Surgically treating a rare and asymptomatic intraductal papillary neoplasm of the bile duct:A case report

BACKGROUND Intraductal papillary neoplasms of the bile duct(IPNBs)are rare and characterized by papillary growth within the bile duct lumen.IPNB is similar to obstructive biliary pathology.In this report,we present an unexpected case of asymptomatic IPNB and consolidate our findings with the relevant literature to augment our understanding of this condition.Integrating relevant literature contributes to a more comprehensive understanding of the disease.CASE SUMMARY A 66-year-old Chinese male patient was admitted to our hospital for surgical intervention after gallstones were discovered during a routine physical examination.Preoperative imaging revealed a lesion on the left side of the liver,which raised the suspicion of IPNB.A laparoscopic left hemihepatectomy was performed,and subsequent histopathological examination confirmed the diagnosis of IPNB.At the 3-mo postoperative follow-up,the patient reported good recovery and no metastasis.IPNB can manifest both latently and asymptomatically.Radical surgical resection is the most effective treatment for IPNB.CONCLUSION Hepatic and biliary masses,should be considered to diagnose IPNB.Prompt surgery and vigilant follow-up are crucial in determining prognosis.

Percutaneous transhepatic cholangioscopy-assisted biliary polypectomy for local palliative treatment of intraductal papillary neoplasm of the bile duct

BACKGROUND Intraductal papillary neoplasm of the bile duct(IPNB)is a premalignant biliarytype epithelial neoplasm with intraductal papillary or villous growth.Currently reported local palliative therapeutic modalities,including endoscopic nasobiliary drainage,stenting and biliary curettage,endoscopic biliary polypectomy,percutaneous biliary drainage,laser ablation,argon plasma coagulation,photodynamic therapy,and radiofrequency ablation to relieve mechanical obstruction are limited with weaknesses and disadvantages.We have applied percutaneous transhepatic cholangioscopy(PTCS)-assisted biliary polypectomy(PTCS-BP)technique for the management of IPNB including mucin-hypersecreting cast-like and polypoid type tumors since 2010.AIM To assess the technical feasibility,efficacy,and safety of PTCS-BP for local palliative treatment of IPNB.METHODS Patients with mucin-hypersecreting cast-like or polypoid type IPNB and receiving PTCS-BP between September 2010 and December 2019 were included.PTCS-BP was performed by using a half-moon type snare with a soft stainless-steel wire,and the tumor was snared and resected with electrocautery.The primary outcome was its feasibility,indicated by technical success.The secondary outcomes were efficacy,including therapeutic success,curative resection,and clinical success,and safety.RESULTS Five patients(four with mucin-hypersecreting cast-like type and one with polypoid type IPNB)were included.Low-and high-grade intraepithelial neoplasia(HGIN)and recurrent IPNB with invasive carcinoma were observed in one,two,and two patients,respectively.Repeated cholangitis and/or obstructive jaundice were presented in all four patients with mucin-hypersecreting cast-like type IPNB.All five patients achieved technical success of PTCS-BP.Four patients(three with mucin-hypersecreting cast-like type and one with polypoid type IPNB)obtained therapeutic success;one with mucin-hypersecreting cast-like type tumors in the intrahepatic small bile duct and HGIN had residual tumors.All four patients with mucin-hypersecreting IPNB achieved clinical success.The patient with polypoid type IPNB achieved curative resection.There were no PTCS-BP-related serious adverse events.CONCLUSION PTCS-BP appears to be feasible,efficacious,and safe for local palliative treatment of both mucin-hypersecreting cast-like and polypoid type IPNB.

Reoperation for heterochronic intraductal papillary mucinous neoplasm of the pancreas after bile duct neoplasm resection:A case report

