Treatment guidelines for branch duct type intraductal papillary mucinous neoplasms of the pancreas: when can we operate or observe?

Optimization of Endoscopic Ultrasound Characteristics in the Diagnosis of Malignant Intraductal Papillary Mucinous Neoplasm

OBJECTIVES

Endoscopic ultrasound (EUS) is an excellent diagnostic tool that provides high-resolution images of pancreatic cystic lesions. However, its role in the diagnosis of malignant intraductal papillary mucinous neoplasm (IPMN) remains limited and unclear. We aimed to determine the usefulness of this modality for such diagnosis.

METHODS

Overall, 246 patients who underwent EUS for IPMN after computed tomography (CT)/magnetic resonance imaging (MRI) from April 2018 to June 2021 were followed up until March 2022. We assessed the added value of performing EUS after CT or MRI for diagnosing malignant IPMN, using receiver operating characteristic curve analysis. Walls as thick as 2 mm were considered thickened in this study if they were highly uneven.

RESULTS

EUS clearly enhanced accuracy in identifying enhancing nodules and thickened walls. The areas under the receiver operating characteristic curve and corresponding 95% confidence intervals were 0.655 (0.549-0.760) and 0.566 (0.478-0.654) upon CT/MRI but 0.853 (0.763-0.942) and 0.725 (0.634-0.817) when observed using EUS. The combination of nodule size, thickened wall, and main duct size yielded the highest area under the receiver operating characteristic curve (0.944 [0.915-0.973]).

CONCLUSIONS

EUS more accurately detects malignant IPMN, as uneven wall thickening and certain nodules cannot be identified with CT/MRI.

Hepatic Steatosis After Partial Pancreatectomy in a Cohort of Patients with Intraductal Papillary Mucinous Neoplasm

Background/Aims

Nonalcoholic fatty liver disease (NAFLD) has been observed in patients after partial pancreatectomy. Previous studies have been performed on oncologic patients who underwent partial pancreatectomy and received adjuvant chemotherapy. By studying a cohort of patients with intraductal papillary mucinous neoplasms (IPMNs) who did not receive chemotherapy, the authors investigate the isolated effect of partial pancreatectomy on the development of fatty liver.

Methods

A retrospective search for patients with pancreatic IPMNs who underwent partial pancreatectomy at an academic center from 2006 to 2014 identified 63 patients, including 42 who had pancreaticoduodenectomy (PD) and 21 who had distal pancreatectomy (DP). Fourteen patients with preoperative hepatic steatosis, diabetes, obesity, on steroid therapy, history of malignancy, or incomplete data were excluded. No patient received chemotherapy. Liver fat signal fraction (LFSF) was computed by the Dixon method using pre- and postoperative in- and out-of-phase MRI.

Results

Of the 49 patients included in the study, 29 (59%) underwent PD and 20 (41%) underwent DP. A total of 17 patients (34%) developed fatty liver after surgery. The entire cohort developed significant weight loss, 72.1 versus 69.4 kg (P < 0.01). Postoperatively, there was significant increase in LFSF, 1.3% versus 9.6% following PD (P < 0.01), and 2.1% versus 9.4% following DP (P = 0.01).

Conclusion

Partial pancreatectomy increases the risk of NAFLD independent of chemotherapy-induced hepatotoxicity. The underlying mechanism remains unclear and possibly related to pancreatic exocrine insufficiency and malnutrition.

Pancreatic Cysts: Radiology

This article reviews the types of pancreatic cysts encountered in Radiologic practice. It summarizes the malignancy risk of each of the following: serous cystadenoma, mucinous cystic tumor, intraductal papillary mucinous neoplasm main duct and side branch, and some miscellaneous cysts such as neuroendocrine tumor and solid pseudopapillary epithelial neoplasm. Specific reporting recommendations are given. The choice between radiology follow-up versus endoscopic analysis is discussed.

Comparison of Society Guidelines for the Management and Surveillance of Pancreatic Cysts: A Review

Importance

The identification of incidental pancreas cystic lesions (PCLs) has increased in recent decades with the expanded use and improved sensitivity of cross-sectional imaging. Because the overall risk of malignancy associated with PCLs is low, yet the relative morbidity of pancreatic surgery is high, evidence-based guidelines are necessary for appropriate surveillance and management. Therefore, this article provides a review of existing guidelines regarding surveillance and management of PCLs and highlights recent advances in the diagnostic evaluation of cysts and the postresection management of mucinous lesions.

Observations

There are 5 main guidelines related to the management of PCLs: the American Gastrointestinal Association (AGA) guidelines, the American College of Gastroenterology (ACG) guidelines, the American College of Radiology (ACR) recommendations, the European evidence-based guidelines, and the International Association of Pancreatology (IAP)/Fukuoka guidelines. These guidelines are based on retrospective studies that do not account or control for most tumor- and patient-specific factors. These guidelines also vary in scope, recommendations for surgical resection vs surveillance, as well as duration and type of follow-up.

Conclusions and Relevance

PCL guidelines should be viewed within the context of the data limitations on which they are based. PCL subtype-specific guidelines on surveillance and treatment are needed. In the future, the integration of cyst-specific genomic analysis, as well as evolutions in advanced diagnostic tools, such as cyst fluid next-generation sequencing and EUS-guided confocal laser endomicroscopy, may also better inform treatment guidelines. Owing to the current low-quality evidence on which many guidelines are based and the inherent morbidity of pancreas surgery, it is imperative that patients with PCLs are referred to institutions with advanced diagnostics and a multidisciplinary approach to patient surveillance and management.

