Long-term follow-up of patients with incidentally discovered pancreatic cystic neoplasms evaluated by endoscopic ultrasound

Benign pancreatic lesion on 18F-FDG PET-MRI: A case report

RATIONALE

Differentiation of benign and malignant lesions in the head of pancreas is the key. When the mass is small, it is difficult to distinguish via conventional imaging modalities. Positron emission tomography and magnetic resonance imaging (PET/MRI) can distinguish benign and malignant lesions from the perspective of metabolism, which provides a new idea for the diagnosis of pancreatic head mass.

PATIENT CONCERNS

We report the case of a 44-year-old male patient who underwent an 18F-fluorodeoxyglucose PET/MRI for medical examination. The patient did not complain of special discomfort.

DIAGNOSES

PET-MRI revealed in the head of the pancreas, there is a circular space-occupying lesion without obvious fluorodeoxyglucose accumulation, which tends to be benign based on its MRI and metabolic characteristics.

INTERVENTIONS

The patient refused further laboratory examination or ultrasound gastroscopy as there is no discomfort.

OUTCOMES

No special discomfort was found in the patient after 6 months follow-up.

LESSONS

If routine examination fails to diagnose benign or malignant pancreatic head occupying, and the patient refuses invasive examination, PET-MRI can be performed for identification.

Benefit of Extended Surveillance of Low-Risk Pancreatic Cysts After 5-Year Stability: A Systematic Review and Meta-Analysis

BACKGROUND & AIMS

Low-risk branch duct intraductal papillary mucinous neoplasms (BD-IPMNs) lacking worrisome features (WF) and high-risk stigmata (HRS) warrant surveillance. However, their optimal duration, especially among cysts with initial 5 years of size stability, warrants further investigation. We systematically reviewed the surveillance of low-risk BD-IPMNs and investigated the incidence of WF/HRS and advanced neoplasia, high-grade dysplasia, and pancreatic cancer during the initial (<5 years) and extended surveillance period (>5-years).

METHODS

A systematic search (CRD42020117120) identified studies investigating long-term IPMN surveillance outcomes of low-risk IPMN among the Cochrane Library, Embase, Google Scholar, Ovid Medline, PubMed, Scopus, and Web of Science, from inception until July 9, 2021. The outcomes included the incidence of WF/HRS and advanced neoplasia, disease-specific mortality, and surveillance-related harm (expressed as percentage per patient-years). The meta-analysis relied on time-to-event plots and used a random-effects model.

RESULTS

Forty-one eligible studies underwent systematic review, and 18 studies were meta-analyzed. The pooled incidence of WF/HRS among low-risk BD-IPMNs during initial and extended surveillance was 2.2% (95% CI, 1.0%-3.7%) and 2.9% (95% CI, 1.0%-5.7%) patient-years, respectively, whereas the incidence of advanced neoplasia was 0.6% (95% CI, 0.2%-1.00%) and 1.0% (95% CI, 0.6%-1.5%) patient-years, respectively. The pooled incidence of disease-specific mortality during initial and extended surveillance was 0.3% (95% CI, 0.1%-0.6%) and 0.6% (95% CI, 0.0%-1.6%) patient-years, respectively. Among BD-IPMNs with initial size stability, extended surveillance had a WF/HRS and advanced neoplasia incidence of 1.9% (95% CI, 1.2%-2.8%) and 0.2% (95% CI, 0.1%-0.5%) patient-years, respectively.

CONCLUSIONS

A lower incidence of advanced neoplasia during extended surveillance among low-risk, stable-sized BD-IPMNs was a key finding of this study. However, the survival benefit of surveillance among this population warrants further exploration through high-quality studies before recommending surveillance cessation with certainty.

ACR Appropriateness Criteria® Pancreatic Cyst

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

Endoscopic Ultrasound-Guided Fine-Needle Aspiration Microhistology in Asymptomatic and Symptomatic Pancreatic Cystic Lesions

OBJECTIVE

This study aimed to analyze the usefulness of endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) microhistology to detect malignancy in pancreatic cystic lesions (PCLs).

METHODS

Patients with PCLs were identified and submitted to EUS-FNA from January 2010 to January 2017. The percentage of samples suitable for diagnostic classification by microhistology and the positive and negative likelihood ratios to detect malignancy in asymptomatic (APC) and symptomatic (SPC) PCLs were determined.

