Pancreatic juice cytology in the diagnosis of intraductal papillary mucinous neoplasm of the pancreas: significance of sampling by peroral pancreatoscopy

Is preoperative pancreatic juice cytology useful for determining therapeutic strategies for patients with intraductal papillary mucinous neoplasm of the pancreas?

BACKGROUND

We compared the results of preoperative pancreatic juice cytology (PJC) and final pathological diagnosis after resection in patients who underwent resection of intraductal papillary mucinous neoplasm (IPMN) of the pancreas to determine whether preoperative PJC can help determine therapeutic strategies.

METHODS

Of 1130 patients who underwent surgical resection IPMN at 11 Japanese tertiary institutions, the study included 852 patients who underwent preoperative PJC guided by endoscopic retrograde cholangiopancreatography (ERCP).

RESULTS

The accuracy of preoperative PJC for differentiation between cancerous and noncancerous lesions were 55% for IPMN overall; 59% for the branch duct type; 49% for the main pancreatic duct type; 53% for the mixed type, respectively. On classifying IPMN according to the diameters of the mural nodule (MN) and main pancreatic duct (MPD), the corresponding values for diagnostic performance were 40% for type 1 (MN ≥5 mm and MPD ≥ 10 mm); 46% for type 2 (MN ≥5 mm and MPD < 10 mm); 61% for type 3 (MN < 5 mm and MPD ≥ 10 mm); 72% for type 4 (MN < 5 mm and MPD < 10 mm), respectively.

CONCLUSIONS

PJC in IPMN is not a recommended examination because of its low overall sensitivity and no significant difference in diagnostic performance by type, location, or subclassification. Although the sensitivity is low, the positive predictive value is high, so we suggest that pancreatic juice cytology be performed only in cases where the patient is not sure about surgery.

Usefulness of Contrast-Enhanced Harmonic Endoscopic Ultrasonography for Diagnosis of Malignancy in Intraductal Papillary Mucinous Neoplasm

Intraductal papillary mucinous neoplasms (IPMNs) have a wide pathologic spectrum and it can be difficult to diagnose malignancy, including pathological grade. The aim of this study was to evaluate contrast-enhanced harmonic endoscopic ultrasonography (CH-EUS) for the diagnosis of malignant IPMN and IPMN-associated invasive carcinoma (invasive IPMC). From 5009 patients diagnosed with IPMN at Wakayama medical university between December 2009 and December 2021, 115 patients who underwent contrast-enhanced computed tomography (CE-CT), conventional EUS, CH-EUS, and surgical resection were enrolled. The detection of mural lesions was compared with pathological findings. Malignant IPMN and invasive IPMC were also assessed according to mural lesion size and vascularity on CH-EUS. CH-EUS and conventional EUS showed significantly higher accuracy than CE-CT in the detection of mural nodules (92%, 83%, and 72%, respectively) and diagnosis of malignant IPMN (75%, 73%, and 63%, respectively). An early wash-out pattern on CH-EUS was observed in significantly more patients with invasive IPMC than in those with low-, intermediate-, or high-grade dysplasia. When compared with CE-CT, CH-EUS was significantly more accurate for detecting mural nodules and more useful for diagnosing malignant IPMN. The vascular pattern on CH-EUS was also useful for diagnosing invasive IPMC.

The role of pancreatoscopy in the diagnostic work-up of intraductal papillary mucinous neoplasms: a systematic review and meta-analysis

BACKGROUND

Confirming the diagnosis, invasiveness, and disease extent of intraductal papillary mucinous neoplasms (IPMNs) of the pancreas is challenging. The aim of this study was to summarize the literature on the efficacy and safety of peroral pancreatoscopy (POP) in the diagnosis of IPMN, including the impact of pre- and intraoperative POP on the management of IPMN.

METHODS

The EMBASE, Medline Ovid, Web of Science, Cochrane CENTRAL, and Google Scholar databases were systematically searched for articles. Eligible articles investigated cohorts of patients who underwent POP for (suspected) IPMN.

RESULTS

25 articles were identified and included in this review; with 22 of these reporting on the diagnostic yield of POP in IPMN and 11 reporting on the effect of pre- or intraoperative POP on clinical decision-making. Cannulation and observation rates, and overall diagnostic accuracy were high across all studies. Frequently reported visual characteristics of IPMN were intraductal fish-egg-like lesions, hypervascularity, and granular mucosa. Overall, the adverse event rate was 12 %, primarily consisting of post-endoscopic retrograde cholangiopancreatography pancreatitis, with a pooled rate of 10 %, mostly of mild severity. Regarding the impact of POP on clinical decision-making, POP findings altered the surgical approach in 13 %-62 % of patients.

CONCLUSION

POP is technically successful in the vast majority of patients with (suspected) IPMN, has a consistently high diagnostic accuracy, but an adverse event rate of 12 %. Data on intraoperative pancreatoscopy are scarce, but small studies suggest its use can alter surgical management. Future studies are needed to better define the role of POP in the diagnostic work-up of IPMN.

Single-operator peroral pancreatoscopy in the preoperative diagnostics of suspected main duct intraductal papillary mucinous neoplasms: efficacy and novel insights on complications

Background

Distinguishing intraductal papillary mucinous neoplasms (IPMNs) from other pancreatic cystic lesions is essential since IPMNs carry the risk of becoming malignant. Differentiating the main pancreatic duct involving IPMNs (MD-IPMNs) through conventional imaging is deficient. Single-operator peroral pancreatoscopy (SOPP) represents a promising method offering additional information on suspected lesions in the pancreatic main duct (MD). We aimed to determine the role of SOPP in the preoperative diagnostics of suspected MD-IPMNs and identify factors contributing to SOPP-related complications.

Materials and Methods

In this primarily retrospective study, SOPPs were performed at three high-volume centers on suspected MD-IPMNs. Primary outcome was the clinical impact of SOPP to subsequent patient care. Additionally, we documented post-SOPP complications and analyzed several assumed patient- and procedure-related risk factors.

Results

One hundred and one (101) SOPPs were performed. Subsequent clinical management was affected due to the findings in 86 (85%) cases. Surgery was planned for 29 (29%) patients. A condition other than IPMN explaining MD dilatation was found in 28 (28%) cases. In 35 (35%) cases, follow-up with MRI was continued. Post-SOPP pancreatitis occurred in 20 (20%) patients and one of them was fatal. A decrease in odds of post-SOPP pancreatitis was seen as the MD diameter increases (OR 0.714 for 1.0 mm increase in MD diameter, CI 95% 0.514–0.993, p = 0.045). Furthermore, a correlation between lower MD diameter values and higher severity post-SOPP pancreatitis was seen (T_JT = 599, SE = 116.6, z = − 2.31; p = 0.020). History of pancreatitis after endoscopic retrograde cholangiopancreatography was a confirmed risk factor for post-SOPP pancreatitis. Conclusions between complications and other risk factors could not be drawn.

Conclusion

SOPP aids clinical decision-making in suspected MD-IPMNs. Risk for post-SOPP pancreatitis is not negligible compared to non-invasive imaging methods. The risk for pancreatitis decreases as the diameter of the MD increases.

