Fatal pancreatic fistula after laparoscopic distal pancreatectomy for intraductal papillary mucinous carcinoma with pancreaticobiliary maljunction and sphincterotomized papilla: a case report

Background

Pancreatic juice is constantly activated by contaminated bile in patients with pancreaticobiliary maljunction (PBM). Here, we report a case of laparoscopic distal pancreatectomy for a patient with PBM and sphincterotomized papilla, resulting in fatal pancreatic fistula.

Case presentation

A 79-year-old man was diagnosed with pancreatic intraductal papillary mucinous neoplasm and common bile duct stones. Endoscopic sphincterotomy was performed prior to surgery. The pancreatic duct was simultaneously visualized when the contrast agent was injected into the common bile duct. Sudden bleeding was observed from the abdominal drain on postoperative day (POD) 6. Emergent stent graft placement and coil embolization were performed for bleeding from the splenic artery. On POD 9, the drainage fluid changed to yellowish in color with bile contamination. For internal drainage of the digestive fluid, endoscopic retrograde biliary tube and pancreatic drainage tube were placed. On POD 24, second emergent coil embolization was performed for bleeding from the left gastric artery. On POD 25, open abdominal drainage was performed. On POD 32, third emergent coil embolization was performed for bleeding from the gastroduodenal artery. Subsequently, remnant pancreatic resection was performed. On POD 39, massive bleeding was again observed from the abdominal drain. Emergency arterial portography revealed bleeding in the right wall of the superior mesenteric vein. The patient died of hemorrhagic shock on the same day.

Conclusions

The extreme risk of severe pancreatic fistula after distal pancreatectomy should be considered in patients with PBM and sphincterotomized papilla. In this extraordinary situation, surgeons should promptly decide whether to resect the remnant pancreas to prevent losing the patient.

Computed tomography nomogram to predict a high-risk intraductal papillary mucinous neoplasm of the pancreas

OBJECTIVE

The intraductal papillary mucinous neoplasm (IPMN) of the pancreas is regarded as a precursor to pancreatic cancer; this study aimed to develop and validate a model based on CT characteristics for the non-invasive prediction of the high-risk IPMN of the pancreas.

MATERIALS AND METHODS

In this retrospective study, all patients underwent multidetector CT and surgical resection. A prediction model was developed based on a training set consisting of 136 patients with low-risk IPMN and 85 patients with high-risk IPMN between October 2012 and April 2019, and a multivariable logistic regression model was adopted to establish a nomogram. The nomogram performance was determined by its discrimination, calibration, and clinical usefulness. The model was validated in 80 consecutive patients between May 2019 and April 2020, of which 47 and 33 patients had low-risk and high-risk IPMNs, respectively.

RESULTS

The multivariable logistic regression model of CT characteristics included the enhancing mural nodule size, the main pancreatic duct (MPD) diameter, the abrupt change in caliber of the MPD with distal pancreatic atrophy, cyst size, thickened enhancing cyst wall, and the presence of lymphadenopathy. The individualized prediction nomogram using these predictors of the high-risk IPMN achieved an area under the curve (AUC) of 0.92 (95% CI 0.88-0.95) in the training set and 0.87 (95% CI 0.79-0.95) in the validation set. The decision curve analysis demonstrated that the nomogram was clinically useful.

CONCLUSION

The CT nomogram, which is a non-invasive predictive tool, can preoperatively predict the risk of malignant IPMN and help identify patients who require a surgical procedure.

A case of ectopic pancreas of the stomach accompanied by intraductal papillary mucinous neoplasm with GNAS mutation

BACKGROUND

Ectopic pancreas is basically a benign disease and is not always necessary to be removed. However, all types of neoplasms occurring in the normal pancreas such as ductal adenocarcinomas and intraductal papillary mucinous neoplasms (IPMNs) may develop even within ectopic pancreas. We recently encountered an extremely rare case of ectopic pancreas in the gastric antrum associated with IPMN possessing a GNAS mutation.

CASE PRESENTATION

A 71-year-old Japanese woman complained of epigastric pain. Computed tomography and upper gastrointestinal endoscopy showed an intramural cystic mass in the antrum of the stomach. Endoscopic ultrasound-guided fine needle aspiration (EUS-FNA) biopsy did not give a definitive diagnosis, and the patient underwent resection of the lesion. Histology of the resected specimen showed that the gastric intramural lesion was ectopic pancreas. Moreover, the lesion contained dilated duct components with tubulo-villous epithelial proliferation consistent with pancreatic IPMN. Since the covering epithelial cells had highly atypical nuclei, the lesion was diagnosed as IPMN with high grade dysplasia. Immunohistochemistry showed that the IPMN component showed to be MUC2-, MUC5AC-, and CDX2-positive but MUC1- and MUC6-negative. Mutational analyses using genomic DNA revealed that the IPMN component had a mutation of GNAS at exon 8 (Arg201Cys).

CONCLUSION

We finally diagnosed this case as gastric ectopic pancreas accompanied by intestinal type IPMN with high grade dysplasia possessing GNAS mutation. Although there were 17 cases of ectopic pancreas with IPMN including 6 cases of gastric ones reported in the English literature, this is the first case of ectopic pancreas with IPMN which was proved to have GNAS mutation. Intimate preoperative examinations including imaging analyses and EUS-FNA biopsy/cytology are recommended to decide whether the lesion has to be resected or not even if they are not effective for getting the right diagnosis.

A meta-analysis: incidental intraductal papillary mucinous neoplasm and extra-pancreatic malignancy

INTRODUCTION

Meta-analysis aimed to quantify the relationship between intraductal papillary mucinous neoplasm (IPMN) and increased incidence of extra-pancreatic malignancy (EPM) previously reported in qualitative observational cohort studies.

METHODS

Study protocol was registered with PROSPERO (CRD42020169614) and conducted to the Meta-analysis Of Observational Studies in Epidemiology and systematic review reported with Preferred Reporting Items for Systematic Reviews and Meta-Analyses, Assessing the Methodological Quality of Systematic Reviews guidelines.

RESULTS

Sixteen studies (total of 8240 patients) were included in the pooled, and 7399 patients in the subgroup meta-analyses. The odds ratio (OR) for any EPM in the presence of IPMN was 57.9 (95% confidence interval 40.5-82.7), fixed effects, I² = 59% (p < 0.0014). Subgroup analysis for any gastrointestinal EPM (i.e. oesophagus, stomach, colon and rectum) in the presence of an IPMN estimated an overall OR of 12.9 (95% confidence interval 8.8-19.0), fixed effects, I² = 64% (p < 0.0004).

CONCLUSION

Patients with an IPMN are categorically at increased risk for a higher incidence of EPM and particularly the odds of a gastrointestinal malignancy are also increased in comparison with the general population. We advocate that patients presenting with an IPMN should be considered for gastrointestinal screening including colonoscopy, upper gastrointestinal endoscopy or computed tomography.

Magnetic resonance imaging-derived fat fraction predicts risk of malignancy in intraductal papillary mucinous neoplasm

PURPOSE

Assess the relationship between MRI-derived pancreatic fat fraction and risk of malignancy in intraductal papillary mucinous neoplasm (IPMN).

METHODS

MRIs of patients with IPMN who underwent pancreaticoduodenectomy were analyzed. IPMN with low-grade dysplasia (n = 29) were categorized as low-risk while IPMN at high risk of malignancy consisted of those with high-grade dysplasia/invasive carcinoma (n = 33). Pancreatic fat-fraction (FFmean) was measured using the 2-point Dixon-method. Images were evaluated for the high-risk stigmata and worrisome features according to the revised 2017 Fukuoka consensus criteria. Data on serum CA19-9, Diabetes Mellitus (DM) status, body mass index (BMI), and histological chronic pancreatitis were obtained.

