How does intestinal-type intraductal papillary mucinous neoplasm emerge? CDX2 plays a critical role in the process of intestinal differentiation and progression

Intestinal-type intraductal papillary mucinous neoplasm (IPMN) of the pancreas is clinicopathologically distinctive. Our research aimed to elucidate the molecular mechanism of the development and progression of the intestinal-type IPMN. In 60 intestinal-type IPMN specimens, histological transitions from gastric-type epithelia to intestinal-type epithelia were observed in 48 cases (80%). CDX2/MUC2/alcian blue triple staining indicated that CDX2 appeared to precede MUC2 expression and subsequent alcian blue-positive mucin production. Expression of p21 and Ki-67 seemed to be accelerated by CDX2 expression (p = 6.02e-13 and p = 3.1e-09, respectively). p21/Ki-67 double staining revealed that p21 was mostly expressed in differentiated cells in the apex of papillae, while Ki-67 was expressed in proliferative cells in the base of papillae. This clear cellular arrangement seemed to break down with the progression of atypical grade and development of invasion (p = 0.00197). Intestinal-type IPMNs harbored frequent GNAS mutations (100%, 25/25) and RNF43 mutations (57%, 8/14) and shared identical GNAS and KRAS mutations with concurrent gastric-type IPMNs or incipient gastric-type neoplasia (100%, 25/25). RNF43 mutations showed emerging or being selected in intestinal-type neoplasms along with ß-catenin aberration. Activation of protein kinase A and extracellular-regulated kinase was observed in CDX2-positive intestinal-type neoplasm. These results suggest that gastric-type epithelia that acquire GNAS mutations together with induction of intrinsic CDX2 expression may evolve with clonal selection and additional molecular aberrations including RNF43 and ß-catenin into intestinal-type IPMNs, which may further progress with complex villous growth due to disoriented cell cycle regulation, acceleration of atypical grade, and advance to show an invasive phenotype.

Evolution of the immune landscape during progression of pancreatic intraductal papillary mucinous neoplasms to invasive cancer

BACKGROUND

Intraductal papillary mucinous neoplasms (IPMNs) are precursor lesions of pancreatic cancer, which is characterized by an immunosuppressive microenvironment. Yet, the spatial distribution of the immune infiltrate and how it changes during IPMN progression is just beginning to be understood.

METHODS

We obtained tissue samples from patients who underwent pancreatic surgery for IPMN, and performed comprehensive immunohistochemical analyses to investigate the clinical significance, composition and spatial organization of the immune microenvironment during progression of IPMNs. Survival analysis of pancreatic cancer patients was stratified by tumour infiltrating immune cell subtypes.

FINDINGS

The immune microenvironment evolves from a diverse T cell mixture, comprising CD8⁺ T cells, Th/c1 and Th/c2 as major players combined with Th9, Th/c17, Th22, and Treg cells in low-grade IPMN, to a Treg dominated immunosuppressive state in invasive pancreatic cancer. Organized lymphoid clusters formed in IPMN surrounding stroma and accumulated immunosuppressive cell types during tumour progression. Survival of pancreatic cancer patients correlated with Th2 signatures in the tumour microenvironment.

INTERPRETATION

The major change with regards to T cell composition during IPMN progression occurs at the step of tissue invasion, indicating that malignant transformation only occurs when tumour immune surveillance is overcome. This suggests that novel immunotherapies that would boost spontaneous antitumor immunity at premalignant states could prevent pancreatic cancer development.

FUNDING

The present work was supported by German Cancer Aid grants (70,112,720 and 70,113,167) to S. R., and the Olympia Morata Programme of the Medical Faculty of Heidelberg University to S. R.

Similarities and differences in guidelines for the management of pancreatic cysts

Accurate diagnosis of Pancreatic cysts (PC) is key in the management. The knowledge of indications for surgery, the role of endoscopic ultrasound-guided fine needle aspiration, cyst fluid analysis, imaging, and surveillance of PC are all important in the diagnosis and management of PC. Currently, there are many guidelines for the management of PC. The optimal use of these guidelines with a patient-centered approach helps diagnose early cancer and prevent the spread of cancer.

Branch Duct Intraductal Papillary Mucinous Neoplasms: Recommendations for Follow-Up and Surgery

BACKGROUND AND AIMS

Pancreatic cysts are increasingly diagnosed, mainly during abdominal imaging performed for other reasons. Between pancreatic cystic neoplasm, intraductal papillary mucinous neoplasms are the most common pre-malignant entities. Intraductal papillary mucinous neoplasms involving side branches overall harbor a low risk of malignancy, and in the recent past, a progressively more conservative approach has been consolidated. Purpose of this report is to summarize the evidence supporting the current practice for the management of branch duct intraductal papillary mucinous neoplasm and to offer a useful practical guide from first observation to post-operative follow-up.

MATERIALS AND METHODS

Review of the most important scientific literature on intraductal papillary mucinous neoplasms was made. In this review article, we also report the experience of a high volume center in managing Pancreatic cystic neoplasms.

RESULTS

The correct management during surveillance still is a matter of debate, since many guidelines have been published suggesting different clinical approaches. Recently, follow-up discontinuation has also been proposed in selected cases.

CONCLUSION

Despite significant improvements made by the increase of evidence, selecting surgical candidates because of an increased risk of malignant progression remains an unsolved issue and a hot topic for pancreatologists.

Subtype of intraductal papillary mucinous neoplasm of the pancreas is important to the development of metachronous high-risk lesions after pancreatectomy

Backgrounds/Aims

Although intraductal papillary mucinous neoplasm (IPMN) has showed a favorable prognosis compared to pancreatic ductal adenocarcinoma, its recurrence patterns have somewhat questionable in detail. After partial pancreatectomy for IPMN, the evaluation for risk of metachronous occurrence of high-risk lesions (HRL) in the residual pancreas is important to establish a postoperative surveillance modality and duration of follow-up. This study aimed to evaluate the factors that may predict the metachronous occurrence of HRL in the remnant pancreas after surgery of the IPMN.

Methods

From 2005 to 2016, clinicopathologic and surveillance data for 346 consecutive patients who underwent surgical resection for IPMN were reviewed retrospectively. Histologic subtype was classified as gastric, intestinal, pancreato-biliary, or oncocytic type.

Results

All of IPMN were classified as main duct (n=64, 18.5%), branch duct (n=171, 49.4%), and mixed type (n=111, 32.1%). Forty-eight patients (13.9%) experienced recurrence during follow-up. Among these, 9 patients (2.6%) were identified to metachronous development of HRL in the remnant pancreas. After multivariate analysis, high-grade dysplasia (HGD) or invasive carcinoma (IC) compared to low- or intermediate dysplasia was only independent risk factor for recurrence (HR 3.688, 95% CI 2.124– 12.524, p=0.009). The independent risk factors for metachronous development were HGD/IC (HR 8.414, 95% CI 4.310– 16.426, p=0.001), and intestinal/pancreato-biliary subtype compared to gastric subtype (HR 7.874, 95% CI 3.650– 27.027, p=0.010).

Conclusions

Patients with high-grade dysplasia or invasive carcinoma, and with intestinal or pancreatobiliary subtype should undergo close, long-term surveillance of the remnant pancreas after initial resection.

Predictive Value of Localized Stenosis of the Main Pancreatic Duct for Early Detection of Pancreatic Cancer

Background/Aims:

In this study, we aimed to evaluate the predictive value of localized stenosis of the main pancreatic duct (MPD) for early detection of pancreatic cancer.

Methods:

Among 689 patients who underwent endoscopic retrograde pancreatography from January 2008 to September 2018, 19 patients with MPD findings were enrolled. These patients showed findings for indicating suspicious pancreatic cancer at an early stage (FiCE); FiCE was defined as a single, localized stenosis in the MPD without a detectable mass (using any other imaging methods) and without other pancreatic diseases, such as definite chronic pancreatitis, intraductal papillary mucinous neoplasm, and autoimmune pancreatitis. Final diagnoses were established by examining resected specimens or through follow-up examinations after an interval of >5 years.

Results:

Among 19 patients with FiCE, 11 underwent surgical resection and 8 were evaluated after a >5-year observation period. The final diagnosis of the MPD stenosis was judged to be pancreatic cancer in 9 patients (47%), including 3 with intraepithelial cancer, and to be a non-neoplastic change in 10. The sensitivity, specificity, and accuracy of preoperative pancreatic juice cytology were 75%, 100%, and 88%, respectively.