RESULTS

Endoscopic ultrasound-guided fine-needle aspiration was performed in 510 patients. The resulting material was processed by microhistology and useful for diagnosis in 432 (84.2%). Clinical characteristics of APC (341) and SPC (169) revealed that APC patients were younger (P = 0.004) and had smaller PCLs (23 vs 35 mm; P < 0.001). In APC, we found more preneoplastic (38.7% vs 30.2%; P = 0.0016) and a lower number of malignant PCLs (8.2% vs 24.3%; P < 0.001). In APC and SPC, the sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of microhistology to detect malignancy were 71.4%, 99.7%, 95.2%, 97.5%, and 97.4% (k = 0.80) and 58.5%, 96.9%, 85.7%, 87.9%, and 87.6%, respectively.

CONCLUSIONS

Endoscopic ultrasound-guided fine-needle aspiration was technically feasible. Microhistology was especially useful to detect neoplastic or malignant PCLs in APC patients.

Clinical outcomes of endoscopic ultrasound-guided ethanol ablation for pancreatic cystic lesions compared with the natural course: a propensity score matching analysis

BACKGROUND

Endoscopic ultrasound-guided ethanol ablation (EUS-EA) is a recently introduced treatment for pancreatic cystic lesions (PCLs). However, clinical benefits such as survival gain and maintenance of quality of life (QOL) have not been fully established. The aim of this study was to evaluate the clinical benefits of EUS-EA compared with the natural course (NC) of PCLs.

METHODS

This retrospective comparative study of patients with PCLs investigated an EUS-EA group (n = 118) and an NC group (n = 428). Propensity score matching (PSM) analysis was applied to minimize the effects of selection bias. The overall survival as the primary outcome and the surgical resection rate and complete remission (CR) rate as the secondary outcomes were evaluated.

RESULTS

Between 84 matched pairs of both groups, there were no significant differences in the baseline clinical characteristics and the mean follow-up duration (78.88 ± 38.86, 75.90 ± 57.46 months, p = 0.694). Overall survival did not differ significantly (194.12 ± 5.60, 247.54 ± 12.70 months, p = 0.235). The surgical resection rate (4.8% versus 26.2%, p < 0.001) was significantly lower in the EUS-EA group. CR was observed only in the EUS-EA group and the CR rate was 32.1%.

CONCLUSIONS

EUS-EA for PCLs with low risk of malignancy might not be able to obtain a survival benefit, but showed maintenance of QOL by avoidance of unnecessary surgery, and a certain level of CR when compared to the NC. EUS-EA could be considered a useful treatment option for these, but careful application is needed because of the limited effects in some types of PCLs.

Progression of Pancreatic Branch Duct Intraductal Papillary Mucinous Neoplasm Associates With Cyst Size

BACKGROUNDS & AIMS

Most guidelines for management of patients with intraductal papillary mucinous neoplasms (IPMN) vary in proposed surveillance intervals and durations-these are usually determined based on expert opinions rather than substantial evidence. The progression of and optimal surveillance intervals for branch-duct IPMNs (BD-IPMN) has not been widely studied. We evaluated the progression of BD-IPMN under surveillance at a single center, and determined optimal follow-up intervals and duration.

METHODS

We performed a retrospective analysis of 1369 patients with BD-IPMN seen at Seoul National University Hospital in Korea from January 2001 through December 2016. We included only patients whose imaging studies showed classical features of BD-IPMN, and collected data from each patient over time periods of at least 3 years. We reviewed radiologic and pathologic findings, and performed linear and binary logistic regressions to estimate cyst growth.

RESULTS

The median annual growth rate of the cyst was 0.8 mm over a median follow-up time of 61 months. During surveillance, 46 patients (3.4%) underwent surgery because of disease progression after a median follow-up time (in this group) of 62 months. Worrisome features were observed in 209 patients (15.3%) during surveillance, including cyst size of 3 cm or more (n = 109, 8.0%), cyst wall thickening (n = 51, 3.7%), main pancreatic duct dilatation (n = 77, 5.6%), and mural nodule (n = 43, 3.1%). Along with annual rate of cyst growth, incidences of main pancreatic duct dilatation and mural nodules associated with the sizes of cysts at detection (P < .001).

CONCLUSIONS

In a retrospective analysis of patients with BD-IPMN followed for more than 5 years, we found most cysts to be indolent, but some rapidly grew and progressed. Surveillance protocols should therefore be individualized based on initial cyst size and rate of growth.