RESULTS

A significant difference in FFmean was found between the high-risk IPMN (11.45%) and low-risk IPMN (9.95%) groups (p = 0.027). Serum CA19-9 level (p = 0.021), presence of cyst wall enhancement (p = 0.029), and solid mass (p = 0.008) were significantly associated with high-risk IPMN. There was a significant correlation between FFmean and mural nodule size (r = 0.36, p ˂ 0.01), type 2 DM (r = 0.34, p ˂ 0.01), age (r = 0.31, p ˂ 0.05), serum CA 19-9 (r = 0.30, p ˂ 0.05), cyst diameter (r = 0.30, p ˂ 0.05), and main pancreatic duct diameter (r = 0.26, p ˂ 0.05). Regression analysis revealed FFmean (OR 1.103, p = 0.035) as an independent predictive variable of high-risk IPMN.

CONCLUSION

FFmean is significantly associated with high-risk IPMN and an independent predictor of IPMN malignant risk. FFmean may have clinical utility as a biomarker to complement the current IPMN treatment algorithm and improve clinical decision making regarding the need for surgical resection or surveillance.

Outcome after resection for invasive intraductal papillary mucinous neoplasia is similar to conventional pancreatic ductal adenocarcinoma

BACKGROUND/OBJECTIVES

Resections for intraductal papillary mucinous neoplasm (IPMN) have increased last decades. Overall survival (OS) for conventional pancreatic ductal adenocarcinoma (PDAC) is well known but OS for invasive IPMN (inv-IPMN) is not as conclusive. This study aims to elucidate potential differences in clinicopathology and OS between these tumor types and to investigate if the raised number of resections have affected outcome.

METHODS

Consecutive patients ≥18 years of age resected for inv-IPMN and PDAC at Karolinska University Hospital between 2009 and 2018 were included. Clinicopathological variables were analyzed in multivariable regression models. Outcome was assessed calculating two-year OS, estimating OS using the Kaplan-Meier model and comparing survival functions with log-rank test.

RESULTS

513 patients were included, 122 with inv-IPMN and 391 with PDAC. During the study period both the proportion resected inv-IPMN and two-year OS, irrespective of tumor type, increased (2.5%-45%; p < 0.001 and 44%-57%; p = 0.005 respectively). In Kaplan-Meier survival analysis inv-IPMN had more favorable median OS (mOS) compared to PDAC (33.6 months vs 19.3 months, p = 0.001). However, in multivariable Cox Regression analysis, tumor type was not a predictor for death, but so were resection period, tumor subtype and N-stage (all p < 0.001).

CONCLUSION

In this large single center observational cohort study, inv-IPMN seemed to have favorable survival outcome compared to PDAC, but after adjusting for predictors for death this benefit vanished. The combination of a pronounced increase in resected inv-IPMN and a concurrent hazard abatement for death within 2 years during the study period proved to be a principal factor.

A case of intraductal papillary mucinous neoplasm developing in the native pancreas after pancreas transplantation treated by total pancreatectomy

Post-transplant patients reportedly have a higher risk of de novo neoplasms. However, intraductal papillary mucinous neoplasm (IPMN) of the native pancreas after pancreas transplantation (PTx) has not been well investigated. The choice of treatment, especially invasive treatment, for de novo neoplasms in transplant patients should consider their impaired immunity. In this context, we present a case of IPMN developing in the native pancreas of a PTx patient. A 53-year-old man underwent a follow-up abdominal computed tomography scan 6 years after a simultaneous pancreas-kidney transplant for type 1 diabetes mellitus with end-stage diabetic nephropathy requiring hemodialysis. The scan revealed IPMN in the pancreas head; an enhancing internal solid component suggested a high risk of malignancy, indicating surgical resection. Partial pancreatectomy or pancreaticoduodenectomy was anatomically indicated, but considering the insulin-secreting ability of the transplanted pancreas and the potential high risk of postoperative pancreatic fistula due to immune impairment after partial pancreatectomy, total pancreatectomy (TP) was performed. The patient is alive with good pancreas graft function, no signs of indigestion for 18 months after TP, and no evidence of IPMN recurrence. This report should help clinicians characterize de novo IPMN in the native pancreas and determine IPMN therapeutic options for transplant patients.

An intraductal papillary mucinous neoplasm associated tubular adenocarcinoma with sarcomatoid component: A case report

Intraductal papillary mucinous neoplasms (IPMNs) of the pancreas are a risk factor for the development of adenocarcinoma. However, the presence of a component of sarcomatoid carcinoma in the malignant tumor has rarely been described in the literature. A 30-year-old Chinese woman was admitted to our hospital with vague abdominal pain and a poor appetite for 2 months. Computed tomography revealed a huge, unilocular, solid-cystic mass in the pancreatic body, and tail. The patient underwent an en bloc resection of the distal pancreatic tumor with splenectomy and regional lymphadenectomy. Pathologic examination revealed an IPMN associated tubular adenocarcinoma containing a component of sarcomatoid (spindle-shaped cell) carcinoma. Immunohistochemical results revealed that the mononuclear spindle-shaped cells were positive for both pan-cytokeratin and vimentin. There was no evidence of perineural or vascular infiltration, lymph nodal metastasis, or positive surgical margins. The patient developed local recurrence 3 months after surgery for which she received chemoradiotherapy at another hospital. Distant metastases were detected 6 months after the surgery and the patient expired 9 months after surgical resection. We concluded that the presence of sarcomatoid change in IPMN-associated pancreatic adenocarcinoma may indicate poor prognosis.

Updates in diagnosis and management of pancreatic cysts

Incidental pancreatic cysts are commonly encountered with some cysts having malignant potential. The most common pancreatic cystic neoplasms include serous cystadenoma, mucinous cystic neoplasm and intraductal papillary mucinous neoplasm. Risk stratifying pancreatic cysts is important in deciding whether patients may benefit from endoscopic ultrasound (EUS) or surgical resection. Surgery should be reserved for patients with malignant cysts or cysts at high risk for developing malignancy as suggested by various risk features including solid mass, nodule and dilated main pancreatic duct. EUS may supplement magnetic resonance imaging findings for cysts that remain indeterminate or have concerning features on imaging. Various cyst fluid markers including carcinoembryonic antigen, glucose, amylase, cytology, and DNA markers help distinguish mucinous from nonmucinous cysts. This review will guide the practicing gastroenterologist in how to evaluate incidental pancreatic cysts and when to consider referral for EUS or surgery. For presumed low risk cysts, surveillance strategies will be discussed. Managing pancreatic cysts requires an individualized approach that is directed by the various guidelines.

Diagnosis and treatment of hemosuccus pancreaticus induced by intraductal papillary mucinous neoplasm: a case report and review of the literature

Determining the cause of gastrointestinal bleeding is critical to determining appropriate treatment. Upper gastrointestinal bleeding from the pancreas, referred to hemosuccus pancreaticus, is a rare entity that can cause massive and life-threatening bleeding. Diagnosis remains challenging, and the mortality rate of hemosuccus pancreaticus remains high, ranging from 9.6%–90%. In this article, we present a case that was successfully diagnosed and treated at the Department of General Surgery, Hanoi Medical University Hospital, and a review of the available literature regarding this rare disease.

A case report of gallbladder cancer and pancreas cystic neoplasm associated with pancreaticobiliary maljunction

INTRODUCTION AND IMPORTANCE

Pancreaticobiliary maljunction (PBM) is a rare congenital anomaly that is frequently associated with carcinoma of the biliary tract. However, there is still no clear evidence that PBM is associated with pancreatic tumors. Here we describe a case of gallbladder cancer and intraductal papillary mucinous neoplasm (IPMN) that is associated with PBM.

CASE PRESENTATION

A 72-year-old man underwent a cholecystectomy with hepatectomy (S4a + S5) and regional lymph node dissection for gallbladder adenocarcinoma invading the front lobe branch of the hepatic artery. A pylorus-preserving pancreaticodudenectomy was also performed for pancreatic IPMN.

CLINICAL DISCUSSION

Presence of mucin type 6 (MUC6) -positive pyloric gland metaplasia in both the dilated pancreatic duct and the gallbladder background mucosa suggests that pancreatic IPMN and gallbladder cancer may have a common phenotypic origin. Additionally, analysis of 41 reported cases of pancreatic cancer associated with PBM revealed that in all metachronous multiple cancer cases, biliary tract cancer preceded the pancreatic cancer with congenital biliary dilatation accompanied by PBM. The analysis also revealed an increased proportion of pancreatic cancer cases with PBM in patients who had not undergone a flow diversion procedure located in pancreatic head.