BACKGROUND Intraductal papillary neoplasm of the bile duct(IPNB)and intraductal papillary mucinous neoplasm(IPMN)of the pancreas have similar pathological manifestations.However,they often develop separately and it is rare for both to occur together.Patients presenting with heterochronic IPMN after IPNB are prone to be misdiagnosed with tumor recurrence.CASE SUMMARY A 67-year-old male patient was admitted 8.5 years after IPNB carcinoma and 4 years after the discovery of a pancreatic tumor.A left hepatic bile duct tumor with distal bile duct dilatation was found 8.5 years ago by the computed tomography;therefore,a left hepatectomy was performed.The postoperative pathological diagnosis was malignant IPNB with negative cutting edge and pathological stage T1N0M0.Magnetic resonance imaging 4 years ago showed cystic lesions in the pancreatic head with pancreatic duct dilatation,and carcinoembryonic antigen continued to increase.Positron emission tomography showed a maximum standard uptake value of 11.8 in the soft tissue mass in the pancreatic head,and a malignant tumor was considered.Radical pancreatoduodenectomy was performed.Postoperative pathological diagnosis was pancreatic head IPMN with negative cutting edge,pancreaticobiliary type,stage T3N0M0.He was discharged 15 d after the operation.Follow-up for 6 mo showed no tumor recurrence,and quality of life was good.CONCLUSION IPNB and IPMN are precancerous lesions with similar pathological characteristics and require active surgery and long-term follow-up.

Intraductal papillary mucinous neoplasm originating from a jejunal heterotopic pancreas:A case report

BACKGROUND Intraductal papillary mucinous neoplasm(IPMN)is a rare pancreatic tumor and has the potential to become malignant.Surgery is the most effective treatment at present,but there is no consensus on the site of resection.Heterotopic pancreas occurs in the gastrointestinal tract,especially the stomach and duodenum but is asymptomatic and rare.We report a case of ectopic pancreas with IPMN located in the jejunum.CASE SUMMARY A 56-year-old male patient suffered from severe pain,nausea and vomiting due to a traffic accident and sought emergency treatment at our hospital.Contrast-enhanced computed tomography of the whole abdomen suggested splenic congestion,which was considered to be splenic rupture.Emergency laparotomy was performed,and the ruptured spleen was removed during the operation.Unexpectedly,a cauliflower-like mass of about 2.5 cm×2.5 cm in size was incidentally found about 80 cm from the ligament of Treitz during the operation.A partial small bowel resection was performed,and postoperative pathology confirmed the small bowel mass as heterotopic pancreas with low-grade IPMN.CONCLUSION Ectopic pancreas occurs in the jejunum and is pathologically confirmed as IPMN after surgical resection.

Synchronous manifestation of colorectal cancer and intraductal papillary mucinous neoplasms

High rates of extrapancreatic malignancies,in particular colorectal cancer(CRC),have been detected in patients with intraductal papillary mucinous neoplasm(IPMN).So far,there is no distinct explanation in the literature for the development of secondary or synchronous malignancies in patients with IPMN.In the past few years,some data related to common genetic alterations in IPMN and other affiliated cancers have been published.This review elucidated the association between IPMN and CRC,shedding light on the most relevant genetic alterations that may explain the possible relationship between these entities.In keeping with our findings,we suggested that once the diagnosis of IPMN is made,special consideration of CRC should be undertaken.Presently,there are no specific guidelines regarding colorectal screening programs for patients with IPMN.We recommend that patients with IPMNs are at high-risk for CRC,and a more rigorous colorectal surveillance program should be implemented.

Differences between main-duct and branch-duct intraductal papillary mucinous neoplasms of the pancreas

In the last decade,intraductal papillary mucinous neoplasms(IPMNs) have become commonly diagnosed.From a morphological standpoint,they are classified in main-duct IPMNs(MD-IPMNs) and branch-duct IPMNs(BD-IPMNs),depending on the type of involvement of the pancreatic ductal system by the neoplasm.Despite the fact that our understanding of their natural history is still incomplete,recent data indicate that MD-IPMNs and BD-IPMNs show significant differences in terms of biological behaviour with MD-IPMNs at higher risk of malignant degeneration.In the present paper,clinical and epidemiological characteristics,rates of malignancy and the natural history of MD-IPMNs and BD-IPMNs are analyzed.The profile of IPMNs involving both the main pancreatic duct and its side branches(combined-IPMNs) are also discussed.Finally,general recommendations for management based on these differences are given.