Clinical Implication of Preoperative C-Reactive Protein/Albumin Ratio in Malignant Transformation of Intraductal Papillary Mucinous Neoplasm: A Propensity Score Analysis

Background: Inflammation-based scoring has been reported to be useful for predicting the recurrence and prognosis of various carcinomas. This study retrospectively investigated the relationship between inflammation-based score and intraductal papillary mucinous neoplasms (IPMNs). Methods: Between January 2013 and October 2018, we enrolled 417 consecutive patients with pancreatic tumors who received surgical resections at our hospital. The main outcome was the association between the preoperative inflammation-based score and their accuracy in predicting malignant transformation of IPMN. Results: Seventy six patients were eligible. Pathological findings indicated that 35 patients had low-grade dysplasia, 18 had high-grade dysplasia, and 23 had invasive carcinomas. As the C-reactive protein albumin ratio (CAR) was higher, malignant transformation of IPMNs also increased (p = 0.007). In comparing CAR^high and CAR^low using cutoff value, the results using a propensity score analysis showed that the CAR^high group predicted malignant transformation of IPMNs (odds ratio, 4.18; 95% confidence interval, 1.37–12.8; p = 0.01). In the CAR^high group, disease-free survival (DFS) was significantly shorter (p = 0.04). In the worrisome features, the AUC for the accuracy of malignant transformation with CAR^high was 0.84 when combining with the MPD findings. Conclusions: Preoperative CAR could be a predictive marker of malignant transformation of IPMNs.

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.

Management of pancreatic cysts and guidelines: what the gastroenterologist needs to know

The prevalence of pancreatic cysts has increased significantly over the last decade, partly secondary to increased quality and frequency of cross-sectional imaging. While the majority never progress to cancer, a small number will and need to be followed. The management of pancreatic cysts can be both confusing and intimidating due to the multiple guidelines with varying recommendations. Despite the differences in the specifics of the guidelines, they all agree on several high-risk features that should get the attention of any clinician when assessing a pancreatic cyst: presence of a mural nodule or solid component, dilation of the main pancreatic duct (or presence of main duct intraductal papillary mucinous neoplasm), pancreatic cyst size ⩾3–4 cm, or positive cytology on pancreatic cyst fluid aspiration. Other important criteria to consider include rapid cyst growth (⩾5 mm/year), elevated serum carbohydrate antigen 19-9 levels, new-onset diabetes mellitus, or acute pancreatitis thought to be related to the cystic lesion.

Imaging Features for Predicting High-Grade Dysplasia or Malignancy in Branch Duct Type Intraductal Papillary Mucinous Neoplasm of the Pancreas: A Systematic Review and Meta-Analysis

BACKGROUND

The consensus guidelines for branch-duct intraductal papillary mucinous neoplasm (BD-IPMN) of the pancreas are mostly based on imaging features. This study aimed to determine imaging features and their diagnostic accuracy for predicting high-grade dysplasia (HGD)/malignancy in BD-IPMN, including mixed type.

METHODS

The PubMed, Embase, and Cochrane databases were searched, and data were extracted from relevant studies. As the main diagnostic accuracy index, diagnostic odds ratios (DORs) of imaging features for diagnosing HGD/malignancy in BD-IPMNs were pooled using the random-effects model. A bivariate random-effects approach was used to construct summary receiver operating characteristic curves for sensitivity and specificity estimation.

RESULTS

The pooled DOR was the highest for the enhanced solid component/mural nodule (MN) (DOR, 12.21; 95 % confidence interval [CI], 6.14-24.27), followed by a main pancreatic duct (MPD) diameter of 10 mm or greater (DOR, 7.93; 95 % CI, 3.02-20.83), solid component (DOR, 4.85; 95 % CI, 2.49-9.42), lymphadenopathy (DOR, 4.84; 95 % CI, 1.11-21.06), MN (DOR, 4.48; 95 % CI, 3.15-6.39), an MPD diameter of 5 mm or greater (DOR, 3.69; 95 % CI, 2.62-5.19), abrupt change in MPD caliber with distal pancreatic atrophy (DOR, 2.65; 95 % CI, 1.66-4.24), thickened/enhancing walls (DOR, 2.38; 95 % CI, 1.57-3.60), and cyst size of 3 cm or larger (DOR, 1.98; 95 % CI, 1.48-2.64). The largest area under the curve (0.89 and 0.95, respectively) and high specificity (0.95 and 0.98, respectively) also were found for enhanced solid component/MN and an MPD diameter of 10 mm or greater, albeit with low sensitivity (0.38 and 0.14, respectively).

CONCLUSIONS

The aforementioned imaging features could aid in predicting HGD/malignancy of BD-IPMN. Furthermore, enhanced solid component/MN and an MPD diameter of 10 mm or greater were the most important predictors of HGD/malignancy in BD-IPMN and should be considered as indications for surgery.

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.

Clinical and radiological features that predict malignant transformation in cystic lesions of the pancreas: a retrospective case note review

Background: Pancreatic cystic lesions (PCL) are being detected with increasing frequency. Current methods of stratifying risk of malignant transformation are imperfect. This study aimed to determine the frequency of pancreatic malignancy in patients with PCL and define clinical and radiological features that predict malignant transformation in patients managed by surgery and/or surveillance.

Methods: A retrospective cohort of adults who were evaluated in a tertiary hepatopancreaticobiliary centre between January 2000 - December 2013 with a confirmed PCL and followed up for at least 5 years. All cystic lesions were discussed at a weekly multidisciplinary meeting.

