Development of ductal carcinoma of the pancreas during follow-up of branch duct intraductal papillary mucinous neoplasm of the pancreas

Selective epigenetic alterations in RNF43 in pancreatic exocrine cells from high-fat-diet-induced obese mice; implications for pancreatic cancer

OBJECTIVE

Pancreatic cancer (PC) originates and progresses with genetic mutations in various oncogenes and suppressor genes, notably KRAS, CDKN2A, TP53, and SMAD4, prevalent across diverse PC cells. In addition to genetic mutations/deletions, persistent exposure to high-risk factors, including obesity, induces whole-genome scale epigenetic alterations contributing to malignancy. However, the impact of obesity on DNA methylation in the presymptomatic stage, particularly in genes prone to PC mutation, remains uncharacterized.

RESULTS

We analyzed the methylation levels of 197 loci in six genes (KRAS, CDKN2A, TP53, SMAD4, GNAS and RNF43) using Illumina Mouse Methylation BeadChip array (280 K) data from pancreatic exocrine cells obtained from high-fat-diet (HFD) induced obese mice. Results revealed no significant differences in methylation levels in loci between HFD- and normal-fat-diet (NFD)-fed mice, except for RNF43, a negative regulator of Wnt signaling, which showed hypermethylation in three loci. These findings indicate that, in mouse pancreatic exocrine cells, high-fat dietary obesity induced aberrant DNA methylation in RNF43 but not in other frequently mutated PC-related genes.

Early features of pancreatic cancer on magnetic resonance imaging (MRI): a case-control study

PURPOSE

Magnetic resonance imaging has been recommended as a primary imaging modality among high-risk individuals undergoing screening for pancreatic cancer. We aimed to delineate potential precursor lesions for pancreatic cancer on MR imaging.

METHODS

We conducted a case-control study at Kaiser Permanente Southern California (2008-2018) among patients that developed pancreatic cancer who had pre-diagnostic MRI examinations obtained 2-36 months prior to cancer diagnosis (cases) matched 1:2 by age, gender, race/ethnicity, contrast status and year of scan (controls). Patients with history of acute/chronic pancreatitis or prior pancreatic surgery were excluded. Images underwent blind review with assessment of a priori defined series of parenchymal and ductal features. We performed logistic regression to assess the associations between individual factors and pancreatic cancer. We further assessed the interaction among features as well as performed a sensitivity analysis stratifying based on specific time-windows (2-3 months, 4-12 months, 13-36 months prior to cancer diagnosis).

RESULTS

We identified 141 cases (37.9% stage I-II, 2.1% III, 31.4% IV, 28.6% unknown) and 292 matched controls. A solid mass was noted in 24 (17%) of the pre-diagnostic MRI scans. Compared to controls, pre-diagnostic images from cancer cases more frequently exhibited the following ductal findings: main duct dilatation (51.4% vs 14.3%, OR [95% CI]: 7.75 [4.19-15.44], focal pancreatic duct stricture with distal (upstream) dilatation (43.6% vs 5.6%, OR 12.71 [6.02-30.89], irregularity (42.1% vs 6.0%, OR 9.73 [4.91-21.43]), focal pancreatic side branch dilation (13.6% vs1.6%, OR 11.57 [3.38-61.32]) as well as parenchymal features: atrophy (57.9% vs 27.4%, OR 46.4 [2.71-8.28], focal area of signal abnormality (39.3% vs 4.8%, OR 15.69 [6.72-44,78]), all p < 0.001).

CONCLUSION

In addition to potential missed lesions, we have identified a series of ductal and parenchymal features on MRI that are associated with increased odds of developing pancreatic cancer.

Pancreatic Cysts Greater Than 1 cm Are Associated With an Increased Risk for Developing Pancreatic Cancer in Individuals From Pancreatic-Cancer Prone Kindreds Undergoing Surveillance

BACKGROUND

The International Cancer of the Pancreas Screening Consortium recommended annual imaging for individuals at increased risk for developing a pancreatic ductal adenocarcinoma (PDAC) who did not have concerning pancreatic findings or a cyst <3 cm without worrisome features. We aimed to determine if 3-cm cyst size accurately predicted advanced precursor lesions in high-risk individuals undergoing surveillance.

METHODS

Imaging for high-risk individuals (HRIs) undergoing PDAC surveillance from 2007 to 2021 was reviewed and pancreatic abnormalities were recorded including dominant cyst size and number of cysts. Subjects were excluded if they had the following: (1) no follow-up imaging after baseline, (2) solid lesion at baseline, or (3) development of solid lesion without having cyst on prior imaging.

RESULTS

Five of the 77 HRIs found to have a cystic lesion on surveillance developed a PDAC: 3 with cystic lesion >1 cm as compared with only 2 of 67 HRIs with cystic lesions <1 cm (P < 0.05). None of these cysts developed worrisome findings and 4/5 PDACs did not arise from visualized cystic precursor lesion.

CONCLUSIONS

Patients with a cyst ≥1 cm were at increased risk for developing PDAC compared with patients with cyst <1 cm. Pancreatic ductal adenocarcinoma usually did not arise from a recognized cystic lesion.

Pancreatic Cyst Size Measurement on Magnetic Resonance Imaging Compared to Pathology

BACKGROUND

While multiple cyst features are evaluated for stratifying pancreatic intraductal papillary mucinous neoplasms (IPMN), cyst size is an important factor that can influence treatment strategies. When magnetic resonance imaging (MRI) is used to evaluate IPMNs, no universally accepted sequence provides optimal size measurements. T2-weighted coronal/axial have been suggested as primary measurement sequences; however, it remains unknown how well these and maximum all-sequence diameter measurements correlate with pathology size. This study aims to compare agreement and bias between IPMN long-axis measurements on seven commonly obtained MRI sequences with pathologic size measurements.

METHODS

This retrospective cohort included surgically resected IPMN cases with preoperative MRI exams. Long-axis diameter tumor measurements and the presence of worrisome features and/orhigh-risk stigmata were noted on all seven MRI sequences. MRI size and pathology agreement and MRI inter-observer agreement involved concordance correlation coefficient (CCC) and intraclass correlation coefficient (ICC), respectively. The presence of worrisome features and high-risk stigmata were compared to the tumor grade using kappa analysis. The Bland-Altman analysis assessed the systematic bias between MRI-size and pathology.

RESULTS

In 52 patients (age 68 ± 13 years, 22 males), MRI sequences produced mean long-axis tumor measurements from 2.45-2.65 cm. The maximum MRI lesion size had a strong agreement with pathology (CCC = 0.82 (95% CI: 0.71-0.89)). The maximum IPMN size was typically observed on the axial T1 arterial post-contrast and MRCP coronal series and overestimated size versus pathology with bias +0.34 cm. The radiologist interobserver agreement reached ICCs 0.74 to 0.91 on the MRI sequences.

CONCLUSION

The maximum MRI IPMN size strongly correlated with but tended to overestimate the length compared to the pathology, potentially related to formalin tissue shrinkage during tissue processing.

Percentage of Pancreatic Cysts on MRI With a Pancreatic Carcinoma: Systematic Review and Meta-Analysis

BACKGROUND

Pancreatic cystic lesions (PCLs) are frequent on MRI and are thought to be associated with pancreatic adenocarcinoma (PDAC) necessitating long-term surveillance based on older studies suffering from selection bias.

PURPOSE

To establish the percentage of patients with PCLs on MRI with a present or future PDAC.

STUDY TYPE

Systematic review, meta-analysis.

POPULATION

Adults with PCLs on MRI and a present or future diagnosis of PDAC were eligible. MEDLINE, EMBASE, Cochrane Central Register of Controlled Trials, and Scopus were searched to April 2022 (PROSPERO:CRD42022320502). Studies limited to PCLs not requiring surveillance, <100 patients, or those with a history/genetic risk of PDAC were excluded.

FIELD STRENGTH/SEQUENCE

≥1.5 T with ≥1 T2-weighted sequence.

ASSESSMENT

Two investigators extracted data, with discrepancies resolved by a third. QUADAS-2 assessed bias. PDAC was diagnosed using a composite reference standard.

STATISTICAL TESTS

A meta-analysis of proportions was performed at the patient-level with 95% confidence intervals (95% CI).