Outcomes of nonresected main-duct intraductal papillary mucinous neoplasms of the pancreas

AIM:To compare characteristics and outcomes of resected and nonresected main-duct and mixed intraductal papillary mucinous neoplasms of the pancreas(IPMN).METHODS:Over a 14-year period,50 patients who did not undergo surgery for resectable main-duct or mixed IPMN,for reasons of precluding comorbidities,age and/or refusal,were compared with 74 patients who underwent resection to assess differences in rates of survival,recurrence/occurrence of malignancy,and prognostic factors.All study participants had dilatation of the main pancreatic duct by ≥ 5 mm,with or without dilatation of the branch ducts.Some of the nonsurgical patients showed evidence of mucus upon perendoscopic retrograde cholangiopancreatography or endoscopic ultrasound and/or after fine needle aspiration.For the surgical patients,pathologic analysis of resected specimens confirmed a diagnosis of IPMN with involvement of the main pancreatic duct or of both branch ducts as well as the main pancreatic duct.Clinical and biologic follow-ups were conducted for all patients at least annually,through hospitalization or consultation every six months during the first year of follow-up,together with abdominal imaging analysis(magnetic resonance cholangiopancreatography or computed tomography) and,if necessary,endoscopic ultrasound with or without fine needle aspiration.RESULTS:The overall five-year survival rate of patients who underwent resection was significantly greater than that for the nonsurgical patients(74% vs 58%; P =0.019).The parameters of age(< 70 years) and absence of a nodule were associated with better survival(P < 0.05); however,the parameters of main pancreatic duct diameter > 10 mm,branch ductdiameter > 30 mm,or presence of extra pancreatic cancers did not significantly influence the prognosis.In the nonsurgical patients,pancreatic malignancy occurred in 36% of cases within a mean time of 33 mo(median:29 mo; range:8-141 mo).Comparison of the nonsurgical patients who experienced disease progression with those who did not progress showed no significant differences in age,sex,symptoms,subtype of IPMN,or follow-up period; only the size of the main pancreatic duct was significantly different between these two sub-groups,with the nonsurgical patients who experienced progression showing a greater diameter at the time of diagnosis(> 10 mm).CONCLUSION:Patients unfit for surgery have a 36% greater risk of developing pancreatic malignancy of the main-duct or mixed IPMN within a median of 2.5 years.

Epidemiology and outcome of individuals with intraductal papillary neoplasms of the bile duct

BACKGROUND Intraductal papillary neoplasm of the bile duct(IPNB)is a rare distinct subtype of precursor lesions of biliary carcinoma.IPNB is considered to originate from luminal biliary epithelial cells,typically displays mucin-hypersecretion or a papillary growth pattern,and results in cystic dilatation[1].IPNB develops anywhere in the intrahepatic and extrahepatic biliary tracts,and can occur in various pathological stages from low-grade dysplasia to invasive carcinoma.IPNBs have similar phenotypic changes in the occurrence and development of all subtypes,and the prognosis is significantly better than that of traditional(nonpapillary)cholangiocarcinoma.AIM To evaluate the clinicopathological features of IPNB to provide evidence-based guidance for treatment.METHODS Invasive IPNB,invasive intraductal papillary mucinous neoplasm of the pancreas(IPMN),and traditional cholangiocarcinoma data for affected individuals from 1975 to 2016 were obtained from the Surveillance,Epidemiology,and End Results(SEER)database.Annual percentage changes(APCs)in the incidence and incidence-based(IB)mortality were calculated.We identified the independent predictors of overall survival(OS)and cancer-specific survival(CSS)in indivi duals with invasive IPNB.RESULTS The incidence and IB mortality of invasive IPNB showed sustained decreases,with an APC of-4.5%(95%CI:-5.1%to-3.8%)and-3.3%(95%CI:-4.1%to-2.6%)(P<0.001),respectively.Similar decreases in incidence and IB mortality were seen for invasive IPMN but not for traditional cholangiocarcinoma.Both OS and CSS for invasive IPNB were better than for invasive IPMN and traditional cholangiocarcinoma.A total of 1635 individuals with invasive IPNB were included in our prognosis analysis.The most common tumor sites were the pancreaticobiliary ampulla(47.9%)and perihilar tract(36.7%),but the mucin-related subtype of invasive IPNB was the main type,intrahepatically(approximately 90%).In the univariate and multivariate Cox regression analysis,age,tumor site,grade and stage,subtype,surgery,and chemotherapy were associated with OS and CSS(P<0.05).CONCLUSION Incidence and IB mortality of invasive IPNB trended steadily downward.The heterogeneity of IPNB comprises site and the tumor’s mucin-producing status.