Results: Of the 1,090 patients diagnosed with a PCL, 768 patients were included in the study: 141 patients were referred for immediate pancreatic resection, 570 entered surveillance while 57 had a malignant PCL which was unresectable at diagnosis (n=47) or were unfit for surgery (n=10). In those who were resected following presentation, malignancy was present in 38%. During follow-up 2% of those entering a surveillance programme underwent malignant transformation. Clinical and radiological features associated with a high-risk PCL included older age, symptoms, associated solid component or dilated main pancreatic duct. In intraductal papillary mucinous neoplasms, larger size was not a feature of malignant transformation (benign vs. malignant 30mm vs. 23mm; P= 0.012).

Conclusion: The sensitivity of standard diagnostic tests leading to immediate surgery for high-risk PCL (malignant or mucinous) was 92% but with a specificity of just 5%. Surveillance of PCL without high-risk features within a multidisciplinary meeting was associated with a low incidence of cancer development, supporting the use of worrisome clinical and radiological features in the initial stratification of PCL.

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.

Diagnosis and management of pancreatic cystic neoplasms: current evidence and guidelines

Pancreatic cystic neoplasms (PCN) are a heterogeneous group of pancreatic cysts that include intraductal papillary mucinous neoplasms, mucinous cystic neoplasms, serous cystic neoplasms and other rare cystic lesions, all with different biological behaviours and variable risk of progression to malignancy. As more pancreatic cysts are incidentally discovered on routine cross-sectional imaging, optimal surveillance for patients with PCN is becoming an increasingly common clinical problem, highlighting the need to balance cancer prevention with the risk of (surgical) overtreatment. This Review summarizes the latest developments in the diagnosis and management of PCN, including the quality of available evidence. Also discussed are the most important differences between the PCN guidelines from the American Gastroenterological Association, the International Association of Pancreatology and the European Study Group on Cystic Tumours of the Pancreas, including diagnostic and follow-up strategies and indications for surgery. Finally, new developments in the management of patients with PCN are addressed.

Clinical validation of the 2017 international consensus guidelines on intraductal papillary mucinous neoplasm of the pancreas

Purpose

The 2017 international consensus guidelines (ICG) for intraductal papillary mucinous neoplasm (IPMN) of the pancreas were recently released. Important changes included the addition of worrisome features such as elevated serum CA 19-9 and rapid cyst growth (>5 mm over 2 years). We aimed to clinically validate the 2017 ICG and compare the diagnostic performance between the 2017 and 2012 ICG.

Methods

This was a retrospective cohort study. During January 2000–January 2017, patients who underwent complete surgical resection and had pathologic confirmation of branch-duct or mixed-type IPMN were included. To evaluate diagnostic performance, the areas under the receiver operating curves (AUCs) were evaluated.

Results

A total of 448 patients were included. The presence of mural nodule (hazard ratio [HR], 9.12; 95% confidence interval [CI], 4.60–18.09; P = 0.001), main pancreatic duct dilatation (>5 mm) (HR, 5.32; 95% CI, 2.67–10.60; P = 0.001), thickened cystic wall (HR, 3.40; 95% CI, 1.51–7.63; P = 0.003), and elevated CA 19-9 level (>37 unit/mL) (HR, 5.25; 95% CI, 2.05–13.42; P = 0.001) were significantly associated with malignant IPMN. Malignant lesions showed a cyst growth rate >5 mm over 2 years more frequently than benign lesions (60.9% vs. 29.7%, P = 0.012). The AUC was higher for the 2017 ICG than the 2012 ICG (0.784 vs. 0.746).

Conclusion

The new 2017 ICG for IPMN is clinically valid, with a superior diagnostic performance to the 2012 ICG. The inclusion of elevated serum CA 19-9 level and cyst growth rate to the 2017 ICG is appropriate.

Early Detection of Pancreatic Cancer: Opportunities and Challenges

Most patients with pancreatic ductal adenocarcinoma (PDAC) present with symptomatic, surgically unresectable disease. Although the goal of early detection of PDAC is laudable and likely to result in significant improvement in overall survival, the relatively low prevalence of PDAC renders general population screening infeasible. The challenges of early detection include identification of at-risk individuals in the general population who would benefit from longitudinal surveillance programs and appropriate biomarker and imaging-based modalities used for PDAC surveillance in such cohorts. In recent years, various subgroups at higher-than-average risk for PDAC have been identified, including those with familial risk due to germline mutations, a history of pancreatitis, patients with mucinous pancreatic cysts, and elderly patients with new-onset diabetes. The last 2 categories are discussed at length in terms of the opportunities and challenges they present for PDAC early detection. We also discuss current and emerging imaging modalities that are critical to identifying early, potentially curable PDAC in high-risk cohorts on surveillance.

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.

The role of age in pancreatic intraductal papillary mucinous neoplasms of the pancreas: Same risk of death but different implications for management

BACKGROUND

Current guidelines do not address the role of age in the management of intraductal papillary mucinous neoplasms (IPMNs) of the pancreas.

AIM

To evaluate whether clinical features and risk for malignancy are affected by patient's age at diagnosis.

METHODS

In total, 2189 IPMNs, both surgically resected or surveilled, were dichotomized according to a 50-year-old cutoff and compared in terms of pathological features, cumulative risk of developing high-risk stigmata (HRS), overall survival (OS) and disease-specific survival (DSS).

RESULTS

Patients <50 years had more frequent abdominal pain (38.5 vs. 22.4%; p < 0.01) and acute pancreatitis (20.4 vs. 9.3%; p < 0.01) at presentation. Patients ≥50 years old had more multifocal IPMNs (50 vs. 36.9%; p < 0.01), HRS (8.5% vs. 4.3%; p = 0.04) and invasive IPMNs (26.6% vs. 17.3%; p = 0.03) when resected. Moreover, patients ≥50 years old had a significantly higher cumulative risk of developing HRS over time, and a significantly lower OS, but similar DSS when compared with those <50 years old.

