 1.16-7.64; P = .02) were associated with detection of advanced neoplasia in pancreatic cysts.

CONCLUSION

On the basis of a retrospective analysis, the Sendai and Fukuoka guidelines accurately determine which patients with pancreatic cysts have advanced neoplasia. The guidelines accurately recommended surgical resection for all patients found to have invasive cancer, although some patients with high-grade dysplasia were missed. The updated Fukuoka guidelines are not superior to the Sendai guidelines in identifying neoplasias. Cyst size was not associated with advanced neoplasia.

Pancreatic Resection for Side-Branch Intraductal Papillary Mucinous Neoplasm (SB-IPMN): a Contemporary Single-Institution Experience

BACKGROUND

Given the malignant potential of main duct intraductal papillary mucinous neoplasm (M-IPMN), surgical resection is generally indicated. With regard to side-branch intraductal papillary mucinous neoplasm (SB-IPMN), resection vs. observation is a topic of debate. Further review of SB-IPMN is necessary to clarify appropriate management. The primary focus of this project is to determine the incidence of malignant final pathology for patients undergoing surgery for isolated SB-IPMN with non-malignant fine-needle aspiration (FNA) cytology. We also sought to describe the relationship between factors considered in the international consensus guidelines and final pathologic outcome.

METHODS

The study is a retrospective review of all patients who underwent surgical resection for intraductal papillary mucinous neoplasm (IPMN) from 2002 to 2013 at our institution. Patients with a preoperative diagnosis of isolated SB-IPMN and FNA results for non-malignant cytology were selected among this surgical cohort for further analysis of preoperative clinical characteristics and outcomes.

RESULTS

A total of 137 patients undergoing resection for IPMN were identified. Of these, 81 patients (59%) had a component of M-IPMN or invasive disease on FNA, leaving 66 (46%) patients with SB-IPMN and non-malignant cytology. Invasive adenocarcinoma was found in 8/66 (12%) patients and high-grade dysplasia (HGD) in 4/66 (8%) patients. The mean [SD] diameter of benign SB-IPMN was 2.0 cm [1.1] (range 0.3-5.7) vs. that of HGD/invasive disease which was 3.1 cm [1.3] (range 1.5-6.0; P = 0.014). Of the 12 patients found to have HGD or invasive disease, symptoms, mural nodules, and septations were found in 7 (58%), 5 (42%), and 6 (50%), respectively. Tumor staging were as follows: IA (2), IB (2), 2A (4), and 2B (1).

CONCLUSION

With proper selection criteria, SB-IPMN is associated with a low rate of invasive pancreatic ductal adenocarcinoma at the time of resection. Nevertheless, given the demonstrated incidence of malignancy, appropriate operative candidates should undergo resection.