Predictors of malignancy in main duct intraductal papillary mucinous neoplasm of the pancreas

BACKGROUND AND AIMS

The International Consensus Guidelines updated in 2017 recommended surgery to all main duct intraductal papillary mucinous neoplasms (MD-IPMNs) with the main pancreatic duct (MPD) of 10 mm or more and those with mural nodules regardless of size. The aim of the present study was to identify predictors of malignancy in MD-IPMN among preoperative factors including MPD and mural nodule size.

METHODS

Twenty-six benign MD-IPMNs (7 resected and 19 nonresected) and 32 malignant MD-IPMNs (31 resected and 1 nonresected) were included in the study. MRCP, CT, EUS, and cytology were performed using pancreatic juice collected by endoscopic retrograde pancrestography (ERP). Resected IPMNs were classified as benign or malignant by histologic examination and nonresected MD-IPMNs by imaging, cytology, and observation. Cutoff values of candidate parameters were determined by receiver operating characteristic curves. Univariate and multivariate analyses by regression model were performed.

RESULTS

MPD and mural nodule size and cytology results differed significantly between benign and malignant groups. Cutoff values of MPD and mural nodule sizes were 15 mm and 10 mm with areas under the curve of .66 and .86, respectively. Mural nodules of 10 mm or more (odds ratio, 8.32; 95% confidence interval, 1.13-61.2; P = .038) and positive cytology (odds ratio, 42.5; 95% confidence interval, 4.10-439; P = .002) were shown to be independent predictors of malignancy by multivariate analysis. When MD-IPMNs with either predictor were diagnosed to be malignant, sensitivities, specificities, and overall accuracy for malignancy were 94%, 85%, and 90%, respectively.

CONCLUSIONS

Mural nodules of 10 mm or more and positive cytology were independent predictors of malignancy in MD-IPMN.

Cystic pancreatic lesions, the endless dilemma

Cystic pancreatic lesions involve a wide variety of pathological entities that include neoplastic and non-neoplastic lesions. The proper diagnosis, differentiation, and staging of these cystic lesions are considered a crucial issue in planning further management. There are great challenges for their diagnostic models. In our time, new emerging methods for this diagnosis have been discovered. Endoscopic ultrasonography-guided fine-needle aspiration cytology with chemical and molecular analysis of cyst fluid and EUS-guided fine needle-based confocal laser endomicroscopy, through the needle microforceps biopsy, and single-operator cholangioscopy/pancreatoscopy are promising methods that have been used in the diagnosis of cystic pancreatic lesions. Hereby we discuss the diagnosis of cystic pancreatic lesions and the benefits of various diagnostic models.

Intraductal papillary mucinous neoplasm of the pancreas: Cytomorphology, imaging, molecular profile, and prognosis

BACKGROUND

Intraductal papillary mucinous neoplasm (IPMN) constitutes up to 20% of all pancreatic resections, and has been increasing in recent years. Histomorphological findings of IPMN are well established; however, there are not many published papers regarding the cytological findings of IPMN on fine needle aspiration (FNA) specimens. We review the cytomorphological features, molecular profile, imaging findings, and prognosis of IPMN.

METHODS

The English literature was thoroughly searched with key phrases containing IPMN.

OBSERVATIONS

IPMN is a rare entity, affecting men and women equally and is usually diagnosed at the age of 60-70 years. The characteristic imaging features include a cystic lesion with associated dilatation of the main or branch pancreatic duct, and atrophy of surrounding pancreatic parenchyma. Cytomorphological features of IPMN include papillary fragments of mucinous epithelium in a background of abundant thick extracellular mucin, a hallmark feature. IPMNs should be evaluated for high-grade dysplasia, which manifests with nuclear atypia, nuclear moulding, prominent nucleoli, nuclear irregularity, and cellular crowding. Molecular profiling of IPMN along with carcinoembryonic antigen and amylase levels is useful in predicting malignancy or high-grade dysplasia arising in IPMN. Overall, the prognosis of IPMN is excellent except in those cases with high-grade dysplasia and malignant transformation. Postoperative surveillance is required for resected IPMNs.

CONCLUSION

IPMN requires a multidisciplinary approach for management. Cytomorphological findings of IPMN on FNA, in conjunction with tumour markers in pancreatic fluid cytology and imaging findings, are of paramount importance in clinical decision-making for IPMN.

Premalignant lesions of the extrahepatic biliary tract. A territory to be explored hand in hand with cholangioscopy

The biliary mucosa, both intrahepatic and extrahepatic, is lined by a single layer of columnar cells with oval nuclei near the base and a slightly eosinophilic cytoplasm. Although normal biliary ducts have no goblet cells, there are periductal mucous glands lined by mucus-producing cuboidal cells, with mucin from these glands draining to the lumen of bile ducts.

Value of repeated cytology for intraductal papillary mucinous neoplasms of the pancreas with high risk potential of malignancy: Is it a promising method for monitoring a malignant transformation?

OBJECTIVES

The efficacy of and indications for cytological reexamination to detect malignant changes in branch duct type intraductal papillary mucinous neoplasms (BD-IPMNs) have not been studied in detail. We conducted a retrospective study to evaluate the efficacy and indications of cytological reexamination by using pancreatic juice (repeated cytology) for BD-IPMNs.

METHODS

Forty-five patients who underwent repeated cytology after a diagnosis of benignancy by using initial cytology were recruited for this study.

RESULTS

Thirty-eight patients, excluding 7 patients with lack of surveillance period after the final cytology, were classified into Malignancy (n = 13) and Benignancy groups (n = 25) on the bases of the findings from resected specimens or changes in BD-IPMNs after repeated cytology. The sensitivity and specificity to detect malignant changes in BD-IPMNs by using repeated cytology were 62% and 100%, respectively. For the 12 patients with mural nodules (MNs) ≥ 5 mm (67% of them were malignant), the sensitivity was 50%, whereas, for the 26 patients without MNs ≥ 5 mm (19% of them were malignant), it was 80%. In addition, malignant changes in BD-IPMNs after initial cytology occurred in 62% of the patients with changes in the MNs and 27% of the patients with an increase in the cyst size.

CONCLUSION

Repeated cytology can play a role in the determination for surgery even after a diagnosis of benignancy by using initial cytology, especially for BD-IPMNs without MNs ≥5 mm. In addition, changes in the MNs or cyst size may be appropriate indications for repeated cytology.

Cytologic Analysis of Pancreatic Juice Increases Specificity of Detection of Malignant IPMN-A Systematic Review

BACKGROUND & AIMS

Intraductal papillary mucinous neoplasms (IPMNs) of the pancreas can progress to cancer. Biomarkers have been identified that were reported to increase the accuracy of identification of malignant lesions; we performed a systematic review of the accuracy of these markers.

METHODS

We performed a systematic review of published studies on biomarkers of malignant IPMNs by searching MEDLINE and Web of Science databases from January 2005 through December 2017. Our methods were developed based on the Meta-analysis Of Observational Studies in Epidemiology guidelines. Pooled sensitivity, specificity, receiver operating characteristic curves, and their respective areas under the curve (AUC) were calculated from groups of markers (cell-, protein-, or DNA-based) measured in samples collected before and after surgery. A hypothetical test model was developed to determine how to meaningfully amend the revised Fukuoka guidelines, focusing on increasing test specificity for patients with IPMNs that have worrisome features.