CONCLUSIONS

IPMNs diagnosed in older patients are more likely to progress to HRS despite the fact that cancer-related death is not affected by age. The follow-up schedule should not be adjusted according to age, but one should take into account that IPMNs in younger individuals have more time to progress toward malignancy.

Management of Intraductal Papillary Mucinous Neoplasms: Controversies in Guidelines and Future Perspectives

Purpose of review

Management of intraductal papillary mucinous neoplasm (IPMN) is currently based on consensus, in the absence of evidence-based guidelines. In recent years, several consensus guidelines have been published, with distinct management strategies. In this review, we will discuss these discrepancies, in order to guide treating physicians in clinical management.

Recent findings

The detection rate of pancreatic cysts has increased substantially with the expanded use of high-quality imaging techniques to up to 45%. Of these cysts, 24–82% are IPMNs, which harbour a malignant potential. Timely detection of high-risk lesions is therefore of great importance. Surgical management is based on the presence of clinical and morphological high-risk features, yet the majority of resected specimens appear to be low risk.

Summary

International collaboration and incentive large-scale prospective registries of individuals undergoing cyst surveillance are needed to accumulate unbiased data and develop evidence-based guidelines. Additionally, development of non-invasive, accurate diagnostic tools (e.g. biomarkers) is needed to differentiate between neoplastic and non-neoplastic pancreatic cysts and detect malignant transformation at an early stage (i.e. high-grade dysplasia).

Intraductal Papillary Mucinous Neoplasm of the Pancreas as the Main Focus for Early Detection of Pancreatic Adenocarcinoma

For early detection of pancreatic cancer, interests are now focused on the detection of high-risk individuals to undergo screening examinations. Intraductal papillary mucinous neoplasm (IPMN) is a unique dual precursor of pancreatic cancer, characterized by progression to invasive cancer and the development of pancreatic adenocarcinoma either concomitantly (synchronous occurrence) or even after resection of IPMN (metachronous occurrence). Careful examination and surveillance of patients with IPMN may therefore lead to early detection of pancreatic cancer. By reviewing only reports describing detailed breakdown of the morphological types of IPMN and numbers of patients with noninvasive and invasive carcinoma in each type, the rough frequencies of noninvasive carcinoma in main duct IPMNs and branch duct IPMNs (BD-IPMNs) are 20% and 10%, respectively, and those of invasive carcinoma are 40% and 13%, respectively. Roughly 5% of all patients with IPMN had concomitant adenocarcinoma. The real frequency of carcinoma in BD-IPMNs would be far lower because most patients with small asymptomatic BD-IPMNs do not undergo resection. Intraductal papillary mucinous neoplasm can be the main focus for early detection of pancreatic cancer to achieve favorable prognosis after surgical resection. The optimal protocol for surveillance and method for early detection of pancreatic cancer are to be determined.

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.

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

Background

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

Methods

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

Results

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

Conclusion

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

Experience-based surgical approach to pancreatic mucinous cystic neoplasms with ovarian-type stroma

The present study aimed to elucidate the clinicopathological characteristics of resected mucinous cystic neoplasm (MCN) with ovarian-type stroma and identify a surgical approach for MCN treatment, on the basis of Republic of Korean (Yonsei University College of Medicine, Seoul, South Korea) and Japanese (Nippon Medical School, Tokyo, Japan) bi-institutional collaboration. The present study retrospectively reviewed 55 MCNs with ovarian-type stroma using pathological re-examination. Clinicopathological features and preoperative clinical parameters were evaluated to predict malignant alterations in MCNs. The proportion of surgically treated MCNs has recently been increasing. All patients included in the present study were female, with a mean age of 47.9±13.3 years. Mural nodules were noted in 8 patients (14.5%) and the mean cyst size was 6.1±4.2 cm. A total of 9 patients (16.4%) were identified to exhibit non-invasive mucinous cystadenocarcinoma. The number of patients with small tumors (R²=-0.079, P=0.038) and asymptomatic pancreatic MCNs (P=0.022) was significantly increased (P<0.05), which resulted in the more frequent application of minimally invasive surgery (P<0.001). During the follow-up period (mean, 51.6 months; range, 1.1-242.8 months), no recurrence or tumor-associated mortality was identified. The presence of mural nodules (P=0.002) and a tumor size ≥4.5 cm (P=0.027) were identified as potential clinical parameters for predicting malignant transformation. The significance of mural nodules in predicting malignant transformation was increased in large MCNs (≥4.5 cm) of the pancreas compared with small MCNs (<4.5 cm) (P=0.002). Overall, non-invasive pancreatic MCNs are not aggressive, and minimally invasive pancreatectomy may be an effective approach for suitable patients.

Impact of MUC1 Expression on the Progression of Intraductal Papillary Mucinous Neoplasm With Worrisome Features During Follow-up

OBJECTIVES

The aim of this study was to investigate whether MUC1 expression is associated with progression of intraductal papillary mucinous neoplasms with worrisome features during follow-up.

METHODS

Fifteen patients positive for MUC1 and negative for MUC2 (MUC1 group) and 16 patients negative for MUC1 and MUC2 (control group) were followed up and examined for changes in diameters of the main and ectatic branches of pancreatic ducts, enlargement of mural nodules, and appearance of a solid mass, by imaging studies. All of them presented worrisome features, and none had "high-risk stigmata."