International guidelines for the management of pancreatic intraductal papillary mucinous neoplasms

The management of intraductal papillary mucinous neoplasms(IPMN) is presently evolving as a result of the improved understanding of the natural history and biological behavior of the different pancreatic cystic neoplasms; and better preoperative diagnosis of these neoplasms due to advancement in preoperative diagnostic tools. International consensus guidelines for the management of IPMN were first formulated in 2006 and subsequently revised in 2012. Both these guidelines were constructed based on expert opinion and not on robust clinical data. The main limitation of the original Sendai guidelines was that it had a low positive predictive value resulting in many benign neoplasms being resected. Hence,these guidelines were revised in 2012. However,although the updated guidelines resulted in an improvement in the positive predictive value over the Sendai Guidelines,the results of several studies validating these guidelines demonstrated that its positive predictive value remained low. Furthermore,although both guidelines were associated with high negative predictive values,several investigators have demonstrated that some malignant IPMNs may be missed. Finally,it is imperative to emphasize that major considerations when managing a patient with IPMN including the patient's surgical risk,life-expectancy and even cost of investigations are not taken into account in current guidelines. The management of a patient with IPMN should be individualized and tailored according to a patient's risk benefit profile for resection vs surveillance.

Pathological features and diagnosis of intraductal papillary mucinous neoplasm of the pancreas

Intraductal papillary mucinous neoplasm(IPMN) of the pancreas is a noninvasive epithelial neoplasm of mucinproducing cells arising in the main duct(MD) and/or branch ducts(BD) of the pancreas.Involved ducts are dilated and filled with neoplastic papillae and mucus in variable intensity.IPMN lacks ovarian-type stroma,unlike mucinous cystic neoplasm,and is defined as a grossly visible entity(≥ 5 mm),unlike pancreatic intraepithelial neoplasm.With the use of high-resolution imaging techniques,very small IPMNs are increasingly being identified.Most IPMNs are solitary and located in the pancreatic head,although 20%-40% are multifocal.Macroscopic classification in MD type,BD type and mixed or combined type reflects biological differences with important prognostic and preoperative clinical management implications.Based on cytoarchitectural atypia,IPMN is classified into low-grade,intermediategrade and high-grade dysplasia.Based on histological features and mucin(MUC) immunophenotype,IPMNs are classified into gastric,intestinal,pancreatobiliary and oncocytic types.These different phenotypes can be observed together,with the IPMN classified according to the predominant type.Two pathways have been suggested:gastric phenotype corresponds to less aggressive uncommitted cells(MUC1-,MUC2-,MUC5 AC +,MUC6 +) with the capacity to evolve to intestinal phenotype(intestinal pathway)(MUC1-,MUC2 +,MUC5 AC +,MUC6- or weak +) or pancreatobiliary /oncocytic phenotypes(pyloropancreatic pathway)(MUC1 +,MUC 2-,MUC5 AC +,MUC 6 +) becoming more aggressive.Prognosis of IPMN is excellent but critically worsens when invasive carcinoma arises(about 40% of IPMNs),except in some cases of minimal invasion.The clinical challenge is to establish which IPMNs should be removed because of their higher risk of developing invasive cancer.Once resected,they must be extensively sampled or,much better,submitted in its entirety for microscopic study to completely rule out associated invasive carcinoma.

Expression of the tumor suppressor gene maspin and its significance in intraductal papillary mucinous neoplasms of the pancreas

BACKGROUND: Maspin is a member of the serpin family of protease inhibitors and is thought to inhibit carcinoma invasion, metastasis, and angiogenesis and induce apoptosis. We examined maspin expression immunohistochemically and assessed its significance in intraductal papillary mucinous neoplasm (IPMN) of the pancreas. METHODS: We examined 39 surgically resected specimens of IPMN that included 17 adenomas (IPMAs), 5 borderline tumors (IPMBs), 4 non-invasive carcinomas (non-invasive IPMCs), and 13 invasive carcinomas (invasive IPMCs). Immunostaining was performed according to the EnVision ChemMate method. The degree of maspin expression was scored and assessed according to the percentage and staining intensity of positive cells. RESULTS: Maspin expression was minimal in normal pancreatic duct epithelium, whereas in IPMNs, maspin was expressed in neoplasms of all stages. Maspin expression increased with increasing grade from IPMAs, IPMBs, to non-invasive IPMCs but decreased significantly in invasive IPMCs. No specific association between maspin expression and mucin type was found. Analysis of maspin expression with respect to clinicopathologic factors in cases of invasive IPMC revealed a greater extent of invasion in cases of low maspin expression and significantly fewer apoptotic cells in the tumor.CONCLUSIONS: Maspin was expressed at high levels in IPMNs at various stages from adenoma to invasive carcinoma, and our results suggest that maspin may be involved in the occurrence and progression of IPMN. In addition, our data suggest that the apoptosis-inducing action of maspin suppresses invasion and progression of IPMN.