Conclusions:

The predictive value of FiCE for pancreatic cancer prevalence was 47%. Histological confirmation with pancreatic juice cytology is necessary before surgical resection.

Carcinoembryonic antigen level in the pancreatic juice is effective in malignancy diagnosis and prediction of future malignant transformation of intraductal papillary mucinous neoplasm of the pancreas

BACKGROUND

The present study aimed to determine the ability of diagnosing malignancy and predicting malignant transformation in patients with IPMN using carcinoembryonic antigen (CEA) level in the pancreatic juice.

METHODS

We enrolled patients with IPMN who underwent endoscopic retrograde pancreatography (ERP) between 2002 and 2018. We examined the ability of diagnosing malignancy in 63 patients who underwent surgery (surgical group). Furthermore, we examined the value of predicting malignant transformation in 52 patients who underwent follow-up for over 1 year after ERP (follow-up group).

RESULTS

In the surgical group, the overall sensitivity and specificity of CEA level (≥ 97 ng/ml) in the pancreatic juice for diagnosing malignancy were 45% and 100%, respectively. The specificity was excellent for all IPMN types; however, the sensitivity was highest in main duct type, followed by mixed type and branch duct type. In the follow-up group, malignant transformation was observed in four patients (7.7%) during the follow-up, and the median time until malignant transformation was 58 months. High CEA level in the pancreatic juice demonstrated a statistically significant difference in multivariate analysis and was found to be an independent predictor of malignant transformation (hazard ratio 17; P = 0.02). The cumulative malignant transformation rate was significantly higher in the high CEA group than that in the low CEA group (5-year cumulative malignant transformation rates, 69% vs. 0%, P < 0.001).

CONCLUSIONS

Carcinoembryonic antigen level in the pancreatic juice is useful not only in diagnosing malignancy but also in predicting future malignant transformations in IPMN patients receiving follow-up.

Endoscopic ultrasonography for the evaluation of pancreatic cystic neoplasms

Endoscopic ultrasonography (EUS) is a modality with high spatial resolution that enables comprehensive observation of the entire pancreas and plays an important role in the diagnosis of pancreatic lesions. Recent advances in diagnostic imaging methods such as ultrasound, computed tomography, and magnetic resonance imaging have increased the incidental detection of pancreatic cystic lesions (PCLs). EUS has been recognized as an essential diagnostic method for the detection and evaluation of PCLs. EUS has two important roles: as a detailed (high-resolution) imaging diagnostic method and as an approach for collecting cyst fluid content by EUS-guided fine needle aspiration for pathological diagnosis or biomarker evaluation. Furthermore, in recent years, the usefulness of contrast-enhanced EUS for the differential diagnosis of PCLs or evaluation of grade of malignancy, and a novel imaging technique called needle-based confocal laser endomicroscopy to observe intraductal structures through a needle, has been reported. An understanding of the morphological characteristics of PCLs depicted by ultrasound imaging and of the benefits and limitations of EUS diagnosis in daily practice is needed.

Hyperthermic intraperitoneal chemotherapy in management of malignant intraductal papillary mucinous neoplasm with peritoneal dissemination: Case report

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IPMN is not a common disease, has low risk to develop invasive lesion. But when invasion occurred, the prognosis is poor.

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Malignant IPMN with peritoneal dissemination also has poor prognosis.

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CRS and HIPEC can prolong survival in malignant IPMN with peritoneal dissemination patient.

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Pseudomyxoma peritonei can be found as rare manifestation of IPMN, that can associate with tumor rupture form diagnostic procedure like EUS-FNA or surgical procedure.

Introduction

Cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC) are treatment to deal with peritoneal dissemination that has excellent result for various cancer especially pseudomyxoma peritonei (PMP), mesothelioma. For now, this combination of treatment is still running for pancreatic adenocarcinoma but no description for pancreatic cystic tumor like malignant Intraductal papillary mucinous neoplasm (IPMN).

Presentation of cases

We report 3 cases of malignant IPMN with peritoneal dissemination that treated with CRS and HIPEC. Two cases have atypical presentation of malignant IPMN with PMP. HIPEC was performed using cisplatin-based regimen. The longest survival in this study is 93 months, compared to the median survival of 44.3 months without HIPEC.

Discussion

CRS and HIPEC have not proven to treat in patient with pancreatic cystic tumor with peritoneal dissemination. But these treatments can be improved survival outcome in selected patient.

Conclusion

CRS and HIPEC trend to improve survival. More studies need, not only to evaluate the role of HIPEC on malignant IPMN, but also prognosis and outcome.

Performance of candidate urinary biomarkers for pancreatic cancer - Correlation with pancreatic cyst malignant progression?

BACKGROUND

Intraductal papillary mucinous neoplasms (IPMN) are precursors of pancreatic cancer. Potential biomarkers of IPMN progression have not been identified in urine. A few urinary biomarkers were reported to be predictive of pancreatic ductal adenocarcinoma (PDAC). Here, we seek to assess their ability to detect high-risk IPMN.

METHODS

Urine was collected from patients undergoing pancreatic resection and healthy controls. TIMP-1(Tissue Inhibitor of Metalloproteinase-1), LYVE-1(Lymphatic Vessel Endothelial Receptor 1), and PGEM(Prostaglandin E Metabolite) levels were determined by ELISA and analyzed by Kruskal-Wallis.

RESULTS

Median urinary TIMP-1 levels were significantly lower in healthy controls (n = 9; 0.32 ng/mg creatinine) compared to PDAC (n = 13; 1.95) but not significantly different between low/moderate-grade (n = 20; 0.71) and high-grade/invasive IPMN (n = 20; 1.12). No significant difference in urinary LYVE-1 was detected between IPMN low/moderate (n = 16; 0.37 ng/mg creatinine) and high/invasive grades (n = 21; 0.09). Urinary PGEM levels were not significantly different between groups.

CONCLUSIONS

Urinary TIMP-1, LYVE-1, and PGEM do not correlate with malignant potential of pancreatic cysts.

Role of endoscopic ultrasound in the screening and follow-up of high-risk individuals for familial pancreatic cancer

Managing familial pancreatic cancer (FPC) is challenging for gastroenterologists, surgeons and oncologists. High-risk individuals (HRI) for pancreatic cancer (PC) (FPC or with germline mutations) are a heterogeneous group of subjects with a theoretical lifetime cumulative risk of PC over 5%. Screening is mainly based on annual magnetic resonance imaging (MRI) and endoscopic ultrasound (EUS). The goal of screening is to identify early-stage operable cancers or high-risk precancerous lesions (pancreatic intraepithelial neoplasia or intraductal papillary mucinous neoplasms with high-grade dysplasia). In the literature, target lesions are identified in 2%-5% of HRI who undergo screening. EUS appears to provide better identification of small solid lesions (0%-46% of HRI) and chronic-pancreatitis-like parenchymal changes (14%-77% of HRI), while MRI is probably the best modality to identify small cystic lesions (13%-49% of HRI). There are no specific studies in HRI on the use of contrast-enhanced harmonic EUS. EUS can also be used to obtain tissue samples. Nevertheless, there is still limited evidence on the accuracy of imaging procedures used for screening or agreement on which patients to treat. The cost-effectiveness of screening is also unclear. Certain new EUS-related techniques, such as searching for DNA abnormalities or protein markers in pancreatic fluid, appear to be promising.

Role of Ancillary Testing on Endoscopic US-Guided Fine Needle Aspiration Samples from Cystic Pancreatic Neoplasms

Pancreatic cysts are increasingly detected on imaging studies. Accurate determination of the cyst type is important to provide appropriate care for the patients. It is also very clear that not one single modality can provide adequate diagnostic information. A multidisciplinary approach is the key to the diagnosis of pancreatic cysts. In this setting, the role of ancillary testing, which includes biochemical testing (carcinoembryonic antigen and amylase levels in the cyst), molecular testing (e.g., KRAS, GNAS, VHL, and CTNB1), and/or immunohistochemical tests are very important to obtain an accurate diagnosis. This review will discuss helpful ancillary tests in common pancreatic cyst neoplasms and how to approach the diagnosis of pancreatic cysts.

Pancreatic Intraductal Papillary Mucinous Neoplasm With Elevated Pre-Operative Cystic Carcinoembryonic Antigen Level: A Histopathologic Correlation

Background

To study the relationship between carcinoembryonic antigen (CEA) level, intraductal papillary mucinous neoplasm (IPMN) subtype, and the presence of invasive carcinoma.