RESULTS

We collected data from 193 published studies, comprising 12,297 patients, that analyzed 7 preoperative and 21 postoperative markers of IPMNs. The 3 biomarkers that identified malignant IPMNs with the largest AUC values were pancreatic juice cytology (AUC, 0.84; sensitivity, 0.54; specificity, 0.91), serum protein carbohydrate antigen 19-9 (AUC, 0.81; sensitivity, 0.45; specificity, 0.90), and cyst fluid cytology (AUC, 0.82; sensitivity, 0.57; specificity, 0.84). A combination of cytologic and immunohistochemical analysis of MUC1 and MUC2 in pancreatic juice samples identified malignant IPMNs with the largest AUC and sensitivity values (AUC, 0.85; sensitivity, 0.85; specificity, 0.65). In a test model, inclusion of cytologic analysis of pancreatic juice in the guideline algorithm significantly increased the specificity of detection of malignant IPMNs.

CONCLUSIONS

In a systematic review, we found cytologic analysis of pancreatic juice to have the greatest effect in increasing the specificity of detection of malignant IPMNs. We propose addition of this test to the Fukuoka guidelines for assessment of patients with IPMNs with worrisome features.

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.

Pancreatoscopy: An update

Per-oral pancreatoscopy (POPS) is an endoscopic procedure to visualize the main pancreatic duct. POPS specifically has the advantage of direct visualization of the pancreatic duct, allowing tissue acquisition and directed therapies such as stones lithotripsy. The aim of this review is to analyze and summarize the literature around pancreatoscopy. Pancreatoscopy consists of the classic technique of the mother-baby method in which a mini-endoscope is passed through the accessory channel of the therapeutic duodenoscope. Pancreatoscopy has two primary indications for diagnostic purpose. First, it is used for visualization and histological diagnosis of intraductal papillary mucinous neoplasms. In these cases, POPS is very useful to assess the extent of malignancy and for the study of the intraductal papillary mucinous neoplasm in order to guide the surgery resection margins. Second, it is used to determine pancreatic duct strictures, particularly important in cases of chronic pancreatitis, which is associated with both benign and malignant strictures. Therefore POPS allows differentiation between benign and malignant disease and allows mapping the extent of the tumor prior to surgical resection. Also tissue sampling is possible, but it can be technically difficult because of the limited maneuverability of the biopsy forceps in the pancreatic ducts. Pancreatoscopy can also be used for therapeutic purposes, such as pancreatoscopy-guided lithotripsy in chronic painful pancreatitis with pancreatic duct stones. The available data for the moment suggests that, in selected patients, pancreatoscopy has an important and promising role to play in the diagnosis of indeterminate pancreatic duct strictures and the mapping of main pancreatic duct intraductal papillary mucinous neoplasms. However, further studies are necessary to elucidate and validate the pancreatoscopy role in the therapeutic algorithm of chronic pancreatitis.

Endoscopic diagnosis of cystic lesions of the pancreas

Endoscopic methods are increasingly used in the diagnosis of cystic lesions of the pancreas. The two major endoscopic approaches are endoscopic ultrasonography (EUS) and transpapillary diagnosis. EUS-guided fine-needle aspiration cytology and EUS-guided fine needle-based confocal laser endomicroscopy have been used in the differential diagnosis of mucinous and non-mucinous pancreatic cysts. EUS is the most sensitive modality for detecting mural nodules (MN) in intraductal papillary mucinous neoplasms (IPMN). Contrast-enhanced harmonic EUS (CH-EUS), as an add-on to EUS, is useful for identifying and characterizing MN. Recent studies show that CH-EUS has a sensitivity of 60-100% and a specificity of 75-92.9% for diagnosing malignant cysts. Intraductal ultrasonography and peroral pancreatoscopy are especially useful for detecting MN and IPMN. A recent meta-analysis showed that cytological assessment of pancreatic juice using a transpapillary approach had a pooled sensitivity, specificity, and accuracy of 35.1%, 97.2%, and 92.9%, respectively, for diagnosing malignant IPMN. Further studies are warranted to determine the indications for each of these novel techniques in assessing cystic lesions of the pancreas.

Assessment of cell block technique in head and neck pathology diagnoses: A preliminary study

OBJECTIVE

The head and neck region is a composite site made of multiple tissue components. These tissues when affected by disease or pathology present with an array of changes in the tissue architecture and pattern. It is essential to visualize the cellular details and tissue patterns for accurate diagnosis and treatment planning. Aspiration cytology primarily makes use of the cellular details for diagnosing lesions of the head and neck. Despite the promising results, its use is still limited in certain cases of the head and neck. The reason implicated could be the indiscernible appearance of cells in the absence of tissue integrity. In this regard, cell blocks are known to facilitate the visualization of the cytomorphological as well as the tissue arrangement patterns. Thus, the present study was designed to evaluate the role of cell block cytology in the diagnosis of various lesions of the head and neck.

METHODS

Odontogenic lesions, epithelial carcinomas and connective tissue pathology of the head and neck origin were included in the study (n = 45). Aspiration cytology smears and cell block diagnosis were compared with tissue biopsy diagnosis for determining their sensitivity (%) and diagnostic efficacy.

RESULTS

Cell blocks showed distinct preservation of the architectural pattern. In case of fluid-filled lesions, the contents were preserved and correlated with the tissue biopsy results. The results of cell blocks were similar to that of tissue biopsy in majority of the cases (95.56%).

CONCLUSION

We recommend using cell blocks as a part of routine laboratory practice for all head-neck cases.

Efficacy, Safety, and Outcomes of Endoscopic Retrograde Cholangiopancreatography With Per-Oral Pancreatoscopy: A Multicenter Experience

INTRODUCTION

Per-oral pancreatoscopy can be used for both evaluation and treatment of pancreatic duct stones during endoscopic retrograde cholangiopancreatography, evaluating and treating pancreatic duct strictures of indeterminate etiology, and visual inspection and direct biopsy of pancreatic duct mucosa for diagnosis of intraductal papillary mucinous neoplasm (IPMN). We aim to describe the efficacy, safety, and outcomes of pancreatoscopy in a large, multicenter series of patients.

MATERIALS AND METHODS

A multicenter retrospective review was conducted of all patients who underwent per-oral pancreatoscopy at 2 large tertiary-care medical centers. Review of relevant medical records, laboratory data, imaging studies, endoscopic procedure notes, telephone follow-up notes, and progress notes was performed.

RESULTS

Thirty-three patients underwent 41 pancreatoscopy procedures. Indications included: 20 (48.8%) for diagnosis and treatment of pancreatic duct stones, 16 (39%) for investigation of IPMN, and 5 (12.2%) for evaluation of pancreatic duct strictures.In 20 procedures performed for stone disease, complete pancreatic duct clearance was achieved in 17 of 20 (85%) cases. Strictures were successfully dilated in 5 of 5 (100%) procedures. Direct visualization and biopsy demonstrated IPMN in 11 of 11 (100%) cases. Adverse events occurred in 3 of 41 (7.3%) of procedures, all of which were mild.

CONCLUSIONS

In this large series, we demonstrate that in patients with difficult to manage stone disease, strictures and possible malignant ductal pathology, pancreatoscopy is an effective and safe tool that can facilitate both diagnosis and effective therapy. Adverse events in our study were mild and within acceptable limits, further demonstrating that this is a safe procedure that should be offered to appropriate patients.