CONCLUSION

We show an interesting relationship between pancreatic/gallbladder cancer and PBM. More comprehensive evaluations of the whole pancreaticobiliary system in follow-up of patients with PBM is required to understand the full extent of this relationship.

Use of artificial intelligence in endoscopic ultrasound evaluation of pancreatic pathologies

The application of artificial intelligence (AI) using deep learning and machine learning approaches in modern medicine is rapidly expanding. Within the field of Gastroenterology, AI is being evaluated across a breadth of clinical and diagnostic applications including identification of pathology, differentiation of disease processes, and even automated procedure report generation. Many pancreatic pathologies can have overlapping features creating a diagnostic dilemma that provides a window for AI-assisted improvement in current evaluation and diagnosis, particularly using endoscopic ultrasound. This topic highlight will review the basics of AI, history of AI in gastrointestinal endoscopy, and prospects for AI in the evaluation of autoimmune pancreatitis, pancreatic ductal adenocarcinoma, chronic pancreatitis and intraductal papillary mucinous neoplasm.

Molecular alterations in pancreatic tumors

Genetic alterations in pancreatic tumors can usually be classified in: (1) Mutational activation of oncogenes; (2) Inactivation of tumor suppressor genes; and (3) Inactivation of genome maintenance genes controlling the repair of DNA damage. Endoscopic ultrasound-guided fine-needle aspiration has improved pre-operative diagnosis, but the management of patients with a pancreatic lesion is still challenging. Molecular testing could help mainly in solving these “inconclusive” specimens. The introduction of multi-gene analysis approaches, such as next-generation sequencing, has provided a lot of useful information on the molecular characterization of pancreatic tumors. Different types of pancreatic tumors (e.g., pancreatic ductal adenocarcinomas, intraductal papillary mucinous neoplasms, solid pseudopapillary tumors) are characterized by specific molecular alterations. The aim of this review is to summarize the main molecular alterations found in pancreatic tumors.

Pathology of intraductal papillary mucinous neoplasms

BACKGROUND

Intraductal papillary mucinous neoplasms (IPMNs) represent a unique opportunity to treat and prevent a curable neoplasm before it has the chance to progress to incurable cancer. This prospect, however, has to be balanced with the real risk of over treating patients with lesions that would, in fact, never progress during the life of the patient.

PURPOSE

Informed clinical decisions in the treatment of IPMNs are first and foremost based on a deep understanding of the pathology of these lesions.

CONCLUSIONS

Here we review the pathology of IPMNs, with an emphasis on the clinical relevance of the important features that characterize these lesions.

Histopathological evaluation of resected intraductal papillary mucinous neoplasms reveals distinct patterns of invasion in associated carcinomas

Invasive intraductal papillary mucinous neoplasms (inv-IPMNs) have a better prognosis than regular pancreatic ductal adenocarcinoma (PDAC), but no association with status of surgical margins and microscopic infiltration patterns has previously been described. The aim of this study is to review patterns of invasion and the predictive value of clinical guidelines in terms of rates of resection of high-grade dysplasia (HGD) and cancer among intraductal papillary mucinous neoplasms (IPMNs). Consecutively, resected IPMNs between 2011 and 2017 were analyzed. Data were obtained from a prospectively maintained database. A total of 132 patients were identified. Out of these, 38 patients with inv-IPMNs, initially identified as solid lesions suspicious of cancer, were compared with a control group of 101 patients with ordinary PDAC. Lower rates of vascular invasion, perineural invasion, lymph node metastasis, advanced T stage, and R1 status were characteristic of the inv-IPMNs in addition to better overall survival (OS) for a low tumor stage. Furthermore, as novel findings, the PDACs presented with resection margin involvement of 3 or more positive margins (31.3% vs. 9.5%, p = 0.044), associated with poor OS. Of the patients presenting as pT3, the inv-IPMN less often invaded more than one extrapancreatic anatomical structure (40.1% vs. 63.9%, p = 0.03). Regarding the predictive value of clinical guidelines, the frequency of resected HGD in IPMNs with high-risk stigmata (n = 54) and IPMNs with worrisome features was 30.7%, and the frequency of invasive carcinoma was 5.7%. In conclusion, we report a low resection rate of high-risk IPMNs and present novel findings describing inv-IPMNs as a less infiltrative phenotype compared with regular PDAC.

Long-Term Quality of Life after Pancreatic Surgery for Intraductal Papillary Mucinous Neoplasm

INTRODUCTION

Intraductal papillary mucinous neoplasms (IPMNs) represent the most common precancerous cystic lesions of the pancreas. The aim of our study was to investigate if resection for non-invasive IPMNs alters quality of life (QoL) in a long-term follow-up.

METHODS

Patients (n = 50) included in the analysis were diagnosed and resected from 2010 to 2016. QoL was assessed at a median of 5.5 years after resection. At that point in time, the current QoL as well as the QoL before resection was evaluated retrospectively. The standardised European Organisation for Research and Treatment of Cancer Quality of Life Questionnaire for Pancreatic Cancer (EORTC QLQ - PAN26) was applied for the QoL assessment.

RESULTS

After a median of 66 months postoperatively, the total QoL score significantly worsened (92.13 vs. 88.04, p = 0.020, maximum achievable score = 100) for patients (median age at surgery 68.0 years), mostly due to digestive symptoms. During the same follow-up period, median Eastern Cooperative Oncology Group (ECOG) performance status did not worsen (p = 0.003).

CONCLUSIONS

Long-term QoL statistically significantly worsened after pancreatic resection for IPMN. The extent of worsening, however, was small, and QoL still remained excellent. Therefore, resection in cases of IPMN is appropriate, if indicated carefully.

Intraductal papillary mucinous neoplasm (IPMN) of the pancreas: recommendations for Standardized Imaging and Reporting from the Society of Abdominal Radiology IPMN disease focused panel

There have been many publications detailing imaging features of malignant transformation of intraductal papillary mucinous neoplasms (IPMN), management and recommendations for imaging follow-up of diagnosed or presumed IPMN. However, there is no consensus on several practical aspects of imaging IPMN that could serve as a clinical guide for radiologists and enable future data mining for research. These aspects include how to measure IPMN, define reporting terminology, standardize reporting and unify guidelines for surveillance. The Society of Abdominal Radiology (SAR) created multiple Disease-Focused Panels (DFP) comprised multidisciplinary panel members who focus on a particular disease, with the goal to develop ways for radiologists to improve patient care, education, and research. DFP members met to identify the current controversies and limitations of imaging pancreatic IPMN. This paper aims to provide a practical review of the key imaging characteristics of IPMN for trainees and practicing radiologists, to guide uniformity of performance and interpretation of surveillance imaging studies, and to improve communication with clinicians by providing a lexicon and reporting template based on the experience of the SAR-DFP panel members.

Endoscopic ultrasonography findings of pancreatic parenchyma for predicting subtypes of intraductal papillary mucinous neoplasms

BACKGROUND AND AIMS

The subtypes of intraductal papillary mucinous neoplasms (IPMNs) are closely associated with the clinicopathological behavior and recurrence after surgical resection. However, there are no established non-invasive methods to confirm the subtypes of IPMNs without surgery. The aim of this study is to predict the subtypes of IPMNs using the findings of endoscopic ultrasonography (EUS).

METHODS

Sixty-two consecutive patients with IPMNs who underwent EUS before surgery were retrospectively reviewed. The following EUS findings were analyzed and their relationship with the subtypes was evaluated: diameter of the main pancreatic duct, cyst size, number of cysts, height of mural nodule, early chronic pancreatitis (CP) finding, fatty parenchyma and atrophic parenchyma.