Methods

Cystic CEA level and the following pathologic variables: subtypes of IPMN, size of cystic lesion, presence of dysplasia or carcinoma, and main or branch duct involvement from 45 IPMN cases were analyzed.

Results

There was a significant correlation between pre-operative cystic fluid CEA level and the intensity of luminal CEA staining. However, there was no correlation between CEA level and cystic mucinous secretions or mucinous epithelial cytoplasm CEA staining, mucin glycoprotein expression, size of lesion, grade of dysplasia or presence of invasive carcinoma. CEA level was neither sensitive nor specific for the presence of invasive carcinoma.

Conclusions

Cystic CEA level may not be a reliable determinant of the presence or absence of invasive carcinoma in IPMNs, and its use to assess risk of malignancy may be limited.

AJCC 7th edition staging classification is more applicable than AJCC 8th edition staging classification for invasive IPMN

Background

Both the 7th and 8th editions of the American Joint Committee on Cancer (AJCC) staging systems have been introduced for pancreatic adenocarcinoma. However, the applicability of these classifications for invasive intraductal papillary mucinous neoplasms (IPMN) has not been systematically examined.

Methods

Patients with invasive IPMN were retrieved from a cohort of 18 geographical sites (1973–2014 varying) in the Surveillance, Epidemiology, and End Results (SEER) cancer registry. The 7th and 8th editions of the AJCC staging were compared. Survival rates and multivariate analyses were computed.

Results

In total, 1216 patients with resected invasive IPMN were included. A major difference between the 7th and 8th systems is the definition of stage IIA (7th, beyond the pancreas without involvement of major arteries; 8th, maximum tumor diameter > 4 cm). The hazard ratio (HR) of stage IIA disease (versus stage IA, HR = 2.33, P < 0.001) was higher than that of stage IB disease (HR = 1.48, P = 0.087) by the 7th edition classification, whereas the HR of stage IIA disease (HR = 1.26, P = 0.232) was even lower than that of stage IB disease (HR = 1.48, P = 0.040) by the 8th edition classification. In addition, for the 8th edition staging system, tumor size was not a predictor of survival in patients with resectable tumor > 2 cm (size > 4 cm versus > 2 ≤ 4 cm, HR = 0.91, P = 0.420).

Conclusions

The AJCC 7th edition staging classification is more applicable than the 8th edition classification for invasive IPMN.

Expression of Matrix Metalloproteinases in Intraductal Papillary Mucinous Neoplasm of the Pancreas

BACKGROUND/AIM

Intraductal papillary mucinous neoplasm (IPMN) has a variety of histological and morphological appearances. Matrix metalloproteinases (MMPs) have been considered to be associated with tumor progression or poor prognosis. The aim of this study was to elucidate the molecular basis of IPMN variation in different types of lesions.

MATERIALS AND METHODS

The expression of MMP-1,2,7,9 in 51 cases of IPMN were investigated. The MMP score was calculated as the sum of the score of staining distribution and the score of the intensity staining.

RESULTS

MMP scores were correlated with histological grade, histological subtype, and type of invasion. MMP high expression groups (MMP score ≥5) had worse prognosis than low-expression groups.

CONCLUSION

MMP expression varied between different types of IPMN, a result supporting differences in molecular basis of malignancies. These considerations may be helpful for optimal management or treatment according to various types of IPMN.

High-risk lesions in the remnant pancreas: fate of the remnant pancreas after pancreatic resection for pancreatic cancer and intraductal papillary mucinous neoplasms

Progress in diagnostic modalities, surgical procedures, and multidisciplinary treatment for pancreatic diseases has increased the number of long-term survivors after pancreatic resection. Several reports have focused on high-risk lesions (HRLs), including high-grade pancreatic intraepithelial neoplasia (PanIN), pancreatic ductal adenocarcinoma, high-grade intraductal papillary mucinous neoplasm (IPMN), and IPMN with an associated invasive carcinoma, in the remnant pancreas after partial pancreatic resection for pancreatic cancer or IPMN. The etiology of HRLs in the remnant pancreas is thought to be either isolated local recurrence of the initial lesion in the remnant pancreas or a newly developed primary lesion. Although it is difficult to distinguish between local recurrence and a new primary lesion, comparison of genetic alterations between two lesions may help with this distinction. Early detection of HRLs in the remnant pancreas may improve the prognosis of patients, and several investigators have proposed predictive factors for HRLs in the remnant pancreas after partial pancreatic resection for pancreatic cancer or IPMN. The reported short- and long-term outcomes of surgical resection of HRLs in the remnant pancreas are relatively favorable. Life-long surveillance of the remnant pancreas is recommended after partial pancreatic resection for pancreatic cancer or IPMN.

Obstructive cholangitis by mucus from an intraductal papillary mucinous neoplasm with pancreatobiliary fistula treated by endoscopic septotomy and direct peroral cholangioscopy: a case report

Intraductal papillary mucinous neoplasms (IPMNs) occasionally form a fistula to adjacent organs, resulting in obstructive jaundice and cholangitis due to mucus obstruction. Although some procedures such as endoscopic nasobiliary drainage are attempted, they often do not work adequately because of high mucus viscosity. Herein, we report the case of an 87-year-old man with obstructive cholangitis treated by endoscopic septotomy and mucus suction with direct peroral cholangioscopy using conventional endoscopy. The patient incidentally showed a branched-type IPMN in the pancreatic head on computed tomography (CT) approximately 10-years ago. Although the patient's tumor had grown slowly and he occasionally developed cholangitis, he did not want surgery. He was admitted to our hospital because of cholangitis by mucus obstruction with a PB fistula. Endoscopic retrograde cholangiopancreatography (ERCP) and septotomy were performed. Septotomy made the duodenal papilla a large orifice, thereby facilitating spontaneous drainage of mucus. In addition, conventional endoscopy with a large working channel enabled direct access into the orifice and smooth mucus suction, thereby alleviating his cholangitis. In conclusion, septotomy and direct peroral cholangioscopy using conventional endoscopy could be useful to control biliary tract infection and obstructive jaundice due to mucus obstruction from an IPMNs with PB fistula.

Evaluation of efficacy of pancreatic juice cytology for risk classification according to international consensus guidelines in patients with intraductal papillary mucinous neoplasm; a retrospective study

OBJECTIVES

Pancreatic juice cytology (PJC) for intraductal papillary mucinous neoplasm (IPMN) is a possible tool to enhance preoperative diagnostic ability by improving risk classification for malignant IPMN, but its efficacy is controversial. This study evaluated the efficacy of PJC for risk classification according to international guidelines.

METHODS

We retrospectively analyzed 127 IPMN patients who underwent endoscopic retrograde cholangiopancreatography (ERCP) preoperatively. PJC was performed in 125 of the 127 cases. High-risk stigmata (HRS, n = 57), worrisome features (WF, n = 64), and other characteristics (n = 6) were classified according to the 2017 international guidelines.

RESULTS

Among the 127 IPMN patients, 71 (55.9%) had malignant IPMN (invasive and non-invasive intraductal papillary mucinous carcinoma). The accuracy of WF for classifying malignant IPMN was increased by the addition of PJC, but the accuracy of HRS was not (WF to WF + PJC: 33.1% [42/127] to 48.8% [61/125], HRS to HRS + PJC: 65.4% [83/127] to 52.8% [66/125]). Post-ERCP pancreatitis (PEP) occurred in 32 (25.2%) of 127 IPMN patients. Severe PEP was not detected. Significant risk factors for PEP were female sex, obesity, and endoscopic naso-pancreatic drainage (ENPD) (P = .03, P = .0006, and P = .02, respectively). In patients with ENPD tube placement, a main pancreatic duct size of <5 mm was a significant risk factor for PEP (P = .02).

CONCLUSION

PJC could increase the accuracy of WF for classifying malignant IPMN. The additive effect of PJC for risk classification may be limited, however, and it is not recommended for all IPMN cases due to the high frequency of PEP.

Blood Type as a Predictor of High-Grade Dysplasia and Associated Malignancy in Patients with Intraductal Papillary Mucinous Neoplasms

BACKGROUND

Intraductal papillary mucinous neoplasms (IPMNs) are precursor lesions to the development of pancreatic adenocarcinoma. We determined if non-O blood groups are more common in patients with IPMN and if blood group is a risk factor for progression to invasive pancreatic cancer among patients with IPMN.

METHODS

The medical records were reviewed of all patients undergoing resection of an IPMN at Johns Hopkins Hospital from June 1997 to August 2016. Potential risk factors of high-grade dysplasia and associated adenocarcinoma were identified through a multivariate logistic regression model.