Endoscopic Ultrasound Imaging for Diagnosing and Treating Pancreatic Cysts

Cystic pancreatic lesions are increasingly diagnosed owing to the abundant use of cross-sectional imaging. Given their malignant potential, true pancreatic cysts should be considered for resection or periodic follow-up. Cystic lesions of the pancreas (CLPs) require further evaluation and management. Therefore, it is important to establish a solid diagnosis at the time of detection. Endoscopic ultrasound examination is the imaging modality of choice. Fine needle aspiration provides fluid for cytologic, biochemical, and molecular assays to classify lesions and predict biological behavior. This review provides an overview of the diagnosis and management of various types of commonly encountered true CLPs.

EUS Morphology Is Reliable in Selecting Patients with Mucinous Pancreatic Cyst(s) Most Likely to Benefit from Surgical Resection

Background and Study Aims

Endoscopic ultrasound (EUS) surveillance of patients with mucinous pancreatic cysts relies on the assessment of morphologic features suggestive of malignant transformation. These criteria were derived from the evaluation of surgical pathology in patients with pancreatic cysts who underwent surgery. Reliability of these criteria when evaluated by EUS in identifying lesions which require surgery has still not been established.

Patients and Methods

This retrospective cohort study included seventy-eight patients who underwent surgical resection of pancreatic cysts based on EUS-FNA (fine-needle aspiration) findings suggestive of mucinous pancreatic cysts with concern for malignancy.

Results

Final surgical pathology diagnoses of patients were the following: adenocarcinoma (19), intraductal papillary mucinous neoplasm (IPMN) (39), mucinous cystic neoplasm (MCN) (13), serous cystadenoma (2), pseudocyst (3), mucinous solid-cystic lesion of indeterminate type (1), and mesenteric cyst (1). Cysts with focal wall thickening ≥ 3 mm (p = 0.0008), dilation of pancreatic duct (PD) (p = 0.0067), and cyst size ≥ 3 cm (p = 0.016) had significantly higher risk of adenocarcinoma. None of the patients without any of these morphologic features had cancer.

Conclusions

In patients with mucinous pancreatic cyst(s), focal wall thickening, cyst size ≥ 3 cm, and PD dilation as assessed by EUS can help identify advanced mucinous cysts which require surgery and should routinely be evaluated during EUS surveillance.

Natural History of Pancreatic Cysts

Pancreatic cystic neoplasms are discovered with increasing frequency. Accurate knowledge of the natural history of cystic neoplasms is crucial to develop useful and cost-effective strategies for surveillance and surgical resection. To date, the natural history of cystic neoplasms is still incomplete due to lack of adequate diagnostic accuracy in the absence of surgical pathology. Nevertheless, current evidence points to risk factors for malignant transformation to help clinical management. New biomarkers that accurately distinguish cyst neoplasms and those most likely to progress to cancer would help clarify the natural history of cystic neoplasms.

Endoscopic ultrasonography evaluation for pancreatic cysts: Necessity or overkill?

Incidental pancreatic cysts have become gradually more recognized in clinical practice as a result of increased use of transabdominal ultrasound, computed tomography (CT) and magnetic resonance imaging (MRI). These lesions consist of inflammatory cysts (pseudocysts) and pancreatic cystic neoplasms (PCN) which have been classified as benign, premalignant and malignant. The diagnosis and management strategy of incidentally discovered pancreatic cysts can be challenging as the majority of them are PCN and CT or MRI alone may not be sufficient to provide an accurate diagnosis. Endoscopic ultrasound (EUS)-guided fine-needle aspiration provides a method to obtain cyst fluid for analysis and the recently developed EUS-based technology including contrast-enhanced ultrasound, cystoscopy and needle-based confocal laser endomicroscopy allows endosonographers to gain additional useful information. The current data suggest that EUS evaluation of pancreatic cysts offers some benefits especially in cases of inconclusive CT or MRI.