RESULTS

The subtypes of IPMNs were as follows: gastric (G)-type 38 (61%), intestinal (I) -type 14 (23%) and pancreatobiliary (PB) -type 10 (16%). Fatty parenchyma was significantly associated with G-type (P < 0.0001). Early CP findings ≥2 and atrophic parenchyma were significantly correlated with I-type (P < 0.0001). PB-type was significantly associated with pancreatic parenchyma without early CP findings or fatty degeneration in comparison to the other subtypes (P < 0.0001). Using the above characteristic EUS findings, the sensitivity, specificity, and accuracy were as follows: 63%, 92% and 74%, respectively, in G-type, 57%, 96% and 87% in I-type, and 90%, 94% and 94% in PB-type.

CONCLUSIONS

The evaluation of EUS findings, especially focused on the pancreatic parenchyma, has the potential to predict the subtypes of IPMN.

Radiomic nomogram based on MRI to predict grade of branching type intraductal papillary mucinous neoplasms of the pancreas: a multicenter study

Background

Accurate diagnosis of high-grade branching type intraductal papillary mucinous neoplasms (BD-IPMNs) is challenging in clinical setting. We aimed to construct and validate a nomogram combining clinical characteristics and radiomic features for the preoperative prediction of low and high-grade in BD-IPMNs.

Methods

Two hundred and two patients from three medical centers were enrolled. The high-grade BD-IPMN group comprised patients with high-grade dysplasia and invasive carcinoma in BD-IPMN (n = 50). The training cohort comprised patients from the first medical center (n = 103), and the external independent validation cohorts comprised patients from the second and third medical centers (n = 48 and 51). Within 3 months prior to surgery, all patients were subjected to magnetic resonance examination. The volume of interest was delineated on T1-weighted (T1-w) imaging, T2-weighted (T2-w) imaging, and contrast-enhanced T1-weighted (CET1-w) imaging, respectively, on each tumor slice. Quantitative image features were extracted using MITK software (G.E.). The Mann-Whitney U test or independent-sample t-test, and LASSO regression, were applied for data dimension reduction, after which a radiomic signature was constructed for grade assessment. Based on the training cohort, we developed a combined nomogram model incorporating clinical variables and the radiomic signature. Decision curve analysis (DCA), a receiver operating characteristic curve (ROC), a calibration curve, and the area under the ROC curve (AUC) were used to evaluate the utility of the constructed model based on the external independent validation cohorts.

Results

To predict tumor grade, we developed a nine-feature-combined radiomic signature. For the radiomic signature, the AUC values of high-grade disease were 0.836 in the training cohort, 0.811 in external validation cohort 1, and 0.822 in external validation cohort 2. The CA19–9 level and main pancreatic duct size were identified as independent parameters of high-grade of BD-IPMNs using multivariate logistic regression analysis. The CA19–9 level and main pancreatic duct size were then used to construct the radiomic nomogram. Using the radiomic nomogram, the high-grade disease-associated AUC values were 0.903 (training cohort), 0.884 (external validation cohort 1), and 0.876 (external validation cohort 2). The clinical utility of the developed nomogram was verified using the calibration curve and DCA.

Conclusions

The developed radiomic nomogram model could effectively distinguish high-grade patients with BD-IPMNs preoperatively. This preoperative identification might improve treatment methods and promote personalized therapy in patients with BD-IPMNs.

Supplementary Information

The online version contains supplementary material available at 10.1186/s40644-021-00395-6.

Clinical outcome of conservatively managed pancreatic intraductal papillary mucinous neoplasms with mural nodules and main duct dilation

BACKGROUND

Surgical resection of intraductal papillary mucinous neoplasm (IPMN) is strongly recommended for patients exhibiting high-risk stigmata (HRS). However, determining surgical indications for elderly patients with comorbidities is challenging, as clinical outcomes are not well characterized. This multicenter observational study elucidated the clinical outcomes of patients with IPMN exhibiting HRS who did not undergo surgery.

METHODS

This study enrolled 101 IPMN patients exhibiting HRS with follow-up observations at 11 hospitals in Japan (2011-2016). The median observation period was 37 months (maximum: 86 months). Primary outcomes were estimated 5-year overall survival (OS) and disease-specific survival (DSS). Survival was also stratified based on HRS features.

RESULTS

Of 101 patients, 32 (31.7%) had the main pancreatic duct (MPD) measuring ≥ 10 mm and 80 (79.2%) had mural nodules measuring ≥ 5 mm. The estimated 5-year OS and DSS were 74% and 91%, respectively. In the stratified analysis, the co-presence of MPD ≥ 10 mm and mural nodules ≥ 5 mm or mural nodule ≥ 10 mm were related to worse 5-year DSS (MPD ≥ 10 mm and mural nodules ≥ 5 mm vs other characteristics: 60% vs 95%, log-rank test: p = 0.049; mural nodules ≥ 10 mm vs < 10 mm: 77% vs 95%, log-rank test: p = 0.003).

CONCLUSIONS

The estimated 5-year DSS of conservatively managed IPMN patients with mural nodules and main duct dilation was 91%. Only IPMN patients with plural HRS or large nodule formation might have an increased mortality risk. This is an important insight that can help facilitate appropriate clinical decision-making, especially in the elderly or high-surgical risk IPMN patients.

A case of endoscopic ultrasound-guided hepaticogastrostomy for obstructive jaundice caused by intraductal papillary mucinous neoplasm-associated pancreatobiliary fistula

Intraductal papillary mucinous neoplasm (IPMN) sometimes forms fistulas with other organs due to high pressure of pancreatic duct filled with huge amount of mucus. Pancreatobiliary fistula may cause obstructive jaundice due to the mucus and it is hard to manage the jaundice by endoscopic biliary stenting because of high viscosity of the bile. We report a case of IPMN with pancreatobiliary fistula managed by endoscopic ultrasound (EUS)-guided hepaticogastrostomy (HGS). The patient was 87 years old and presented with obstructive jaundice. As a transpapillary biliary stent was considered to have a risk of migration due to the absence of bile duct stenosis, a nasobiliary catheter was placed as an initial drainage. However, the catheter was frequently obstructed by mucus. The patient was intolerable for surgery because of his age. Considering the intrahepatic bile was serous, EUS-HGS was performed and jaundice improved successfully. This case study revealed that EUS-HGS might be a therapeutic option for obstructive jaundice caused by an IPMN-associated pancreatobiliary fistula.

Pancreatic cancer pathology viewed in the light of evolution

One way to understand ductal adenocarcinoma of the pancreas (pancreatic cancer) is to view it as unimaginably large numbers of evolving living organisms interacting with their environment. This “evolutionary view” creates both expected and surprising perspectives in all stages of neoplastic progression. Advances in the field will require greater attention to this critical evolutionary prospective.

Triple threat: pancreatic cystic lesion presenting with spontaneous hemorrhage is found to harbor three distinct neoplasms

Background

Pancreatic serous cystadenoma (SCA) is a benign, cystic lesion with an indolent growth pattern. Complications such as spontaneous hemorrhage or malignant transformation from SCA are extremely rare. Our case report describes an unusual presentation of a patient with a previously diagnosed SCA, made unique by the presence of three separate neoplasms in the final specimen.

Case presentation

A 74-year-old male with a previous diagnosis of SCA presented emergently with epigastric pain and non-bilious vomiting. Laboratory results were notable for a hemoglobin of 8.3 g/dl. CT scan of the abdomen demonstrated a complex, solid-cystic mass in the pancreatic head with a large hematoma and questionable focus of active hemorrhage. Surgical resection was recommended due to the risk of malignancy, possibility of re-bleeding, and symptoms of severe duodenal compression. Pancreaticoduodenectomy was performed, and final pathology demonstrated three separate neoplasms: serous cystadenoma, intraductal papillary mucinous neoplasm, and neuroendocrine tumor.

Conclusion

While pancreatic SCA are benign tumors that can be observed safely in the majority of cases, surgical intervention is often indicated in patients with large, symptomatic cysts or when diagnosis is unclear. When undergoing surveillance, it is crucial for both the patient and the care team to be aware of the possibility of rare, but life-threatening complications, such as hemorrhage. Likewise, the possibility of misdiagnosis or concurrent neoplasia should be considered.