RESULTS

Seven hundred and seventy-seven patients underwent surgical resection of an IPMN in which preoperative blood type was known. Sixty-two percent of IPMN patients had non-O blood groups (vs. 57% in two large US reference cohorts, P = 0.002). The association between non-O blood group was significant for patients with IPMN with low- or intermediate-grade dysplasia (P < 0.001), not for those with high-grade dysplasia (P = 0.68). Low- and intermediate-grade IPMNs were more likely to have non-type O blood compared to those with high-grade IPMN and/or associated invasive adenocarcinoma (P = 0.045). Blood type O was an independent predictor of having high-grade dysplasia without associated adenocarcinoma (P = 0.02), but not having associated invasive cancer (P = 0.72). The main risk factor for progression to invasive cancer after surgical resection was IPMN with high-grade dysplasia (P = 0.002).

CONCLUSION

IPMN patients are more likely to have non-O blood groups than controls, but type O blood group carriers had higher odds of having high-grade dysplasia in their IPMN. These results indicate blood group status may have different effects on the risk and progression of IPMNs.

Pancreatic cancer screening in patients with presumed branch-duct intraductal papillary mucinous neoplasms

Because delayed diagnosis is one of the causes of poor prognosis in pancreatic ductal adenocarcinoma (PDAC), early detection is a key for overall improvement of prognosis. Towards this end, periodic screening is recommended for individuals considered high-risk for PDAC. Advances in diagnostic imaging modalities have increased the frequency of incidental findings of pancreatic cysts, including the intraductal papillary mucinous neoplasm (IPMN) - a major risk factor of PDAC, having 1% annual prevalence of concomitance with IPMN. Proper retainment of patients with IPMN and regular follow-up by routine imaging examination will likely improve early detection and better prognosis of PDAC. Unfortunately, current guidelines only address management of PDAC derived from IPMN and overlook PDAC concomitant with IPMN. Screening of patients with IPMN, by endoscopic ultrasonography (currently the most reliable modality for detecting small PDAC), may facilitate early detection of both IPMN-derived and -concomitant PDAC. Prospective studies to evaluate the usefulness of endoscopic ultrasonography in screening of IPMN-concomitant PDAC will also help in determining the optimal surveillance strategy for more widespread applications.

Role of pancreatoscopy in management of pancreatic disease: A systematic review

BACKGROUND

Per-oral pancreatoscopy (POP) plays a role in the diagnosis and therapy of pancreatic diseases. With recent technological advances, there has been renewed interest in this modality.

AIM

To evaluate the efficacy and safety of POP in management of pancreatic stone disease and pancreatic ductal neoplasia.

METHODS

To determine the safety and efficacy of POP in the management of pancreatic diseases, a systematic search was conducted in MEDLINE, EMBASE and Ovid. Articles in languages other than English and case reports were excluded. All published case series were eligible. Data specific to POP were extracted from studies, which combined cholangiopancreatoscopy. Ten studies were included in the analysis of POP therapy for pancreatic stone disease, and 15 case series satisfied the criteria for inclusion for the role of POP in the management of pancreatic ductal neoplasia. The examined data were subcategorized according to adjunctive modalities, such as direct tissue sampling, cytology, the role of intraoperative POP, intraductal ultrasound (IDUS) and POP combined with image-enhancing technology.

RESULTS

The success rate for complete ductal stone clearance ranged from 37.5%-100%. Factors associated with failure included the presence of strictures, multiple stones and the inability to visualize the target area. Although direct visualization can identify malignant and premalignant conditions, there is significant overlap with benign diseases. Visually-directed biopsies provide a high degree of accuracy, and represent a unique approach for tissue acquisition in patients with ductal abnormalities. Addition of pancreatic fluid cytology increases diagnostic yield for indeterminate lesions. Protrusions larger than 3 mm noted on IDUS are significantly more likely to be associated with malignancy. The rate of adverse events associated with POP ranged from 0%-35%.

CONCLUSION

Current evidence supports wider adoption of pancreatoscopy, as it is safe and effective. Improved patient selection and utilization of novel technologies may further enhance its role in managing pancreatic disease.

Clinical Management and Surgical Decision-Making of IPMN of the Pancreas

Intraductal papillary mucinous neoplasm (IPMN) is the most common pancreatic cystic neoplasm (PCN). The increased attention to IPMN is due to its unique features of malignant progression, being different between main duct IPMN and branch duct IPMN, and increased de novo development of conventional pancreatic ductal adenocarcinoma elsewhere in the pancreas. The increased interest in IPMN led to publication of many guidelines on its clinical management. This chapter aims to summarize and compare characteristics of nine guidelines on the clinical management of IPMN and other PCNs published in the English literature and further to show a current strategy for surgical decision making in the management of IPMN.

Intraductal papillary mucinous neoplasm complicated by a gastropancreatic fistula

One of the rare complications of low-grade pancreatic neoplasms is fistulization into nearby structures. This often does not present clinically, but is incidentally identified in patients who have been imaged serially to monitor the progression of the disease. In this report, we present an uncommon complication of an intraductal papillary mucinous neoplasm, which developed a spontaneous gastropancreatic fistula in a patient who was conservatively managed. The clinical course, imaging features, and management of this case are discussed.

Effect of a region-wide incorporation of an algorithm based on the 2012 international consensus guideline on the practice pattern for the management of pancreatic cystic neoplasms in an integrated health system

AIM

To examine the practice pattern in Kaiser Permanente Southern California (KPSC), i.e., gastroenterology (GI)/surgery referrals and endoscopic ultrasound (EUS), for pancreatic cystic neoplasms (PCNs) after the region-wide dissemination of the PCN management algorithm.

METHODS

Retrospective review was performed; patients with PCN diagnosis given between April 2012 and April 2015 (18 mo before and after the publication of the algorithm) in KPSC (integrated health system with 15 hospitals and 202 medical offices in Southern California) were identified.

RESULTS

2558 (1157 pre- and 1401 post-algorithm) received a new diagnosis of PCN in the study period. There was no difference in the mean cyst size (pre- 19.1 mm vs post- 18.5 mm, P = 0.119). A smaller percentage of PCNs resulted in EUS after the implementation of the algorithm (pre- 45.5% vs post- 34.8%, P < 0.001). A smaller proportion of patients were referred for GI (pre- 65.2% vs post- 53.3%, P < 0.001) and surgery consultations (pre- 24.8% vs post- 16%, P < 0.001) for PCN after the implementation. There was no significant change in operations for PCNs. Cost of diagnostic care was reduced after the implementation by 24%, 18%, and 36% for EUS, GI, and surgery consultations, respectively, with total cost saving of 24%.

CONCLUSION

In the current healthcare climate, there is increased need to optimize resource utilization. Dissemination of an algorithm for PCN management in an integrated health system resulted in fewer EUS and GI/surgery referrals, likely by aiding the physicians ordering imaging studies in the decision making for the management of PCNs. This translated to cost saving of 24%, 18%, and 36% for EUS, GI, and surgical consultations, respectively, with total diagnostic cost saving of 24%.

Intraductal papillary mucinous neoplasms of the pancreas: a clinical challenge

The incidental detection rate of intraductal papillary mucinous neoplasms (IPMNs) has significantly increased. However, little is known about the natural history of these tumors. Their optimal management and appropriate follow-up are still unclear. We have, therefore, reviewed the available literature on IPMN focusing on their diagnosis, treatment according to the risk of malignant transformation, and follow-up. Areas covered: Bibliographical searches were performed in PubMed for the terms 'intraductal papillary mucinous neoplasm' and 'natural history' and 'diagnosis' and 'treatment' and 'surgery' and 'follow-up' and 'prognosis.' PubMed was used to search for all the relevant articles published over the last 10 years. A total of 7244 records were identified. After filtering for year range, English language, human studies, article types, and removing duplicates, 74 articles were left with the strongest level of evidence. Expert commentary: Available guidelines for IPMN management are mainly based on expert opinions and may lack strong evidence. Further studies are warranted to better predict the risk of recurrence/future malignancy and to establish standardized guidelines. IPMNs management should be based on multidisciplinary discussion and treatment should be tailored to an individual patient according to patient and tumor characteristics.