Pancreatic juice cytology with immunohistochemistry to detect malignancy and histologic subtypes in patients with branch duct type intraductal papillary mucinous neoplasms of the pancreas

BACKGROUND AND AIMS

The aim of this study was to elucidate the efficacy of pancreatic juice cytology with the cell-block method (CB-PJC) for the determination of surgery in patients with branch duct intraductal papillary mucinous neoplasm (BD-IPMN).

METHODS

In 138 patients with BD-IPMN from whom pancreatic juice was collected under ERCP for CB-PJC, we retrospectively evaluated the following: (1) the rate of successfully evaluated CB-PJC; (2) the ability of CB-PJC to diagnose malignancy and to identify pathologic subtypes in resected BD-IPMNs; (3) the rate of development into invasive cancer and progression of BD-IPMNs in patients with BD-IPMNs diagnosed as benignancy by CB-PJC; and (4) post-ERCP adverse events.

RESULTS

(1) The success rate of CB-PJC was 89.9%. (2) The sensitivity and specificity of CB-PJC for preoperative diagnosis of malignancy were 50% and 100%, respectively, with only hematoxylin and eosin staining, whereas they were 79% and 100%, respectively, by adding immunohistologic staining. The agreement rate of the preoperative subtypes by CB-PJC with the subtypes of resected specimens was 93%. (3) The onset of invasive cancer was not detected at all on imaging studies, whereas the progression of IPMN was detected in 14 patients. Multivariate analysis revealed the risk factor of progression to be non-gastric type. The cumulative 5-year progression rate in this group was 89%. (4) Post-ERCP pancreatitis developed in 13 patients (7.7%).

CONCLUSIONS

The diagnostic efficacy of preoperative CB-PJC for malignant BD-IPMN was excellent. The results may suggest the feasibility of applying preoperative subtyping by CB-PJC for decisions as to whether surgery is indicated.

Innovations in Intraductal Endoscopy: Cholangioscopy and Pancreatoscopy

Cholangioscopy was first performed in the 1970s. We now use the term cholangiopancreatoscopy (CP) to reflect the wider application of these miniature reusable dual-operator "mother-daughter" endoscope systems and now fully disposable and digital single-operator optical catheters for evaluating the biliary or pancreatic duct. Cholangioscopy is an established modality for the management of large biliary stones and for the diagnosis and exclusion of biliary tumors. Pancreatoscopy is increasingly being performed to treat difficult pancreatic duct stones and may be used to distinguish malignant from benign ductal pathology. This review covers available CP technologies, indications, technique, efficacy, and complications.

Current roles of endoscopy in the management of intraductal papillary mucinous neoplasm of the pancreas

Intraductal papillary mucinous neoplasm (IPMN) of the pancreas is characterized by intraductal papillary proliferation of mucin-producing epithelial cells that exhibit various degrees of dysplasia. IPMN is classified into four histological subtypes (gastric, intestinal, pancreatobiliary, and oncocytic) according to its histomorphological and immunohistochemical characteristics. Endoscopic retrograde cholangiopancreatography plays a crucial role in the evaluation of these features of IPMN. Endoscopic ultrasonography (EUS) has proven to be more sensitive than computed tomography or magnetic resonance imaging for early detection of malignancy. The present review addresses the current roles of endoscopy and related techniques in the management of IPMN. The particular focus is on diagnosing IPMN and malignancy within IPMN, detecting pancreatic cancer concomitant with IPMN, differentiating the epithelial subtypes of IPMN, determining the optimal strategy for the management of branch duct IPMN, and discussing innovative endoscopic technology related to IPMN. The disadvantages of endoscopic examinations of IPMN and different attitudes toward EUS-guided fine-needle aspiration for IPMN between Japan (negative) and other countries (active) are also discussed.

Single-operator pancreatoscopy is helpful in the evaluation of suspected intraductal papillary mucinous neoplasms (IPMN)

BACKGROUND AND OBJECTIVE

Even when advanced cross-sectional imaging modalities have been employed, endoscopic evaluation of intraductal papillary mucinous neoplasms (IPMN) is often required in order to assess the final character and extent of lesions. The current study addresses the use of SpyGlass single-operator peroral pancreatoscopy in suspected IPMN.

DESIGN

A prospective, non-randomized exploratory cohort study.

SETTING

Single-center.

PATIENTS AND INTERVENTION

A prospective study-cohort of 44 consecutive patients in a single tertiary referral center who underwent ERCP and peroral pancreatoscopy, was prospectively collected between July 2007 and March 2013 because of a radiological signs of IPMN. These IPMN-findings were discovered incidentally in 44% of the cases.

MAIN OUTCOME MEASUREMENTS

Diagnostic accuracy (specificity & sensitivity) and complications.

RESULTS

The targeted region of the pancreatic duct was reached with the SpyGlass system in 41 patients (median age 65 years, 41% female). Three patients were excluded from analysis because of failed deep cannulation of the pancreatic duct. Brush cytology was taken in 88% and direct biopsies in 41%. IPMN with intermediate or high-grade dysplasia was the main final diagnosis (76%) in 22 patients who had surgery. Out of the 17 patients with a final diagnosis of MD-IPMN, 76% were correctly identified by pancreatoscopy. Of the 9 patients with a final diagnosis of BD-IPMN, the pancreatoscopy identified 78% of the cases correctly.The incidence of post-ERCP pancreatitis was 17%. Pancreatoscopy was found to have provided additional diagnostic information in the vast majority of the cases and to affect clinical decision-making in 76%.

LIMITATIONS

Single-center study.

CONCLUSIONS

Single-operator peroral pancreatoscopy contributed to the clinical evaluation of IPMN lesions and influenced decision-making concerning their clinical management. The problem of post-procedural pancreatitis needs further attention.

Diagnostic yield of endoscopic retrograde cholangiopancreatography-based cytology for distinguishing malignant and benign intraductal papillary mucinous neoplasm: systematic review and meta-analysis

BACKGROUND AND AIM

Published studies have revealed the diagnostic yield of cytology obtained from endoscopic retrograde cholangiopancreatography (ERCP) in distinguishing malignant and benign intraductal papillary mucinous neoplasm (IPMN). However as a result of small sample sizes, the overall magnitude of benefit is unknown. Additionally, the optimal endoscopic procedure for cytology acquisition is also unclear. The aim of the present study was to evaluate the diagnostic yield of ERCP-based cytology in patients with IPMN and clarify the optimal sampling technique.

METHODS

Relevant studies with a reference standard of definitive surgical histology were identified via MEDLINE and SCOPUS. Malignant IPMN included invasive adenocarcinoma, carcinoma in situ, and high-grade dysplasia. For ERCP, studies using aspiration, brush, and lavage cytology were included. The main objective was the diagnostic yield (pooled sensitivity, specificity, positive likelihood ratio, negative likelihood ratio) of cytology obtained from ERCP to distinguish malignant and benign IPMN.

RESULTS

Meta-analysis of 13 international studies with 483 IPMN patients was conducted. Pooled sensitivity was 35.1%, specificity 97.2%, and accuracy 92.9%. Among the three ERCP techniques, lavage cytology showed the best diagnostic ability (sensitivity 45.8%, specificity 97.9%). Malignant IPMN were observed in 45.1% (218/483) of patients in ERCP studies.

CONCLUSIONS

Cytology from ERCP has good specificity but poor sensitivity in distinguishing benign from malignant IPMN. Newer techniques or markers are needed to improve diagnostic yield.