Moving beyond morphology: new insights into the characterization and management of cystic pancreatic lesions

The frequency of detection of cystic pancreatic lesions with cross-sectional imaging, particularly with multidetector computed tomography, magnetic resonance (MR) imaging, and MR cholangiopancreatography, is increasing, and many of these cystic pancreatic lesions are being detected incidentally in asymptomatic patients. Because there is considerable overlap in the cross-sectional imaging findings of cystic pancreatic lesions, and because many of these lesions being detected are smaller than 3 cm in diameter and lack any specific cross-sectional imaging features, it has become difficult to make informed decisions about patient management when the precise diagnosis remains uncertain. This article presents the limitations of cross-sectional imaging in patients with cystic pancreatic lesions, details advances in knowledge of the genomic and epigenomic changes that lead to progression of carcinogenesis, outlines the current understanding of the natural history of mucinous cystic lesions, and includes the current use and future potential of novel tumor markers and molecular analysis to characterize cystic pancreatic lesions more precisely. The need to move beyond cross-sectional imaging morphology and toward the use of new techniques to diagnose these lesions accurately is emphasized. An algorithm that uses these techniques is proposed and will hopefully lead to improved patient management.

Diagnostic yield of EUS-FNA-based cytology distinguishing malignant and benign IPMNs: a systematic review and meta-analysis

OBJECTIVES

Differential diagnosis of malignant and benign intraductal papillary mucinous neoplasms (IPMNs) is essential to determine the optimal treatment. Endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) is currently used to diagnose pancreatic cystic lesions worldwide, but few studies have focused on the diagnostic yield to distinguish malignant and benign IPMNs. Therefore, we aim to systematically review the diagnostic yield of EUS-FNA-based cytology to distinguish malignant and benign IPMNs.

METHODS

Relevant studies with a reference standard of definitive surgical histology which published between 2002 and 2012 were identified via MEDLINE and SCOPUS. Malignant IPMNs included invasive adenocarcinoma, carcinoma in situ, and high-grade dysplasia.

RESULTS

Four studies with 96 patients were included in this meta-analysis. For diagnostic yield of EUS-FNA-based cytology distinguishing malignant and benign IPMNs, the pooled sensitivity and specificity were 64.8% (95% CI, 0.44-0.82) and 90.6% (95% CI, 0.81-0.96), respectively. Similarly, the positive likelihood ratio and negative likelihood ratio were 6.35 (95% CI, 2.95-13.68) and 0.43 (95% CI, 0.14-1.34), respectively. Malignant IPMNs were observed in 20.8% (20/96) of patients in EUS-FNA studies.

CONCLUSIONS

EUS-FNA-based cytology has good specificity but poor sensitivity in differentiating benign from malignant IPMNs. Newer techniques or markers are needed to improve diagnostic yield.

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.

Pancreatic cystic lesions: The value of contrast-enhanced endoscopic ultrasound to influence the clinical pathway

Background and Objectives:

Cystic pancreatic lesions are a growing diagnostic challenge. The aim of this study was to proof a new diagnostic concept based on contrast-enhanced endoscopic ultrasound (CE-EUS) for differential diagnosis.

Patients and Methods:

A total of 125 patients with unclear cystic pancreatic lesions were included. The initial diagnostic was made by CE-EUS dividing the lesions in a group without contrast enhancing effect in the cystic wall, septae or nodule indicating pseudocysts or dysontogenetic cysts and a group with contrast enhancing effect in the described structures indicating cystic neoplasias. The investigations were performed using a Pentax echoendoscope and Hitachi Preirus ultrasound machine. The contrast enhancer used was 4.8 mL SonoVue^® (Bracco, Italy). The group with suspected cystic neoplasia was referred for endoscopic fine-needle puncture for further diagnostic or treatment decisions.

Results:

The dividing of the groups by contrast-enhanced ultrasound was feasible because all (n = 56) suspected cystic neoplasias showed a contrast enhancing effect, whereas in only 4 from 69 pseudocystic or dysontogenetic cystic lesions a contrast enhancing effect in the wall could be observed. Endoscopic fine-needle puncture could diagnose all malignant neoplasias and relevant premalignant conditions. The long-term follow-up did not show any development of malignant cystic lesions.

Conclusion:

Using CE-EUS and endoscopic fine-needle puncture as diagnostic criteria seemed to be a feasible method to deal with different cystic lesions in daily practice.

Impact of endoscopic ultrasound-guided fine-needle aspiration on incidental pancreatic cysts. A prospective study

OBJECTIVE

Widespread use of imaging procedures has promoted a higher identification of incidental pancreatic cysts (IPCs). However, little is known as to whether endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) could change the management strategy of patients having IPCs. This study has aimed to evaluate the management impact of EUS-FNA on IPCs.

