Diagnostic significance of a dilated orifice of the duodenal papilla in intraductal papillary mucinous neoplasm of the pancreas

Diagnosis and Management of Pancreatic Cysts

As pancreatic cyst incidence rises, likely due to the ubiquitous increase in cross-sectional imaging, their management presents multiple challenges for both the practitioner and patient. It is critical that all pancreatic cysts are appropriately characterized, as treatment decisions depend on an accurate diagnosis. Diagnostic modalities such as cytology, biopsy, and cyst fluid biomarkers allow for definitive diagnosis of virtually all lesions. Some cysts, such as intraductal papillary mucinous neoplasms, mucinous cystic neoplasms, and cystic pancreatic endocrine neoplasms, have malignant potential and must be surveyed. Other cysts, such as serous cystadenomas and pancreatic fluid collections, do not have malignant potential. Surveillance strategies vary widely depending on cyst type and size and while multiple medical societies advocate surveillance, their published surveillance guidelines are heterogenous. Cysts with high-risk stigmata or worrisome features are usually resected, depending on the patient's surgical fitness. In patients unfit for resection, newer endoscopic ablative techniques are advocated. Controversial aspects regarding cyst management include whether surveillance can be stopped, how surveillance should be performed, and the extensive financial burden cyst management places on the health care system. Further study into the natural history of cystic lesions, including definitive determination of the rate of malignant transformation for each cyst type, is essential.

Resection of pancreatic cystic neoplasms in recurrent acute pancreatitis prevents recurrent pancreatitis but does not identify more malignancies

BACKGROUND

Recurrent acute pancreatitis (RAP) may be a presenting feature of and an indication for resection of pancreatic cysts, including intra-ductal papillary mucinous neoplasm (IPMN). Few data are available regarding the prevalence of malignancy and post-operative RAP in this population.

AIM

To study the role of resection to help prevent RAP and analyze if presentation as RAP would be a predictor for malignancy.

METHODS

This retrospective study assessed 172 patients who underwent surgical resection of pancreatic cystic neoplasms at a university hospital between 2002 and 2016. The prevalence of preoperative high-risk cyst features, and of neoplasia was compared between patients with and without RAP. To identify the cause of pancreatitis, all the patients had a detailed history of alcohol, smoking, medications obtained, and had cross-sectional imaging (contrast-enhanced computed tomography/magnetic resonance imaging) and endoscopic ultrasound to look for gallstone etiology and other structural causes for pancreatitis. The incidence of RAP post-resection was the primary outcome.

RESULTS

IPMN accounted for 101 cases (58.7%) {[branch duct (BD) 59 (34.3%), main duct (MD) 42] (24.4%)}. Twenty-nine (16.9%) presented with RAP (mean 2.2 episodes): 15 had BD-IPMN, 8 MD-IPMN, 5 mucinous cystic neoplasm and 1 serous cystic neoplasm. Malignancy was similar among those with vs without RAP for all patients [6/29 (20.7%) vs 24/143 (16.8%)] and IPMN patients [6/23 (26.1%) vs 23/78 (29.5%)], although tended to be higher with RAP in BD-IPMN, [5/15 (33.3%) vs 3/44 (6.8%), P = 0.04]. At mean follow-up of 7.2 years, 1 (3.4%) RAP patient had post-resection RAP. The mean episodes of acute pancreatitis before vs after surgery were 3.4 vs 0.02 (P < 0.0001).

CONCLUSION

Malignancy was not increased in patients with pancreatic cystic neoplasms who have RAP compared to those without RAP. In addition, specific cyst charac-teristics were not clearly associated with RAP. The incidence of RAP was markedly decreased in almost all patients following cyst resection.