Peroral pancreatoscopy using the SpyGlass system for the assessment of intraductal papillary mucinous neoplasm of the pancreas

BACKGROUND

Peroral pancreatoscopy (POPS) using a mother-baby endoscope system is often useful for assessment of intraductal papillary mucinous neoplasm (IPMN) of the pancreas with main pancreatic duct (MPD) involvement, but is not widely used for several reasons. The aim of this study was to evaluate the usefulness of the SpyGlass Direct Visualization System for assessment of IPMN.

METHODS

Seventeen patients diagnosed with possible IPMN with MPD dilation underwent peroral pancreatoscopy using the SpyGlass system at our institution. The quality of visualization and the sensitivities of cytological and pathological investigations for diagnosing malignant lesions were evaluated.

RESULTS

Peroral pancreatoscopy was performed using the SpyScope in 12 patients and an endoscopic retrograde cholangiopancreatography (ERCP) catheter in five patients. Sufficient visualization was achieved in 92% of cases using the SpyScope and 40% of cases using the ERCP catheter. Biopsy under direct visualization was successful in seven patients. Biopsy specimens showed adenocarcinoma in one patient, benign neoplastic epithelium in five patients, and regenerative changes in one patient; and had 25% sensitivity and 100% specificity for detecting malignancy. SpyGlass pancreatoscopy with irrigation cytology had 100% sensitivity and 100% specificity for detecting malignancy. SpyGlass pancreatoscopy was useful for determining the operative excision line in three patients. There were no severe procedure-related adverse events.

CONCLUSIONS

Peroral pancreatoscopy using the SpyGlass system seems to be feasible and useful for assessment of IPMN with a dilated MPD.

Usefulness of cell block cytology for preoperative grading and typing of intraductal papillary mucinous neoplasms

BACKGROUND

Precise histological diagnosis is important for the successful management of intraductal papillary mucinous neoplasms (IPMNs).

OBJECT

The object of this study was to determine whether cell block cytology is useful for preoperative cytomorphological grading and typing of IPMNs.

METHODS

The subjects were 23 patients with IPMN from whom pancreatic juice was collected via a pancreatic catheter and who subsequently underwent pancreatic resection.

RESULTS

In 20 of the 23 cases, the quantity of cells collected for cell block cytology was sufficient to enable typing and grading of the IPMN. The rates of consistency between the results of typing and grading by cell block cytology and histological examination of the surgical specimen were 95% and 80%, respectively. Typing of the 10 main-duct/mixed-duct-type IPMNs by cell block cytology yielded 5 gastric types, 3 intestinal types, 1 oncocytic type, and 1 pancreatobiliary type, and the typing was consistent with the surgical diagnosis in all 10 cases. The results of typing of the branch-duct-type IPMNs by cell block cytology were identical to the results of histological typing in the surgical specimens in every case but one. However, the specificity of cell block cytology for grading IPMNs was 55.6%.

CONCLUSIONS

The cell block cytological findings were fairly consistent with the histopathological features of the surgical specimens, thereby indicating that cell block cytology may be useful for preoperative and typing of IPMNs, but only play a supplementary role in grading IPMNs.

Pancreatic duct lavage cytology with the cell block method for discriminating benign and malignant branch-duct type intraductal papillary mucinous neoplasms

BACKGROUND

Differentiation between benign and malignant branch-duct type intraductal papillary mucinous neoplasms (IPMNs) remains challenging.

OBJECTIVE

To examine the usefulness of pancreatic duct lavage cytology with cell block method for discriminating benign and malignant branch-duct type IPMNs.

PATIENTS AND METHODS

Between December 2007 and April 2011, patients with branch-duct type IPMNs having mural nodules on EUS were examined by pancreatic duct lavage cytology by using the cell block method. Cell block sections underwent hematoxylin and eosin staining and mucin immunostainings (MUCs 1, 2, 5AC, and 6).

DESIGN

Single-center, prospective study.

SETTING

Academic medical center.

MAIN OUTCOME MEASUREMENTS

The sensitivity and specificity of cytology were assessed. The agreement between cytological and histological results for MUC was also examined.

RESULTS

Cytology with this method was investigated in 44 patients. Cell block diagnosis was cancer positive (class V or IV) in 11 patients and negative (classes I, II, III, and noninformative) in 33. The sensitivity, specificity, and positive and negative predictive values of this method were 92%, 100%, 100%, and 97%, respectively. The cytological and histological results of MUCs 1, 2, 5AC, and 6 agreed in 88% (15/17), 94% (16/17), 88% (15/17), and 100% (17/17), respectively.

LIMITATIONS

Single center and small number of patients.

CONCLUSIONS

Pancreatic duct lavage cytology with the cell block method may be useful to differentiate between benign and malignant IPMNs preoperatively and as well as to determine their mucin type.

Usefulness of brush cytology combined with pancreatic juice cytology in the diagnosis of pancreatic cancer: significance of pancreatic juice cytology after brushing

OBJECTIVES

Pancreatic juice cytology (PJC) and brush cytology (BC) performed during endoscopic retrograde cholangiopancreatography could make a definite diagnosis of pancreatic cancer. The aim of this study was to improve the diagnostic value of cytology performed during endoscopic retrograde cholangiopancreatography in the diagnosis of pancreatic cancer.

METHODS

The subjects comprised 127 patients with pancreatic ductal adenocarcinoma (PDAC) and 74 with benign pancreatic duct stricture mimicking PDAC. Final diagnosis was confirmed based on histopathology by resection or on more than 1 year of follow up. Pancreatic juice cytology was examined before and after BC. And the sensitivity of PJC combined with BC was examined.

RESULTS

No malignancy was detected by PJC or by BC in patients with benign pancreatic duct strictures (specificity, 100%). In those with PDAC, the sensitivity of PJC before and after brushing was 21.3% and 40.9%, respectively; that of BC was 48.8%. Of 65 patients with PDAC, in whom neither PJC before brushing nor BC indicated malignancy, 16 were diagnosed with pancreatic cancer using PJC after brushing. Brush cytology combined with PJC after brushing significantly raised the diagnostic sensitivity for PDAC to 61.4%.

CONCLUSIONS

Diagnosis of pancreatic cancer based on BC combined with PJC after brushing was more reliable than PJC before brushing or BC.

Size of mural nodule as an indicator of surgery for branch duct intraductal papillary mucinous neoplasm of the pancreas during follow-up

BACKGROUND

A mural nodule is a strong predictive factor for malignancy in branch duct intraductal papillary mucinous neoplasm (IPMN) of the pancreas, but the nodule size has hardly been considered. The aim of this study was to investigate whether a mural nodule of 10 mm was appropriate as an indicator of surgery for IPMN during follow-up.

METHODS

The follow-up outcomes of 100 patients who had branch duct IPMN without mural nodules or who had branch duct IPMN with mural nodules of less than 9 mm in a tertiary care setting were investigated retrospectively. The patients underwent abdominal ultrasound (US) every 3 months and additional imaging examinations or cytologic examination of pancreatic juice when necessary. Surgery was recommended to them when a mural nodule developed or when a nodule enlarged and reached 10 mm.

