High expression of intestinal-type mucin (MUC2) in intraductal papillary mucinous neoplasms coexisting with extrapancreatic gastrointestinal cancers

Esophagogastroduodenal Findings in Patients with Intraductal Papillary Mucinous Neoplasms

The association between intraductal papillary mucinous neoplasms (IPMNs) and extra-pancreatic malignancies is controversial. This cross-sectional study compared esophagogastroduodenal findings in 340 IPMN patients to those of age- and gender-matched controls without known IPMNs who underwent esophagogastroduodenoscopies (EGDs) for similar clinical reasons. The presence of gastric and esophageal cancer, Barrett's esophagus, neuroendocrine tumors (NETs), gastrointestinal stromal tumors (GISTs), gastric adenomas, and ampullary tumors was assessed. The results showed that 4/340 (1.2%) of the IPMN patients had gastric cancer and 1/340 (0.3%) had esophageal cancer. The matched control group had a similar incidence of gastric cancer (5/340) (1.5%), with no esophageal cancer cases (p > 0.999). The overall incidence of other esophagogastroduodenal conditions did not significantly differ between the IPMN patients and the controls. However, the incidence of gastric cancer in the IPMN patients was higher than expected based on national cancer registry data (standardized incidence ratio of 31.39; p < 0.001; CI 8.38-78.76). In conclusion, IPMN patients have a significantly higher incidence of gastric cancer compared to the general population. However, the incidence of esophagogastroduodenal findings, including gastric and esophageal cancer, is similar between IPMN patients and those who undergo an EGD for similar clinical indications. Further research is needed to determine optimal surveillance strategies for IPMN patients regarding their risk of developing gastric cancer.

A Purified Aspartic Protease from Akkermansia Muciniphila Plays an Important Role in Degrading Muc2

Akkermansia muciniphila can produce various mucin-degrading proteins. However, the functional characteristics of these proteins and their role in mucin degradation are unclear. Of the predicted protein-coding genes, Amuc_1434, which encodes for a hypothetical protein, is the focus in this study. A recombinant enzyme Amuc_1434 containing the 6× His-tag produced in Escherichia coli (hereinafter termed Amuc_1434*) was isolated to homogeneity and biochemically characterised. Results showed that the enzyme can hydrolyse hemoglobin with an activity of 17.21 U/μg. The optimal pH and temperature for hemoglobin hydrolysis of Amuc_1434* were found to be around 8.0 and 40 °C, respectively. Amuc_1434* is identified as a member of the aspartic protease family through the action of inhibitor pepstatin A. Amuc_1434* promotes the adhesion of colon cancer cell line LS174T, which can highly express Muc2. Significantly Amuc_1434* can degrade Muc2 of colon cancer cells. Amuc_1434 is mainly located in the colon of BALB/c mice. These results suggest that the presence of Amuc_1434 from Akkermansia muciniphila may be correlated with the restoration of gut barrier function by decreasing mucus layer thickness.

Prevalence of Extrapancreatic Malignancies Among Patients With Intraductal Papillary Mucinous Neoplasms of the Pancreas

OBJECTIVES

We conducted a study in order to assess the prevalence of extrapancreatic malignancies (EPMs) in a cohort of patients with intraductal papillary mucinous neoplasms (IPMNs) from northeastern Italy.

METHODS

A study was conducted in hospital Santa Maria della Misericordia, Udine, Italy. Hospital records were screened in order to identify newly diagnosed IPMN cases in the period from January 1, 2009, to December 31, 2015. We searched for EPMs diagnosed previous to, synchronous to, or after the IPMN. The ratio of the observed (O) number of patients with EPMs to the expected (E) was calculated.

RESULTS

We identified 72 EPMs in 63 (31.8%) of 198 patients included. Among them, 51 (70.8%) were diagnosed previous to, 17 (23.6%) synchronous to, and 4 (5.6%) after the IPMN. Most frequently diagnosed were colorectal (12 patients [6.1%]), breast (8 patients [6.8%, in females]), renal cell (8 patients [4.0%]), and prostate cancer (7 patients [8.6%, in males]). The O/E ratios for EPMs were significantly increased for cancer in general (3.66; 95% confidence interval [CI], 2.39-5.37), renal cell (9.62; 95% CI, 1.98-28.10), prostate (4.91; 95% CI, 1.59-11.45), and breast cancer (3.16; 95% CI, 1.03-7.37).