RESULTS

Eight studies with 1289 patients contributed to the percentage of patients with a present diagnosis of PDAC, and 10 studies with 3422 patients to the percentage with a future diagnosis. Of patients with PCLs on MRI, 14.8% (95% CI 2.4-34.9) had a PDAC at initial MRI, which decreased to 6.0% (2.2-11.3) for studies at low risk of bias. For patients without PDAC on initial MRI, 2.0% (1.1-3.2) developed PDAC during surveillance, similar for low risk of bias studies at 1.9% (0.7-3.6), with no clear trend of increased PDAC for longer surveillance durations. For patients without worrisome features or high-risk stigmata, 0.9% (0.1-2.2) developed PDAC during surveillance. Of 10, eight studies had a median surveillance ≥3 years (range 3-157 months). Sources of bias included retrospectively limiting PCLs to those with histopathology and inconsistent surveillance protocols.

DATA CONCLUSION

A low percentage of patients with PCLs on MRI develop PDAC while on surveillance. The first MRI revealing a PCL should be scrutinized for PDAC.

LEVEL OF EVIDENCE

3 TECHNICAL EFFICACY: Stage 2.

Pancreatic ductal adenocarcinomas concomitant with intraductal papillary mucinous neoplasms of the pancreas: A investigation of those clinicopathological features by analyzing 48 patients who underwent surgery for those lesions

BACKGROUND

Differences between pancreatic ductal adenocarcinomas (PDACs) concomitant with intraductal papillary mucinous neoplasm (IPMN) (C-PDACs), those without IPMN (NC-PDACs) and invasive cancers derived from IPMN (IC-Ds) have not been fully clarified.

METHODS

Forty-eight patients with C-PDAC were included to investigate the differences in 1) clinicopathological features and 2) post-operative courses among the three invasive cancer groups.

RESULTS

1) Characteristics of C-PDACs were mostly similar to those of NC-PDACs; whereas, between C-PDACs and IC-Ds, the rate of mucinous carcinoma (2%/25%, p = 0.003) and pathological stage (IA, 15%/36%, p = 0.033; III, 31%/4%, p = 0.015) significantly differed. Most C-PDACs coexisted with small, multifocal IPMNs without mural nodules. 2) Cumulative 5-year recurrence-free survival (RFS) rate related to extra-pancreatic recurrence was significantly worse in C-PDACs than in IC-Ds (35%/69%, p = 0.008) and was not significantly different between C-PDACs and NC-PDACs (35%/18%). This related to intra-pancreatic recurrence tended to be poor in the order of IC-Ds, C-PDACs, and NC-PDACs (69%/82%/93%).

CONCLUSIONS

Because characteristics of IPMNs remarkably differed between C-PDACs and IC-Ds, another algorithm specific to the early detection of C-PDACs is necessary. Appropriate post-operative managements according to the two types of recurrences may contribute to the improvement in the prognoses of C-PDACs/IC-Ds.

Intraductal Papillary Mucinous Neoplasm of the Pancreas: A Challenging Diagnosis

Intraductal papillary mucinous neoplasm of the pancreas (IPMN) was classified as a distinct entity from mucinous cystic neoplasm by the WHO in 1995. It represents a mucin-producing tumor that originates from the ductal epithelium and can evolve from slight dysplasia to invasive carcinoma. In addition, different aspects of tumor progression may be seen in the same lesion. Three types are recognized, the branch duct variant, the main duct variant, which shows a much higher prevalence for malignancy, and the mixed-type variant, which combines branch and main duct characteristics. Advances in cross-sectional imaging have led to an increased rate of IPMN detection. The main imaging characteristic of IPMN is the dilatation of the pancreatic duct without the presence of an obstructing lesion. The diagnosis of a branch duct IPMN is based on the proof of its communication with the main pancreatic duct on MRI-MRCP examination. Early identification by imaging of the so-called worrisome features or predictors for malignancy is an important and challenging task. In this review, we will present recent imaging advances in the diagnosis and characterization of different types of IPMNs, as well as imaging tools available for early recognition of worrisome features for malignancy. A critical appraisal of current IPMN management guidelines from both a radiologist's and surgeon's perspective will be made. Special mention is made of complications that might arise during the course of IPMNs as well as concomitant pancreatic neoplasms including pancreatic adenocarcinoma and pancreatic endocrine neoplasms. Finally, recent research on prognostic and predictive biomarkers including radiomics will be discussed.

Clinical and Molecular Attributes and Evaluation of Pancreatic Cystic Neoplasm

Intraductal papillary mucinous neoplasms (IPMNs) and mucinous cystic neoplasms (MCNs) are all considered "Pancreatic cystic neoplasms (PCNs)" and show a varying risk of developing into pancreatic ductal adenocarcinoma (PDAC). These lesions display different molecular characteristics, mutations, and clinical manifestations. A lack of detailed understanding of PCN subtype characteristics and their molecular mechanisms limits the development of efficient diagnostic tools and therapeutic strategies for these lesions. Proper in vivo mouse models that mimic human PCNs are also needed to study the molecular mechanisms and for therapeutic testing. A comprehensive understanding of the current status of PCN biology, mechanisms, current diagnostic methods, and therapies will help in the early detection and proper management of patients with these lesions and PDAC. This review aims to describe all these aspects of PCNs, specifically IPMNs, by describing the future perspectives.

Long-standing diabetes mellitus increases concomitant pancreatic cancer risk in patients with intraductal papillary mucinous neoplasms

BACKGROUND

When monitoring patients with an intraductal papillary mucinous neoplasm (IPMN), it is important to consider both IPMN-derived carcinoma and concomitant ductal adenocarcinoma (PDAC). The latter is thought to have a poorer prognosis. We retrospectively analyzed the risk factors for concomitant PDAC in IPMN.

METHODS

In total, 547 patients with pancreatic cysts, including IPMNs inappropriate for surgery on initial diagnosis, encountered from April 2005 to June 2019, were reviewed. We performed surveillance by imaging examination once or twice a year.

RESULTS

Five IPMNs with high-grade dysplasia and one IPMN associated with invasive carcinoma were encountered. In comparison, 14 concomitant PDACs were encountered. The prognosis was very poor for concomitant PDACs. All 14 PDAC patients had IPMNs. In patients with IPMNs, long-standing diabetes mellitus was the only significant risk factor for concomitant PDAC in both univariate and multivariate analyses (P < 0.001 and P < 0.01, respectively). Furthermore, patients with IPMNs and diabetes mellitus had a high frequency of concomitant PDACs (9.5%, 9/95) in a median 48-month surveillance period.

CONCLUSIONS

When monitoring IPMNs, the development of not only IPMN-derived carcinomas but also concomitant PDACs should be considered. During this period, it may be prudent to concentrate on patients with other risk factors for PDAC, such as long-standing diabetes mellitus.

Long-term outcomes of patients with multifocal intraductal papillary mucinous neoplasm following pancreatectomy

BACKGROUND

The decision to perform surgery is complicated by the presence of multifocal (MF) intraductal papillary mucinous neoplasms (IPMNs), which are characterized by two or more cysts located in different areas of the pancreas.

OBJECTIVES

We aimed to establish a suitable treatment strategy and surgical indications in patients with MF-IPMNs.

METHODS

This single-center retrospective study included patients with IPMNs who underwent pancreatic resection from 2006 to 2020. Patients with distant metastasis and patients with IPMNs of the main pancreatic duct were excluded from the analysis.

RESULTS

After excluding 22 patients, 194 patients were included. One hundred thirteen patients (58.2%) had unifocal IPMNs, while 81 patients (41.8%) had MF-IPMNs. There were no significant differences in the 5-year disease-specific survival (DSS) rate (92.3% vs. 92.4%, p = 0.976) and the 5-year disease-free survival rate (88.6% vs. 86.5%, p = 0.461). The multivariate analysis identified high-risk stigmata, invasive carcinoma, and lymph node metastasis as independent predictors of DSS. The presence of cystic lesions in the pancreatic remnant was not a predictor of survival. Even in the MF-IPMN group, there were no significant differences in DSS when stratified by procedure (total pancreatectomy vs. segmental pancreatectomy, p = 0.268) or presence of cystic lesions in the pancreatic remnant (p = 0.476). The multivariate analysis identified lymph node metastasis as an independent predictor of DSS in the MF-IPMN group.