Histo-molecular oncogenesis of pancreatic cancer: From precancerous lesions to invasive ductal adenocarcinoma

Pancreatic cancer is a lethal malignancy, whose precursor lesions are pancreatic intraepithelial neoplasm, intraductal papillary mucinous neoplasm, intraductal tubulopapillary neoplasm, and mucinous cystic neoplasm. To better understand the biology of pancreatic cancer, it is fundamental to know its precursors and to study the mechanisms of carcinogenesis. Each of these precursors displays peculiar histological features, as well as specific molecular alterations. Starting from such pre-invasive lesions, this review aims at summarizing the most important aspects of carcinogenesis of pancreatic cancer, with a specific focus on the recent advances and the future perspectives of the research on this lethal tumor type.

Familial Pancreatic Cancer

Familial pancreatic cancer accounts for 10% of all patients with pancreatic cancer. Because the 5-year survival rate of pancreatic cancer is only 7%, screening programs for high-risk individuals are essential and might be advantageous. Pancreatic ductal adenocarcinoma mostly shows symptoms at an advanced state and treatment is not efficient enough to cure most patients. People with hereditary tumor syndromes or their affected relatives can also be included in such screening programs. Besides the collection of data to investigate the background of the disease, these screening programs aim to diagnose and treat precursor lesions so that more dangerous, invasive lesions are prevented. These precursor lesions can be pancreatic intraepithelial neoplasia, intraductal papillary mucinous neoplasm, and mucinous cystic neoplasm. This review summarizes the latest knowledge of pancreatic screening programs, shows the procedure of pancreatic cancer screening, and gives an overview of current guidelines.

Identification of nonalcoholic fatty liver disease following pancreatectomy for noninvasive intraductal papillary mucinous neoplasm

BACKGROUND

Nonalcoholic fatty liver disease (NAFLD) following pancreatectomy is a potential cause of long term morbidity in patients undergoing pancreatic resection with curative intent. Prior studies have reported an incidence of NAFLD up to 30% following pancreatectomy but the investigated cohorts were typically a mix of benign and malignant disease. Here we examined the incidence of NAFLD in a homogenous cohort of patients following pancreatectomy for benign intraductal papillary mucinous neoplasm (IPMN).

METHODS

A retrospective review of patients who underwent pancreatic resection for IPMN from 2000 to 2016 was performed. Post pancreatectomy CT/MRI scans were obtained as standard surveillance. We investigated changes in the liver parenchymal density on post surgical imaging to estimate the frequency with which NAFLD occurred. Radiographic criteria for NAFLD included Hounsfield units less than 40 on CT or liver:spleen ratio <0.9 on CT or MRI. Fischer's exact test, Kruskal-Wallis test, and logistic regression were performed.

RESULTS

Our study cohort included 109 patients who underwent pancreatectomy for nonmalignant intraductal papillary mucinous neoplasm with no evidence of NAFLD preoperatively and at least 6 months follow-up. Mean follow-up was 52 months (range 8-130/months). The incidence of postoperative NAFLD was 17/109 (15.6%). Most cases occurred within 12 months of pancreatectomy. On multivariate analysis, proximal pancreatectomy (pancreaticoduodenectomy) and development of atrophy of the pancreas remnant were significant risk factors for development of hepatic steatosis (p < 0.05).

CONCLUSION

Patients undergoing pancreatectomy for benign disease have a significant risk of developing NAFLD but the frequency is lower than previously reported in cohorts that included individuals with malignant disease. Highest risk was observed in individuals who underwent pancreaticoduodenectomy or developed pancreatic atrophy. Further investigations to define the mechanisms that promote steatosis and interventions to prevent subsequent morbidity from NAFLD are warranted.

Management of Intraductal Papillary Mucinous Neoplasms: Controversies in Guidelines and Future Perspectives

Purpose of review

Management of intraductal papillary mucinous neoplasm (IPMN) is currently based on consensus, in the absence of evidence-based guidelines. In recent years, several consensus guidelines have been published, with distinct management strategies. In this review, we will discuss these discrepancies, in order to guide treating physicians in clinical management.

Recent findings

The detection rate of pancreatic cysts has increased substantially with the expanded use of high-quality imaging techniques to up to 45%. Of these cysts, 24–82% are IPMNs, which harbour a malignant potential. Timely detection of high-risk lesions is therefore of great importance. Surgical management is based on the presence of clinical and morphological high-risk features, yet the majority of resected specimens appear to be low risk.

Summary

International collaboration and incentive large-scale prospective registries of individuals undergoing cyst surveillance are needed to accumulate unbiased data and develop evidence-based guidelines. Additionally, development of non-invasive, accurate diagnostic tools (e.g. biomarkers) is needed to differentiate between neoplastic and non-neoplastic pancreatic cysts and detect malignant transformation at an early stage (i.e. high-grade dysplasia).

Circulating Thrombospondin-2 enhances prediction of malignant intraductal papillary mucinous neoplasm

BACKGROUND

IPMNs are cystic pancreatic lesions with variable malignant potential. Thrombospondin-2 (THBS2)-an endogenous, anti-angiogenic matrix glycoprotein-may modulate tumor progression. We hypothesized that circulating levels of THBS2 could aid in preoperative prediction of malignant IPMN.

METHODS

Preoperative serum/plasma samples were procured from patients undergoing surgery. Circulating levels of THBS2 were measured (enzyme-linked immunosorbent assay) and compared to surgical pathology IPMN dysplastic grade.

RESULTS

164 patients underwent THBS2 testing (100 Low/Moderate-IPMN; 64 High-Grade/Invasive-IPMN). Circulating THBS2 (mean ± SD) was greater in High-Grade/Invasive-IPMN than Low/Moderate-grade IPMN (26.6 ± 12.7 ng/mL vs. 20.4 ± 8.2 ng/mL; P < 0.001). THBS2 (AUC = 0.65) out-performed CA19-9 (n = 144; AUC = 0.59) in predicting IPMN grade. The combination of THBS2, CA19-9, radiographic main-duct involvement, main-duct diameter, age, sex, and BMI (AUC 0.82; n = 137) provided a good prediction model for IPMN grade.

CONCLUSION

Circulating THBS2 is correlated with IPMN dysplasia grade. THBS2 alone did not strongly predict IPMN grade but rather strengthened prediction models for High-Grade/Invasive IPMN when combined with other clinical/biomarker data.

Pancreatic Cancer Cell Fraction Estimation in a DNA Sample

OBJECTIVE

Pancreatic cancers are characterized by dense stroma. To estimate the degree of interference by coexisting noncancer cells in molecular analyses, we aimed to develop a DNA methylation marker that assesses a cancer cell fraction in DNA samples.

METHODS

The microarray data of 22 pancreatic cancer tissues from the The Cancer Genome Atlas database and 9 noncancer tissues were used for genome-wide screening. Thirty-one surgical tumor samples (10 intraductal papillary mucinous neoplasms [IPMNs] and 21 pancreatic cancers), 4 normal, and 26 nontumor samples were used for validation. Gene-specific methylation analysis was conducted by bisulfite pyrosequencing.

RESULTS

Genome-wide screening isolated SIM1, MIR129-2, NR1I2, and HOXB-AS4, as specifically methylated in pancreatic cancer cells. Bisulfite pyrosequencing validated that one or more of three genes (SIM1, MIR129-2, and NR1I2) were methylated in 22 (71.0%) tumor samples (8 IPMNs and 14 cancers), and all showed low levels of methylation in 26 (86.7%) normal and nontumor samples. Therefore, the three genes collectively constituted one marker for a pancreatic cancer cell fraction. The cancer cell fraction estimated by the marker was highly correlated with that estimated using the KRAS mutant allele frequency (R = 0.79).

CONCLUSION

The DNA methylation marker is useful to estimate the pancreatic cancer cell fraction in DNA samples.

Diagnosis of intraductal papillary mucinous neoplasm using endoscopic ultrasound guided microbiopsies: A case report

Pancreatic cysts are increasingly diagnosed due to expanding use of cross-sectional imaging, but current diagnostic modalities have limited diagnostic accuracy. Recently, a novel through-the-needle microbiopsy forceps has become available, offering the possibility of obtaining cyst-wall biopsies. We present a case of 41-year-old male with chronic pancreatitis and a 2-cm pancreatic cyst, initially considered a pseudocyst. Subsequently, endoscopic ultrasound guided microbiopsies were successfully obtained, which surprisingly revealed an intraductal papillary mucinous neoplasm of mixed subtype with low grade dysplasia. In conclusion, obtaining biopsies from the wall of the pancreatic cystic lesions with this novel instrument is feasible and, as demonstrated in this case, can possibly alter the clinical outcome. Microbiopsies offered enough cellular material, allowing supplemental gene mutation analysis, which combined with other modalities could lead to a more individual approach when treating pancreatic cysts. However, prospective studies are warranted before routine clinical implementation.