RESULTS

During an average follow-up period of 97 months, branch duct IPMNs developed mural nodules that reached 10 mm in 5 patients (0.62% per year). In one patient the IPMN was revealed to be non-invasive carcinoma by resection, 1 IPMN was shown to be malignant by further follow-up, and 3 were not resected because of refusal or the patient's age. In 7 patients, mural nodules stayed within 9 mm. The remaining 88 patients lacked mural nodules in their branch duct IPMNs throughout the follow-up. The occurrence of invasive carcinoma around the IPMN was not indicated by imaging examinations in any patient. Univariate analysis showed that the size of the cyst at baseline significantly predicted the development of a mural nodule that reached 10 mm during follow-up (P = 0.05).

CONCLUSIONS

A mural nodule of 10 mm is appropriate as an indicator of surgery in the follow-up of branch duct IPMN.

Endoscopic retrograde cholangiopancreatography for non-gastroenterologists: what you need to know

Endoscopic retrograde cholangiopancreatography (ERCP) represents the most powerful and widely employed platform for pancreaticobiliary interventions. Endoscopic retrograde cholangiopancreatography allows diagnosis and treatment of a broad spectrum of diseases of the pancreaticobiliary tree that are both benign and malignant in nature. Endoscopic retrograde cholangiopancreatography continues to evolve rapidly, and non-gastroenterologists need to understand the indications, contraindications, limitations, and role of ERCP to effectively manage and coordinate the care of patients with known or suspected pancreaticobiliary disease. This article will review the role of ERCP in detail to further an understanding of the procedure as a whole and to assess when referral of a patient for an ERCP or other related test is indicated.

A natural course of main duct intraductal papillary mucinous neoplasm of the pancreas with lower likelihood of malignancy

OBJECTIVES

Main duct intraductal papillary mucinous neoplasms (IPMNs) of the pancreas include neoplasms with varying likelihood of progression to malignancy. The aim of this study was to investigate a natural course of main duct IPMNs with a lower likelihood of malignancy.

METHODS

Twenty main duct IPMNs with a lower likelihood of malignancy, which was defined as mural nodule of less than 10 mm or no visualized mural nodule, and negative result of cytological examination of pancreatic juice, underwent regular ultrasound every 3 months. Special imaging examinations and additional pancreatic juice cytological examination were performed when necessary. Surgery was considered when a mural nodule enlarged to 10 mm or the cytological examination result indicated malignancy.

RESULTS

During a mean of 70 months, 12 IPMNs (60%) did not progress and 6 (30%) progressed within a lower likelihood of malignancy. The remaining 2 IPMNs (10%) progressed to meet the criteria for resection, underwent surgery, and were demonstrated to be carcinomas.

CONCLUSIONS

Main duct IPMN with a lower likelihood of malignancy was divided into 2 subgroups: neoplasm that progressed and that which did not progress during its natural course. The former should be resected considering its malignant potential, whereas the latter may be managed nonsurgically as long as it stays unchanged.

Nonprevention of post-endoscopic retrograde cholangiopancreatographic pancreatitis by pancreatic stent after aspiration of pure pancreatic juice in patients with intraductal papillary mucinous neoplasms of the pancreas

OBJECTIVES

The objective of this study was to evaluate the efficacy of a pancreatic stent regarding the prevention of post-endoscopic retrograde cholangiopancreatography (ERCP) pancreatitis after aspiration of pure pancreatic juice in patients with intraductal papillary mucinous neoplasms.

METHODS

A retrospective study was made to assess the outcome in 121 consecutive patients with intraductal papillary mucinous neoplasms who underwent endoscopic aspiration of pure pancreatic juice for cytologic examination between July 2001 and October 2007. From July 2001 to March 2004, 58 patients did not undergo pancreatic stent insertion (the no-stent [nS] group). The remaining 63 patients did undergo stent insertion (stent [S] group).

RESULTS

The overall incidences of post-ERCP pancreatitis was 11 (9.1%). The incidences of post-ERCP pancreatitis in the S and nS groups were 8 (12.7%) and 3 (5.2%; P = 0.21), respectively. In the male patients and the patients with a smaller diameter of the main pancreatic ducts, post-ERCP pancreatitis was seen more frequently in those in the S group (13% and 21%, respectively) than in those in the nS group (0% and 0%, respectively; P = 0.04, 0.03).

CONCLUSIONS

The pancreatic stent did not seem to decrease the incidence of post-ERCP pancreatitis in patients with intraductal papillary mucinous neoplasms. Furthermore, the pancreatic stent seems to be potentially detrimental in male patients and in patients with small-diameter main pancreatic ducts.

Cholangiopancreatoscopy for targeted biopsies of the bile and pancreatic ducts

Establishing a tissue diagnosis in patients with suspected pancreaticobiliary malignancies remains challenging. Endoscopic retrograde cholangiopancreatography (ERCP)-based sampling methods have been reviewed in a previous issue of this journal but, unfortunately, the diagnostic yield continues to be inadequate in a significant minority of patients. The availability and image quality of cholangioscopy and pancreatoscopy have advanced in the last few years and our ability to make a diagnosis on imaging alone is improving. However, a definitive diagnosis requires tissue; cholangiopancreatoscopy allows targeted biopsies of the epithelium of the biliary and pancreatic ducts. This article reviews the evidence that cholangioscopy- and pancreatoscopy-guided biopsies improves diagnostic yield over ERCP-based tissue sampling techniques.

Peroral pancreatoscopy in the diagnosis and management of intraductal papillary mucinous neoplasia and indeterminate pancreatic duct pathology

Peroral pancreatoscopy (POP) is an exciting modality for the evaluation of pancreatic diseases. It has proved efficacy in the evaluation of suspected intraductal papillary mucinous neoplasia and allows for a determination of the presence and extent of pancreatic duct involvement. When other imaging modalities are inconclusive, POP seems a useful adjunct in the evaluation of indeterminate pancreatic duct strictures and permits tissue sampling under direct vision. Despite recent advances, refinements in endoscope caliber, tip deflection, and optics are still required for more routine application in pancreatic diseases.

Clinical fate of branch duct and mixed forms of intraductal papillary mucinous neoplasia of the pancreas

AIMS

The aim of the present study was to assess the clinical fate of, and to gain new insights into, branch duct and mixed (predominantly main duct type) forms of intraductal papillary mucinous neoplasia of the pancreas (IPMN).

METHODS

During a 17-year period, 99 successive IPMN patients (52 men, 47 women; mean age, 64 years) were included and divided into two groups for further comparison: one group had branch duct IPMN, whereas the other had mixed IPMN.

RESULTS

Patients from the mixed IPMN group (n = 52) displayed a greater rate of symptoms (83% vs 55%, P = 0.004), pancreatic resection (67% vs 38%, P = 0.007), malignancy (35% vs 13%, P = 0.017) and death (15% vs 4%, P = 0.09) than those from the branch duct IPMN group. A 38-month follow up of non-operated, symptom-free patients confirmed that more than 85% of branch duct IPMN patients were asymptomatic without evidence of malignancy. Borderline lesions and carcinoma are found in up to 50% of symptomatic resected branch duct IPMN cases.

CONCLUSION

Patients with the mixed form of IPMN as well as with symptomatic branch duct IPMN should require pancreatic resection because of symptoms and the risk for malignancy. In silent branch duct IPMN without radiological signs of malignancy, a non-operative watch-and-wait strategy can be discussed.