The CT fish mouth ampulla sign: a highly specific finding in main duct and mixed intraductal papillary mucinous neoplasms

OBJECTIVE

Main duct and mixed intraductal papillary mucinous neoplasms (IPMN) are pre-malignant cystic pancreatic neoplasms associated with pancreatic duct dilatation. Distinguishing these from benign causes of pancreatic duct dilatation is important in order to allow appropriate surveillance or surgery. A patulous duodenal papilla with extrusion of mucus at endoscopic evaluation, the endoscopic fish mouth ampulla (E-FMA) sign, is reported in main duct and mixed IPMN. We aimed to establish whether a CT correlate (CT-FMA) of this sign exists and whether this was associated with the presence of invasion or high-grade dysplasia. We defined the CT-FMA sign as an uninterrupted column of water attenuation material running from the pancreatic duct to the duodenal lumen.

METHODS

A retrospective, blinded review of 44 patients with histologically confirmed IPMN and 87 age-matched controls with pancreatic duct dilatation on CT was undertaken. A case-control series matched for the degree of pancreatic duct dilatation was used to compare the rates of invasion or high-grade dysplasia between main duct and mixed IPMN patients, with and without a CT-FMA sign.

RESULTS

The CT-FMA sign could be identified in 18.5% patients with main duct/mixed IPMN with specificity 100%, positive predictive value 100% and negative predictive value 79.8%. A significant association was found between CT-FMA in main duct/mixed IPMN compared to controls, but not with the presence of high-grade dysplasia or invasion.

CONCLUSIONS

The CT-FMA sign is a newly reported, highly specific sign of MD and mixed IPMN.

ADVANCES IN KNOWLEDGE

If a fish mouth ampulla is identified at CT, a diagnosis of main duct or mixed IPMN is highly likely.

Clinical assessment of the GNAS mutation status in patients with intraductal papillary mucinous neoplasm of the pancreas

Intraductal papillary mucinous neoplasm (IPMN) of the pancreas is characterized by cystic dilation of the pancreatic duct, caused by mucin hypersecretion, with slow progression via the adenoma-carcinoma sequence mechanism. Mutation of GNAS at codon 201 is found exclusively in IPMNs, occurring at a rate of 41-75%. Recent advances in molecular biological techniques have demonstrated that GNAS mutation might play a role in the transformation of IPMNs after the appearance of neoplastic cells, rather than in the tumorigenesis of IPMNs. GNAS mutation is observed frequently in the intestinal subtype of IPMNs with MUC2 expression, and less frequently in IPMNs with concomitant pancreatic ductal adenocarcinoma (PDAC). Research has focused on assessing GNAS mutation status in clinical practice using various samples. In this review, we discuss the clinical application of GNAS mutation assessment to differentiate invasive IPMNs from concomitant PDAC, examine the clonality of recurrent IPMNs in the remnant pancreas using resected specimens, and differentiate pancreatic cystic lesions using cystic fluid collected by endoscopic ultrasound-guided fine needle aspiration (EUS-FNA), duodenal fluid, and serum liquid biopsy samples.

Impact of magnetic steering on gastric transit time of a capsule endoscopy (with video)

BACKGROUNDS AND AIMS

Delayed gastric transit of the capsule may lead to incomplete small bowel examination, reducing the diagnostic yield. Thus, this study was designed to determine if magnetic steering could enhance capsule gastric emptying and mucosal visualization within the duodenum.

METHODS

The intervention group comprised 100 patients undergoing magnetic-controlled capsule endoscopy between May to September 2017 in whom magnetic control was used to assist transpyloric passage of the capsule and duodenal inspection. A cohort of 100 patients who had undergone the procedure before May 2017 was randomly selected from the database as an historic control group in whom transpyloric movement of the capsule occurred spontaneously (without magnetic assistance). The difference in the pyloric transit time (PTT) and duodenal papilla detection rate (DPDR) between the 2 groups were compared, and related factors were also investigated.

RESULTS

Transpyloric passage of the capsule under magnetic control was successfully performed in 59 patients (59%). Median PTT was greatly reduced in the intervention group from 58.38 minutes (range, 13.45-87.47) to 4.69 minutes (range, 1.56-55.00; P < .001), and DPDR was also greatly improved with magnetic steering (30.5% vs 9%, P < .001). Magnetic steering, male gender, and higher body mass index were independently associated with reduced gastric transit time and magnetic steering with an enhanced DPDR.