New horizons in the endoscopic ultrasonography-based diagnosis of pancreatic cystic lesions

Pancreatic cystic lesions (PCLs) are increasingly being identified because of the widespread use of high-resolution abdominal imaging. These cysts encompass a spectrum from malignant disease to benign lesions, and therefore, accurate diagnosis is crucial to determine the best management strategy, either surgical resection or surveillance. However, the current standard of diagnosis is not accurate enough due to limitations of imaging and tissue sampling techniques, which entail the risk of unnecessary burdensome surgery for benign lesions or missed opportunities of prophylactic surgery for potentially malignant PCLs. In the last decade, endoscopic innovations based on endoscopic ultrasonography (EUS) imaging have emerged, aiming to overcome the present limitations. These new EUS-based technologies are contrast harmonic EUS, needle-based confocal endomicroscopy, through-the-needle cystoscopy and through-the needle intracystic biopsy. Here, we present a comprehensive and critical review of these emerging endoscopic tools for the diagnosis of PCLs, with a special emphasis on feasibility, safety and diagnostic performance.

Radiological Workup of Cystic Neoplasms of the Pancreas

Pancreatic cystic lesions are being detected with increasing frequency because of increased use and improved quality of cross-sectional imaging techniques. Pancreatic cystic lesions encompass non-neoplastic lesions (such as pancreatitis-related collections) and neoplastic tumors. Common cystic pancreatic neoplasms include serous cystadenomas, mucinous cystic neoplasms, intraductal papillary mucinous neoplasms, and solid pseudopapillary tumors. These cystic pancreatic neoplasms may have typical morphology, but at times show overlapping imaging features on cross-sectional examinations. This article reviews the classical and atypical imaging features of commonly encountered cystic pancreatic neoplasms and presents the limitations of current cross-sectional imaging techniques in accurately classifying pancreatic cystic lesions.

Cyst Fluid Biomarkers - Diagnosis and Prediction of Malignancy for Cystic Lesions of the Pancreas

Pancreatic cysts are common, and are identified in 2-13% of individuals undergoing cross-sectional imaging. Intraductal papillary mucinous neoplasms (IPMNs) and mucinous cystic neoplasms (MCNs) are pancreatic cysts which are precursors to pancreatic adenocarcinoma. Currently available tools are imperfect at differentiating IPMNs and MCNs from other, benign types of pancreatic cysts. The role of molecular markers in the evaluation of pancreatic cysts and the identification of cysts with high-grade dysplasia or invasive adenocarcinoma is reviewed.

The Role of Endoscopic Ultrasound in the Diagnosis of Cystic Lesions of the Pancreas

A precise diagnosis of the nature of pancreatic cystic neoplasm (PCN) is crucial since it determines the patients in need of rapid surgical resection as well as those who can be followed up, and, accordingly, the frequency and modalities of surveillance. Endoscopic ultrasound (EUS) and especially fine needle aspiration (FNA) are invasive methods, with specific adverse events occurring in 2.7-5%. Thus, they should only be used as a third-line tool in the absence of characteristic radiographic features on computed tomography (CT) scan and magnetic resonance imaging (MRI). The most difficult aspects of differential diagnosis are: intraductal papillary mucinous neoplasm (IPMN) versus chronic pancreatitis; unifocal IPMN versus serous cystic neoplasm (SCN); macrocystic SCN versus mucinous cystic neoplasm (MCN); cystic neuroendocrine tumors versus MCN; solid serous cystadenoma versus neuroendocrine tumors versus small solid pseudopapillary tumors; pseudocyst versus MCN; low-grade, high-grade, or invasive IPMN. When classical radiological and EUS features are not conclusive, EUS-FNA may be helpful by analyzing cytological, chemical, and/or molecular data. The addition of EUS-FNA to CT scan and MRI increased the overall accuracy for diagnosing PCN by 36 and 54%, respectively. Analysis of molecular markers in pancreatic cyst fluid might increase the limited accuracy of EUS-FNA by using cytology and chemical and/or tumor marker analysis alone. Current evidence suggests that contrast-enhanced EUS (CH-EUS) is highly accurate for distinguishing non-neoplastic cysts from neoplastic cysts. CH-EUS might also be useful for distinguishing mural epithelial nodules from mucinous clots. Needle-based confocal laser endomicroscopy (nCLE) images a target tissue at a subcellular level of resolution, providing real-time in-vivo optical biopsy. nCLE is feasible during EUS-FNA and allows in-vivo diagnosis of PCN with high accuracy. In conclusion, EUS is a third-line tool in the diagnosis of PCN. Clinical context as well as careful evaluation of CT scan and magnetic resonance cholangiopancreatography images by specialized radiologists are crucial in the diagnosis process. Nowadays it is inconceivable to skip these steps.

Clinicopathological and prognostic significance of MUC13 and AGR2 expression in intraductal papillary mucinous neoplasms of the pancreas

BACKGROUND

Intraductal papillary mucinous neoplasm (IPMN) of the pancreas is a primary pancreatic ductal epithelial neoplasm with the potential to develop into an invasive adenocarcinoma. This study aimed to investigate the clinicopathologic and prognostic significance of four potential biomarkers for the preoperative evaluation of patients with IPMN.

MATERIALS AND METHODS

Clinicopathologic materials from 104 patients with IPMN who underwent surgical resection at Jichi Medical University Hospital were analyzed. IPMNs (110 lesions in total) were histologically classified into low-grade IPMN (Group 1; n = 68), high-grade IPMN (Group 2; n = 16), or IPMN with an associated invasive carcinoma (Group 3; n = 26). We evaluated the immunohistochemical expression of MUC13, AGR2, FUT8, and FXYD3, which were previously reported to be overexpressed in pancreatic ductal adenocarcinoma.

RESULTS

The expression of MUC13 was more common in Group 3 compared with groups 1 and 2 (p < 0.001) and was associated with poor prognosis (p = 0.004). The expression of MUC13 was not associated with age, sex, tumor location, histological subtype, lymphatic or vascular invasion, or neural invasion. In most cases of IPMN, the loss of expression of AGR2 appeared to show an association with tumor recurrence and poorly differentiated histology of invasive carcinoma; however, this association was not statistically significant. The expressions of FUT8 and FXYD3were not associated with the clinicopathological features of IPMNs.

CONCLUSIONS

The results suggest that MUC13 overexpression and loss of expression of AGR2 may predict the progression of IPMN and an unfavorable prognosis in patients with IPMN.

Multifocal cysts and incidence of pancreatic cancer concomitant with intraductal papillary mucinous neoplasm

OBJECTIVES

The present study was conducted in order to elucidate the relationship between the number of cyst-existing regions and incidence of pancreatic ductal adenocarcinoma (PDAC) concomitant with intraductal papillary mucinous neoplasm (IPMN), which currently remains unclear.

METHODS

Subjects comprised 141 patients undergoing resection for IPMN (Non-invasive IPMN (IPMN with low-to high-grade dysplasia): N = 94, invasive IPMN: N = 31, and PDAC concomitant with IPMN: N = 16) between November 2000 and February 2017. A logistic regression analysis was performed to assess the relationship between the number of cyst-existing regions (one region/two or more regions) and incidence of PDAC concomitant with IPMN, adjusted by clinical characteristics. Cyst-existing regions were defined by the number of anatomical parts of the pancreas: the head/body/tail of the pancreas.

RESULTS

Multiple cyst-existing regions (two or more regions) correlated with the incidence of PDAC concomitant with IPMN (PDAC concomitant with IPMN in one region vs. two or more regions: 3/66 vs. 13/75, multivariable odds ratio [OR] = 4.11, 95% confidence interval [CI] = 1.22 to 18.8, P = 0.02). In contrast, multiple cyst-existing regions did not correlate with the incidence of IPMN (invasive IPMN in one region vs. two or more regions: 13/66 vs. 18/75, OR = 1.19, 95% CI = 0.52 to 2.76, P = 0.67).

CONCLUSIONS

Multifocal cysts correlated with the incidence of PDAC concomitant with IPMN, and may be a high-risk factor for PDAC concomitant with IPMN.

Intraductal Papillary Mucinous Neoplasms of The Pancreas: A Nationwide Registry-Based Study

BACKGROUND AND AIMS:

To investigate the paraclinical and pathological features of surgically resected intraductal papillary mucinous neoplasms in Sweden.