Extent of surgical resections for intraductal papillary mucinous neoplasms

Intraductal papillary mucinous neoplasms(IPMNs) can involve the main pancreatic duct(MD-IPMNs) or its secondary branches(BD-IPMNs) in a segmental of multifocal/diffuse fashion.Growing evidence indicates that BDIPMNs are less likely to harbour cancer and in selected cases these lesions can be managed non operatively.For surgery,clarification is required on:(1) when to resect an IPMN;(2) which type of resection should be performed;and(3) how much pancreas should be resected.In recent years parenchyma-sparing resections as well as laparoscopic procedures have being performed more frequently by pancreatic surgeons in order to decrease the rate of postoperative pancreatic insufficiency and to minimize the surgical impact of these operations.However,oncological radicality is of paramount importance,and extended resections up to total pancreatectomy may be necessary in the setting of IPMNs.In this article the type and extension of surgical resections in patients with MD-IPMNs and BD-IPMNs are analyzed,evaluating perioperative and long-term outcomes.The role of standard and parenchyma-sparing resections is discussed as well as different strategies in the case of multifocal neoplasms.

molecular pathology of intraductal papillary mucinous neoplasms of the pancreas

Since the first description of intraductal papillary mucinous neoplasms(IPMNs)of the pancreas in the eighties,their identification has dramatically increased in the last decades,hand to hand with the improvements in diagnostic imaging and sampling techniques for the study of pancreatic diseases.However,the heterogeneity of IPMNs and their malignant potential make difficult the management of these lesions.The objective of this review is to identify the molecular characteristics of IPMNs in order to recognize potential markers for the discrimination of more aggressive IPMNs requiring surgical resection from benign IPMNs that could be observed.We briefly summarize recent research findings on the genetics and epigenetics of intraductal papillary mucinous neoplasms,identifying some genes,molecular mechanisms and cellular signaling pathways correlated to the pathogenesis of IPMNs and their progression to malignancy.The knowledge of molecular biology of IPMNs has impressively developed over the last few years.A great amount of genes functioning as oncogenes or tumor suppressor genes have been identified,in pancreatic juice or in blood or in the samples from the pancreatic resections,but further researches are required to use these informations for clinical intent,in order to better define the natural history of these diseases and to improve their management.

Diagnostic and therapeutic endoscopic approaches to intraductal papillary mucinous neoplasm

Pancreatic cystic lesions are increasingly identified on routine imaging.One specific lesion,known as intraductal papillary mucinous neoplasm(IPMN),is a mucinous,pancreatic lesion characterized by papillary cells projecting from the pancreatic ductal epithelium.The finding of mucin extruding from the ampulla is essentially pathognomonic for diagnosing these lesions.IPMNs are of particular interest due to their malignant potential.Lesions range from benign,adenomatous growths to highgrade dysplasia and invasive cancer.These mucinous lesions therefore require immediate attention to determine the probability of malignancy and whether observation or resection is the best management choice.Unresected lesions need long-term surveillance monitoring for malignant transformation.The accurate diagnosis of these lesions is particularly challenging due to the substantial similarities in morphology of pancreatic cystic lesions and limitations in current imaging technologies.Endoscopic evaluation of these lesions provides additional imaging,molecular,and histologic data to aid in the identification of IPMN and to determine treatment course.The aim of this article is to focus on the diagnostic and therapeutic endoscopic approaches to IPMN.

Imaging considerations in intraductal papillary mucinous neoplasms of the pancreas