CONCLUSIONS

We report an increased risk of EPMs in patients with IPMN, especially for renal cell, prostate, colorectal, and breast cancer.

Revisions of international consensus Fukuoka guidelines for the management of IPMN of the pancreas

The management of intraductal papillary mucinous neoplasm (IPMN) continues to evolve. In particular, the indications for resection of branch duct IPMN have changed from early resection to more deliberate observation as proposed by the international consensus guidelines of 2006 and 2012. Another guideline proposed by the American Gastroenterological Association in 2015 restricted indications for surgery more stringently and recommended physicians to stop surveillance if no significant change had occurred in a pancreatic cyst after five years of surveillance, or if a patient underwent resection and a non-malignant IPMN was found. Whether or not it is safe to do so, as well as the method and interval of surveillance, has generated substantial debate. Based on a consensus symposium held during the meeting of the International Association of Pancreatology in Sendai, Japan, in 2016, the working group has revised the guidelines regarding prediction of invasive carcinoma and high-grade dysplasia, surveillance, and postoperative follow-up of IPMN. As the working group did not recognize the need for major revisions of the guidelines, we made only minor revisions and added most recent articles where appropriate. The present guidelines include updated information and recommendations based on our current understanding, and highlight issues that remain controversial or where further research is required.

Intraductal Papillary Mucinous Neoplasm of Pancreas

Intraductal papillary mucinous neoplasms (IPMNs) of the pancreas are neoplasms that are characterized by ductal dilation, intraductal papillary growth, and thick mucus secretion. This relatively recently defined pathology is evolving in terms of its etiopathogenesis, clinical features, diagnosis, management, and treatment guidelines. A PubMed database search was performed. All the relevant abstracts in English language were reviewed and the articles in which cases of IPMN could be identified were further scrutinized. Information of IPMN was derived, and duplication of information in several articles and those with areas of persisting uncertainties were excluded. The recent consensus guidelines were examined. The reported incidence of malignancy varies from 57% to 92% in the main duct-IPMN (MD-IPMN) and from 6% to 46% in the branch duct-IPMN (BD-IPMN). The features of high-risk malignant lesions that raise concern include obstructive jaundice in a patient with a cystic lesion in the pancreatic head, the findings on radiological imaging of a mass lesion of >30 mm, enhanced solid component, and the main pancreatic duct (MPD) of size ≥10 mm; while duct size 5-9 mm and cyst size <3 mm are considered as “worrisome features.” Magnetic resonance imaging (MRI) and endoscopic ultrasound (EUS) are primary investigations in diagnosing and following up on these patients. The role of pancreatoscopy and the analysis of aspirated cystic fluid for cytology and DNA analysis is still to be established. In general, resection is recommended for most MD-IPMN, mixed variant, and symptomatic BD-IPMN. The 5-year survival of patients after surgical resection for noninvasive IPMN is reported to be at 77-100%, while for those with invasive carcinoma, it is significantly lower at 27-60%. The follow-up of these patients could vary from 6 months to 1 year and would depend on the risk stratification for invasive malignancy and the pathology of the resected specimen. The understanding of IPMN has evolved over the years. The recent guidelines have played a role in this regard.

Increased risk of second malignancy in pancreatic intraductal papillary mucinous tumors: Review of the literature

AIM: To analyze the available evidence about the risk of extrapancreatic malignancies and pancreatic ductal adenocarcinoma associated to pancreatic intraductal papillary mucinous tumors (IPMNs).

METHODS: A systematic search of literature was undertaken using MEDLINE, EMBASE, Cochrane and Web-of-Science libraries. No limitations for year of publication were considered; preference was given to English papers. All references in selected articles were further screened for additional publications. Both clinical series and Literature reviews were selected. For all eligible studies, a standard data extraction form was filled in and the following data were extracted: study design, number of patients, prevalence of pancreatic cancer and extrapancreatic malignancies in IPMN patients and control groups, if available.

RESULTS: A total of 805 abstracts were selected and read; 25 articles were considered pertinent and 17 were chosen for the present systematic review. Eleven monocentric series, 1 multicentric series, 1 case-control study, 1 population-based study and 3 case report were included. A total of 2881 patients were globally analyzed as study group, and the incidence of pancreatic cancer and/or extrapancreatic malignancies ranged from 5% to 52%, with a mean of 28.71%. When a control group was analyzed (6 papers), the same incidence was as low as 9.4%.