MATERIALS AND METHODS:

A review of prospectively collected data on patients undergoing pancreatic resection for a histopathologically verified intraductal papillary mucinous neoplasm between 2010 and 2016 was performed using the Swedish National Registry for Pancreatic and Periampullary Cancer.

RESULTS:

A total of 3038 pancreatic resections were performed during the study period, of which 251 (8.3%) were due to intraductal papillary mucinous neoplasms. The intraductal papillary mucinous neoplasm cases comprised 227 noninvasive and 24 invasive lesions. There was an annual increase in the number of resected intraductal papillary mucinous neoplasms, from 13 in 2010 to 56 in 2016, and an increase in the proportion of intraductal papillary mucinous neoplasm to the total number of pancreatic resections (4.7%-11%). Biliary obstruction was the only independent predictor of invasive disease, with odds ratio 3.106 (p = 0.030). There was no difference in survival between low-, intermediate-, and high-grade dysplastic lesions (p = 0.417). However, once invasive, the prognosis was severely impacted (p < 0.001). Three-year survival was 90% for noninvasive intraductal papillary mucinous neoplasm and 39% for invasive intraductal papillary mucinous neoplasm. Survival was better in lymph node negative invasive intraductal papillary mucinous neoplasm (p = 0.021), but still dismal compared to noninvasive lesions (p < 0.001).

CONCLUSION:

The number of surgically resected intraductal papillary mucinous neoplasms is increasing in Sweden. Biliary obstruction is associated with invasive disease. Low-to-high-grade dysplastic intraductal papillary mucinous neoplasm has an excellent prognosis, while invasive intraductal papillary mucinous neoplasm has a poor survival rate.

Evaluation of the International Consensus Guidelines for the Surgical Resection of Intraductal Papillary Mucinous Neoplasms

BACKGROUND

International consensus guidelines for intraductal papillary mucinous neoplasms (IPMNs) were revised in 2012.

AIMS

We aimed to evaluate the clinical utility of each predictor in the 2006 and 2012 guidelines and validate the diagnostic value and surgical indications.

METHODS

Forty-two patients with surgically resected IPMNs were included. Each predictor was applied to evaluate its diagnostic value.

RESULTS

The 2012 guidelines had greater accuracy for invasive carcinoma than the 2006 guidelines (64.3 vs. 31.0%). Moreover, the accuracy for high-grade dysplasia was also increased (48.6 vs. 77.1%). When the main pancreatic duct (MPD) size ≥8 mm was substituted for MPD size ≥10 mm in the 2012 guidelines, the accuracy for high-grade dysplasia was 80.0%.

CONCLUSIONS

The 2012 guidelines exhibited increased diagnostic accuracy for invasive IPMN. It is important to consider surgical resection prior to invasive carcinoma, and high-risk stigmata might be a useful diagnostic criterion. Furthermore, MPD size ≥8 mm may be predictive of high-grade dysplasia.

The curious case of Gαs gain-of-function in neoplasia

BACKGROUND

Mutations activating the α subunit of heterotrimeric Gs protein are associated with a number of highly specific pathological molecular phenotypes. One of the best characterized is the McCune Albright syndrome. The disease presents with an increased incidence of neoplasias in specific tissues.

MAIN BODY

A similar repertoire of neoplasms can develop whether mutations occur spontaneously in somatic tissues during fetal development or after birth. Glands are the most "permissive" tissues, recently found to include the entire gastrointestinal tract. High frequency of activating Gαs mutations is associated with precise diagnoses (e.g., IPMN, Pyloric gland adenoma, pituitary toxic adenoma). Typically, most neoplastic lesions, from thyroid to pancreas, remain well differentiated but may be a precursor to aggressive cancer.

CONCLUSIONS

Here we propose the possibility that gain-of-function mutations of Gαs interfere with signals in the microenvironment of permissive tissues and lead to a transversal neoplastic phenotype.

Analysis of Pancreatic Cyst Fluid

Pancreatic cysts are extremely common, and are identified in between 2% to 13% on abdominal imaging studies. Most pancreatic cysts are pseudocysts, serous cystic neoplasms, mucinous cystic neoplasms, or intraductal papillary mucinous neoplasms. The management of pancreatic cysts depends on whether a cyst is benign, has malignant potential, or harbors high-grade dysplasia or invasive carcinoma. The diagnosis of pancreatic cysts, and assessment of risk of malignant transformation, incorporates clinical history, computed tomography (CT), magnetic resonance imaging (MRI), endoscopic ultrasound, and fine-needle aspiration of cyst fluid. This article reviews the cyst fluid markers that are currently used, as well as promising markers under development.

Significance of microcystic, elongated, and fragmented glandular-like features in intraductal papillary mucinous neoplasm of the pancreas

Microcystic, elongated, and fragmented (MELF) glandular features are associated with epithelial-mesenchymal transition, invasion, and progression in endometrioid adenocarcinoma of the uterus. Similar histological features are also observed at the periphery of pancreatic intraductal papillary mucinous neoplasms (IPMNs). However, the clinicopathological significance of MELF-like features-particularly whether they represent regenerative or truly neoplastic conditions-in IPMNs remains unclear. We assessed a total of 152 surgically resected IPMNs. Fifty cases exhibited MELF-like features, including 26 cases of IPMNs with accompanying adenocarcinomas and 24 cases of IPMNs without accompanying adenocarcinomas. MELF-like features were more frequently observed in IPMN cases with accompanying adenocarcinomas, larger tumors, main-duct type, and non-gastric histologic subtype. A positive correlation between the presence of MELF-like features and high-grade dysplasia was observed in IPMNs without accompanying adenocarcinomas. Moreover, DPC4 loss and p53 overexpression in MELF-like glands were more commonly observed in IPMNs with high-grade dysplasia. IPMN patients with MELF-like features had worse overall and disease-specific survival by univariate analyses. Our observations suggest that MELF-like features in some IPMNs with high-grade dysplasia could be related to stromal invasion. Hence, when MELF-like features are observed in IPMNs, pathologists should carefully evaluate the results of microscopic examinations to identify the invasive components; and, immunohistochemical staining for DPC4 and p53 could help clarify its clinicopathological significance.

An elevated expression of serum exosomal microRNA-191, - 21, -451a of pancreatic neoplasm is considered to be efficient diagnostic marker

BACKGROUND

Pancreatic cancer is associated with an extremely poor prognosis, so new biomarkers that can detect the initial stages are urgently needed. The significance of serum microRNA (miR) levels in pancreatic neoplasm such as pancreatic cancer and intraductal papillary mucinous neoplasm (IPMN) diagnosis remains unclear. We herein evaluated the usefulness of miRs enclosed in serum exosomes (ExmiRs) as diagnostic markers.

METHODS

The ExmiRs from patients with pancreatic cancer (n = 32) or IPMN (n = 29), and patients without neoplasms (controls; n = 22) were enriched using ExoQuick-TC™. The expression of ExmiRs was evaluated using a next-generation sequencing analysis, and the selected three miRs through this analysis were confirmed by a quantitative real-time polymerase chain reaction.

RESULTS

The expression of ExmiR-191, ExmiR-21 and ExmiR-451a was significantly up-regulated in patients with pancreatic cancer and IPMN compared to the controls (p < 0.05). A receiver operating characteristic curve analysis showed that the area under the curve and the diagnostic accuracy of ExmiRs were 5-20% superior to those of three serum bulky circulating miRs (e.g.; ExmiR-21: AUC 0.826, accuracy 80.8%. Circulating miR-21: AUC 0.653, accuracy 62.3%). In addition, high ExmiR-451a was associated with mural nodules in IPMN (p = 0.010), and high ExmiR-21 was identified as a candidate prognostic factor for the overall survival (p = 0.011, HR 4.071, median OS of high-ExmiR-21: 344 days, median OS of low-ExmiR-21: 846 days) and chemo-resistant markers (p = 0.022).

CONCLUSIONS

The level of three ExmiRs can thus serve as early diagnostic and progression markers of pancreatic cancer and IPMN, and considered more useful markers than the circulating miRs (limited to these three miRs).

Multicenter study of early pancreatic cancer in Japan

BACKGROUND/OBJECTIVES

The diagnosis of early-stage pancreatic ductal adenocarcinoma (PDAC) is still challenging. We conducted a multicenter study to clarify the clinical features of early-stage PDAC in Japan.

METHODS

We collected patients with stage 0 and stage I PDAC according to the sixth edition of the Japanese Classification of Pancreatic Carcinoma. We retrospectively analyzed the clinical profiles including opportunities for medical examination, imaging modalities and findings, methods of cytological diagnosis, and prognosis according to the stages at diagnosis.