RESULTS

The sizes of the main and ectatic branches of pancreatic ducts increased in 8 (53.3%) and 8 (53.3%) patients, respectively, of the MUC1 group and in 1 (6.3%) and 1 (6.3%) patients, respectively, of the control group (P = 0.0059 and 0.0059, respectively). A solid mass developed in 6 patients (33.3%) of the MUC1 group but in none of the control group patients (P = 0.0373).

CONCLUSIONS

Positive MUC1 expression in cell block cytology specimens may be associated with progressive dilation of the main and ectatic branches of pancreatic ducts and appearance of a solid mass in patients with intraductal papillary mucinous neoplasm with worrisome features during follow-up.

[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.

Validation of the 2012 Fukuoka Consensus Guideline for Intraductal Papillary Mucinous Neoplasm of the Pancreas From a Single Institution Experience

OBJECTIVES

The 2012 Fukuoka consensus guideline has stratified the risks of malignant intraductal papillary mucinous neoplasm (IPMN) of the pancreas into "high-risk stigmata" (HRS) and "worrisome feature" (WF). This study aimed to evaluate its clinical validity based on a single institution experience.

METHODS

Eighty-nine patients who underwent surgical resection with pathological diagnosis of IPMN were retrospectively studied.

RESULTS

High-risk stigmata was significantly correlated with the prevalence of malignant IPMN as compared with WF. The positive predictive values of HRS and WF were 66.7% and 35.7% for branch duct IPMN and 80% and 38.1% for main duct IPMN, respectively. Univariate analysis indicated that all the factors in HRS and WF had statistical significance. Whereas multivariate analysis revealed only enhanced solid component (odds ratio [OR], 50.01; P = 0.008), presence of mural nodule (OR, 73.83; P < 0.001) and lymphadenopathy (OR, 20.85; P = 0.03) were independent predictors. Scoring HRS and WF by different numbers of positive factors resulted in improved predictive value. The area under the curve of HRS score was significantly lower than that of WF or HRS + WF score (0.680 vs 0.900 or 0.902, respectively; P < 0.001).

CONCLUSIONS

As supplementary to the 2012 Fukuoka guideline, we suggest that calculating scores of WF and HRS may have superior diagnostic accuracy in predicting malignant IPMN.

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.

Natural History of Pancreatic Cysts

Pancreatic cystic neoplasms are discovered with increasing frequency. Accurate knowledge of the natural history of cystic neoplasms is crucial to develop useful and cost-effective strategies for surveillance and surgical resection. To date, the natural history of cystic neoplasms is still incomplete due to lack of adequate diagnostic accuracy in the absence of surgical pathology. Nevertheless, current evidence points to risk factors for malignant transformation to help clinical management. New biomarkers that accurately distinguish cyst neoplasms and those most likely to progress to cancer would help clarify the natural history of cystic neoplasms.

Management of Incidental Pancreatic Cysts: A White Paper of the ACR Incidental Findings Committee

The ACR Incidental Findings Committee (IFC) presents recommendations for managing pancreatic cysts that are incidentally detected on CT or MRI. These recommendations represent an update from the pancreatic component of the JACR 2010 white paper on managing incidental findings in the adrenal glands, kidneys, liver, and pancreas. The Pancreas Subcommittee-which included abdominal radiologists, a gastroenterologist, and a pancreatic surgeon-developed this algorithm. The recommendations draw from published evidence and expert opinion, and were finalized by informal iterative consensus. Algorithm branches successively categorize pancreatic cysts based on patient characteristics and imaging features. They terminate with an ascertainment of benignity and/or indolence (sufficient to discontinue follow-up), or a management recommendation. The algorithm addresses most, but not all, pathologies and clinical scenarios. Our goal is to improve quality of care by providing guidance on how to manage incidentally detected pancreatic cysts.

Cystic pancreatic lesions: From increased diagnosis rate to new dilemmas

Cystic pancreatic lesions vary from benign to malignant entities and are increasingly detected on cross-sectional imaging. Knowledge of the imaging appearances of cystic pancreatic lesions may help radiologists in their diagnostic reporting and management. In this review, we discuss the morphologic classification of these lesions based on a diagnostic algorithm as well as the management of these lesions.

Outcome of long interval radiological surveillance of side branch pancreatic duct-involved intraductal papillary mucinous neoplasm in selected patients

INTRODUCTION

Side branch IPMN (SB-IPMN) of the pancreas has a malignancy rate between 10 and 20%. We hypothesized that surveillance at longer intervals on selected patients with SB-IPMN might be indicated.

METHODS

This is a retrospective study of prospectively collected data of 276 patients presenting from 2000 to 2010. After 2007, we opted to screen our patients with longer intervals, initially at 12 months then 24 months using MR if no "worrisome features" were present.

RESULTS

Complete data sets for 261 patients were analysed and patients were aged 78 (40-91) years. 232 patients had sole SB-IPMN while 92% were incidental (n = 209) and 8% were symptomatic (n = 24). Single SB-IPMN accounted for 84% (n = 195) of all cases; maximum diameter of 15.5 (5-60) mm. The median follow up duration was 46 (32-53) months. Short interval radiological surveillance (3-9 months) was 39% (n = 90), while long interval surveillance (12-36 months) was performed in 61% (n = 142). The rate of pancreatic resection, due to concern for the development of pancreatic cancer, in the short and long interval surveillance groups was 4.4% (n = 4) and 3.5% (n = 5) respectively; p = 0.78.

CONCLUSION

Our data suggests no difference in outcome between long and short interval MR surveillance of SB-IPMN patients.