Papillary Neoplasms of the Salivary Duct System: A Review

Papillary lesions of the salivary duct systems are uncommon. They encompass a heterogeneous group of benign, intermediate, and potentially aggressive neoplasms. With a few exceptions, historical descriptive terms such as papillary adenocarcinoma, papillary cystadenocarcinoma, and papillary adenoma are being replaced by defined entities, at same time acknowledging the papillary features as a histologic pattern. The evolving genetic landscape of these lesions increasingly permits their reproducible categorization. This article discusses those papillary proliferations encountered in the salivary glands with a focus on intraductal papillary mucinous neoplasms and cystadenomas. Intraductal carcinomas and sialadenoma papilliferum are addressed in separate articles in this issue.

Chronic inflammatory changes and oxidative stress in the background of "pancreatic ductal adenocarcinoma concomitant with intraductal papillary mucinous neoplasm"

Cases of "pancreatic ductal adenocarcinoma (PDAC) concomitant with intraductal papillary mucinous neoplasm" (IPMN) have multiple PDAC lesions more frequently than cases of "PDAC without IPMN". However, the mechanism of carcinogenesis in this former disease category remains unknown. The main objective of this work was thus to investigate the effects of chronic inflammation on carcinogenesis in PDAC cases. We selected 31 "PDAC concomitant with IPMN" patients and 58 "PDAC without IPMN" patients and pathologically evaluated their background pancreatic parenchyma. Fibrosis and inflammation scores of background pancreas were higher in "PDAC concomitant with IPMN" than in "PDAC without IPMN" (P < 0.0001 and P < 0.0001, respectively), whereas the fatty infiltration score of background pancreas was high in "PDAC without IPMN" (P = 0.0024). Immunohistochemically, the expression of 8-hydroxy-2'-deoxyguanosine (8-OHDG), an oxidative stress marker, in the background pancreas was high in "PDAC concomitant with IPMN" compared with that in "PDAC without IPMN" (P < 0.0001). Chronic inflammation activates oxidative stress in tissue throughout the pancreas and probably confers susceptibility to tumorigenesis in "PDAC concomitant with IPMN".

Changing trends in the clinicopathological features, practices and outcomes in the surgical management for cystic lesions of the pancreas and impact of the international guidelines: Single institution experience with 462 cases between 1995-2018

INTRODUCTION

The impact on clinical practice of the international guidelines including the Sendai Guidelines (SG06) and Fukuoka Guidelines (FG12) on the management of cystic lesions of the pancreas (CLP) has not been well-studied. The primary aim was to examine the changing trends and outcomes in the surgical management of CLP in our institution over time and to determine the impact of these guidelines on our institution practice.

METHODS

462 patients with surgically-treated CLP were retrospectively reviewed and classified under the 2 guidelines. The cohort was divided into 3 time periods: 1998-2006, 2007-2012 and 2013 to 2018.

RESULTS

Comparison across the 3 time periods demonstrated significantly increasing frequency of older patients, asymptomatic CLP, male gender, smaller tumor size, elevated Ca 19-9, use of magnetic resonance imaging (MRI) and use of endoscopic ultrasound (EUS) prior to surgery. There was also significantly increasing frequency of adherence to the international guidelines as evidenced by the increasing proportion of HR^SG06 and HR^FG12 CLP with a corresponding lower proportion of LR^SG06 and LR^FG12 being resected. This resulted in a significantly higher proportion of resected CLP whereby the final pathology confirmed that a surgery was actually indicated.

CONCLUSIONS

Over time, there was increasing adherence to the international guidelines for the selection of patients for surgical resection as evidenced by the significantly increasing proportion of HR^SG06 and HR^FG06 CLPs undergoing surgery. This was associated with a significantly higher proportion of patients with a definitive indication for surgery. These suggested that over time, there was a continuous improvement in our selection of appropriate CLP for surgical treatment.

Successful Surgical Treatment of a Patient with Synchronic Intraductal Papillary Mucinous Carcinoma and Solid Pseudopapillary Neoplasm of the Pancreas

Intraductal papillary mucinous neoplasm (IPMN) and solid pseudopapillary neoplasm (SPN) are uncommon cystic tumors of the pancreas. The simultaneous occurrence of these 2 pancreatic neoplasms is extremely rare. We present a case of synchronous solid SPN and IPMN - carcinoma in a 44-year-old female patient. An uncommon surgical treatment was performed - pancreatoduodenectomy with the resection of the pancreas body, resection of the mesentericoportal trunk + distal pancreatectomy, and splenectomy. Part of the pancreatic tissue was preserved.

Hyalinized stroma is a characteristic feature of pancreatic intraductal oncocytic papillary neoplasm: An immunohistochemical study

Hyalinized stroma (HS) is a dense, eosinophilic, and amorphous extracellular material in the stroma. HS is observed in several tumors; however, it has not been comprehensively studied in pancreatic intraductal papillary mucinous neoplasm (IPMN) or intraductal oncocytic papillary neoplasm (IOPN). Here, we aimed to evaluate the immunohistochemical and microscopic characteristics of HS in IPMN and IOPN. The prevalence of HS was determined in 168 cases of IPMN, including intestinal type (IPMN-I), gastric type (IPMN-G), and pancreatobiliary type (IPMN-PB), as well as in 11 cases of IOPN. Immunohistochemical staining for laminin and collagen (types I, II, III, IV, and V), as well as Congo red staining were performed in IPMN and IOPN cases containing HS. The prevalence of HS among the IPMN and IOPN specimens was 1.2% (2/168 cases) and 45.5% (5/11 cases), respectively. The prevalence rates of HS in each IPMN subtype were as follows: 2.2% (2/91 cases) in IPMN-G, and 0% in IPMN-PB and IPMN-I. All seven HS cases were positive for collagen I, III, IV, and V but were negative for Congo red staining. Most cases showed negative, focal, or weak expression of laminin and type II collagen. These findings indicate that HS is associated with IOPN and is primarily composed of collagen fibers.

Outcomes of limited resection for patients with intraductal papillary mucinous neoplasm of the pancreas: A single-center experience

BACKGROUND

/ObjectivesThe aim of this study was to clarify the oncological outcomes of patients with intraductal papillary mucinous neoplasm (IPMN) who underwent limited resection (LR).

METHODS

This retrospective study analyzed the data of 110 patients with IPMN. Patients with IPMN without a history of pancreatitis who had neither tumor infiltration nor regional lymph node swelling on imaging findings underwent LR. We assessed the oncological outcomes of LR for patients with IPMN by comparing the surgical outcomes of LR and standard resection.

RESULTS

LR was performed in 50 patients (45.5%), including duodenum-preserving pancreatic head resection (n = 31), middle-pancreatectomy (n = 12), spleen-preserving distal pancreatectomy (n = 3), total parenchymal pancreatectomy (n = 3), and partial resection (n = 1). In the LR group, 18 patients had postoperative complications of Clavien-Dindo classification ≥ IIIa. After histopathological examination, the presence of high-grade dysplasia (HGD) and invasive carcinoma (IC) were observed in nine and three patients, respectively, in the LR group, and eight and 22 patients, respectively, in the standard resection group. There was a significant difference in the histopathological diagnosis of IC between the two groups (p < 0.001). Finally, in the LR group, postoperative recurrences occurred in three patients, and the 5-, 10-, and 15-year disease-specific survival rates were all 97.0%.

CONCLUSIONS

For patients with IPMN judged to have no infiltrating lesions based on the detailed imaging examination, LR is acceptable and may be considered as an alternative to standard resection.