MATERIAL AND METHODS

Patients with pancreatic cysts (PCs) who were referred to EUS-FNA were recruited prospectively. The referring physicians were questioned about the management strategy for these patients before and after EUS-FNA. The impact of EUS-FNA on management was then evaluated.

RESULTS

A total of 302 PC patients were recruited. Of these, 159 (52.6%) patients had asymptomatic IPCs. The average size was 2.3 cm (range: 0.2-7.1 cm), and 110 patients having smaller than 3 cm sized cysts. Lesions were located in the pancreatic head in 96 (61%) cases, and most patients (94%) had only a single cyst. The final diagnoses, obtained by EUS-FNA (91) and surgery (68), were 93 (58%) benign lesions, 36 (23%) cysts with malignant potential, 14 (9%) noninvasive malignancies, 10 (6%) malignant precursor lesions (PanIN), and 6 (4%) invasive malignancies. Management strategy changed significantly after EUS-FNA in 114 (71.7%) patients: 43% of the cases were referred to surgery, 44% of the patients were discharged from surveillance, and 13% of the cases were given further periodical imaging tests.

CONCLUSION

EUS-FNA has a management impact in almost 72% of IPCs, with a major influence on the management strategy, either discharge rather than surgical resection or surgery rather than additional follow up.

Performance characteristics of molecular (DNA) analysis for the diagnosis of mucinous pancreatic cysts

BACKGROUND

Diagnosis of mucinous pancreatic cysts (MPCs) is challenging due to the poor sensitivity of cytology provided by EUS-guided-FNA (EUS-FNA).

OBJECTIVE

To quantify the test characteristics of molecular (DNA) analysis in suspected low-risk MPCs.

DESIGN

A prospective cohort study performed in between 2008 and 2011.

SETTING

Academic referral center.

PATIENTS

Consecutive patients who underwent EUS-FNA of suspected MPCs.

INTERVENTION

EUS-FNA and molecular (DNA) analysis of cyst fluid.

MAIN OUTCOME MEASUREMENTS

The sensitivity and specificity of molecular analysis in the diagnosis of MPCs using the criterion standard of surgical pathology in resected cysts.

RESULTS

Patients with suspected MPCs underwent EUS-FNA and cyst fluid DNA analysis. Surgical resection was performed in 48 patients (17%), confirming a mucinous pathology in 38 (79%). In this group, molecular analysis had a sensitivity of 50% and a specificity of 80% in identifying MPCs (accuracy of 56.3%). The combination of molecular analysis with cyst fluid carcinoembryonic antigen (CEA) and cytology resulted in higher MPC diagnostic performance than either one of its individual components, with a sensitivity, specificity, and accuracy of 73.7%, 70%, and 72.9%, respectively. There was no significant difference in accuracy between molecular analysis and CEA/cytology in this group.

LIMITATIONS

Single-center experience.

CONCLUSION

Molecular analysis aids in the diagnosis of MPCs when cytology is nondiagnostic or cyst fluid is insufficient for CEA or its level is indeterminate. Our results do not support the routine use of molecular analysis, which should be used selectively after review of imaging findings and cyst fluid studies. Further studies are needed to assess DNA's performance in malignant cysts.

Pancreatic cystic neoplasms: management and unanswered questions

Approximately 10% of persons 70 years old or older are now diagnosed with pancreatic cysts, but it is not clear which ones require additional analysis, interventions, or follow-up. Primary care doctors rely on gastroenterologists for direction because no one wants to miss a diagnosis of pancreatic cancer, but meanwhile there is pressure to limit use of diagnostic tests and limit costs. We review the different cystic neoplasms of the pancreas and diagnostic strategies based on clinical features and imaging data. We discuss surgical and nonsurgical management of the most common cystic neoplasms, based on the recently revised Sendai guidelines. Intraductal papillary mucinous neoplasm (particularly the branch duct variant) is the lesion most frequently identified incidentally. We report what is known about its pathology, its risk of developing into pancreatic ductal adenocarcinoma, the pros and cons of current guidelines for management, and the potential role of endoscopic ultrasound in determining cancer risk. We also review surgical treatment and strategies for surveillance of pancreatic cysts.