Validation of the 2012 International Consensus Guidelines Using Computed Tomography and Magnetic Resonance Imaging: Branch Duct and Main Duct Intraductal Papillary Mucinous Neoplasms of the Pancreas

OBJECTIVE

To validate the 2012 guidelines for intraductal papillary mucinous neoplasm (IPMN) of the pancreas and to compare diagnostic performances of computed tomography (CT) and magnetic resonance imaging (MRI) for differentiating malignant from benign IPMN.

BACKGROUND

As IPMN has variable risks of malignancy and management of this entity is closely related to its malignant potential, it is important to predict risks of IPMN malignancy.

METHODS

This retrospective study included 158 patients with surgically confirmed IPMN of the pancreas who underwent both preoperative CT and MRI. Two radiologists evaluated the "high-risk stigmata" and "worrisome features" of the 2012 guidelines for branch duct (BD)-IPMN and main duct (MD)-IPMN. Univariate and multivariable analyses were used to identify significant predictors of malignancy in IPMN. The diagnostic performance was compared between CT and MRI.

RESULTS

Malignant IPMN was seen in 8 of 60 patients (13.3%) with BD-IPMN and 44 of 98 patients (44.9%) with MD-IPMN. Presence of mural nodule was the most important predictor in BD-IPMN and MD-IPMN (odds ratios, 9.2 and 7.6, respectively, P = 0.01 on CT; and odds ratios, 5.7 and 13.3, respectively, P ≤ 0.04 on MRI), whereas mural nodule size and lymphadenopathy were significant only in MD-IPMN (P < 0.05). The diagnostic performance of CT and MRI for significant findings was not statistically different in both types of IPMN (P > 0.34).

CONCLUSIONS

The presence of mural nodule was the most important predictor of malignancy in both types of IPMN. Mural nodule size and lymphadenopathy were also significant predictors in MD-IPMN. Computed tomography and MRI showed similar diagnostic performances for differentiating malignant from benign IPMN.

Validation of international consensus guideline 2012 for intraductal papillary mucinous neoplasm of pancreas

Purpose

Intraductal papillary mucinous neoplasm (IPMN) has variable malignant potential ranging from premalignant intraductal lesions to malignant neoplasms with invasive carcinoma. To help physicians managing patients with IPMN, International consensus guidelines was made in 2006 and revised in 2012. This study was designed to evaluate the clinical usefulness of guidelines and to validate.

Methods

From October 1996 to December 2011, we retrospectively reviewed the data of 230 patients who underwent pancreatic resection for IPMN. Univariate and multivariable analyses were used to identify significant predictors of malignancy in IPMN.

Results

Of the 230 patients, 62 patients (27%) were diagnosed with invasive carcinoma. Jaundice (P < 0.001; 95% confidence interval [CI], 3.086–40.010) main pancreatic duct diameter equal to or greater than 10 mm (P < 0.001; 95% CI, 1.723–6.673) and also abdominal pain (P < 0.001; 95% CI, 4.363–22.600) show statistical significance in univariate and multivariate analysis. "High-risk stigmata" was statistical powerful predictors of malignancy than "worrisome features". International consensus guidelines 2012 had improvement on specificity but deterioration of sensitivity.

Conclusion

Revised guidelines seemed to bring about an improvement of weak side of Sendai criteria. Abdominal pain, jaundice, main pancreas duct greater than 10 mm can be clinical variables to predict malignancy.

Pathologic Evaluation and Reporting of Intraductal Papillary Mucinous Neoplasms of the Pancreas and Other Tumoral Intraepithelial Neoplasms of Pancreatobiliary Tract: Recommendations of Verona Consensus Meeting

BACKGROUND

There are no established guidelines for pathologic diagnosis/reporting of intraductal papillary mucinous neoplasms (IPMNs).

DESIGN

An international multidisciplinary group, brought together by the Verona Pancreas Group in Italy-2013, was tasked to devise recommendations.

RESULTS

(1) Crucial to rule out invasive carcinoma with extensive (if not complete) sampling. (2) Invasive component is to be documented in a full synoptic report including its size, type, grade, and stage. (3) The term "minimally invasive" should be avoided; instead, invasion size with stage and substaging of T1 (1a, b, c; ≤ 0.5, > 0.5-≤ 1, > 1 cm) is to be documented. (4) Largest diameter of the invasion, not the distance from the nearest duct, is to be used. (5) A category of "indeterminate/(suspicious) for invasion" is acceptable for rare cases. (6) The term "malignant" IPMN should be avoided. (7) The highest grade of dysplasia in the non-invasive component is to be documented separately. (8) Lesion size is to be correlated with imaging findings in cysts with rupture. (9) The main duct diameter and, if possible, its involvement are to be documented; however, it is not required to provide main versus branch duct classification in the resected tumor. (10) Subtyping as gastric/intestinal/pancreatobiliary/oncocytic/mixed is of value. (11) Frozen section is to be performed highly selectively, with appreciation of its shortcomings. (12) These principles also apply to other similar tumoral intraepithelial neoplasms (mucinous cystic neoplasms, intra-ampullary, and intra-biliary/cholecystic).

CONCLUSIONS

These recommendations will ensure proper communication of salient tumor characteristics to the management teams, accurate comparison of data between analyses, and development of more effective management algorithms.

What Is the Best Way to Identify Malignant Transformation Within Pancreatic IPMN: A Systematic Review and Meta-Analyses

OBJECTIVES

Pancreatic intraductal papillary mucinous neoplasias (IPMNs) represent 25% of all cystic neoplasms and are precursor lesions for pancreatic ductal adenocarcinoma. This study aims to identify the best imaging modality for detecting malignant transformation in IPMN, the sensitivity and specificity of risk features on imaging, and the usefulness of tumor markers in serum and cyst fluid to predict malignancy in IPMN.