Evidence of a common cell origin in a case of pancreatic mixed intraductal papillary mucinous neoplasm-neuroendocrine tumor

Recently, the term mixed neuroendocrine non-neuroendocrine neoplasms (MiNEN) has been proposed as an umbrella definition covering different possible combinations of mixed neuroendocrine-exocrine neoplasms. Among these, the adenoma plus neuroendocrine tumor (NET) combination is among the rarest and not formally recognized by the 2019 WHO Classification. In this setting, the debate between either collision tumors or true mixed neoplasms is still unsolved. In this report, a pancreatic intraductal papillary mucinous neoplasm (IPMN) plus a NET is described, and the molecular investigations showed the presence in both populations of the same KRAS, GNAS, and CDKN2A mutations and the amplification of the CCND1 gene. These data prove clonality and support a common origin of both components, therefore confirming the true mixed nature. For this reason, mixed neuroendocrine-exocrine neoplasms, in which the exocrine component is represented by a glandular precursor lesion (adenoma/IPMN) only, should be included into the MiNEN family.

Protruded duodenal tumor arising from Santorini's duct of the pancreas: a rare case of intraductal papillary mucinous neoplasm mimicking a duodenal polypoid tumor

Background

We experienced a rare case of intraductal papillary mucinous neoplasm arising from Santorini’s duct (SD) forming a tumor protruding into the duodenum .

Case presentation

A 71-year-old woman was incidentally diagnosed with a 3 cm type Isp polypoid tumor in the second portion of the duodenum at another hospital. Enhanced CT and endoscopic ultrasound revealed that the origin of this protruding tumor was arising from SD and that the tumor mimicked a pedunculated duodenal tumor. Our preoperative diagnosis was a malignant pancreatic tumor arising from SD with invasion into the duodenum. She underwent a subtotal stomach-preserving pancreaticoduodenectomy, and the resected specimen showed a 25 mm tumor protruding into the duodenum with a villous surface. The pathological findings revealed that the tumor was intraductal papillary mucinous adenoma (IPMA) arising from SD.

Conclusions

To the best of our knowledge, this is the first case of IPMA protruding into the duodenal lumen from SD, although most of the tumors arising from SD have been reported to be malignant.

Intraductal papillary mucinous neoplasm complicated with intraductal bleeding in a young woman mimicked a cystic solid pseudo-papillary tumor: a case report

BACKGROUND

There are only 6 cases of intraductal papillary mucinous neoplasm (IPMN) complicated with intraductal hemorrhage have been reported in English literatures. All these 6 cases of IPMN occurred in the old people. The present rare case of IPMN complicated with intraductal hemorrhage occurred in a young woman, and mimicked a cystic solid pseudo-papillary neoplasm (SPN) on preoperative imaging findings.

CASE PRESENTATION

A 29-year-old young woman complained of a sustained mild right upper quadrant abdominal pain. CT and MRI showed a lobulated, partly ill-defined cystic lesion located in the pancreatic head. Spotted calcification within cystic wall was seen on CT. The lesion was demonstrated as predominantly homogeneous hyperattenuation on CT and homogeneous high signal without decreased signal on fat suppression sequence on T1WI. After contrast administration, the cystic wall and septa of lesion was showed gradually mild to moderate degree of enhancement over time both on CT and MRI. No communication between lesion and the main duct was found on MRCP and the main pancreatic duct and common bile duct were not dilated. Considering patient's age, gender and manifestations of lesion on CT and MRI (calcification, bleeding and gradually enhanced pattern), the present case mimicked as a cystic SPN. The lesion was pathologically confirmed a branch type IPMN after surgical resection.

CONCLUSION

We propose that IPMN may need to be taken into account in the differential diagnosis when pancreatic cystic lesions occur in young women with bleeding, calcification, progressive enhancement of cystic wall and no communication with the main pancreatic duct.

Adenocarcinoma with intraductal papillary mucinous neoplasm arising in a duodenal heterotopic pancreas: a case report

A woman in her 70 s was diagnosed with a tumor in her duodenal wall during a routine visit for diabetes. She subsequently underwent subtotal stomach-preserving pancreatoduodenectomy. Histologically, the tumor was present mainly in the duodenal wall, and atypical cystic ducts were seen in the muscularis propria and subserosa. Invasive well-differentiated adenocarcinoma was seen in the duodenal submucosal and mucosal layers. Heterotopic pancreatic tissue was seen within the tumor, and atypical epithelium had proliferated and replaced the cystic ductal epithelium of the heterotopic pancreas. Therefore, adenocarcinoma with intraductal papillary mucinous neoplasm arising in duodenal heterotopic pancreas was the final histopathological diagnosis, which is considered rare.

A mixed-type intraductal papillary mucinous neoplasm of the pancreas with a histologic combination of gastric and pancreatobiliary subtypes in a 70-year-old woman: a case report

Background

Intraductal papillary mucinous neoplasms are rare papillary pancreatic neoplasms arising from major pancreatic ducts, characterized by duct dilation and mucin secretion. They comprise approximately 1% of all exocrine neoplasms and are classified according to their anatomical sites into main duct-type, branch duct-type, and mixed-type intraductal papillary mucinous neoplasms. Histological examination plays a crucial role in distinguishing and classifying intraductal papillary mucinous neoplasms into gastric, intestinal, pancreatobiliary, and oncocytic subtypes.

Case presentation

We present the case of a 70-year-old Syrian woman who was admitted to our hospital due to an intermittent epigastric pain accompanied by diarrhea and weight loss with a recent diagnosis of diabetes mellitus. Following clinical, laboratory, and radiological examination, distal pancreatectomy involving the body and the tail of the pancreas was performed. Interestingly, histological examination of the resected specimens revealed the diagnosis of a mixed-type intraductal papillary mucinous neoplasm with a unique combination of gastric and pancreatobiliary subtypes.

Conclusion

To the best of our knowledge, the combination of multiple histological subtypes of intraductal papillary mucinous neoplasms has been recorded in a few studies with reference to the challenging histological detection. Herein, we report a rare case with a significant histological combination, highlighting the difficulties in differential diagnosis due to the absence of ancillary techniques, with a brief review on diagnostic methods, histological characteristics and surgical recommendations.

Endoscopic Ultrasound-Guided Fine Needle Aspiration Cytologic Evaluation of Intraductal Papillary Mucinous Neoplasm and Mucinous Cystic Neoplasms of Pancreas

OBJECTIVES

To evaluate the role of endoscopic ultrasound-guided fine needle aspiration cytology in identifying mucinous cystic lesions (MCLs) in histologically proven cases of intraductal papillary mucinous neoplasm (IPMN) or mucinous cystic neoplasm (MCN) and risk of malignancy associated with each cytologic category based on the Papanicolaou Society of Cytopathology (PSC) guidelines.

METHODS

All resected cases with histologic diagnosis of IPMN or MCN at our institution from January 1, 2004, to August 31, 2019, with associated cytology were included. Available cytology slides of nondiagnostic (ND), negative/benign (BN), and atypical cytology (AC) cases were reviewed and reclassified based on the PSC guidelines.

RESULTS

A total of 120 cases were identified, including 57 IPMNs with low-grade or moderate dysplasia (LGD/MD) and high-grade dysplasia (HGD), 34 MCNs with LGD/MD or HGD, and 29 IPMNs with invasive malignancy. After cytology slide review and reclassification, we observed that ND and BN cases were paucicellular and lacked ancillary testing (carcinoembryonic antigen levels or KRAS mutation analysis). The risk-of-malignancy rates were 33% for ND, 11% for BN, 28.5% for AC, 17% for MCL, and 100% for suspicious/positive cytologic diagnosis.

CONCLUSIONS

A multidisciplinary approach including combined use of cytology and ancillary testing is helpful in establishing a diagnosis of MCL and identifying associated malignancy.

Differential diagnosis of pancreatic cysts: A prospective study on the role of intra-cystic glucose concentration

BACKGROUND

The accuracy and costs of current diagnostic methods in the differential diagnosis of pancreatic cystic lesions still has ample room for improvement.

AIMS

The aim of the study was to confirm the diagnostic yield of intracystic glucose in the diagnosis of pancreatic cyst subtypes.

METHODS

We prospectively recruited all patients who underwent Endoscopic Ultrasound with Fine Needle Aspiration of pancreatic cyst at our Institution.