CONCLUSIONS

Magnetic steering of the capsule can enhance gastric emptying of the capsule and may prove useful in nonobese and female patients who appeared to have longer gastric transit time and achieved a better DPDR than that under the action of peristalsis alone. (Clinical trial registration number: NCT03441945.).

Management of Incidental Pancreatic Cystic Lesions

BACKGROUND

Pancreatic cystic lesions (PCL) are common. They are increasingly detected as an incidental finding of transabdominal ultrasound or cross-sectional imaging. In contrast to other parenchymal organs, dysontogenetic pancreatic cysts are extremely rare. In symptomatic patients the most frequent PCL are acute and chronic pseudocysts. The majority of incidental cystic lesions, however, are neoplasias which have different risks of malignancy.

METHODS

PubMed was searched for studies, reviews, meta-analyses, and guidelines using the following key words: ('pancreatic cystic lesions' OR 'cystic pancreatic lesions' OR 'intraductal papillary mucinous neoplasia' OR 'mucinous cystic neoplasia' OR 'pancreatic cyst' OR 'pancreatic pseudocyst') AND (management OR treatment OR outcome OR prognosis OR diagnosis OR imaging OR 'endoscopic ultrasound' EUS-FNA OR EUS OR 'endoscopic ultrasonography' OR CT OR MRI). Retrieved papers were reviewed with regard to the diagnostic and therapeutic management of incidental PCL.

RESULTS

In addition to clinical criteria, transabdominal ultrasonography including contrast-enhanced ultrasonography, cross-sectional radiological imaging, and endoscopic ultrasound (EUS) are used for diagnostic characterization and risk assessment. EUS plays an outstanding role in differential diagnosis and prognostic characterization of incidental PCL. In a single examination it is possible to perform high-resolution morphological description, perfusion imaging, as well as fine-needle aspiration of cyst content, cyst wall, and solid components. An international consensus guideline has defined worrisome and high-risk criteria for the risk assessment of mucinous pancreatic cysts, which are mainly based on the results of EUS and cross-sectional imaging. Nevertheless, despite diagnostic progress and guideline recommendations, differential diagnosis and management decisions remain difficult. This review will discuss problems in and approaches to the diagnosis of incidental PCL.

CONCLUSION

An evidence-based algorithm for the diagnosis of incidental PCL is proposed.

Acute pancreatitis in intraductal papillary mucinous neoplasms: A common predictor of malignant intestinal subtype

BACKGROUND

Acute pancreatitis (AP) is a common presenting symptom of intraductal papillary mucinous neoplasms (IPMN). Our objective was to evaluate the clinical and pathologic features of IPMN that present with AP. We hypothesized that the intestinal epithelial subtype, which produces a highly viscous mucin containing MUC2 glycoprotein, is associated with the development of AP.

METHODS

We performed a case-control study, evaluating 325 patients with IPMN resected at our institution. Clinicopathologic features were assessed for patients with and without a history of AP and compared between the 2 groups.

RESULTS

A history of AP was found in 69 patients (21%). Of those, 33 (48%) experienced a single episode, and some patients had as many as 10 distinct attacks. Three patients presented with necrotizing pancreatitis requiring operative debridement. After resection, recurrent AP occurred in only 14%. A history of AP was associated with younger age (61 vs 70, P < .001), main duct involvement (odds ratio [OR] 1.73, 95% confidence interval [95% CI] 1.00-3.01; P = .049), intestinal subtype (OR 4.84, 95% CI 2.71-8.67; P < .001), and high-grade dysplasia (OR 1.82, 95% CI 1.07-3.11; P = .028). On multivariate analysis, AP was an independent predictor of intestinal subtype (OR 4.69, 95% CI 2.48-8.84, P < .001), malignancy (OR 1.97, 95% CI 1.07-3.63, P = .029), and main duct involvement (OR 1.87, 95% CI 1.02-3.43, P = .044).