Usefulness of human telomerase reverse transcriptase in pancreatic juice as a biomarker of pancreatic malignancy

OBJECTIVES

Human telomerase reverse transcriptase (hTERT), one of the subunits of telomerase, is a promising diagnostic marker for pancreatic cancer. In the present study, we did a large-scale analysis of 115 preoperative pancreatic juice specimens to evaluate the feasibility of detection of hTERT expression by immunohistochemistry for preoperative diagnosis of pancreatic malignancy.

METHODS

The expression of hTERT was examined by immunohistochemistry in preoperative pancreatic juice samples.

RESULTS

In pancreatic juice samples, hTERT expression was detectable in 84% of pancreatic ductal adenocarcinomas (PDACs), whereas 62% of PDACs were positive by cytology. In intraductal papillary mucinous neoplasms (IPMNs), hTERT expression was detectable in 88% of malignant IPMNs, whereas only 22% were positive by cytology. The sensitivity, specificity, and overall accuracy of hTERT expression for differentiation between carcinoma and other benign diseases were 85.1%, 82.1%, and 84.3%, respectively, whereas the same values for cytologic accuracy were 47.1%, 89.3%, and 57.4%, respectively. When the results of cytology and hTERT expression were combined, the sensitivity and overall accuracy increased to 92.0% and 87.8%, respectively.

CONCLUSIONS

Our results suggested that the assessment of hTERT expression in preoperative pancreatic juice increased the sensitivity and accuracy of diagnosis of PDACs and malignant IPMNs without using special techniques.

Application of per oral cholangiopancreatoscopy in pancreatobiliary diseases

Pancreaticobiliary ductal diseases are largely investigated by indirect imaging techniques. Therefore, the pathology of up to 30% of cases remains undetermined. Cholangiopancreatoscopy allows direct visualization of ductal abnormalities with the ability to sample tissue and deliver a number of endotherapies. The technique can be broadly categorized into either two-operator or single-operator systems. Both systems provide important diagnostic information in the investigation of undetermined biliary or pancreatic strictures, intraductal papillary mucinous neoplasia, occult ductal malignant changes in patients with primary sclerosing cholangitis and occult intraductal stones in patients with complex biliary stone diseases. Therapeutically, cholangiopancreatoscopy-guided endotherapies provide a highly effective and safe alternative to surgery for patients with difficult extrahepatic and intrahepatic ductal stones that are not amenable to conventional endoscopic extraction by endoscopic retrograde cholangiopancreatography. The clinical application of cholangiopancreatoscopy, however, will be limited unless the technology is further refined to improve its durability, image quality, therapeutic capability and technical feasibility.

Branch duct intraductal papillary mucinous neoplasms in a retrospective series of 190 patients

Background

A consensus conference has recommended close observation of branch duct intraductal papillary mucinous neoplasms (BD-IPMNs) smaller than 30 mm, without symptoms or mural nodules. This study investigated whether these recommendations could be validated in a single-centre experience of BD-IPMNs.

Methods

Some 190 patients with radiological imaging or histological findings consistent with BD-IPMN were enrolled between 1998 and 2005. Those with less than 6 months' follow-up and no histological confirmation were excluded.

Results

BD-IPMN was diagnosed by computed tomography and pancreatography in 105 patients and pathologically in 85. Eighteen patients had adenoma, 53 borderline malignancy, five carcinoma in situ and nine invasive carcinoma. Findings associated with malignancy were the presence of radiologically suspicious features (P &lt; 0·001) and a cyst size of at least 30 mm (P = 0·001). Had consensus guidelines been applied, 54 patients would have undergone pancreatic resection, whereas only 28 of these patients actually had a resection; 12 of the latter patients had a malignancy compared with none of the 26 patients who were treated conservatively.

Conclusion

A simple increase in cyst size is not a reliable predictor of malignancy. Observation is recommended for patients with a BD-IPMN smaller than 30 mm showing no suspicious features on imaging.

Pancreatic-duct-lavage cytology in candidates for surgical resection of branch-duct intraductal papillary mucinous neoplasm of the pancreas: should the International Consensus Guidelines be revised?

BACKGROUND

The International Consensus Guidelines are helpful for the management of branch-duct intraductal papillary mucinous neoplasms (IPMNs), because they allow us to exclude malignancy. However, it is not possible to predict malignancy with certainty, and further preoperative differentiation between benign and malignant IPMNs is required to avoid the false-positive results.

OBJECTIVE

To examine the usefulness of pancreatic-duct-lavage cytology by using an originally designed double-lumen catheter for discriminating benign and malignant IPMNs of the branch-duct type in candidates for surgical resection based on the International Consensus Guidelines.

PATIENTS

Pancreatic-duct-lavage cytology was investigated in 24 patients with branch-duct IPMNs who underwent surgical resection based on the International Consensus Guidelines, namely, they either had intramural nodules or the ectatic branch duct was >30 mm in diameter.

DESIGN

Single-center retrospective study.

SETTING

Academic medical center.

MAIN OUTCOME MEASUREMENTS

The sensitivity and specificity of pancreatic-duct-lavage cytology for discriminating benign from malignant IPMNs.

RESULTS

More than 30 mL of pancreatic-duct-lavage fluid was obtained from each patient, and there were no patients with noninformative results. The sensitivity, specificity, positive predictive value, and negative predictive value of the cytologic diagnosis were 78%, 93%, 88%, and 88%, respectively.

LIMITATIONS

Single-center and small number of patients.

CONCLUSIONS

Pancreatic-duct-lavage cytology can improve differentiation between benign and malignant IPMNs of the branch-duct type in candidates for surgical resection based on the International Consensus Guidelines.

Quantitative analysis of hTERT mRNA levels in cells microdissected from cytological specimens

Clinicians frequently require cytopathological assessment of tumor samples for preoperative diagnosis, but in some specimens, diagnosis remains inconclusive after cytological examination. To date, several molecular markers, including human telomerase reverse transcriptase (hTERT), have been assessed for the ability to detect malignancy. However, analyses using whole cytological specimens are generally affected by contamination of untargeted cells. The present study investigated the feasibility of more sensitive examination by quantitative mRNA analysis of target cells microdissected from cytological specimens. Laser capture microdissection (LCM) was used to obtain target cells from cytological specimens. hTERT mRNA levels were then measured in target cells by quantitative real-time RT-PCR (qRT-PCR). The effect of RNA fragmentation on qRT-PCR was also assessed. Total RNA from cytological specimens was sometimes fragmented to a large degree. To avoid the effect of RNA fragmentation, gene specific priming and PCR primers generating short PCR products were used and no difference in delta Ct values between fragmented and non-fragmented RNA were found. hTERT mRNA levels were measured in cells microdissected from 33 cytological specimens. The levels of hTERT mRNA were significantly higher in malignant cases compared to those in non-malignant cases (P = 0.0003). The sensitivity was 96.2%, even when the specificities were 100%. High levels of hTERT mRNA were also found in three cases that were not diagnosed as malignant by cytological examination. Quantitative assessment of hTERT mRNA levels in cells microdissected from cytological specimens is a potential diagnostic tool to potentiate cytological examination in diagnosing malignancy.