RESULTS

Fifty-six patients were included in the study. We found that intracystic glucose concentration < 50 mg/dL was significantly more sensitive than a concentration of Carcinoembryonic Antigen > 192 ng/mL (93.6% vs 54.8%; p = 0.003) for the diagnosis of mucinous cysts. In terms of specificity, the two markers were not different (96% vs 100%; p = 1). Regarding the diagnosis of non-mucinous cysts, intracystic glucose concentration ≥ 50 mg/mL showed higher sensitivity than Carcinoembryonic Antigen level < 5 ng/mL (96% vs 72%) although a statistical significance could not be reached (p = 0.07). The two markers were not statistically different in terms of specificity (93.6% vs 87.1%; p = 0.62).

CONCLUSION

Given its diagnostic performance and ease of measurement, intracystic glucose may replace Carcinoembryonic Antigen in the differential diagnosis of mucinous versus non-mucinous pancreatic cysts.

Pearls and pitfalls of imaging features of pancreatic cystic lesions: a case-based approach with imaging-pathologic correlation

A variety of neoplastic and non-neoplastic lesions of the pancreas can present with a predominantly cystic architecture. These lesions are increasingly being detected as incidental findings on routine cross-sectional imaging following technological advances in these techniques and their widespread use. The different histopathological behaviors show various common and uncommon imaging findings, and some cases show similar appearance in spite of different histopathology. Each lesion requires specific management because of the differing risk of progression to malignancy, and an accurate imaging diagnosis is crucial. The typical imaging characteristics that differentiate pancreatic cystic lesions have been well described and fully summarized. However, in addition to a small percentage of cases that shows uncommon imaging findings, a substantial percentage of cystic lesions shows overlapping imaging findings that can lead to radiological misdiagnosis. For appropriate diagnosis and optimal treatment strategy, it is important to know the uncommon and overlapping imaging findings of these lesions, in addition to familiarity with the typical aspects. In this article, we reconfirm the well-known characteristic imaging features of pancreatic cystic lesions and present several diagnostically challenging cases, focusing on the uncommon and overlapping imaging findings.

A case report of pancreatic panniculitis due to acute pancreatitis with intraductal papillary mucinous neoplasm

BACKGROUND

Pancreatic panniculitis is a rare skin manifestation in pancreatic disease patients that most frequently develops on the lower legs. We report the unique case of a 68-year-old man who suffered from pancreatic panniculitis on his trunk associated with acute pancreatitis due to an intraductal papillary mucinous neoplasm.

CASE PRESENTATION

A 68-year-old man complained of a 2-day history of a tender subcutaneous nodule on his trunk. Laboratory tests and abdominal contrast computed tomography were consistent with acute pancreatitis due to an intraductal papillary mucinous neoplasm. A skin biopsy of the nodule histologically displayed lobular panniculitis with characteristic "ghost cells", which indicated pancreatic panniculitis.

CONCLUSIONS

In order to avoid a missed or delayed diagnosis, clinicians should bear in mind that pancreatic panniculitis can be the first manifestation of pancreatic disease when encountering subcutaneous nodules on the trunk.

Validation of the clinical utility of 4 guidelines in the initial triage of mucinous cystic lesions of the pancreas based on cross-sectional imaging: Experience with 188 surgically-treated patients

INTRODUCTION

Over the years, several guidelines have been introduced to guide management of mucinous pancreatic cystic neoplasms (mPCN). In this study, we aimed to evaluate and compare the clinically utility of the Sendai-06, Fukuoka-12, Fukuoka-17 and European-18 guidelines in predicting malignancy of mPCN.

METHODS

One hundred and eighty-eight patients with mucinous cystic neoplasms (MCN) or intraductal papillary mucinous neoplasm (IPMN) who underwent surgery were retrospectively reviewed and classified under the 4 guidelines. Malignancy was defined as high grade dysplasia and invasive carcinoma.

RESULTS

Raised CA19-9>37U/ml, enhancing mural nodule≥5 mm and main pancreatic duct≥10 mm were significantly associated with malignancy on multivariate analysis. Increasing number of high risk features, absolute indications (European-18), worrisome risk or relative indications (European-18) were significantly associated with an increased likelihood of malignancy. The positive predictive values (PPV) of high risk features for Sendai-06, Fukuoka-12, Fukuoka-17 and absolute indications (European-18) for malignancy were 53%, 76%, 78% and 78% respectively. The negative predictive values (NPV) of the Sendai-06, Fukuoka-12 and Fukuoka-17 were 100%, while that of the European-18 was 92%. Risk of malignancy for patients with ≥4 worrisome features (Fukuoka-17) and ≥3 relative indications (European-18) was 66.7% and 75.0% respectively.

CONCLUSIONS

All 4 guidelines studied were useful in the initial triage of mPCN for the risk stratification of malignancy. The Fukuoka-17 had the highest PPV and NPV.

Independent predictors of secondary invasive pancreatic remnant tumors after initial resection of an intraductal papillary mucinous neoplasm: a nationwide large-scale survey in Japan

PURPOSE

There is no standardized surveillance protocol after intraductal papillary mucinous neoplasm (IPMN) resection. We report the findings of a large-scale survey in Japan, investigating the independent predictors of secondary invasive tumors by analyzing the epidemiology of secondary tumors of the remnant pancreas after initial IPMN resection.

METHODS

An institutional questionnaire about the remnant pancreas after pancreas resection was distributed at the 41st Annual Meeting of the Japanese Society of Pancreatic Surgery in Tokyo. We retrospectively analyzed the patient data including pathological diagnosis, postoperative outcomes, and evaluation methods.

RESULTS

Redo pancreatectomy was performed for secondary disease in 213 (1.4%) of a total 15,777 patients. Eighty-eight of these 213 patients had undergone initial resection of IPMN. The types of secondary tumors after IPMN resection significantly depended on those of the primary tumors. Through short-interval and long-term follow-up, most of the secondary tumors were detected within 1-4 years. Logistic regression analysis revealed that the initial pathological diagnosis of invasive IPMN was an independent predictor of secondary invasive tumors in the remnant pancreas.

CONCLUSION

Primary invasive IPMN proved to be a significant predictor of secondary invasive IPMN. Both short-interval and long-term follow-up may help to determine the prognosis of patients after IPMN resection.

Importance of each high-risk stigmata and worrisome features as a predictor of high-grade dysplasia in intraductal papillary mucinous neoplasms of the pancreas

BACKGROUND

High-risk stigmata (HRS) and 'worrisome features' (WFs) are defined as predictive factors for malignancies of intraductal papillary mucinous neoplasms (IPMNs). We performed this study to determine the importance and odds ratio (OR) of each HRS and WFs as predictors for high-grade dysplasia (HGD).

METHODS

We analyzed 295 patients who underwent pancreatectomy for branch duct and mixed-type IPMN, and evaluated the association between HRS and WFs (as defined by the '2017 Fukuoka Consensus Guidelines') and HGD.

RESULTS

The proportions of patients with low-grade dysplasia (LGD), HGD, and invasive carcinoma were 47%, 28%, and 25%, respectively. Multivariate analysis comparing patients with LGD and HGD using all HRS and WFs revealed that an enhancing mural nodule ≥5 mm (OR: 4.1), pancreatitis (OR: 2.2), and thickened/enhancing cyst walls (OR: 2.2) were independent predictive factors for HGD. Based on the OR (the former factor is two points and the latter two factors are each one point), the incidence of HGD in patients with none (n = 43), one (n = 82), two (n = 25), three (n = 52), and four (n = 19) of these predictive factors were 9%, 26%, 52%, 62%, and 63%, respectively. Assuming a score of one or higher as a surgical indication, the sensitivity, specificity, positive predict value, and negative predict value of HGD were 95, 38, 44, and 91%.

CONCLUSIONS

Our derived scoring system using more important factors in HRS and WFs may be useful for predicting HGD and determining surgical indications 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, via χ² (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.