With the widespread use of cross-sectional imaging,particularly computed tomography(CT) and magnetic resonance imaging(MRI),and the continuous improvement in the image quality of these techniques,the diagnosis of incidental pancreatic cysts has increased dramatically in the last decades.While the vast majority of these cysts are not clinically relevant,a small percentage of them will evolve into an invasive malignant tumor making their management challenging.Mucinous cystic neoplasms and intraductal papillary mucinous neoplasms(IPMN) are the most common pancreatic cystic lesions with malignant potential.Imaging findings on CT and MRI correlate tightly with the presence of malignant degeneration in these neoplasms.IPMN can be classified based on their distribution as main duct,branch duct or mixed type lesions.MRI is superior to CT in demonstrating the communication of a branch duct IPMN with the main pancreatic duct(MPD).Most branch duct lesions are benign whereas tumors involving the MPD are frequently associated with malignancy.The presence of solid nodules,thick enhancing walls and/or septae,a wide(> 1 cm) connection of a side-branch lesion with the MPD and the size of the tumor > 3 cm are indicative of malignancy in a branch and mixed type IPMN.A main pancreatic duct > 6 mm,a mural nodule > 3 mm and an abnormal attenuating area in the adjacent pancreatic parenchyma on CT correlates with malignant disease in main duct and mixed type IPMN.An accurate characterization of these neoplasms by imaging is thus crucial for selecting the best management options.In this article,we review the imaging findings of IPMN including imaging predictors of malignancy and surgical resectability.We also discuss follow-up strategies for patients with surgically resected IPMN and patients with incidental pancreatic cysts.

Extrapancreatic malignancies and intraductal papillary mucinous neoplasms of the pancreas

Over the last two decades multiple studies have demonstrated an increased incidence of additional malignancies in patients with intraductal papillary mucinous neoplasms(IPMNs).Additional malignancies have been identified in 10%-52% of patients with IPMNs.The majority of these additional cancers occur before or concurrent with the diagnosis of IPMN.The gastrointestinal tract is most commonly involved in secondary malignancies,with benign colon polyps and colon cancer commonly seen in western countries and gastric cancer commonly seen in Asian countries.Other extrapancreatic malignancies associated with IPMNs include benign and malignant esophageal neoplasms,gastrointestinal stromal tumors,carcinoid tumors,hepatobiliary cancers,breast cancers,prostate cancers,and lung cancers.There is no clear etiology for the development of secondary malignancies in patients with IPMN.Although population-based studies have shown different results from single institution studies regarding the exact incidence of additional primary cancers in IPMN patients,both have reached the same conclusion:there is a higher incidence of extrapancreatic malignancies in patients with IPMNs than in the general population.This f inding has signif icant clinical implications for both the initial evaluation and the subsequent long-term followup of patients with IPMNs.If a patient has not had recent colonoscopy,this should be performed during the evaluation of a newly diagnosed IPMN.Upper endoscopy should be performed in patients from Asian countries or for those who present with symptoms suggestive of upper gastrointestinal disease.Routine screening studies(breast and prostate) should be carried out as currently recommended for patient's age both before and after the diagnosis of IPMN.

Multiphase computed tomography radiomics of pancreatic intraductal papillary mucinous neoplasms to predict malignancy

BACKGROUND Intraductal papillary mucinous neoplasms(IPMNs)are non-invasive pancreatic precursor lesions that can potentially develop into invasive pancreatic ductal adenocarcinoma.Currently,the International Consensus Guidelines(ICG)for IPMNs provides the basis for evaluating suspected IPMNs on computed tomography(CT)imaging.Despite using the ICG,it remains challenging to accurately predict whether IPMNs harbor high grade or invasive disease which would warrant surgical resection.A supplementary quantitative radiological tool,radiomics,may improve diagnostic accuracy of radiological evaluation of IPMNs.We hypothesized that using CT whole lesion radiomics features in conjunction with the ICG could improve the diagnostic accuracy of predicting IPMN histology.AIM To evaluate whole lesion CT radiomic analysis of IPMNs for predicting malignant histology compared to International Consensus Guidelines.METHODS Fifty-one subjects who had pancreatic surgical resection at our institution with histology demonstrating IPMN and available preoperative CT imaging were included in this retrospective cohort.Whole lesion semi-automated segmentation was performed on each preoperative CT using Healthmyne software(Healthmyne,Madison,WI).Thirty-nine relevant radiomic features were extracted from each lesion on each available contrast phase.Univariate analysis of the 39 radiomics features was performed for each contrast phase and values were compared between malignant and benign IPMN groups using logistic regression.Conventional quantitative and qualitative CT measurements were also compared between groups,viaχ2(categorical)and Mann Whitney U(continuous)variables.RESULTS Twenty-nine subjects(15 males,age 71±9 years)with high grade or invasive tumor histology comprised the"malignant"cohort,while 22 subjects(11 males,age 70±7 years)with low grade tumor histology were included in the"benign"cohort.Radiomic analysis showed 18/39 precontrast,19/39 arterial phase,and 21/39 venous phase features differentiated malignant from benign IPMNs(P<0.05).Multivariate analysis including only ICG criteria yielded two significant variables:thickened and enhancing cyst wall and enhancing mural nodule<5 mm with an AUC(95%CI)of 0.817(0.709-0.926).Multivariable post contrast radiomics achieved an AUC(95%CI)of 0.87(0.767-0.974)for a model including arterial phase radiomics features and 0.834(0.716-0.953)for a model including venous phase radiomics features.Combined multivariable model including conventional variables and arterial phase radiomics features achieved an AUC(95%CI)of 0.93(0.85-1.0)with a 5-fold cross validation AUC of 0.90.CONCLUSION Multi-phase CT radiomics evaluation could play a role in improving predictive capability in diagnosing malignancy in IPMNs.Future larger studies may help determine the clinical significance of our findings.

