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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

Pancreatic intraductal papillary mucinous neoplasms:Current diagnosis and management

Intraductal papillary mucinous neoplasms(IPMNs)represent approximately 1%of all pancreatic neoplasms and 25%of cystic neoplasms.They are divided into three types:main duct-IPMN(MD-IPPMN),branch duct-IPMN(BD-IPMN),and mixed type-IPMN.In this review,diagnostics,including clinical presentation and radiological investigations,were described.Magnetic resonance imaging is the most useful for most IPMNs.Management depends on the type and radiological features of IPMNs.Surgery is recommended for MD-IPMN.For BD-IPMN,management involves surgery or surveillance depending on the tumor size,cyst growth rate,solid components,main duct dilatation,high-grade dysplasia in cytology,the presence of symptoms(jaundice,new-onset diabetes,pancreatitis),and CA 19.9 serum level.The patient’s age and comorbidities should also be taken into consideration.Currently,there are different guidelines regarding the diagnosis and management of IPMNs.In this review,the following guidelines were presented:Sendai International Association of Pancreatology guidelines(2006),American Gastroenterological Association guidelines,revised international consensus Fukuoka guidelines(2012),revised international consensus Fukuoka guidelines(2017),and European evidence-based guidelines according to the European Study Group on Cystic Tumours of the Pancreas(2018).The Verona Evidence-Based Meeting 2020 was also presented and discussed.

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.

Imaging features of intraductal papillary mucinous neoplasms of the pancreas in multi-detector row computed tomography

AIM:To retrospectively evaluate the imaging features of pancreatic intraductal papillary mucinous neoplasms (IPMNs) in multi-detector row computed tomography (MDCT).METHODS: A total of 20 patients with pathologically-confirmed intraductal papillary mucinous neoplasms (IPMNs) were included in this study. Axial MDCT images combined with CT angiography (CTA) and multiplanar volume reformations (MPVR) or curved reformations (CR) were preoperatively acquired. Two radiologists (Tan L and Wang DB) reviewed all the images in consensus using an interactive picture archiving and communication system. The disputes in readings were resolved through consultation with a third experienced radiologist (Chen KM). Finally, the findings and diagnoses were compared with the pathologic results.RESULTS: The pathological study revealed 12 malignant IPMNs and eight benign IPMNs. The diameters of the cystic lesions and main pancreatic ducts (MPDs) were significantly larger in malignant IPMNs compared with those of the benign IPMNs (P<0.05). The combined-type IPMNs had a higher rate of malignancy than the other two types of IPMNs (P<0.05). Tumors with mural nodules and thick septa had a significantly higher incidence of malignancy than tumors without these features (P<0.05). Communication of side-branch IPMNs with the MPD was present in nine cases at pathologic examination. Seven of them were identified from CTA and MPVR or CR images. From comparison with the pathological diagnosis, the sensitivity, specificity, and accuracy of MDCT in characterizing the malignancy of IPMN of the pancreas were determined to be 100%, 87.5% and 95%, respectively.CONCLUSION: MDCT with CTA and MPVR or CR techniques can elucidate the imaging features of IPMNs and help predict the malignancy of these tumors.

Prognosis of invasive intraductal papillary mucinous neoplasms of the pancreas

Intraductal papillary mucinous neoplasms(IPMN) are mucin producing cystic neoplasms of the pancreas histologically classified as having non-invasive and invasive components.The five-year survival rates for non-invasive and associated invasive carcinoma are 90% and 40%,respectively in resected IPMN lesions.Invasive carcinoma within IPMN lesions can be further classified by histological subtype into colloid carcinoma and tubular carcinoma.Estimated five-year survival rates following resection of colloid carcinoma range from 57%-83% and estimated five-year survival following resection of tubular carcinoma range from 24%-55%.The difference in survival outcome between invasive colloid and tubular IPMN appears to be a function of disease biology,as patients with the tubular subtype tend to have larger tumors with a propensity for metastasis to regional lymph nodes.When matched to resected conventional pancreatic adenocarcinoma lesions by the Memorial Sloan Kettering Cancer Center pancreatic adenocarcinoma nomogram,the colloid carcinoma histological subtype has an improved estimated five-year survival outcome compared to conventional pancreatic adenocarcinoma,87% and 23%(P = 0.0001),respectively.Resected lesions with the tubular carcinoma subtype overall have a similar five-year survival outcome compared to conventional pancreatic adenocarcinoma.However,when these groups were stratified by regional lymph node status patients with negative regional lymph nodes and the tubular subtype experienced significantly better survival than patients with a similar nodal status and ductal adenocarcinoma with estimated five-year survival rates of 73% and 27%(P = 0.01),respectively.