RESULTS

Two hundred cases with Stage 0 and stage I PDAC were reported from 14 institutions, which accounted for approximately 0.7% and 3% of all PDAC cases, respectively. Overall, 20% of the early-stage PDAC cases were symptomatic. Indirect imaging findings such as dilatation of the main pancreatic duct were useful to detect early-stage PDAC. In particular, local fatty changes may be specific to early-stage PDAC. For preoperative pathologic diagnosis, cytology during endoscopic retrograde cholangiopancreatography was more commonly applied than endoscopic ultrasound fine-needle aspiration. Although the overall prognosis was favorable, new PDAC lesions developed in the remnant pancreas in 11.5% cases.

CONCLUSIONS

This multicenter study revealed several key points concerning the diagnosis and management of early-stage PDAC, including screening of asymptomatic cases, importance of indirect imaging findings, application of cytology during endoscopic retrograde cholangiopancreatography, and the risk of carcinogenesis in the remnant pancreas.

Prevalence and outcomes of pancreatic cystic neoplasms in liver transplant recipients

AIM

To determine the prevalence, characteristics and clinical course of pancreatic cystic neoplasms (PCNs) in liver transplantation (LT) recipients.

METHODS

We retrospectively studied consecutive patients who underwent LT between January 1998 to April 2016. Clinical and laboratory data were obtained from patient medical records. Imaging findings on computed tomography and magnetic resonance cholangiopancreatography were reviewed by two radiologists.

RESULTS

During the study period, 872 patients underwent cadaveric LT. Pancreatic cysts were identified in 53/872 (6.1%) and 31/53 (58.5%) were PCNs [28 intraductal papillary mucinous neoplasm (IPMN), 2 mucinous cystic neoplasm (MCN), 1 serous cystadenoma]. Patients with PCNs exhibited less male predominance (55% vs 73%, P = 0.03) compared to patients without pancreatic cysts. Thirteen patients (42%) were diagnosed with PCN pre-LT while 18 patients (58%) developed PCN post-LT. The median size of PCNs was 13mm [interquartile range (IQR) 10-20 mm]. All IPMNs were side-branch type. Most PCNs were found in the head and body of pancreas (37% each), followed by the tail (25%). Five patients underwent further evaluation with endoscopic ultrasound. Progress imaging was performed on 81% of patients. PCNs remained stable in size and number in all but 2 patients. During a median follow up of 39 mo (IQR 26-58 mo), the 2 (6%) patients with MCN underwent pancreatectomy. No PCN patient developed pancreatic adenocarcinoma, while 5 died from illnesses unrelated to the PCN. Among patients without PCN, 1/841 (0.1%) developed pancreatic adenocarcinoma.

CONCLUSION

The prevalence of PCNs in LT recipients was similar to the general population (3.6%, 31/872). Side-branch IPMNs do not appear to have accelerated malignant potential in post-LT patients, indicating the current surveillance guidelines are applicable to this group.

Association between the Risk Factors for Pancreatic Ductal Adenocarcinoma and Those for Malignant Intraductal Papillary Mucinous Neoplasm

BACKGROUND AND AIMS

Risk factors for pancreatic ductal adenocarcinoma (PDAC) include diabetes mellitus, chronic pancreatitis, obesity, a family history of pancreatic cancer, and a history of smoking or alcohol consumption. The aim of this study was to evaluate the association between risk factors for PDAC and malignant intraductal papillary mucinous neoplasm (IPMN).

METHODS

The study included 134 consecutive patients with IPMN who underwent surgical resection at Kindai University Hospital between April 2009 and March 2015. Data on the presence or absence of mural nodules (MNs) and risk factors for PDAC were evaluated. Multivariable logistic regression analysis was performed with malignant IPMN as the outcome variable and MNs and risk factors for PDAC as explanatory variables.

RESULTS

The odds ratio of malignant IPMN to MNs was 3.88 (95% confidence interval [CI] 1.53-9.84; p = 0.004), whereas that of malignant IPMN to smoking history was 1.66 (95% CI 0.74-3.71; p = 0.22). When the presence of MNs was considered as a predictive factor for malignancy, the sensitivity and specificity were 88.5 and 32.1%, respectively, whereas when the presence of both smoking history and MNs was considered, the specificity improved to 73.2%, with a decrease in sensitivity to 42.3%.

CONCLUSIONS

The presence of both a smoking history and MNs was a valuable predictive factor for malignant IPMN with high specificity. A smoking history should be considered before surgical resection in addition to the presence of MNs.

A Social Program for the Early Detection of Pancreatic Cancer: The Kishiwada Katsuragi Project

OBJECTIVES

The early-stage pancreatic cancer (e-PC; stage I/II) detection rate is quite low at approximately 25%. The aim of this study was to evaluate the feasibility of a social program (the Kishiwada Katsuragi project) wherein our hospital, which specializes in PC, and primary care medical offices (PMOs) used clinical findings to detect e-PC.

METHODS

Patients with a score of ≥2 points on clinical findings were enrolled: symptoms of abdominal pain/back pain (1 point), new-onset diabetes (1 point), high amylase (AMY) and/or pancreaitc AMY (P-AMY) (1 point), high carbohydrate antigen 19-9 (1 point), and ultrasonography (US) findings including direct (e.g., a solid pancreatic tumor) and/or indirect findings (e.g., dilatation of a pancreatic diameter of ≥2.5 mm and/or cystic lesions) (2 points) were evaluated using the protocol for social programs.

RESULTS

Between November 2014 and December 2016, 244 patients were enrolled by 41 PMOs as cooperative facilities, and 15 e-PC cases (53.6%) of the 28 PC patients were detected. The mean clinical finding score of the e-PC group (3.13 ± 1.9) was significantly higher than that of the overall non-PC group (2.1 ± 0.4) (p < 0.05). "High AMY/P-AMY" and "symptoms" were significantly more frequent in the e-PC group than in the non-PC group (p < 0.05). Although the sensitivity of direct findings by US was 40.0%, that of indirect-findings was 93.3% in the e-PC group. Nine and 6 of the 15 patients with e-PC were enrolled via general internal medicine offices (GIMs) and other PMOs without GIMs (general surgery, n = 3; urology, n = 2; otolaryngology, n = 1).

CONCLUSION

This social program with collaborations between medical centers that specialize in PC and PMOs used clinical findings, suggesting that not only GIMs but also other PMOs and indirect findings by US may play an important role in improving the e-PC detection rate.

Chronic Pancreatitis Finding by Endoscopic Ultrasonography in the Pancreatic Parenchyma of Intraductal Papillary Mucinous Neoplasms Is Associated with Invasive Intraductal Papillary Mucinous Carcinoma

BACKGROUND/OBJECTIVES

The recent guideline for intraductal papillary mucinous neoplasms (IPMNs) focuses on morphological features of the lesion as signs of malignant transformation, but ignores the background pancreatic parenchyma, including features of chronic pancreatitis (CP), which is a risk factor for pancreatic malignancies. Endoscopic ultrasonography frequently reveals evidence of CP (EUS-CP findings) in the background pancreatic parenchyma of patients with IPMNs. Therefore, we investigated whether background EUS-CP findings were associated with malignant IPMN.

METHODS

The clinical data of 69 consecutive patients with IPMNs who underwent preoperative EUS and surgical resection between April 2010 and October 2014 were collected prospectively. The association of EUS-CP findings (total number of EUS-CP findings; 0 vs. ≥1) with invasive IPMN was examined. The association of EUS-CP findings with pathological changes of the background pancreatic parenchyma (atrophy/inflammation/fibrosis) was also examined.

RESULTS

Among patients with EUS-CP findings, invasive intraductal papillary mucinous carcinoma (IPMC) was significantly more frequent than among patients without EUS-CP findings (42.5% [17/40] vs. 3.4% [1/29], p = 0.0002). In addition, patients with EUS-CP findings had higher grades of pancreatic atrophy and inflammation than patients without EUS-CP findings (atrophy: 72.5% [29/40] vs. 34.5% [10/29], p = 0.003; inflammation: 45.0% [18/40] vs. 20.7% [6/29], p = 0.04).

CONCLUSIONS

In IPMN patients, detection of EUS-CP findings in the background pancreatic parenchyma was associated with a higher prevalence of invasive IPMC. Accordingly, EUS examination should not only assess the morphological features of the lesion itself, but also EUS-CP findings in the background parenchyma.