METHODS

Databases were searched from November 2006 to March 2014. Pooled sensitivity and specificity of diagnostic techniques/imaging features of suspected malignancy in IPMN using a hierarchical summary receiver operator characteristic (HSROC) approach were performed.

RESULTS

A total of 467 eligible studies were identified, of which 51 studies met the inclusion criteria and 37 of these were incorporated into meta-analyses. The pooled sensitivity and specificity for risk features predictive of malignancy on computed tomography/magnetic resonance imaging were 0.809 and 0.762 respectively, and on positron emission tomography were 0.968 and 0.911. Mural nodule, cyst size, and main pancreatic duct dilation found on imaging had pooled sensitivity for prediction of malignancy of 0.690, 0.682, and 0.614, respectively, and specificity of 0.798, 0.574, and 0.687. Raised serum carbohydrate antigen 19-9 (CA19-9) levels yielded sensitivity of 0.380 and specificity of 0903. Combining parameters yielded a sensitivity of 0.743 and specificity of 0.906.

CONCLUSIONS

PET holds the most promise in identifying malignant transformation within an IPMN. Combining parameters increases sensitivity and specificity; the presence of mural nodule on imaging was the most sensitive whereas raised serum CA19-9 (>37 KU/l) was the most specific feature predictive of malignancy in IPMNs.

Comparison of the international consensus guidelines for predicting malignancy in intraductal papillary mucinous neoplasms

BACKGROUND

This study sought to evaluate the predictors of malignancy in the 2012 international consensus guidelines for intraductal papillary mucinous neoplasms (IPMNs) and validate their diagnostic value relative to the 2006 guidelines.

METHODS

Between 2002 and 2014, 177 consecutive patients who underwent curative resection of IPMN were reviewed. Based on the 2012 guidelines, high-risk stigmata (mural nodule with enhancement, main pancreatic duct [MPD] ≥ 10 mm, and obstructive jaundice) and worrisome features (cyst size ≥ 30 mm, thickened cyst wall, mural nodule without enhancement, MPD 5-9 mm, an abrupt change in MPD diameter, and lymphadenopathy) were assessed, and predictive and diagnostic values were analyzed statistically.

RESULTS

Multivariate analysis identified obstructive jaundice (odds ratio [OR], 23.9; P < .0001), abrupt change in MPD diameter (OR, 3.01; P = .017) and lymphadenopathy (OR, 5.84; P = .027) as independent predictive factors, with an accuracy of 69.8, 67.4, and 66.3%, respectively. Operative intervention was indicated in 156 patients (94.0%) using the 2006 guidelines, and in 130 (78.3%) using the 2012 guidelines. The accuracy of the 2006 guidelines was 35.5% compared with 44.8% for the 2012 guidelines. The area under the curve (AUC) for the 2006 and 2012 guidelines was 0.65 and 0.67, respectively; ΔAUC was 0.02, which was not statistically significant. When the worrisome features were combined with high-risk stigmata, the AUC increased to 0.79.

CONCLUSION

Obstructive jaundice, abrupt change in MPD diameter, and lymphadenopathy were independent predictive factors in the 2012 guidelines with high accuracy. Using the new guidelines, the number of patients with IPMN managed with observation and the predictive accuracy increased.

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.

Main- and Branch-Duct Intraductal Papillary Mucinous Neoplasms: Extent of Surgical Resection

Background

Surgical treatment of intraductal papillary mucinous neoplasms (IPMN) requires a differentiated approach regarding indications and extent of resection.

Methods

The review summarizes the current literature on indication, timing, and surgical procedures in IPMN.

Results

The most important differentiation has to be made between main-duct and branch-duct IPMN as well as mixed-type lesions that biologically mimic main-duct types. In main-duct and mixed-type IPMN, the resection should be indicated by the time of the diagnosis – in accordance with the international consensus guidelines – and should follow oncological principles. Depending on IPMN localization, this implies partial pancreatoduodenectomy, distal pancreatectomy, or total pancreatectomy and includes the corresponding types of lymphadenectomy. Furthermore, branch-duct IPMN > 3 cm or bearing high-risk features (mural nodules in magnetic resonance imaging, computed tomography, or endoscopic ultrasound imaging; symptomatic lesions; elevated tumor markers) are similarly treated. As the risk for malignancy in smaller branch-duct IPMN is lower, the decision for surgical treatment is often individually made – despite the updated 2012 guidelines. In these lesions, limited surgical approaches, including enucleation and central pancreatectomy, are possible.

Conclusion

Timely and radical resection of IPMN offers the unique opportunity to prevent pancreatic cancer, and even in malignant IPMN surgery can offer a curative approach with excellent long-term outcome in early stages. A structured imaging follow-up should be considered to recognize IPMN recurrence and metachronous pancreatic cancer as well as gastrointestinal neoplasias by endoscopic surveillance.

Natural History and Management of Intraductal Papillary Mucinous Neoplasms: Current Evidence

Background

With the use of modern cross-sectional abdominal imaging modalities, an increasing number of cystic pancreatic lesions are identified incidentally. Although there is no pathological diagnosis available in most cases, it is believed that the majority of these lesions display small branch-duct intraductal papillary mucinous neoplasms (BD-IPMNs) of the pancreas. Even though a number of large clinical series have been published, many uncertainties remain with regard to this entity of mucinous cystic neoplasms.

Methods

Systematic literature review.