Rare coincidence of intraductal papillary mucinous neoplasm and type 1 autoimmune pancreatitis

The present case involved a 60-year-old man with autoimmune pancreatitis (AIP). While his AIP was in remission for 6 years, a follow-up CE-CT revealed a dilated main pancreatic duct (MPD) and an enhanced mural nodule. Fluorodeoxyglucose uptake was positive on positron emission tomography. Endoscopic retrograde pancreatography showed a filling defect of the MPD, and pancreatoscopy revealed a nodule partially covered with papillary lesions. Although a repeat biopsy revealed no evidence of malignancy, we speculated that there was a high likelihood of main-duct-type intraductal papillary mucinous neoplasm (IPMN)-derived carcinoma concomitant with AIP. Subsequently, the patient underwent subtotal stomach-preserving pancreaticoduodenectomy. A surgical specimen showed a 35 mm protuberant papillary lesion with abundant stroma, located in the main duct of the pancreas. Further histological evaluation revealed that the nodule was predominantly composed of IPMN with low-grade dysplasia, which was accompanied by abundant IgG4-positive lymphoplasmacytic infiltration, and fibrosis existed predominantly around the IPMN. The epithelium of the cyst showed mucinous hyperplasia with focal papillary structures of gastric phenotype (MUC5A+, MUC6+, MUC1-, MUC2-, CDX-). After surgical resection, we did not find any imaging evidence suggesting a recurrent tumor and AIP relapse in the remnant pancreas. In conclusion, we report a case of IPMN coincidentally found in a patient with type 1 AIP. Active AIP may exaggerate the morphology of IPMN, and careful evaluation should be performed to select appropriate management.

Management of Pancreatic Cystic Lesions

BACKGROUND

The prevalence of undefined pancreatic cystic neoplasms (PCNs) is high in the general population, increasing with patient age. PCNs account for different biological entities with different potential for malignant transformation. The clinician must balance his or her practice between the risk of surgical overtreatment and the error of keeping a malignant lesion under surveillance.

METHODS

We review and discuss the clinical management of PCNs. Specifically, we analyze the main features of PCNs from the surgeon's point of view, as they present in the outpatient clinic. We also review the different consensus guidelines, address recent controversies in the literature, and present the current clinical practice at 4 different European Centers for pancreatic surgery.

RESULTS

The main features of PCNs were analyzed from the surgeon's point of view as they present in the outpatient clinic. All aspects of surgical management were discussed, from indications for surgery to intraoperative management and surveillance strategies.

CONCLUSIONS

Management of PCNs requires a selective approach with the aim of minimizing clinically relevant diagnostic mistakes. Through the evaluation of clinical and radiological features of a PCN, the surgeon can elaborate on a diagnostic hypothesis and assess malignancy risk, but the final decision should be tailored to the individual patient's need.

An elevated CA 19-9 is associated with invasive cancer and worse survival in IPMN

BACKGROUND

Current guidelines for IPMN include an elevated serum carbohydrate antigen (CA) 19-9 among the worrisome features. However, the correlation of CA 19-9 with histological malignant features and survival is unclear. Serum CEA is also currently used for preoperative management of IPMN, although its measurement is not evidence-based. Accordingly, we aimed to assess the role of these tumor markers as predictors of malignancy in IPMN.

METHODS

IPMN resected between 1998 and 2018 at Massachusetts General Hospital were analyzed. Clinical, pathological and survival data were collected and compared to preoperative levels of CA 19-9 and CEA. Receiver operating characteristic (ROC) and Cox regression analyses were performed considering cut-offs of 37 U/ml (CA 19-9) and 5 μg/l (CEA).

RESULTS

Analysis of 594 patients showed that preoperative CA 19-9 levels > 37 U/ml (n = 128) were associated with an increased likelihood of invasive carcinoma when compared to normal levels (45.3% vs. 18.0%, P < 0.001), while there was no difference with respect to high-grade dysplasia (32.9% vs 31.9%, P = 0.88). The proportion of concurrent pancreatic cancer was higher in patients with CA 19-9 > 37 U/ml (17.2% vs 4.9%, P < 0.001). An elevated CA 19-9 was also associated with worse overall and disease-free survival (HR = 1.943, P = 0.007 and HR = 2.484, P < 0.001 respectively). CEA levels did not correlate with malignancy.

CONCLUSION

In patients with IPMN, serum CA19-9 > 37 U/ml is associated with invasive IPMN and concurrent pancreatic cancer as well as worse survival, but not with high-grade dysplasia. Serum CEA appears to have minimal utility in the management of these patients.

Simple mucinous cysts of the pancreas have heterogeneous somatic mutations

Simple mucinous cysts of the pancreas have an epithelial lining resembling pancreatic intraepithelial neoplasia but may have a clinical presentation similar to premalignant mucinous neoplasms such as intraductal papillary mucinous neoplasms. Whether the epithelial lining shares genomic alterations with other pancreatic preinvasive neoplasms such as PanIN and intraductal papillary mucinous neoplasm has not been determined. We performed targeted sequencing analysis using a custom-designed MiSeq panel including the full coding regions of 18 pancreatic cancer genes on 13 clinically and pathologically well-characterized simple mucinous cysts. We detected 59 mutations in 15 genes in the cohort, with a median of 4 mutations per cyst (range = 0-16 mutations per cyst). The mutated genes and rate of detected mutations were as follows: KMT2C (MLL3) (62%), KRAS (15%), BRAF (8%), RNF43 (8%), CDKN2a (8%), TP53 (15%), and SMAD4 (8%). No GNAS mutations were detected. Four cases (31%) had no mutations detected. These findings place the majority of simple mucinous cysts of the pancreas in the spectrum of early, low-grade mucinous neoplasia, albeit with a different spectrum of genomic alterations compared with PanIN and intraductal papillary mucinous neoplasm.

Molecular Diagnosis of Cystic Neoplasms of the Pancreas: a Review

BACKGROUND

The prevalence of incidental pancreatic cystic neoplasms (PCNs) has increased dramatically with advancements in cross-sectional imaging. Diagnostic imaging is limited in differentiating between benign and malignant PCNs. The aim of this review is to provide an overview of biomarkers that can be used to distinguish PCNs.

METHODS

A review of the literature on molecular diagnosis of cystic neoplasms of the pancreas was performed.

RESULTS

Pancreatic cysts can be categorized into inflammatory and non-inflammatory lesions. Inflammatory cysts include pancreatic pseudocysts. Noninflammatory lesions include both mucinous and non-mucinous lesions. Mucinous lesions include intraductal papillary mucinous neoplasm (IPMN) and mucinous cystic neoplasm. Non-mucinous lesions include serous cystadenoma and solid-pseudopapillary tumor of the pancreas. Imaging, cyst aspiration, and histologic findings, as well as carcinoembryonic antigen and amylase are commonly used to distinguish between cyst types. However, molecular techniques to detect differences in genetic mutations, protein expression, glycoproteomics, and metabolomic profiling are important developments in distinguishing between cyst types.

DISCUSSION

Nomograms incorporating common clinical, laboratory, and imaging findings have been developed in a better effort to predict malignant IPMN. The incorporation of top molecular biomarker candidates to nomograms may improve the predictive ability of current models to more accurately diagnose malignant PCNs.

ACR Appropriateness Criteria® Pancreatic Cyst

Incidental pancreatic cysts are increasingly detected on imaging studies performed for unrelated indications and may be incompletely characterized on these studies. Adequate morphological characterization is critical due to the small risk of malignant degeneration associated with neoplastic pancreatic cysts, as well as the risk of associated pancreatic adenocarcinoma. For all pancreatic cysts, both size and morphology determine management. Specifically, imaging detection of features, such as pancreatic ductal communication and presence or absence of worrisome features or high-risk stigmata, have important management implications. The recommendations in this publication determine the appropriate initial imaging study to further evaluate a pancreatic cyst that was incidentally detected on a nondedicated imaging study. The recommendations are designed to maximize the yield of diagnostic information in order to better risk-stratify pancreatic cysts and assist in guiding future management. The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision include an extensive analysis of current medical literature from peer reviewed journals and the application of well-established methodologies (RAND/UCLA Appropriateness Method and Grading of Recommendations Assessment, Development, and Evaluation or GRADE) to rate the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where evidence is lacking or equivocal, expert opinion may supplement the available evidence to recommend imaging or treatment.