Intraductal papillary mucinous neoplasms and other pancreatic cystic lesions

Pancreatic cystic neoplasms are being increasingly recognized, even in the absence of symptoms, in large part, due to markedly improved imaging modalities such as magnetic resonance imaging (MRI)/magnetic resonance cholangio pancreatography (MRCP) and computer tomography (CT) scanning. During the past 2 decades, better imaging of these cystic lesions has resulted in definition of different types, including pancreatic intraductal papillary mucinous neoplasms (IPMN). While IPMN represent only a distinct minority of all pancreatic cancers, they appear to be a relatively frequent neoplastic form of pancreatic cystic neoplasm. Moreover, IPMN have a much better outcome and prognosis compared to pancreatic ductal adenocarcinomas. Therefore, recognition of this entity is exceedingly important for the clinician involved in diagnosis and further evaluation of a potentially curable form of pancreatic cancer.

Endoscopic ultrasound in the diagnosis of pancreatic intraductal papillary mucinous neoplasms

Pancreatic cystic lesions are increasingly recognised due to the widespread use of different imaging modalities.Intraductal papillary mucinous neoplasms(IPMNs)of the pancreas represent a common,but also heterogeneous group of cystic tumors with a significant malignant potential.These neoplasms must be differentiated from other cystic tumors and properly classified into their different types,main-duct IPMNs vs branchduct IPMNs.These types have a different malignant potential and therefore,different treatment strategies need to be implemented.Endoscopic ultrasound(EUS)offers the highest resolution of the pancreas and can aid in the differential diagnosis,classification and differentiation between benign and malignant tumors.The addition of EUS fine-needle aspiration can supply further information by obtaining fluid for cytology,measurement of tumor markers and perhaps DNA analysis.Novel techniques,such as the use of contrast and sophisticated equipment,like intraductal probes can provide information regarding malignant features and extent of these neoplasms.Thus,EUS is a valuable tool in the diagnosis and appropriate management of these tumors.

Nomograms predicting long-term survival in patients with invasive intraductal papillary mucinous neoplasms of the pancreas: A population-based study

BACKGROUND There are few effective tools to predict survival in patients with invasive intraductal papillary mucinous neoplasms of the pancreas.AIM To develop comprehensive nomograms to individually estimate the survival outcome of patients with invasive intraductal papillary mucinous neoplasms of the pancreas.METHODS Data of 1219 patients with invasive intraductal papillary mucinous neoplasms after resection were extracted from the Surveillance,Epidemiology,and End Results database,and randomly divided into the training(n=853)and the validation(n=366)cohorts.Based on the Cox regression model,nomograms were constructed to predict overall survival and cancer-specific survival for an individual patient.The performance of the nomograms was measured according to discrimination,calibration,and clinical utility.Moreover,we compared the predictive accuracy of the nomograms with that of the traditional staging system.RESULTS In the training cohort,age,marital status,histological type,T stage,N stage,M stage,and chemotherapy were selected to construct nomograms.Compared with the American Joint Committee on Cancer 7th staging system,the nomograms were generally more discriminative.The nomograms passed the calibration steps by showing high consistency between actual probability and nomogram prediction.Categorial net classification improvements and integrated discrimination improvements suggested that the predictive accuracy of the nomograms exceeded that of the American Joint Committee on Cancer staging system.With respect to decision curve analyses,the nomograms exhibited more preferable net benefit gains than the staging system across a wide range of threshold probabilities.CONCLUSION The nomograms show improved predictive accuracy,discrimination capability,and clinical utility,which can be used as reliable tools for risk classification and treatment recommendations.

Localized type 1 autoimmune pancreatitis superimposed upon preexisting intraductal papillary mucinous neoplasms

A 70-year-old woman was found to have 2 cystic lesions in the head of the pancreas on abdominal ultrasonography during a routine medical examination.Endoscopic ultrasonography(EUS)and magnetic resonance cholangiopancreatography showed multilocular cysts in the head of the pancreas without dilation of the main pancreatic duct.The patient was followed-up semiannually with imaging studies for suspected branch duct-type intraductal papillary mucinous neoplasm(IPMN).At 3 years after initial presentation,hypoechoic lesions were observed around each pancreatic cyst by EUS.Diffusion-weighted imaging showed high-intensity regions corresponding to these lesions.Therefore,a diagnosis of invasive carcinoma derived from IPMN could not be excluded,and subtotal stomach-preserving pancreaticoduodenectomy was performed.The macroscopic examination of the surgical specimen showed whitish solid masses in the head of the pancreas,with multilocular cysts within each mass.Microscopically,each solid mass consisted of inflammatory cells such as lymphocytes and plasma cells.Furthermore,immunochemical staining revealed immunoglobulin G4-positive cells,and many obliterating phlebitides were observed.The cysts consisted of mucus-producing epithelial cells and showed a papillary growth pattern.Based on these findings,we diagnosed multiple localized type 1 autoimmune pancreatitis occurring only in the vicinity of the branch ducttype IPMN.