CONCLUSIONS

In patients with MF-IPMNs, each cyst should be evaluated individually for the presence of features associated with malignancy.

[Indications for the surgical management of pancreatic neoplasms]

Due to its rising incidence, pancreatic neoplasia, which mainly include adenocarcinomas, neuroendocrine and cystic neoplasia of the pancreas, is becoming increasingly relevant in everyday clinical practice.Based on a systematic literature search, a working group of pancreatic experts developed evidence-based recommendations for surgical indications in pancreatic neoplasia to improve the quality.There is a clear surgical indication for primary or secondary resectable pancreatic carcinomas without metastasis, for functionally active, symptomatic and functionally inactive neuroendocrine neoplasia of more than 2 cm in size and for cystic neoplasm with symptoms or signs of malignancy including all intraductal papillary-mucinous neoplasia (IPMN) of the main duct and mixed type, all mucinous-cystic neoplasia (MCN) > 4 cm and all solid pseudopapillary neoplasia (SPN). Surgery can be indicated for pancreatic carcinomas with isolated arterial vascular infiltration or for long periods of stable oligometastasis, regarding neuroendocrine neoplasias for metastasis or debulking surgery as well as for branch-duct IPMN with risk criteria and MCN <4 cm. There is no primary indication for surgery in locally advanced and metastatic pancreatic cancer or asymptomatic serous-cystic neoplasia (SCN).The indication for surgery should always be individualized taking into account age, comorbidities and patient wishes.

Usefulness of Practitioner-Led Pancreatic Cancer Screening

The 5-year survival rate for pancreatic cancer has improved (10%) but remains worse than that for other cancers. Early pancreatic cancer diagnosis is challenging, and delayed diagnosis can delay treatment, which impairs survival. Practitioners do not promptly refer cases to a general hospital, causing delayed discovery. Herein, we aimed to examine the usefulness of the Pancreatic Cancer Project in Matsue, whose objective is to detect pancreatic cancer in patients presenting at any medical institution in Matsue City. Clinical data were extracted from medical records, and abdominal ultrasonography and tumor marker blood level assessments were performed (n = 234; median age, 71 [range, 41–94] years; 51% male). Cases with abnormal abdominal ultrasonography or blood test findings were referred for specialist imaging and followed up. The pancreatic cancer detection rate was 6.0% (n = 14); all cases were referred to a general hospital by practitioners within 1 month. Patients had stage IA (n = 1), IIA (n = 6), IIB (n = 2), III (n = 1), and IV (n = 4) disease. Overall, pancreatic cancer could be detected at an earlier stage (I–II), but referral to a general hospital by visiting practitioners should be prompt. The Pancreatic Cancer Project in Matsue may help improve the detection and prognosis of pancreatic cancer.

Value of 3-T MR imaging in intraductal papillary mucinous neoplasm with a concomitant invasive carcinoma

OBJECTIVES

To examine the value of 3-T MRI for evaluating the difference between the pancreatic parenchyma of intraductal papillary mucinous neoplasm with a concomitant invasive carcinoma (IPMN-IC) and the pancreatic parenchyma of patients without an IPMN-IC.

METHODS

A total of 132 patients underwent abdominal 3-T MRI. Of the normal pancreatic parenchymal measurements, the pancreas-to-muscle signal intensity ratio in in-phase imaging (SIR-I), SIR in opposed-phase imaging (SIR-O), SIR in T2-weighted imaging (SIR-T2), ADC (×10^-3 mm²/s) in DWI, and proton density fat fraction (PDFF [%]) in multi-echo 3D DIXON were calculated. The patients were divided into three groups (normal pancreas group: n = 60, intraductal papillary mucinous neoplasm (IPMN) group: n = 60, IPMN-IC group: n = 12).

RESULTS

No significant differences were observed among the three groups in age, sex, body mass index, prevalence of diabetes mellitus, and hemoglobin A1c (p = 0.141 to p = 0.657). In comparisons among the three groups, the PDFF showed a significant difference (p < 0.001), and there were no significant differences among the three groups in SIR-I, SIR-O, SIR-T2, and ADC (p = 0.153 to p = 0.684). The PDFF of the pancreas was significantly higher in the IPMN-IC group than in the normal pancreas group or the IPMN group (p < 0.001 and p < 0.001, respectively), with no significant difference between the normal pancreas group and the IPMN group (p = 0.916).

CONCLUSIONS

These observations suggest that the PDFF of the pancreas is associated with the presence of IPMN-IC.

KEY POINTS

• The cause and risk factors of IPMN with a concomitant invasive carcinoma have not yet been clarified. • The PDFF of the pancreas was significantly higher in the IPMN-IC group than in the normal pancreas group or the IPMN group. • Pancreatic PDFF may be a potential biomarker for the development of IPMN with a concomitant invasive carcinoma.

[Pancreatic cystic space-occupying lesions-Diagnostics, treatment and follow-up care : Current recommendations taking the current German S3 guidelines on pancreatic cancer into account]

Due to their increased detection pancreatic cystic space-occupying lesions are becoming increasingly relevant in the clinical routine and represent a morphologically and biologically heterogeneous and thus clinically demanding as well as potentially (pre)malignant entity. As a result, recommendations for the diagnostics and treatment of pancreatic cystic tumors have now been incorporated into the current German S3 guidelines on pancreatic cancer. The diagnostics of pancreatic cystic space-occupying lesions are based on the following three elements: collection of relevant clinical information, performance of high-resolution imaging procedures and if diagnostic uncertainty persists, puncture diagnostics. Differentiated diagnostics are of essential importance as these represent the basis for an adequate treatment decision. Pancreatic cystic lesions with a relevant risk of malignant transformation, e.g., main duct intraductal papillary mucinous neoplasms (IPMN), followed by mucinous cystic neoplasms (MCN), solid pseudopapillary neoplasms (SPN) and generally pancreatic cystic lesions with risk factors independent of the entity, should be resected, whereas a differentiated and individualized approach is necessary, especially for branch-duct IPMNs. The serous cystic neoplasms (SCN) have no malignant potential and do not require any treatment if they are asymptomatic. Important principles in surgery of pancreatic cancer, such as adequate surgical resection taking oncological standards into account and standardized appropriate histopathological processing of the specimens as well as intraoperative frozen section analysis also play an important role in pancreatic cystic space-occupying lesions. An annual follow-up seems to be meaningful, especially for IPMNs.

Peroral Pancreatoscopy with Videoscopy and Narrow-Band Imaging in Intraductal Papillary Mucinous Neoplasms with Dilatation of the Main Pancreatic Duct

Background/Aims

Endoscopic evaluation of intraductal papillary mucinous neoplasms (IPMNs) is useful in determining whether the lesions are benign or malignant. This study aimed to examine the usefulness of peroral pancreatoscopy (POPS) in determining the prognosis of IPMNs.

Methods

POPS with videoscopy was performed using the mother–baby scope technique. After surgery, computed tomography/magnetic resonance cholangiopancreatography or ultrasonography and blood tests were performed every 6 months during the follow-up.

Results

A total of 39 patients with main pancreatic duct (MPD)–type IPMNs underwent POPS using a videoscope, and the protrusions in the MPD were observed in 36 patients. The sensitivity and specificity of cytology/biopsy performed at the time of POPS were 85% and 87.5%, respectively. Of 19 patients who underwent surgery, 18 (95%) patients had negative surgical margins and 1 (5%) patient had a positive margin.

Conclusions

In IPMNs with dilatation of the MPD, POPS is considered effective if the lesions can be directly observed. The diagnosis of benign and malignant lesions is possible depending on the degree of lesion elevation. However, in some cases, slightly elevated lesions may increase in size during the follow-up or multiple lesions may be simultaneously present; therefore, careful follow-up is necessary.