CONCLUSION

AP is a frequent presenting symptom of IPMN. These patients are younger and have greater odds of harboring malignant intestinal-type IPMN involving the main pancreatic duct.

"High-risk stigmata" of the 2012 international consensus guidelines correlate with the malignant grade of branch duct intraductal papillary mucinous neoplasms of the pancreas

OBJECTIVES

The 2012 international consensus guidelines for the management of intraductal papillary mucinous neoplasm (IPMN) of the pancreas stratified patients into 2 clinical categories, "high-risk stigmata" and "worrisome features," and recommended different therapeutic strategies for these groups. The aim of this study was to elucidate the significance of these categories in terms of predicting malignant IPMNs.

METHODS

The medical records of 100 consecutive patients who underwent pancreatectomy for IPMNs were retrospectively reviewed. Seventy patients with branch duct IPMNs (BD-IPMNs) were stratified into 3 groups. The relationships between the number of predictive factors and histopathologic grade were investigated.

RESULTS

The prevalence rates of malignant IPMN, invasive carcinoma, and lymph node metastasis in the high-risk group were 80%, 55%, and 20%, respectively, with these percentages significantly increasing in a stepwise manner according to the number of predictive factors. In contrast, there was no significant correlation between the number of worrisome features and grade of malignancy in patients stratified as having worrisome BD-IPMNs.

CONCLUSIONS

The number of high-risk stigmata correlated significantly with the grade of malignancy of BD-IPMNs. The presence of at least 1 high-risk stigma in patients with BD-IPMNs indicates a need for pancreatectomy with lymphadenectomy.

Prediction of malignancy with endoscopic ultrasonography in patients with branch duct-type intraductal papillary mucinous neoplasm

OBJECTIVE

We evaluated the accuracy of a new endoscopic ultrasonography (EUS) scoring system to predict malignancy in branch duct-type intraductal papillary mucinous neoplasms (BD-IPMNs).

METHODS

We performed a retrospective multicenter study of patients who underwent EUS within 3 months before surgery and were diagnosed as having BD-IPMNs by postoperative pathologies at 8 hospitals in Korea from August 2002 to December 2011. To predict the malignancy, we applied the EUS scoring system consisting of pancreatic cyst size, height of mural nodules, main duct dilatation, septal thickening, and patulous orifice. We evaluated the diagnostic accuracy of the new EUS scoring system and compared it with previous individual risk factors.

RESULTS

Eighty-four patients (male-to-female ratio, 55:29; mean [SD] age, 64.7 [7.1] years) had 68 benign BD-IPMNs and 16 malignant intraductal papillary mucinous neoplasms. The EUS scoring system showed 75.0% sensitivity and 94.1% specificity at 7 points. This system (area under the curve, 0.939; 95% confidence interval, 0.884-0.994) resulted in a more accurate prediction than the previous known other factors including Sendai criteria, dilatation of ducts, size of the cyst, and presence of septal thickening and mural nodules.

CONCLUSIONS

The EUS scoring system predicted BD-IPMN malignancy more accurately than the Sendai criteria and individual risk factors.

Elevated expression level of microRNA-196a is predictive of intestinal-type intraductal papillary mucinous neoplasm of the pancreas

OBJECTIVES

Aberrant expression of several microRNAs (miRs) has been reported in various neoplasms including intraductal papillary mucinous neoplasms (IPMNs) of the pancreas. MicroRNA-196a (miR-196a) is up-regulated in Barrett esophagus (characterized by intestinal metaplasia) and in colorectal cancer; this relationship between intestinal characteristics and miR-196a might also be applicable to intestinal-type IPMNs. The aim of this study was to evaluate whether intestinal-type IPMNs can be discriminated from non-intestinal-type IPMNs by the expression level of miR-196a in tissue and pancreatic juice samples.