CONCLUSION: The available Literature is unanimous in claiming IPMNs to be strongly associated with pancreatic and extrapancreatic malignancies. The consequences in IPMNs management are herein discussed.

Pancreatic intraductal papillary mucinous neoplasm in a patient with Lynch syndrome

Intraductal papillary mucinous neoplasm (IPMN) is a mucin-producing epithelial neoplasm that carries a risk of progression to invasive pancreatic ductal adenocarcinoma. Lynch syndrome is an autosomal dominant condition caused by germline mutations in mismatch repair genes such as MSH2 that lead to microsatellite instability and increased risk of tumor formation. Although families with Lynch syndrome have an increased risk of pancreatic cancer, a clear connection between Lynch syndrome and IPMN has not been drawn. We present a report of a 58 year-old Caucasian woman with multiple cancers and a germline mutation of MSH2 consistent with Lynch syndrome. A screening abdominal computed tomography scan revealed a dilated main pancreatic duct and cystic ductular structure in the uncinate process that were consistent with IPMN of the main pancreatic duct on excision. Immunohistochemistry and polymerase chain reaction of the patient’s pancreas specimen did not reveal microsatellite instability or mismatch repair gene loss of expression or function. Our findings may be explained by the fact that loss of mismatch repair function and microsatellite instability is a late event in neoplastic transformation. Given the relative rarity of main duct IPMN, its appearance in the setting of somatic MSH2 mutation suggests that IPMN may fit into the constellation of Lynch syndrome related malignancies.

Prevalence and risk factors of extrapancreatic malignancies in a large cohort of patients with intraductal papillary mucinous neoplasm (IPMN) of the pancreas

BACKGROUND

The objectives of this study are to estimate prevalence and incidence of extrapancreatic malignancies (EPMs) among intraductal papillary mucinous neoplasms (IPMNs) of the pancreas, and to identify risk factors for their occurrence.

PATIENTS AND METHODS

We conducted multicentric cohort study in Italy from January 2010 to January 2011 including 390 IPMN cases. EPMs were grouped as previous, synchronous (both prevalent) and metachronous (incident). We calculated the observed/expected (O/E) ratio of prevalent EPMs, and compared the distribution of demographic, medical history and lifestyle habits.

RESULTS

Ninety-seven EPMs were diagnosed in 92 patients (23.6%), among them 78 (80.4%) were previous, 14 (14.4%) were synchronous and 5 (5.2%) were metachronous. O/E ratios for prevalent EPMs were significantly increased for colorectal carcinoma (2.26; CI 95% 1.17-3.96), renal cell carcinoma (6.00; CI 95% 2.74-11.39) and thyroid carcinoma (5.56; CI 95% 1.80-12.96). Increased age, heavy cigarette smoking, alcohol consumption and first-degree family history of gastric cancer are significant risk factors for EPMs, while first-degree family history of colorectal carcinoma was borderline.

CONCLUSION

We report an increased prevalence of EPMs in Italian patients with IPMN, especially for colorectal carcinoma, renal cell and thyroid cancers. A systematic surveillance of IPMN cases for such cancer types would be advised.

The silence of MUC2 mRNA induced by promoter hypermethylation associated with HBV in Hepatocellular Carcinoma

Background

To evaluate the promoter methylation status of MUC2 gene and mRNA expression in patients with hepatocellular carcinoma.

Methods

We analyzed MUC2 methylation by MSP, and MUC2 mRNA by real-time PCR in 74 HCC.

Results

MUC2 mRNA were lower in HCC tissues (Mean _-ΔCt = −4.70) than that in Non-HCC tissues (Mean _-ΔCt = −2.98). Expression of MUC2 was elevated in only 23 (31.08%) of the 74 HCC patients. MUC2 promoter was hypermethylated in 62.2% (46/74) of HCCs, and in only 18.9% (14/74) of non-tumor samples. MUC2 mRNA were lower in HCC patients with hypermethylation (Mean _-ΔΔCt = −2.25) than those with demethylation (Mean _-ΔΔCt = −0.22), and there is a decreased tendency for MUC2 mRNA in HCC patients with promoter hypermethylation (p = 0.011). There was a significantly correlation found between MUC2 mRNA and HBV and AFP in HCC. The loss of MUC2 mRNA and hypermethylation could be poor prognostic factors. After treated by 5-Aza-CdR and TSA, we found that MUC2 mRNA induced significantly in 7721, Huh7 and HepG2 cells.