Pancreatic Cystic Lesions and Malignancy: Assessment, Guidelines, and the Field Defect

The widespread use of high-spatial-resolution cross-sectional imaging has led to an increase in detection of incidental pancreatic cystic lesions. These lesions are a diverse group, ranging from indolent and premalignant lesions to invasive cancers. The diagnosis of several of these lesions can be suggested on the basis of their imaging appearance, while many other lesions require follow-up imaging and/or aspiration. The smaller cystic lesions, often branch-duct intraductal papillary mucinous neoplasms, have overlapping imaging characteristics that make diagnostic assessment of the natural history and malignancy risk confusing. Expert panels have developed societal guidelines, based on a consensus, for surveillance of these lesions. However, these guidelines are often inconsistent and are constantly evolving as additional scientific data are accumulated. Identification of features associated with increased risk of malignancy is important for proper management. The concept of field defect, whereby pancreatic adenocarcinoma develops at a site different from the site of the pancreatic cyst, adds to the complexity of screening guidelines. As a result of the differences in guidelines, key stakeholders (eg, radiologists, gastroenterologists, and surgeons) must review and come to a consensus regarding which guideline, or combination of guidelines, to follow at their individual institutions. Standardized reporting and macros are helpful for ensuring the uniformity of interpretations. Radiologists play a critical role in the detection and characterization of pancreatic cystic lesions, in the follow-up recommendations for these lesions, and in the detection of associated cancer. An invited commentary by Zaheer is available online. Online supplemental material is available for this article. ^©RSNA, 2021.

Clinical Utility and Limitation of Diagnostic Ability for Different Degrees of Dysplasia of Intraductal Papillary Mucinous Neoplasms of the Pancreas Using 18F-Fluorodeoxyglucose-Positron Emission Tomography/Computed Tomography

Simple Summary

Elucidating risk factors for different degrees of dysplasia of intraductal papillary mucinous neoplasms (IPMNs) of the pancreas is important in determining strategies for management. In this study, we searched for risk factors for different degrees of dysplasia of IPMNs. Our study indicated that there were no useful factors that significantly differentiated low-grade dysplasia and high-grade dysplasia; however, ¹⁸F-fluorodeoxyglucose–positron emission tomography/computed tomography is useful for differentiating between non-invasive and invasive IPMNs. Our results offer critical information that may determine surgical treatment strategies.

Abstract

The diagnostic value of ¹⁸F-fluorodeoxyglucose (FDG) uptake in the management of intraductal papillary mucinous neoplasms (IPMNs) of the pancreas remains unclear. This study aimed to assess the role of FDG uptake in the diagnosis of different degrees of dysplasia of IPMNs. We retrospectively analyzed the following three points in 84 patients with IPMNs: (1) risk factors to predict high-grade dysplasia (HGD) and invasive carcinoma (INV); (2) the relationship between FDG uptake and glucose transporter 1 (GLUT-1) expression; and (3) the relationship between FDG uptake and the presence of mural nodules. The histopathological diagnosis was low-grade dysplasia (LGD) in 43 patients, HGD in 16, and INV in 25. The maximum standardized uptake value (SUV-max) was significantly higher in INV than in LGD/HGD (p < 0.0001, p = 0.0136). The sensitivity and specificity to discriminate INV from LGD/HGD were 80.0% and 86.2%, respectively, using the receiver operator characteristic curve, when the optimal cutoff score of SUV-max was set at 4.03. Those values were not different between HGD and LGD. More than half of HGD patients had low GLUT-1 expression. Taken together, FDG-PET/CT is useful in distinguishing between non-invasive and invasive IPMN. Our results offer critical information that may determine surgical treatment strategies.

Contemporary indications for upfront total pancreatectomy

Currently, advances in surgical techniques, improvements in perioperative care, new formulations of intermediate and long-acting insulin and of modern pancreatic enzyme preparations have allowed obtaining good short and long-term results and quality of life, especially in high-volume centres in performing total pancreatectomy (TP).Thus, the surgeon's fear in performing TP is not justified and total pancreatectomy can be considered a viable option in selected patients in high-volume centres. The aim of this review was to define the current indications for this procedure, in particular for upfront TP, considering not only the pancreatic disease, but also the surgical approach (open, mini-invasive) and the relationship with vascular resection.

Long-term outcome after EUS-guided radiofrequency ablation: Prospective results in pancreatic neuroendocrine tumors and pancreatic cystic neoplasms

Background and study aims  Endoscopic ultrasound-guided radiofrequency ablation (EUS-RFA) for pancreatic neuroendocrine tumors (NETs) and intraductal pancreatic mucinous neoplasia (IPMN) with worrisome features or high-risk stigmata (WF/HRS) has been evaluated in few series with short-term outcomes. This study's primary endpoint was to assess the long-term efficacy of EUS-RFA in patients with NETs or pancreatic cystic neoplasms (PCNs) over at least 3 years. Patients and methods  Twelve patients had 14 NETs with a mean 13.4-mm size (10-20) and 17 patients had a cystic tumor (16 IPMN, 1 MCA) with a 29.1-mm mean size (9-60 were included. They were treated with EUS-guided RFA, evaluated prospectively at 1 year, and followed annually for at least 3 years. Results  The mean duration of follow-up was 42.9 months (36-53). Four patients died during follow-up (17-42 months) from unrelated diseases. At 1-year follow-up, and 85.7 % complete disappearance was seen in 12 patients with 14 NETs. At the end of follow-up (45.6 months), complete disappearance of tumors was seen in 85.7 % of cases. One case of late liver metastasis occurred in a patient with initial failure of EUS-RFA. At 1-year follow-up, a significant response was seen in 70.5 % of 15 patients with PCNs. At the end of the follow-up, there was a significant response in 66.6 % with no mural nodules. Two cases of distant pancreatic adenocarcinoma unrelated to IPMN occurred. Conclusions  EUS-RFA results for pancreatic NETs or PCNs appear to be stable during 42 months of follow-up.

Prognostic impact of conservative surgery for pancreatic IPMNs

BACKGROUND

The extent of pancreatic resection for intraductal papillary mucinous neoplasms (IPMNs) remains an unresolved issue. The study aims at analyzing the prognostic impact of conservative surgery (CS) i.e. of pancreatoduodenectomy or distal pancreatectomy, versus total pancreatectomy (TP), for pancreatic IPMNs.

METHODS

We retrospectively analyzed and compared data of patients who had undergone pancreatic resection for IPMNs at our center between November 2007 and April 2019. Patients were divided into two main groups based on the extent of surgery: TP-group and CS-group. Subsequently, the perioperative and the long-term outcomes were compared. Moreover, a sub-group analysis of patients with IPMN alone and patients with malignant IPMN, based on preoperative indications to surgery and post-operative histopathological findings, was also performed.

RESULTS

Fifty-three patients were included in the TP-group and 73 in the CS-group. In 50 (39.7%) cases the frozen section changed the pre-operative surgical planning, with an extension of the pancreatic resection, in 43 (34.1%) cases up to a total pancreatectomy. Twenty-six patients (20.6%) with low-grade dysplasia at the frozen section underwent CS, while twenty (15.8%) underwent TP. Comparing these two sub-groups no differences were found in surgical IPMN recurrence, nor progression. The rate of overall postoperative complications was 56.6% in the TP-group and 57.5% in the CS-group (p = 0.940). Fifteen patients (20.5%) developed diabetes in the CS-group. None of the patients treated with CS developed a surgical IPMN recurrence or progression during the follow-up period. Comparing OS and DFS of the two groups, we did not find any statistically significant difference (p = 0.619 and 0.315).

CONCLUSION

A timely CS can be considered an appropriate and valid strategy in the surgical treatment of the majority of pancreatic IPMNs, as it can avoid the serious long-term metabolic consequences of TP in patients with a long-life expectancy. On the contrary, TP remains mandatory in case of PDAC or high-risk features involving the entire gland.

Pancreatic Ductal Adenocarcinoma: Epidemiology and Risk Factors

The number of new cases of pancreatic ductal adenocarcinoma is increasing with a cumulative total of 495,773 cases worldwide, making it the fourteenth most common malignancy. However, it accounts for 466,003 deaths per year and is the seventh leading cause of cancer deaths. Regional differences in the number of patients with pancreatic ductal adenocarcinoma appear to reflect differences in medical care, as well as racial differences. Compared to the prevalence of other organ cancers in Japan, pancreatic ductal adenocarcinoma ranks seventh based on the number of patients, eighth based on morbidity, and fourth based on the number of deaths, with a continuing increase in the mortality rate. Risk factors for developing pancreatic ductal adenocarcinoma include family history, genetic disorders, diabetes, chronic pancreatitis, and intraductal papillary mucinous neoplasms. An issue that hinders improvement in the prognosis of patients with pancreatic ductal adenocarcinoma is the development of a strategy to identify patients with these risk factors to facilitate detection of the disease at a stage when intervention will improve survival.