METHODS

Thirty-seven formalin-fixed paraffin-embedded tissue samples (including 3 of normal pancreatic ducts) and 36 pancreatic juice samples were obtained. The expression level of miR-196a measured by quantitative reverse transcription-polymerase chain reaction assays was compared between intestinal-type and non-intestinal-type IPMNs.

RESULTS

MicroRNA-196a expression in intestinal-type IPMN tissue samples (n = 18) was significantly higher than that of non-intestinal-type IPMNs (n = 16) (P < 0.001). Similarly, miR-196a expression in pancreatic juice samples of intestinal-type IPMNs (n = 6) was significantly higher than that of non-intestinal-type IPMNs (n = 30) (P = 0.008), and the sensitivity and specificity for prediction of intestinal-type IPMNs using pancreatic juice samples were both 83%.

CONCLUSIONS

Elevated expression of miR-196a in pancreatic juice samples is predictive of intestinal-type IPMNs.

Dilated papilla with mucin extrusion is a potential predictor of acute pancreatitis associated with intraductal papillary mucinous neoplasms of pancreas

BACKGROUND/OBJECTIVES

As intraductal papillary mucinous neoplasm (IPMN) of the pancreas is associated with acute pancreatitis (AP) in some cases, predicting the risk of pancreatitis is as important as predicting the risk of malignancy in IPMN cases. In this study, we attempted to clarify the characteristics of IPMN associated with AP, compared to those of IPMN not associated with AP.

METHODS

From January 2006 to March 2013, data from 88 patients who underwent surgery for IPMN were retrospectively investigated and analyzed. We evaluated clinical and pathological variables of each patient and compared patients with IPMN with AP to those without AP. Furthermore, we presented representative cases of mild and severe pancreatitis caused by IPMN.

RESULTS

Overall, 12 of 88 patients with IPMN (13.6%) had AP. Seven of the 12 patients had a single episode of AP, whereas the remaining 5 patients were diagnosed with IPMN with repeated AP. Ten of 12 patients with AP were diagnosed with mild AP and the remaining 2 with severe AP. Regarding clinical findings, the proportion of dilated papilla with mucin extrusion was significantly higher in patients with IPMN with AP than in those without AP (p = 0.035). Histological findings indicated that the proportion of intestinal-subtype IPMN was significantly higher in patients with IPMN with AP (p = 0.013).

CONCLUSIONS

AP caused by IPMN derives mostly from intestinal IPMN. Dilated papilla with mucin extrusion can be a potential predictor of AP.

First clinical trial of a newly developed capsule endoscope with panoramic side view for small bowel: a pilot study

BACKGROUND AND STUDY AIMS

Capsule endoscopy is the first-line diagnostic technique for the small bowel. However, the inability to visualize the duodenal papilla is an inherent limitation of this method. In the present study, we evaluated feasibility of a newly developed CapsoCam SV1 capsule.

PATIENTS AND METHODS

This is a prospective dual center study of a newly developed video capsule CapsoCam SV1 from Capsovision, CA, providing panoramic 360° imaging. A high frequency of 20 frames occurs per second for the first 2 h and thereafter 12 frames/s, with a battery life of 15 h. We evaluated feasibility and completeness of small bowel examination together with secondary endpoints of duodenal papilla detection in 33 patients. Patients swallowed the capsules following colonoscopy or were prepared with 2 L of polyethylene glycol solution prior to the examination. All patients swallowed 20 mg of metoclopramide and 160 mg of simethicone 30 min before ingestion of the capsule.

RESULTS

Thirty-one of the 33 patients' data could be evaluated. Small bowel examination was complete in all procedures. Mean time to pass the small bowel was 258 ± 136 min. Average small bowel cleanliness was 3.3 ± 0.5. In 71% of the patients, we identified the duodenal papilla. No adverse reaction in relation to the capsule examination was observed.

CONCLUSIONS

CapsoCam SV1 is a safe and efficient tool in small bowel examination. The duodenal papilla as the only landmark in small bowel is detected in more than 70% of the patients.