Endoscopic diagnosis and treatment of pancreatic cysts

Pancreatic cystic neoplasms have emerged as an important new opportunity for many disciplines to participate in the diagnosis and management of early pancreatic neoplasia. With an increase in an understanding of these lesions and their potential for malignant transformation, there has been a dramatic increase in the frequency of diagnosis. We critically examined the literature on diagnostic methods for pancreatic cystic lesions over the past 5 years. The methods of endoscopic pancreatic pseudocyst drainage and clinical outcomes are also discussed. Morphologic studies of cystic lesions using cross-sectional imaging or endoscopic ultrasound have a low diagnostic rate. Cyst fluid analysis with the use of tumor markers (eg, carcinoembryonic antigen) increases the accuracy of diagnosis. The management of cystic lesions is heavily dependent on the type of cyst, the neoplastic potential, and the risk of surgery. The traditional therapy is pancreatic resection and not cyst enucleation. In contrast to cystic neoplasms, pseudocysts are localized collections of inflammatory fluid that mimic cystic neoplasms. The fluid collections arise from chronic pancreatitis and ductal leaks. Because pseudocysts have no neoplastic potential, they can be drained rather than resected. Drainage can be safely accomplished with external catheters or endoscopically with internal catheters. As we learn more about the pathophysiology of the various cystic lesions, treatment will be tailored to the specific cyst lesion. Endoscopic ultrasound has an important role in the characterization of pancreatic cystic lesions and helps in selection of the optimal treatment modality.

Detection of human telomerase reverse transcriptase (hTERT) expression in tissue and pancreatic juice from pancreatic cancer

BACKGROUND

Human telomerase reverse transcriptase (hTERT), a catalytic subunit of telomerase, is a promising diagnostic candidate for pancreatic cancer. To evaluate the feasibility of immunohistochemistry (IHC) for the diagnosis of pancreatic cancer, hTERT expression and telomerase activity were assayed in pancreatic tissues, ex vivo brushing, and pancreatic juice samples with various pancreatic diseases.

METHODS

Telomerase activity was analyzed using the TRAP assay and hTERT was examined by IHC in 85 pancreatic tumor samples, 17 ex vivo pancreatic duct brushings, and 27 pancreatic juice samples.

RESULTS

In tissue samples, telomerase activity was positive in 83% of invasive ductal adenocarcinomas (IDCs) when the specificity was set at 100%, while hTERT was highly expressed in 88% of IDCs. In intraductal papillary mucinous neoplasms (IPMNs), the levels of telomerase activity increased gradually during progression, while hTERT expression was detectable in 8 of 8 malignant IPMNs and 1 of 2 borderline IPMNs. In pancreatic juice samples, 10 of 11 IDCs and 3 of 4 malignant IPMNs expressed hTERT, in which seven samples were not diagnosed as malignant on cytologic exam. The diagnoses of pancreatic cancer based on hTERT IHC exhibited high rates of sensitivity (87%), specificity (92%), and overall accuracy (89%), whereas the sensitivity of cytologic examination was 53%. The additional assessment of hTERT expression and telomerase activity could improve the sensitivity up to 100%.

CONCLUSIONS

Our results suggested that hTERT expression in epithelia indicates malignant transformation in pancreatic tumors and immunohistochemical detection of hTERT in cells derived from pancreatic juice provides a potent method for cancer diagnosis.

Intraductal papillary mucinous neoplasm--when to resect?

Based on the experience to date with IPMNs, the approach to patients remains relatively complex. A meticulous and careful approach to diagnosis, oncologic risk assessment, operative planning, and surveillance is needed to adequately address these lesions. Indications for resection in patients with IPMN are (1) cancer, (2) cancer prevention in patients at high risk for malignant transformation, and (3) management of symptoms. Differentiating patients who have IPMNs by type is an important initial step in providing optimal care (Fig. 6). In patients with MPD involvement (main- and mixed-type IPMN), the risk of malignancy at resection is too high to justify nonoperative management unless comorbidity or patient preference precludes operation. Until better preoperative biomarkers of malignancy in main duct-involved IPMNs are available, it is our recommendation that all patients who are fit should undergo resection of the entire involved segment with appropriate adjustment and extension based on intraoperative pathology. Total pancreatectomy may be indicated for diffuse main duct involvement. In the more difficult and debated cohort (i.e., patients with side branch disease only), a more strategic approach to whether to resect is appropriate. Patients with malignant cytopathology, concerning radiologic features (i.e., mural nodules, associated mass), or symptoms attributable to IPMNs should be offered resection. Importantly, specific symptoms have variable importance in terms of oncologic risk and are worth characterizing in individual patients. Size alone should not be the determining oncologic factor for resection, although we acknowledge that the literature is unclear in this regard. Size of IPMNs (or any other cystic lesion) may be a nononcologic indication to resect for symptom control and when size or anticipated growth may complicate the ability to safely extirpate the lesion. Other factors that should be considered in determining whether to resect are number of lesions, need for prolonged surveillance, inability to adequately perform noninvasive surveillance (e.g., contraindication to MRI), difficulty in surveillance (extensive/diffuse multifocal disease), and patient tolerance of risk. The decision to resect in patients undergoing primary surveillance or secondary surveillance for IPMN should be similar to the indications for primary resection noted previously. The optimal surveillance regimen, however, is unknown. The optimal surveillance regimen depends on the timing and incidence of "recurrence" and "new metachronous IPMIN development," which are not fully understood, partly because of suboptimal preoperative imaging in patients with IPMNs. To solve this mystery, surgeons and pancreatologists should be encouraged to obtain optimal and timely imaging studies before taking patients to the operating room. Patients should be followed at least annually with history and physical and optimal cross-sectional imaging. Endoscopy and cytopathologic assessment should be considered at least biannually and more often when indicated by patient symptoms or concerning radiographic features. The surveillance interval should be decreased and extent of testing increased based on patients with higher oncologic risk stratification. Although resection in patients undergoing surveillance currently follows the same algorithm as patients undergoing primary resection, assessment of the main pancreatic duct in patients undergoing secondary surveillance after segmental pancreatectomy (particularly pancreaticoduodenectomy) is complicated. Although new data continue to clarify how and when to approach IPMNs with segmental or total pancreatic resection, many questions remain unanswered. Continued efforts to uncover a more accurate natural history and behavior for IPMN continue to fill the gaps in our current understanding and practice. In the meantime, it is critical to educate and frequently restratify oncologic risk in patients based on optimal and timely data (history and physical and radiographic, endoscopic, and cytopathologic results) and rigorous follow-up to guide patients in reaching a decision of whether and when to undergo IPMN resection.

Pancreatoscopy: present and future role

Current imaging modalities do not allow for direct access to the pancreatic duct. Because of this limitation, diagnosis and assessment of pancreatic diseases require radiographic imaging and cytologic analysis. Although many of these techniques have excellent specificity for the detection of pancreatic cancer, they offer no therapeutic capabilities and are relatively poor in early detection of cancer and in differentiating chronic pancreatitis from malignancy, particularly when the conditions coexist. Currently available cholangioscopes are too large to access the pancreatic duct without sphincterotomy or balloon dilation, increasing the risk of instrumentation trauma to the pancreas. Novel, dedicated pancreatoscopes have recently been developed and are under investigation in clinical trials. Preliminary evidence suggests that these new technologies allow for direct visualization of the pancreatic ducts, with the potential for forceps biopsy in suspected malignancy and endotherapy for pancreatic calculi. Future and ongoing clinical trials will better define the utility and roles of these new endoscopy tools.