Pre-Operative Imaging and Pathological Diagnosis of Localized High-Grade Pancreatic Intra-Epithelial Neoplasia without Invasive Carcinoma

Pancreatic ductal adenocarcinoma (PDAC) arises from precursor lesions, such as pancreatic intra-epithelial neoplasia (PanIN) and intraductal papillary mucinous neoplasm (IPMN). The prognosis of high-grade precancerous lesions, including high-grade PanIN and high-grade IPMN, without invasive carcinoma is good, despite the overall poor prognosis of PDAC. High-grade PanIN, as a lesion preceding invasive PDAC, is therefore a primary target for intervention. However, detection of localized high-grade PanIN is difficult when using standard radiological approaches. Therefore, most studies of high-grade PanIN have been conducted using specimens that harbor invasive PDAC. Recently, imaging characteristics of high-grade PanIN have been revealed. Obstruction of the pancreatic duct due to high-grade PanIN may induce a loss of acinar cells replaced by fibrosis and lobular parenchymal atrophy. These changes and additional inflammation around the branch pancreatic ducts (BPDs) result in main pancreatic duct (MPD) stenosis, dilation, retention cysts (BPD dilation), focal pancreatic parenchymal atrophy, and/or hypoechoic changes around the MPD. These indirect imaging findings have become important clues for localized, high-grade PanIN detection. To obtain pre-operative histopathological confirmation of suspected cases, serial pancreatic-juice aspiration cytologic examination is effective. In this review, we outline current knowledge on imaging characteristics of high-grade PanIN.

Detecting Early Pancreatic Cancer: Current Problems and Future Prospects

The number of patients with pancreatic cancer (PC) is currently increasing in both Korea and Japan. The 5-year survival rate of patients with PC 13.0%; however, resection with minimal invasion (tumor size: ≤10 mm) increases the 5-year survival rate to 80%. For this reason, early detection is essential, but most patients with early-stage PC are asymptomatic. Early detection of PC has been reported to require screening of high-risk individuals (HRIs), such as those with a family history of PC, inherited cancer syndromes, intraductal papillary mucinous neoplasm, or chronic pancreatitis. Studies on screening of these HRIs have confirmed a significantly better prognosis among patients with PC who were screened than for patients with PC who were not screened. However, to date in Japan, most patients with early-stage PC diagnosed in routine clinics were not diagnosed during annual health checks or by surveillance; rather, PC was detected in these patients by incidental findings during examinations for other diseases. We need to increase the precision of the PC screening and diagnostic processes by introducing new technologies, and we need to pay greater attention to incidental clinical findings.

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.

Prospective Study Using Plasma Apolipoprotein A2-Isoforms to Screen for High-Risk Status of Pancreatic Cancer. Cancers (Basel). 2020;12. [PMID: 32937962 PMCID: PMC7564617 DOI: 10.3390/cancers12092625]

Simple Summary

Apolipoprotein A2 isoforms (apoA2-i) have been identified as minimally invasive biomarkers for detecting pancreatic cancer (PC) and high-risk individuals for PC. We investigated the efficiency of an enrichment strategy for high-risk individuals using a combination of blood testing for apoA2-i with imaging examinations in the general population. We enrolled 5120 subjects in experimental pancreatic cancer screening, with 84 subjects (1.3%) showing abnormal results for apoA2-i. Pancreatic diseases were recognized in about 30% of subjects with an apoA2-ATQ/AT level of ≤35 μg/mL. Among them, 1 pancreatic cancer and 15 high-risk individuals with intraductal papillary mucinous neoplasm were detected. ApoA2-i has the potential to enrich PC and high-risk status by increasing the diagnostic probability before imaging examinations.

Abstract

Apolipoprotein A2-ATQ/AT (apoA2-ATQ/AT) has been identified as a minimally invasive biomarker for detecting pancreatic cancer (PC) and high-risk (HR) individuals for PC. To establish an efficient enrichment strategy for HR, we carried out a plasma apoA2-ATQ/AT level-based prospective screening study among the general population. The subjects for the screening study were recruited at six medical check-up facilities in Japan between October 2015 and January 2017. We evaluated the positive predictive value (PPV) of the plasma apoA2-ATQ/AT level of ≤35 μg/mL for detecting PC and HR. Furthermore, we prospectively confirmed its diagnostic accuracy with another post-diagnosis population in a cross-sectional study. We enrolled 5120 subjects in experimental screening, with 84 subjects (1.3%) showing positive results for apoA2-ATQ/AT. Pancreatic abnormalities were recognized in 26 of the 84 subjects from imaging examinations. Pancreatic abnormalities detected included 1 PC and 15 HR abnormalities, such as cystic lesions including intraductal papillary mucinous neoplasm. The PPV of apoA2-ATQ/AT for detecting PC and HR was 33.3%. Moreover, a combination study with another cross-sectional study revealed that the area under the curve for apoA2-ATQ/AT to distinguish PC from healthy controls was 0.903. ApoA2-ATQ/AT has the potential to enrich PC and HR by increasing the diagnostic probability before imaging examinations.

Factors affecting the ability of abdominal ultrasonography to detect focal pancreatic lesions identified using endoscopic ultrasonography

Purpose

This study was conducted to determine which factors influence the ability of abdominal ultrasonography (US) to detect focal pancreatic lesions identified using endoscopic ultrasonography (EUS).

Methods

In this study, 338 consecutive patients with focal pancreatic lesions (cyst, n=253; adenocarcinoma, n=54; pancreatic neuroendocrine tumor, n=24; solid pseudopapillary neoplasm, n=4; intrapancreatic accessory spleen, n=1; metastasis, n=1; and lymphoma, n=1) detected by EUS who underwent US were enrolled. We reviewed their radiologic reports and assessed the presence or absence of a focal lesion, the multiplicity of the lesions, and their size and location on US. We evaluated how these parameters differed depending on whether the lesion was solid or cystic. Univariate and multivariate logistic regression analysis were performed.

Results

The overall detection rate of focal pancreatic lesions by US was 61.5% (208 of 338). Using US, the detection rate of cystic lesions was 58.5% (148 of 253), while that of solid lesions was 70.6% (60 of 85). In the univariate analysis, location in the neck or body, solid characteristics, and a relatively large size (15.50±10.08 mm vs. 23.09±12.93 mm) were associated with a significantly higher detection rate (P<0.001, P=0.047, and P<0.001, respectively). In the multivariate analysis, location in the neck or body (odds ratio [OR], 3.238; 95% confidence interval [CI], 1.926 to 5.443; P<0.001) and size (OR, 1.070; 95% CI, 1.044 to 1.096; P<0.001) were proven to be significant predictors of detectability (P<0.001).

Conclusion

US is useful for detecting focal pancreatic lesions, especially when they are located in the neck or body and are relatively large.

[Indications for the Surgical Management of Pancreatic Cystic Lesions]

A steady improvement in modern imaging as well as increasing age in society have led to an increasing number of cystic pancreatic tumours being detected. Pancreatic cysts are a clinically challenging entity because they span a broad biological spectrum and their differentiation is often difficult, especially in small tumours. Therefore, they require a differentiated indication for indication of surgery. To determine recommendations for the surgical indication in cystic tumours of the pancreas, a quality committee for pancreatic diseases of the German Society for General and Visceral Surgery performed a systematic literature search and created this review. Based on the current evidence, signs of malignancy and high-risk criteria (icterus due to cystic pancreatic duct obstruction in the bile duct, enhancing mural nodules ≥ 5 mm or solid components in the cyst or pancreatic duct ≥ 10 mm), as well as symptoms, are a surgical indication, independently of the cyst entity (except pseudocysts). If the entity of the pancreatic cyst is detectable by diagnostic imaging, all main duct IPMN and IPMN of the mixed type, all MCN > 4 cm and all SPN should be resected. SCN and branch-duct IPMN without worrisome features do not constitute an indication for surgery. The indication of operation in branch-duct IPMN with relative risk criteria and MCN < 4 cm is the subject of current discussions and should be individualised. By defining indication recommendations, the present work aims to improve the indication quality in cystic pancreatic tumours. However, the surgical indication should always be individualised, taking into account age, comorbidities and the patient's wishes.