Results

Main-duct (MD) and mixed-type IPMNs harbor a high risk of malignant transformation. It is conceivable that most IPMNs with involvement of the main duct tend to progress to invasive carcinoma over time. Thus, formal oncologic resection is the treatment of choice in surgically fit patients. In contrast, the data regarding BD-IPMN remain equivocal, resulting in conflicting concepts. To date, it is not clear whether and which BD-IPMNs progress to carcinoma and how long this progression takes.

Conclusion

While patients with MD-IPMNs should undergo surgical resection if comorbidities and life expectancy permit this, the management of small BD-IPMNs remains controversial. Population-based studies with long-term follow-up are needed to define which cohort of patients can be observed safely without immediate resection.

Laparoscopic Hand-Assisted Parenchymal-Sparing Resections for Presumed Side-Branch Intraductal Papillary Mucinous Neoplasms

BACKGROUND

The diagnosis of side-branch intraductal papillary mucinous neoplasms (IMPNs) is increasingly more common, but their appropriate management is still evolving. We recently began performing laparoscopic hand-assisted enucleation or duodenal-sparing pancreatic head resection for these lesions with vigilant postoperative imaging.

MATERIALS AND METHODS

Seventeen patients with pancreatic cystic lesions were included in this single-center retrospective review from January 1, 2008 to March 30, 2013. Indication for surgical intervention was growth in size of the cyst, symptoms, cyst size >3 cm, and/or presence of a mural nodule. Twelve patients underwent laparoscopic hand-assisted enucleation, and 5 patients underwent laparoscopic hand-assisted pancreatic head resection.

RESULTS

The mean age of patients was 64 years old. The most common presenting symptom was abdominal pain. The indication for surgical intervention was growth in the cyst or symptoms in the majority of patients. Fourteen lesions were in the head/uncinate, two were in the pancreatic body, and one was in the tail. Final pathology was consistent with side-branch IPMN in 13 patients (1 with focal adenocarcinoma). Three patients had serous cysts, and 1 had a mucinous cyst. Three patients developed pancreatic leaks, which were controlled with intraoperative placed drains, whereas 1 patient required additional drain placement. Median time from surgery to latest follow-up imaging is over 2 years. No patients have developed recurrent cysts or adenocarcinoma.

CONCLUSIONS

Duodenal-sparing pancreatic head resection or pancreatic enucleation for patients with presumed side-branch IPMN is a safe and efficacious option, in terms of both operative outcomes and postoperative recurrence risk.

Intraductal Papillary Mucinous Neoplasm of Pancreas

Intraductal papillary mucinous neoplasms (IPMNs) of the pancreas are neoplasms that are characterized by ductal dilation, intraductal papillary growth, and thick mucus secretion. This relatively recently defined pathology is evolving in terms of its etiopathogenesis, clinical features, diagnosis, management, and treatment guidelines. A PubMed database search was performed. All the relevant abstracts in English language were reviewed and the articles in which cases of IPMN could be identified were further scrutinized. Information of IPMN was derived, and duplication of information in several articles and those with areas of persisting uncertainties were excluded. The recent consensus guidelines were examined. The reported incidence of malignancy varies from 57% to 92% in the main duct-IPMN (MD-IPMN) and from 6% to 46% in the branch duct-IPMN (BD-IPMN). The features of high-risk malignant lesions that raise concern include obstructive jaundice in a patient with a cystic lesion in the pancreatic head, the findings on radiological imaging of a mass lesion of >30 mm, enhanced solid component, and the main pancreatic duct (MPD) of size ≥10 mm; while duct size 5-9 mm and cyst size <3 mm are considered as “worrisome features.” Magnetic resonance imaging (MRI) and endoscopic ultrasound (EUS) are primary investigations in diagnosing and following up on these patients. The role of pancreatoscopy and the analysis of aspirated cystic fluid for cytology and DNA analysis is still to be established. In general, resection is recommended for most MD-IPMN, mixed variant, and symptomatic BD-IPMN. The 5-year survival of patients after surgical resection for noninvasive IPMN is reported to be at 77-100%, while for those with invasive carcinoma, it is significantly lower at 27-60%. The follow-up of these patients could vary from 6 months to 1 year and would depend on the risk stratification for invasive malignancy and the pathology of the resected specimen. The understanding of IPMN has evolved over the years. The recent guidelines have played a role in this regard.

Quality assessment of the guidelines on cystic neoplasms of the pancreas

BACKGROUND

Though cystic pancreatic neoplasms (CPNs) are being increasingly detected, their evaluation and management are still debated and have lead to publication of multiple guidelines for diagnostic work-up, indications for resection, and non-operative management with follow-up strategies of CPNs.

AIMS

To analyze available guidelines in order to evaluate their overall quality and clinical applicability, indications for surgical resection and its extent, modalities and timing of follow-up when non-operative management is indicated.

METHODS

After a systematic search of the English literature, we selected eight guidelines for assessment according to the Appraisal of Guidelines, Research and Evaluation in Europe (AGREE) II instrument.

RESULTS

One guideline received the lower AGREE score regarding the "scope and purpose", "rigor of development" and "clarity and presentation" domains, whereas one received the best score for "stakeholder involvement" domain. No differences were found among different guidelines regarding the "applicability". The overall quality assessment score showed that only two guidelines were significantly lower than the others. According to the practical utilization recommendation score, four guidelines were considered as having full applicability in clinical practice.

CONCLUSION

Existing guidelines provide adequate guidance, at least with the present knowledge, for the management of cystic pancreatic lesions; however, not any one was satisfactory to all aspects related to the management of CPN. An update of the existing guidelines should be considered if and when more evidence-based data are available.