Clinical decision making in the management of pancreatic cystic neoplasms

Pancreatic cystic lesions continue to pose diagnostic and management dilemmas for physicians. This may be related, in part, to the fact that these lesions represent a range of diagnostic possibilities, from inflammatory cysts and nonmucinous cysts to mucinous cysts, which may or may not have foci of invasive malignancy. Adequate characterization of cystic lesions is necessary to help devise a management plan. Moreover, patient-related factors such as comorbid conditions are often essential in deciding whether patients should be managed by a conservative approach of watchful waiting versus surgical resection, if so indicated. This review summarizes the recent advances in the management of pancreatic cystic neoplasms.

Cystic and ductal tumors of the pancreas: diagnosis and management

Incidentally discovered cystic tumors of the pancreas (CTP) are an increasingly frequent entity. It is essential to differentiate lesions whose malignant potential is either nil or negligible (pseudocyst, serous cystadenoma, simple cysts) from lesions with intermediate malignant potential (intraductal papillary mucinous tumor of the pancreas [IPMN] involving the secondary ducts, cystic endocrine tumor) or those with high malignant potential (mucinous cystadenoma, solid pseudopapillary tumors and IPMN involving the main pancreatic duct). The approach to defining malignant potential is based on diagnostic CT scan, magnetic resonance imaging (MRI), and endoscopic ultrasound (EUS), often complemented by EUS-guided cyst puncture for biochemical and cytological analysis of cyst fluid. Surgery for diagnostic purposes should be avoided because of its significant morbidity. For pseudocysts, simple cysts and serous cystadenomas, abstention is the general rule. Resection, preserving as much pancreatic parenchyma as possible, is the rule for IPMN involving the main pancreatic duct, mucinous cystadenomas, solid and pseudopapillary tumors, and cystic endocrine tumors. Resection is rarely indicated at the outset for IPMN involving secondary pancreatic ducts; morphologic observation is the general rule and preventive excision may be indicated secondarily. Good collaboration between surgeons, radiologists and endosonographists is necessary for optimal management of CTP.

Natural history of asymptomatic pancreatic cystic neoplasms

BACKGROUND

The management of asymptomatic pancreatic cysts is controversial and indications for excision are based on pathology and natural history.

OBJECTIVES

This study aimed to examine outcomes of asymptomatic lesions using a protocol based on size and cyst fluid analysis.

METHODS

Asymptomatic cysts were identified from a prospectively maintained database. Sequential cross-sectional imaging studies were assessed, and results of endoscopic ultrasound-guided aspiration were co-analysed.

RESULTS

A total of 338 asymptomatic patients underwent evaluation. Overall, 84 cysts were <1.5 cm and 254 were ≥1.5 cm in diameter. Median patient follow-up was 5.1 years [interquartile range (IQR): 4.1-6.9 years]. In the group in which cysts measured <1.5 cm in diameter, median cyst size was 1.0 cm (IQR: 0.6-1.2 cm) at presentation and increased to 1.2 cm (IQR: 0.7-1.6 cm) during follow-up. Five (6.0%) patients underwent resection, all within 2 months of presentation. In the group in which cysts measured ≥1.5 cm in diameter, median cyst size was 2.5 cm (IQR: 2.0-3.4 cm) at presentation and increased to 2.7 cm (IQR: 3.0-4.2 cm). A total of 63 (24.8%) patients underwent resection. Surgery was performed with 2 months in 53 (84.1%) patients, within 12 months in four (6.3%) patients and at >12 months post-presentation in six (9.5%) patients. A total of 70.6% of resected specimens were identified as malignancies or mucinous lesions.

CONCLUSIONS

Asymptomatic cysts of <1.5 cm in diameter can safely be followed by imaging and are expected to undergo little change. A quarter of all asymptomatic cysts measuring ≥1.5 cm are appropriately resected based on imaging and cyst fluid analysis.

Accuracy of preoperative workup in a prospective series of surgically resected cystic pancreatic lesions

BACKGROUND

Magnetic resonance imaging (MRI) and endoscopic ultrasound (EUS) are considered useful techniques in the evaluation of pancreatic cysts. Aim of this study was to prospectively compare the diagnostic value of these techniques.

METHODS

This study included consecutive patients who underwent MRI, EUS, and EUS-FNA for a pancreatic cyst that was eventually resected surgically. Observers scored for cyst characteristics, a distinction between mucinous and non-mucinous cysts and a suspicion of malignancy. The interobserver agreement between MRI and EUS was calculated.