Multimodal radiomics and cyst fluid inflammatory markers model to predict preoperative risk in intraductal papillary mucinous neoplasms

Purpose: Our paper contributes to the burgeoning field of surgical data science. Specifically, multimodal integration of relevant patient data is used to determine who should undergo a complex pancreatic resection. Intraductal papillary mucinous neoplasms (IPMNs) represent cystic precursor lesions of pancreatic cancer with varying risk for malignancy. We combine previously defined individual models of radiomic analysis of diagnostic computed tomography (CT) with protein markers extracted from the cyst fluid to create a unified prediction model to identify high-risk IPMNs. Patients with high-risk IPMN would be sent for resection, whereas patients with low-risk cystic lesions would be spared an invasive procedure. Approach: Retrospective analysis of prospectively acquired cyst fluid and CT scans was undertaken for this study. A predictive model combining clinical features with a cyst fluid inflammatory marker (CFIM) was applied to patient data. Quantitative imaging (QI) features describing radiomic patterns predictive of risk were extracted from scans. The CFIM model and QI model were combined into a single predictive model. An additional model was created with tumor-associated neutrophils (TANs) assessed by a pathologist at the time of resection. Results: Thirty-three patients were analyzed (7 high risk and 26 low risk). The CFIM model yielded an area under the curve (AUC) of 0.74. Adding the QI model improved performance with an AUC of 0.88. Combining the CFIM, QI, and TAN models further increased performance to an AUC of 0.98. Conclusions: Quantitative analysis of routinely acquired CT scans combined with CFIMs provides accurate prediction of risk of pancreatic cancer progression. Although a larger cohort is needed for validation, this model represents a promising tool for preoperative assessment of IPMN.

Risk Factors for Pancreatic Cancer and the Necessity of Long-Term Surveillance in Patients With Pancreatic Cystic Lesions

OBJECTIVES

Pancreatic cystic lesions (PCLs) are a risk factor for pancreatic cancer (PC). Which PCLs should be surveilled and necessity of long-term observation are still controversial.

METHODS

From January 2000 to March 2016, we enrolled 1137 patients with PCLs observed for 1 year. We defined PCLs with cyst size of greater than 30 mm, main pancreatic duct (MPD) of greater than 5 mm or mural nodule as high-risk group, and others as low-risk group (LRG). Kaplan-Meier method and Cox proportional hazard model were applied to assess incidence and risk factors of PC.

RESULTS

In 107 high-risk group and 1030 LRG patients, mean observation period was 4.3 years and 5.0 years, respectively, and 5-year PC incidence was 12.0% and 2.8%, respectively. In LRG, MPD of greater than 3 mm, diabetes mellitus, and presumed branch-duct intraductal papillary mucinous neoplasia (BD-IPMN), defined as PCLs fulfilling any of multilocular formation, multiplicity, or MPD communication, were independent risk factors for PC. In 450 LRG observed for 5 years, 10-year PC incidence was higher in PCLs with our identified risk factors. There was no PC occurrence in PCLs not presumed BD-IPMN after 5-year observation.

CONCLUSIONS

Continuous surveillance is needed after 5-year observation, especially in LRG with our identified risk factors. For discontinuing surveillance, PCLs not presumed BD-IPMN at fifth year could be candidates.

Successful treatment with conversion surgery following chemoradiotherapy for unresectable invasive intraductal papillary mucinous neoplasm

INTRODUCTION

Recent advances in chemotherapy and chemoradiotherapy (CRT) have enabled the use of conversion surgery in selected patients with initially unresectable pancreatic duct adenocarcinoma after a favorable response to preoperative treatment. However, conversion surgery for invasive intraductal papillary mucinous neoplasm (IPMN) has not been reported.

CASE REPORT

A 63-year-old man was referred to our hospital for invasive IPMN treatment. Computed tomography revealed a multilocular tumor of 7.2 × 5.8 cm in diameter, which surrounded approximately 180° of the superior mesenteric artery and totally occluded the superior mesenteric vein (SMV). He was diagnosed with unresectable invasive IPMN. CRT was performed using four cycles of S-1 (100 mg/day) based on body surface area for 14 days every 3 weeks plus gemcitabine 1,000 mg/m² on days 8 and 15 with concurrent radiotherapy (50.4 Gy in 28 fractions). Response to chemotherapy revealed partial response according to the Response Evaluation Criteria in Solid Tumors; subsequently, subtotal stomach-preserving pancreaticoduodenectomy with SMV resection was performed. The postoperative course was uneventful. Four courses of adjuvant chemotherapy with TS-1 100 mg / day were administered postoperatively. At 5 years and 9 months after initiating treatment, the patient was alive without recurrence.

Long-term Risk of Malignancy in Branch-Duct Intraductal Papillary Mucinous Neoplasms

BACKGROUND & AIMS

Long-term outcomes of patients with branch-duct intraductal papillary mucinous neoplasms (IPMNs), particularly those after 5 years of surveillance, have not been fully evaluated in large studies. We analyzed incidences of IPMN-derived carcinoma and concomitant ductal adenocarcinoma (pancreatic ductal adenocarcinoma [PDAC]) over 20 years in a large population of patients.

METHODS

We identified 1404 consecutive patients (52% women; mean age, 67.5 years) with a diagnosis of branch-duct IPMN, from 1994 through 2017, at the University of Tokyo in Japan. Using a competing risk analysis, we estimated cumulative incidence of pancreatic carcinoma, overall and by carcinoma type. We used competing risks proportional hazards models to estimate subdistribution hazard ratios (SHRs) for incidences of carcinomas. To differentiate IPMN-derived and concomitant carcinomas, we collected genomic DNA from available paired samples of IPMNs and carcinomas and detected mutations in GNAS and KRAS by polymerase chain reaction and pyrosequencing.

RESULTS

During 9231 person-years of follow-up, we identified 68 patients with pancreatic carcinomas (38 patients with IPMN-derived carcinomas and 30 patients with concomitant PDACs); the overall incidence rates were 3.3%, 6.6%, and 15.0% at 5, 10, and 15 years, respectively. Among 804 patients followed more than 5 years, overall cumulative incidence rates of pancreatic carcinoma were 3.5% at 10 years and 12.0% at 15 years from the initial diagnosis. The size of the IPMN and the diameter of the main pancreatic duct associated with incidence of IPMN-derived carcinoma (SHR 1.85; 95% confidence interval 1.38-2.48 for a 10-mm increase in the IPMN size and SHR 1.56; 95% confidence interval 1.33-1.83 for a 1-mm increase in the main pancreatic duct diameter) but not with incidence of concomitant PDAC.

CONCLUSIONS

In a large long-term study of patients with branch-duct IPMNs, we found the 5-year incidence rate of pancreatic malignancy to be 3.3%, reaching 15.0% at 15 years after IPMN diagnosis. We observed heterogeneous risk factor profiles between IPMN-derived and concomitant carcinomas.

Value of endoscopy for early diagnosis of pancreatic carcinoma

Despite recent advances in diagnostic imaging modalities, most cases of pancreatic carcinoma are discovered at an unresectable stage, resulting in poor prognosis. Early diagnosis is essential to ensure curative treatment and improve the prognosis of pancreatic carcinoma. Imaging modalities with high diagnostic ability are necessary for the early diagnosis of pancreatic carcinoma. Endoscopic ultrasonography is a reliable and efficient diagnostic modality because it provides superior spatial resolution and should be incorporated into screening programs in patients at high risk of pancreatic carcinoma. Endoscopy facilitates cytopathological diagnosis based on samples collected via endoscopic ultrasonography-guided fine-needle aspiration and endoscopic retrograde cholangiopancreatography. Cytodiagnosis with endoscopic naso-pancreatic drainage is useful in patients with carcinoma in situ. In this review, we highlight the potential role of endoscopy in the early diagnosis of pancreatic carcinoma. We provide an overview of the endoscopy tools used for the diagnosis of pancreatic carcinoma, discuss the diagnostic ability of these tools for small carcinomas and carcinomas in situ, and propose a strategy for endoscopy-based screening of early pancreatic carcinoma.