Conclusion

The results suggested that MUC2 mRNA silenced by promoter hypermethylation is associated with high levels HBV in HCC.

International consensus guidelines 2012 for the management of IPMN and MCN of the pancreas

The international consensus guidelines for management of intraductal papillary mucinous neoplasm and mucinous cystic neoplasm of the pancreas established in 2006 have increased awareness and improved the management of these entities. During the subsequent 5 years, a considerable amount of information has been added to the literature. Based on a consensus symposium held during the 14th meeting of the International Association of Pancreatology in Fukuoka, Japan, in 2010, the working group has generated new guidelines. Since the levels of evidence for all items addressed in these guidelines are low, being 4 or 5, we still have to designate them "consensus", rather than "evidence-based", guidelines. To simplify the entire guidelines, we have adopted a statement format that differs from the 2006 guidelines, although the headings are similar to the previous guidelines, i.e., classification, investigation, indications for and methods of resection and other treatments, histological aspects, and methods of follow-up. The present guidelines include recent information and recommendations based on our current understanding, and highlight issues that remain controversial and areas where further research is required.

Branch-type intraductal papillary mucinous neoplasms: an update

BACKGROUND/AIMS

Branch-type intraductal papillary mucinous neoplasms (BT-IPMNs) are a subset of non-inflammatory mucinous lesions of the pancreas. Selected BT-IPMNs can be managed conservatively by surveillance because of their lower malignant potential. This review aims to update the reader on advances in our knowledge of BT-IPMNs since the consensus guidelines published in 2006.

METHODS

A Pubmed search for BT-IPMNs was undertaken and relevant papers were reviewed.

RESULTS

Due to the relative scarcity of this condition, still little is known about the natural history, the best method of surveillance or the surgical and non-surgical options.

CONCLUSION

A national database of BT-IPMNs would enable a large enough cohort of patients to be followed up and valid conclusions drawn regarding the best method of treatment or surveillance. and IAP.

Predictive factors associated with malignancy of intraductal papillary mucinous pancreatic neoplasms

AIM: To identify preoperative predictive factors associated with malignancy of intraductal papillary mucinous neoplasms (IPMNs) of the pancreas.

METHODS: Between April 1995 and April 2010, 129 patients underwent surgical resection for IPMNs at our institute and had confirmed pathologic diagnoses. The medical records were retrospectively reviewed and immunohistochemical staining for mucin (MUC) in pancreatic tissues was performed.

RESULTS: Univariate analysis showed that the following five variables were closely associated with malignant IPMNs preoperatively: absence of extrapancreatic malignancy; symptoms; tumor size > 4 cm; main pancreatic duct (MPD) size > 7 mm; and lymph node enlargement on preoperative computed tomography (CT). Multivariate analysis revealed that the following two factors were significantly associated with malignant IPMNs preoperatively: MPD size > 7 mm [odds ratio (OR) = 2.50]; and lymph node enlargement on preoperative CT (OR = 3.57). No significant differences in the expression of MUC1, MUC2 and MUC5AC were observed between benign and malignant IPMNs.

CONCLUSION: MPD size > 7 mm and preoperative lymph node enlargement on CT are useful predictive factors associated with malignancy of IPMNs.

Extrapancreatic malignancies and intraductal papillary mucinous neoplasms of the pancreas

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

Frequency of extrapancreatic neoplasms in intraductal papillary mucinous neoplasm of the pancreas: implications for management

OBJECTIVE

To estimate the frequency of extrapancreatic neoplasms in patients with IPMN compared with those with ductal pancreatic cancer and a general referral population.

SUMMARY BACKGROUND DATA

Several studies have reported an increased risk of extrapancreatic neoplasms in patients with IPMN, but these studies focused only on those patients who underwent resection and excluded those patients treated nonoperatively.