RESULTS

A total of 32 patients were included. Sensitivity for diagnosing a mucinous cyst was 78% for EUS versus 91% for MRI. Sensitivity for detecting malignancy was 25% (1/4) and 50% (2/4) for EUS and MRI respectively. Sensitivity of EUS-FNA for diagnosing a mucinous cyst (positive cytology and/or CEA >192 ng/ml) was 61%. Sensitivity for detecting malignancy (positive cytology) was 1/4 (25%). Interobserver agreement between MRI and EUS for the features was poor to fair.

CONCLUSION

MRI and EUS are comparable techniques for the morphological characterization of pancreatic cysts. Combined sensitivity of EUS and MRI was higher than the sensitivity of one of the techniques alone. For diagnosing a mucinous cyst, FNA findings showed a low sensitivity, but a high specificity.

Long-term outcome of cystic lesions in the pancreas: a retrospective cohort study

Background/Aims

The management guidelines for cystic lesions of the pancreas (CLPs) are not yet well established. This study was performed to document the long-term clinical outcome of CLPs and provide guidelines for the management and surveillance of CLPs.

Methods

In this retrospective cohort study, an additional follow-up was performed in 112 patients with CLPs enrolled from 1998 to 2004 during a previous study.

Results

During follow-up for the median period of 72.3 months, the size of the CLPs increased in 18 patients (16.1%). Six of these patients experienced growth of their CLPs after 5 years of follow-up. Twenty-six patients underwent surgery during follow-up, and four malignant cysts were detected. The overall rate of malignant progression during follow-up was 3.6%. The presence of mural nodules or solid components was independently associated with the presence of malignant CLPs. Seven patients underwent surgery after 5 years of follow-up. The pathologic findings revealed malignancies in two patients. There was only one pancreas-related death during follow-up.

Conclusions

The majority of CLPs exhibit indolent behavior and are associated with a favorable prognosis. However, long-term surveillance for more than 5 years should be performed because of the potential for growth and malignant transformation in CLPs.

Endoscopic ultrasound-guided pancreatic cyst ablation

Pancreatic cystic neoplasms represent a wide spectrum of invariably benign to precancerous and malignant tumors. Endoscopic ultrasound-guided pancreatic cyst ablation with ethanol and/or paclitaxel offers a nonoperative treatment for patients refusing or not eligible for surgery. Histopathology after resection in these patients has shown variable degrees of cyst epithelial ablation ranging from 0% to 100%. Future research investigating the safety of this procedure, modifications of reported ablation techniques, choice and number of the lavage agents used, and criteria to optimize selection of the appropriate pancreatic cysts for treatment is needed.

Diagnosis and treatment of cystic pancreatic tumors

Cystic pancreatic tumors (CPTs) have more frequently been identified in the last decade because of increased use of cross-sectional abdominal imaging. Although serous CPTs follow an indolent course and do not necessarily require surgical resection or long-term follow-up, mucinous CPTs (mucinous cystic neoplasms and intraductal papillary mucinous neoplasms) have a greater risk for malignancy. Although most CPTs are initially detected with imaging modalities such as computed tomography or magnetic resonance imaging, these tests alone rarely permit an accurate clinical diagnosis. Endoscopic ultrasound and endoscopic ultrasound-guided, fine-needle aspiration allow real-time examination and biopsy analysis of CPTs, which increases diagnostic accuracy because cytopathology features and tumor markers in cyst fluid can be analyzed. Management of patients with mucinous CPTs by surgery or imaging surveillance is controversial, partially because of limited information about disease progression and the complexities of surgical resection. We review approaches to diagnosis and management of common CPTs.

EUS-FNA for pancreatic cyst lesion, today and tomorrow in the Kingdom of Thailand

Unlike endoscopic retrograde cholangiopancreatography (ERCP) service, endoscopic ultrasonography (EUS) service in Thailand is at its elementary state. Currently, there are only 11 hospitals in Thailand carrying out EUS whereas there are more than 50 hospitals carrying out ERCP. This is a multicenter questionnaire survey that obtained information on EUS practice for pancreatic cysts. Of those 11 hospitals, only three hospitals provided enough number of patients with pancreatic cysts undergoing EUS. There were many differences in endosonographers opinions regarding specific information in the pancreatic cyst. In addition, the threshold to carry out and not to carry out fine needle aspiration are varies.