Pancreatic Cancer Surveillance: Who, When, and How

PURPOSE OF REVIEW

Individuals who have an increased risk for pancreatic cancer (PC) due to personal or family history may benefit from surveillance of the pancreas to increase the likelihood of early detection. This review explores current indications for PC surveillance, as well as options for surveillance modality and timing, and data regarding surveillance outcomes.

RECENT FINDINGS

Recently published data suggests that individuals undergoing surveillance who develop PC are more likely to be diagnosed with resectable disease, which improves survival. Several professional organizations have published guidelines for surveillance to help define who should have surveillance, when surveillance should be performed, and how it can be accomplished. PC surveillance should be considered for individuals with a pathogenic variant in a PC-related gene who have an affected first- or second-degree relative and for individuals in a familial pancreatic cancer family who have an affected first-degree relative. Surveillance should begin at age 50, or 10 years before the earliest age of PC diagnosis in the family. Endoscopic ultrasound (EUS) or MRI/MRCP are both reasonable surveillance options, but EUS may be better at detecting small solid changes in the pancreas. Ideally, surveillance should be performed at expert centers in conjunction with research protocols.

Diffusion-weighted image improves detectability of magnetic resonance cholangiopancreatography for pancreatic ductal adenocarcinoma concomitant with intraductal papillary mucinous neoplasm

The present study is aimed to clarify the utility of magnetic resonance cholangiopancreatography (MRCP) and the additional value of diffusion-weighted imaging (DWI) in diagnosing pancreatic ductal adenocarcinoma (PDAC) concomitant with intraductal papillary mucinous neoplasm (IPMN).This retrospective study involved 38 patients with PDAC concomitant with IPMN and 114 patients (control) who were randomly selected from 320 patients with IPMN without PDAC and were matched with cases for magnetic resonance imaging (MRI) strength (1.5 T/3.0 T). Two radiologists reviewed the 2 MR image sets with relevant clinical information blinded, first MRCP alone and then combined MRI set including DWI. Diagnostic capability and interobserver agreement were assessed by using receiver operating characteristics curve (Az) analysis and weighted κ statistics.Az values for the 2 observers were 0.834 and 0.821 for MRCP alone and 0.964 and 0.926 for the combined MRI (P < .001 and P < .001), respectively. The sensitivity of MRCP alone was 61% (23/38), with both observers failing to diagnose PDACs located at the end of tail or away from the pancreatic duct. Meanwhile, with combined MRI, sensitivity was significantly increased for both observers (61% to 92%, P = .002; 61% to 87%, P = .004). Moreover, the interobserver agreement was higher with combined MRI (κ = 0.85) than MRCP alone (κ = 0.59).MRCP and DWI might be a superior option with a higher diagnostic capability of PDAC concomitant with IPMN than MRCP alone, especially for tumors away from the pancreatic duct.

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.

Role of transabdominal ultrasonography in the diagnosis of pancreatic cystic lesions

Pancreatic cystic lesions (PCLs) are incidental findings that are being increasingly identified because of recent advancements in abdominal imaging technologies. PCLs include different entities, with each of them having a peculiar biological behavior, and they range from benign to premalignant or malignant neoplasms. Therefore, accurate diagnosis is important to determine the best treatment strategy. As transabdominal ultrasonography (US) is noninvasive, inexpensive, and widely available, it is considered to be the most appropriate imaging modality for the initial evaluation of abdominal diseases, including PCLs, and for follow-up assessment. We present a review of the possibilities and limits of US in the diagnosis of PCLs, the technical development of US, and the ultrasonographic characteristics of PCLs.

Association Between Pancreatic Cystic Lesions and High-grade Intraepithelial Neoplasia and Aging: An Autopsy Study

OBJECTIVES

This study aimed to clarify clinicopathological features of pancreatic cysts.

METHODS

Pancreata from 280 autopsies (median, 83 years; male, 146; female, 134) were sectioned every 5 mm. Cysts (<10 mm) were diagnosed as a simple cyst or low-grade, intermediate-grade, or high-grade dysplasia.

RESULTS

We found 236 cysts in 93 patients (33.2%). The number and diameter of cysts increased according to the age. Of the 236 cysts, 9 (3.8%) were with high-grade dysplasia. Cysts with high-grade dysplasia arose in the pancreata of older patients with larger numbers of cysts. In contrast, 15 noncystic lesions with high-grade dysplasia were also detected. Hence, in total, 24 high-grade dysplastic lesions in 15 patients (5.4%) were noted. Of the 15 patients with high-grade dysplastic lesions, in 10 patients, the condition was accompanied by pancreatic cysts, whereas 5 patients did not have any cysts in the pancreas; therefore, patients with cyst showed higher incidence of high-grade dysplasia (10.8%; P = 0.0047) than patients without cyst (2.7%). All cysts with high-grade dysplasia were located in the branch duct of the pancreatic head/body, whereas 20% of noncystic lesions with high-grade dysplasia were located in the main pancreatic duct.

CONCLUSIONS

Cystic lesions with high-grade dysplasia may have different characteristics compared with noncystic high-grade dysplasia.

Mutational Patterns in Pancreatic Juice of Intraductal Papillary Mucinous Neoplasms and Concomitant Pancreatic Cancer

OBJECTIVES

The aims of this study were to identify genetic characteristics of intraductal papillary mucinous neoplasm (IPMN)-associated pancreatic ductal carcinoma (PDC) and to detect these markers using pancreatic juice.

METHODS

From 76 cases, 102 tissues were obtained: 29 cases were noninvasive IPMN, 18 were PDC derived from IPMN (D-PDC; noninvasive part, n = 16; invasive part, n = 18), and 29 were PDC concomitant with IPMN (C-PDC; IPMN part, n = 10; PDC part, n = 29). Moreover, pancreatic juice samples from 28 cases were obtained (noninvasive IPMN, n = 13; D-PDC, n = 7; C-PDC, n = 8). Fifty-one cancer-related genes were analyzed by next-generation sequencing.

RESULTS

TP53 mutation rates in D-PDC, C-PDC, and noninvasive IPMN were 67%, 66%, and 10%, respectively. Moreover, KRAS mutational patterns between 2 simultaneous tumors differed in 1 (6.3%) of the 16 D-PDC cases and in 8 (80%) of the 10 C-PDC cases (P = 0.0006). TP53 or multiple KRAS mutations were detected using pancreatic juice more frequently in C-PDC cases than in noninvasive IPMN cases (75% and 23%, respectively, P = 0.03).

CONCLUSIONS

Multiple KRAS mutations along with TP53 mutation are genetic markers for C-PDC, which could be detected using pancreatic juice preoperatively.

High-risk lesions in the remnant pancreas: fate of the remnant pancreas after pancreatic resection for pancreatic cancer and intraductal papillary mucinous neoplasms

Progress in diagnostic modalities, surgical procedures, and multidisciplinary treatment for pancreatic diseases has increased the number of long-term survivors after pancreatic resection. Several reports have focused on high-risk lesions (HRLs), including high-grade pancreatic intraepithelial neoplasia (PanIN), pancreatic ductal adenocarcinoma, high-grade intraductal papillary mucinous neoplasm (IPMN), and IPMN with an associated invasive carcinoma, in the remnant pancreas after partial pancreatic resection for pancreatic cancer or IPMN. The etiology of HRLs in the remnant pancreas is thought to be either isolated local recurrence of the initial lesion in the remnant pancreas or a newly developed primary lesion. Although it is difficult to distinguish between local recurrence and a new primary lesion, comparison of genetic alterations between two lesions may help with this distinction. Early detection of HRLs in the remnant pancreas may improve the prognosis of patients, and several investigators have proposed predictive factors for HRLs in the remnant pancreas after partial pancreatic resection for pancreatic cancer or IPMN. The reported short- and long-term outcomes of surgical resection of HRLs in the remnant pancreas are relatively favorable. Life-long surveillance of the remnant pancreas is recommended after partial pancreatic resection for pancreatic cancer or IPMN.