Differential diagnosis of benign and malignant branch duct intraductal papillary mucinous neoplasm using contrastenhanced endoscopic ultrasonography

AIM: To elucidate the role of contrast-enhanced endoscopic ultrasonography(CE-EUS) in the diagnosis of branch duct intraductal papillary mucinous neoplasm(BD-IPMN).METHODS: A total of 50 patients diagnosed with BDIPMN by computed tomography(CT) and endoscopic ultrasonography(EUS) at our institute were included in this study. CE-EUS was performed when mural lesions were detected by EUS. The diagnostic accuracy for identifying mural nodules(MNs) was evaluated by CT, EUS, and EUS combined with CE-EUS. In the patients who underwent resection, the accuracy of measuring MN height with each imaging modality was compared. The cut-off values to diagnose malignant BD-IPMNs based on MN height for each imaging modality were determined using receiver operating characteristic curve analysis.RESULTS: Fifteen patients were diagnosed with BD-IPMN with MNs and underwent resection. The remaining 35 patients were diagnosed with BD-IPMN without MNs and underwent follow-up monitoring. The pathological findings revealed 14 cases with MNs and one case without. The accuracy for diagnosing MNs was 92% using CT and 72% using EUS; the diagnostic accuracy increased to 98% when EUS and CE-EUS were combined. The accuracy for measuring MN height significantly improved when using CE-EUS compared with using CT or EUS(median measurement error value, CT: 3.3 mm vs CE-EUS: 0.6 mm, P < 0.05; EUS: 2.1 mm vs CE-EUS: 0.6 mm, P < 0.01). A cut-off value of 8.8 mm for MN height as measured by CE-EUS improved the accuracy of diagnosing malignant BDIPMN to 93%. CONCLUSION: Using CE-EUS to measure MN height provides a highly accurate method for differentiating benign from malignant BD-IPMN.

Differentiating intraductal papillary mucinous neoplasms from other pancreatic cystic lesions

Intraductal papillary mucinous neoplasms(IPMN) can be difficult to distinguish from other cystic lesions of the pancreas.To understand better and discuss the current knowledge on this topic,the literature and the institutional experience at a large pancreatic disease center have been reviewed.A combination of preoperative demographic,historical,radiographic,laboratory data,as well as postoperative pathologic analyses can often distinguish IPMN from other lesions in the differential diagnosis.

Intraductal papillary mucinous neoplasm and the pancreatic incidentaloma

Asymptomatic pancreatic lesions(APL) are a commonly encountered problem in today's pancreatic surgical practices.Current literature regarding etiologies and incidence of APLs,particularly intraductal papillary mucinous neoplasm(IPMN),is presented.APLs constitute a wide spectrum of pathology(solid/cystic,benign/premalignant/malignant) but,overall,IPMN is now the most common diagnosis.The Sendai Guidelines and their function as a basis for risk stratification in branch duct IPMN are presented.The importance of traditionally analyzed cyst characteristics including size,presence of mucin or nodules and cyst fluid aspirate as indicators of malignancy is emphasized,noting also the potential correlation of main duct dilatation,thickened septae and elevated cyst fluid CEA with increased risk of malignancy.Current complication rates after resection of APLs are reviewed and found to be generally equivalent to those for symptomatic resections.A potential multidisciplinary treatment strategy is offered considering the costs of surgery versus repeated imaging or follow up endoscopy for these lesions.The decision for intervention is ultimately based on the Sendai Guidelines in the context of the individual patient.