Pancreatic cystic lesions: when to watch, when to operate, and when to ignore

Pancreatic cystic lesions are being increasingly identified with the widespread use of state-of-the-art imaging. These lesions are categorized into a broad range of neoplastic cysts and inflammatory pseudocysts. Identification of a pancreatic cyst requires the clinician to focus on the main clinical challenge of the benign or malignant nature of the cyst. Neoplastic cysts range the spectrum from benign, to premalignant, to frank malignancy. The management of these lesions is difficult, and the decision to resect or observe a lesion is hampered by limitations in current imaging and tissue sampling techniques that prevent the accurate characterization of all lesions. This article reviews current guidelines for the evaluation of pancreatic cystic lesions, underscores the challenges posed by these lesions, and discusses current and future studies that will aid in patient management.

Pancreatic cystic lesions

PURPOSE OF REVIEW

Pancreatic cystic neoplasms are increasingly identified and their management remains uncertain. Recent studies demonstrate an evolving clinical approach.

RECENT FINDINGS

The vast majority of asymptomatic pancreatic cysts without concerning clinical or imaging features can be observed without surgery. Clinical predictors for malignancy at surgery include male sex, age above 50 years, weight loss, and high cyst fluid carcinoembryonic antigen (CEA), but these factors are insufficient for patient selection. Endoscopic ultrasound (EUS)-guided fine needle aspiration with cyst fluid analysis for risk stratification and selective resection appears the most cost-effective approach. In addition to CEA, DNA analysis, differential protein expression, and proteomic studies of cyst fluid may be helpful in differentiating cystic lesions in selected patients. EUS-guided ethanol lavage of cysts resulted in regression; this method may have a role in treatment in the future. More future research investigating the safety of this procedure, technique modifications, and choice of agent is needed.

SUMMARY

The approach to incidentally discover pancreatic cystic lesions is challenging due to the difficulty in preoperative definitive lesion characterization. Recently developed diagnostic and treatment strategies show promise for improved patient outcomes.

Pancreatic cyst aspiration analysis for cystic neoplasms: mucin or carcinoembryonic antigen--which is better?

BACKGROUND

Differentiation between the various pathologies presenting as a cystic pancreatic lesion is clinically important but often challenging. We have previously advocated the performance of endoscopic ultrasound (EUS) with aspiration and determination of mucin and carcinoembryonic antigen (CEA) content. We sought to report the results of this ongoing protocol and determine the relative importance of cyst fluid mucin and CEA for the diagnostic process.

METHODS

The institutions prospectively maintained pancreatic cyst database was accessed to identify patients who had undergone pancreatic EUS and cyst aspiration as part of their evaluation. Only those patients who had subsequently undergone resection were selected, with histopathology being the gold standard for comparison.

RESULTS

From January 2000 to July 2009, 174 patients with pancreatic cystic disease underwent surgery, 121 of whom had an EUS with aspiration attempted at our institution with specimens sent for mucin and CEA. Based on histopathology, 86 mucinous lesions were identified, including 44 cystadenomas, 34 intraductal papillary mucinous neoplasms, 7 mucinous adenocarcinomas, and 1 intraductal oncocytic papillary neoplasm; 42 were nonmucinous lesions. The median cyst CEA levels were significantly higher in the mucinous lesions group at 850 versus 2 ng/mL (P = .001). The sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), positive diagnostic likelihood ratio, and negative diagnostic likelihood ratio (NDLR) were calculated respectively for mucin alone (0.80, 0.40, 0.61, 0.63, 1.33, 0.68); CEA alone (0.93, 0.43, 0.51, 0.91, 1.63, 0.16); cytology alone (0.38, 0.9, 0.92, 0.31, 3.67, 0.69); mucin or CEA (0.83, 0.65, 0.87, 0.57, 2.51, 0.26); mucin or CEA or cytology (0.92, 0.52, 0.86, 0.68, 1.91, 0.15); mucin plus CEA (0.96, 0.34, 0.25, 0.97, 1.45, 0.12); mucin plus cytology (0.25, 0.97, 0.96, 0.29,7.25, 0.78); CEA plus cytology (0.12, 1.00, 1.00, 0.26, ∞, 0.88); and mucin plus CEA plus cytology (0.08, 1.00, 1.00, 0.25, ∞, 0.92).

CONCLUSION

Assessment of cyst mucin and CEA are complementary, with the best profile obtained when both markers are determined along with cytology. This combination provides a good sensitivity, PPV, and NDLR, as well as reasonable PPV and PDNR.