METHODS

All patients diagnosed with IPMN at Mayo Clinic from 1994 to 2006 were identified. Two control groups consisting of Group 1-patients with a diagnosis of ductal pancreatic adenocarcinoma (1:1) and Group 2-a general referral population (3:1) were matched for gender and age at diagnosis, year of registration, and residence. Logistic regression was used to assess the risk of a diagnosis of extrapancreatic neoplasms among cases versus controls.

RESULTS

There were 471 cases, 471 patients in Group 1, and 1413 patients in Group 2. The proportion of IPMN patients having any extrapancreatic neoplasm diagnosed before or coincident to the index date was 52% (95% CI, 47%-56%), compared with 36% (95% CI, 32%-41%) in Group 1 (P < 0.001), and 43% (95% CI, 41%-46%) in Group 2 (P = 0.002). Benign neoplasms most frequent in the IPMN group were colonic polyps (n = 114) and Barrett's neoplasia (n = 18). The most common malignant neoplasms were nonmelanoma skin (n = 35), breast (n = 24), prostate (n = 24), colorectal cancers (n = 19), and carcinoid neoplasms (n = 6).

CONCLUSIONS

Patients with IPMN have increased risk of harboring extrapancreatic neoplasms. Based on the frequency of colonic polyps, screening colonoscopy should be considered in all patients with IPMN.

Extrapancreatic malignancies in patients with intraductal papillary mucinous neoplasm of the pancreas: prevalence, associated factors, and comparison with patients with other pancreatic cystic neoplasms

BACKGROUND

Intraductal papillary mucinous neoplasm (IPMN) of the pancreas is reported to have a high prevalence of extrapancreatic malignancy (EPM). The aims of this study were to evaluate the prevalence and associated factors of EPMs in IPMN patients and to compare these data with those of non-IPMN pancreatic cystic neoplasm (PCN) patients.

METHODS

The study included 385 PCN patients (210 IPMNs and 175 non-IPMNs) diagnosed from 1993 to 2007. PCN types, presence of EPMs, chronological relation of EPMs to PCN diagnosis, and their clinicopathological parameters were analyzed.

RESULTS

The prevalence of EPM was 33.8% for IPMNs and 12.0% for non-IPMN PCNs (P < 0.001). In the majority of patients with EPMs, PCNs were detected while undergoing workup for the EPMs. For IPMNs, age was associated with EPMs [odds ratio (OR) 1.05, P = 0.013]; malignant IPMN showed a borderline inverse association with EPMs (OR 0.50, P = 0.071). Multivariate analysis of entire PCN cohort demonstrated that age at PCN diagnosis (OR 1.05, P < 0.001) was positively associated with EPM; IPMN showed a borderline positive association with EPM (OR 1.88, P = 0.052). Malignant PCN (OR 0.40, P = 0.009) was inversely associated with EPM.

CONCLUSION

The EPM prevalence of IPMN patients was 33.8%. Advanced age at IPMN diagnosis was the only factor significantly associated with EPMs in our IPMN cohort. In our PCN cohort, advanced age at PCN diagnosis was associated with malignant PCN and IPMN showed a borderline positive association with EPM.

Intraductal papillary mucinous neoplasms

Intraductal papillary mucinous neoplasm (IPMN) is characterized by enhanced mucus secretion. It is a benign or low-grade neoplasm associated with a dilated main pancreatic duct, patulous ampullary orifice, and abundant mucus secretion. Foci of aggressive cancer may arise and become invasive. Surgery is the only treatment that can cure IPMN, but the extent of pancreatic resection and the intraoperative margins remain areas of controversy. The risks of total pancreatectomy must be weighed against the risk for developing cancer in the residual pancreas. Risks must be factored against the natural course of the disease and the likelihood of malignancy developing over the life expectancy.

Intraductal papillary mucinous neoplasms of the pancreas

Intraductal papillary mucinous neoplasms (IPMNs) of the pancreas are now a well-recognized category of slowly growing tumors with a remarkably better prognosis, even when malignant, than pancreatic ductal adenocarcinoma. Their clinical and pathohistologic features have been increasingly attracting the attention of clinicians since their first description 25 years ago. Despite its burgeoning volume recently, accumulated literature devoted to IPMN still provides a low level of evidence with regard to diagnosis, treatment, and prognosis. Therefore, we performed a Medline-based systematic review of the literature aimed at clearly defining the clinicopathologic characteristics of pancreatic IPMN and determining the best currently available evidence-based principles of diagnosis and management of patients with this disease.