Increased Risk of Second Primary Cancers Following Diagnosis of Malignant Intraductal Papillary Mucinous Neoplasms of the Pancreas: A Population-Based Study

Introduction: Several studies have reported that intraductal papillary mucinous neoplasms (IPMNs) of the pancreas are associated with extra-pancreatic malignancies. However, there have been no population-based studies evaluating the risk of second primary cancers (SPCs) in patients with pancreatic IPMN.

Methods: The Surveillance, Epidemiology, and End Results (SEER) database was used to identify and characterize data from patients with IPMN of the pancreas. The standard incidence ratio (SIR) of this cancer was calculated by estimating the relative risk (RR). A multivariate Cox regression model was used to estimate hazards ratios (HRs) of death and associated 95% CIs.

Results: Of 2,850 patients with IPMN of the pancreas, 104 patients (3.65%) developed 118 SPCs. The SIR for all SPCs combined was 1.22 (95% confidence interval [CI] = 1.01–1.46; P < 0.05). There was an elevated risk of site-specific SPCs in the small intestine (SIR = 8.68; 95% CI = 2.36–22.22), pancreas (SIR = 2.66; 95% CI = 1.15–5.25), urinary bladder (SIR = 2.02; 95% CI = 1.05–3.54), and eye and orbit (SIR = 13.47; 95% CI = 1.63–48.67) in patients with pancreas IPMN. In age subgrouping, people aged younger than 50 years had an increased risk of all-site SPC with an SIR of 6.44 (95% CI = 2.78–12.68). Cox regression modeling showed that advanced disease stage and a short latency period carried a higher risk of death in IPMN patients with SPC.

Conclusions: Patients diagnosed with pancreatic IPMNs were at higher risk than the general population for developing a second primary malignancy. Meanwhile, advanced historic stage and short latency period were associated with an elevated HR in IPMN patients who develop an SPC.

Diagnosis and management of pancreatic cystic neoplasms

This review outlines the current classification of pancreatic cystic lesions, with a particular emphasis on pancreatic cystic neoplasms (PCNs). It will describe the diagnostic approach to PCNs, with reference to clinicopathological features, cross-sectional radiology and endoscopic ultrasound. This review will conclude with an evidence-based discussion of the management of PCNs focused on recent clinical guidelines.

Pancreatic cancer screening in patients with presumed branch-duct intraductal papillary mucinous neoplasms

Because delayed diagnosis is one of the causes of poor prognosis in pancreatic ductal adenocarcinoma (PDAC), early detection is a key for overall improvement of prognosis. Towards this end, periodic screening is recommended for individuals considered high-risk for PDAC. Advances in diagnostic imaging modalities have increased the frequency of incidental findings of pancreatic cysts, including the intraductal papillary mucinous neoplasm (IPMN) - a major risk factor of PDAC, having 1% annual prevalence of concomitance with IPMN. Proper retainment of patients with IPMN and regular follow-up by routine imaging examination will likely improve early detection and better prognosis of PDAC. Unfortunately, current guidelines only address management of PDAC derived from IPMN and overlook PDAC concomitant with IPMN. Screening of patients with IPMN, by endoscopic ultrasonography (currently the most reliable modality for detecting small PDAC), may facilitate early detection of both IPMN-derived and -concomitant PDAC. Prospective studies to evaluate the usefulness of endoscopic ultrasonography in screening of IPMN-concomitant PDAC will also help in determining the optimal surveillance strategy for more widespread applications.

Predictors of Malignancy in "Pure" Branch-Duct Intraductal Papillary Mucinous Neoplasm of the Pancreas without Enhancing Mural Nodules on CT Imaging: A Nationwide Multicenter Study

Background/Aims

Presence of enhanced mural nodules, which can be visualized using computed tomography (CT), is one of high-risk stigmata in branch-duct intraductal papillary mucinous neoplasms (BD-IPMNs). Conversely, the absence of enhanced mural nodules on preoperative imaging does not exclude malignant risk. The present study aimed to investigate other morphological features as predictors of malignancy in "pure" BD-IPMNs without enhanced mural nodules on CT.

Methods

This retrospective study included 180 patients with surgically confirmed "pure" BD-IPMNs of the pancreas and no enhanced mural nodules on preoperative CT. The study was conducted at 15 tertiary referral centers throughout South Korea. Univariate and multivariate analyses were used to identify significant predictors of malignancy.

Results

BD-IPMNs with low-grade (n=84) or moderate-grade (n=76) dysplasia were classified as benign; those with high-grade dysplasia (n=8) or invasive carcinoma (n=12) were classified as malignant. The multivariate analysis revealed that cyst size ≥30 mm (odds ratio, 8.6; p=0.001) and main pancreatic duct diameter ≥5 mm (odds ratio, 4.1; p=0.01) were independent risk factors for malignancy in "pure" BD-IPMNs without enhanced mural nodules on CT. Endoscopic ultrasound detected enhanced mural nodules (6/82) that had been missed on CT, and two IPMNs with enhanced mural nodules were malignant.

Conclusions

In patients with "pure" BD-IPMNs who have no enhanced mural nodules on CT, cyst size ≥30 mm and main pancreatic duct diameter ≥5 mm may be associated with malignancy.

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.

[Intraductal papillary mucinous neoplasm of pancreas]

Intraductal papillary mucinous neoplasm (IPMN) is the most common cystic pancreatic tumor. There are 3 ductal types of this tumor depending on localization. Several histological subtypes determine clinical course and prognosis. The problems of diagnosis, surgical treatment and follow-up are reviewed in several guidelines. Literature review devoted to pancreatic IPMN is presented in the article, the latest guidelines are compared.

Current indications and yield of endoscopic ultrasound and ancillary techniques in pancreatic cystic neoplasms

An increase in the diagnosis of pancreatic cystic neoplasm has been described lately. Surgical treatment or surveillance is advised depending on the type of lesion diagnosed. The most accurate diagnostic approach is needed to make the best therapeutic decision. Endoscopic ultrasound is a very valuable tool in the evaluation of pancreatic cystic neoplasm. It generates high-quality images and allows the possibility of sampling the cystic fluid for cytology, microbiological and molecular evaluation. Even with this evaluation, the sensitivity of this approach is not always adequate. New technological resources have been developed to try to improve the diagnostic accuracy of pancreatic cystic neoplasms. The two most promising techniques are needle-based confocal laser endomicroscopy and contrast-enhanced harmonic endoscopic ultrasound. Needle-based confocal laser endomicroscopy allows a microscopic evaluation of mucosal glands and vascular pattern, to differentiate mucinous from non-mucinous lesions. Contrast-enhanced harmonic endoscopic ultrasound is used for the vascular evaluation of the microcirculation of the cyst wall and mural nodule, mainly to make the difference between malignant nodules and mucus plugs. A combination of these different diagnostic techniques can improve the diagnostic accuracy of pancreatic cystic neoplasms to offer the adequate therapeutic decision.

Intraductal papillary mucinous neoplasms of the pancreas: a clinical challenge

The incidental detection rate of intraductal papillary mucinous neoplasms (IPMNs) has significantly increased. However, little is known about the natural history of these tumors. Their optimal management and appropriate follow-up are still unclear. We have, therefore, reviewed the available literature on IPMN focusing on their diagnosis, treatment according to the risk of malignant transformation, and follow-up. Areas covered: Bibliographical searches were performed in PubMed for the terms 'intraductal papillary mucinous neoplasm' and 'natural history' and 'diagnosis' and 'treatment' and 'surgery' and 'follow-up' and 'prognosis.' PubMed was used to search for all the relevant articles published over the last 10 years. A total of 7244 records were identified. After filtering for year range, English language, human studies, article types, and removing duplicates, 74 articles were left with the strongest level of evidence. Expert commentary: Available guidelines for IPMN management are mainly based on expert opinions and may lack strong evidence. Further studies are warranted to better predict the risk of recurrence/future malignancy and to establish standardized guidelines. IPMNs management should be based on multidisciplinary discussion and treatment should be tailored to an individual patient according to patient and tumor characteristics.