Validation of international consensus guidelines for the resection of branch duct-type intraductal papillary mucinous neoplasms

Management of Incidental Pancreatic Cystic Lesions

BACKGROUND

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

METHODS

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

RESULTS

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

CONCLUSION

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

Natural History and Management of Intraductal Papillary Mucinous Neoplasms: Current Evidence

Background

With the use of modern cross-sectional abdominal imaging modalities, an increasing number of cystic pancreatic lesions are identified incidentally. Although there is no pathological diagnosis available in most cases, it is believed that the majority of these lesions display small branch-duct intraductal papillary mucinous neoplasms (BD-IPMNs) of the pancreas. Even though a number of large clinical series have been published, many uncertainties remain with regard to this entity of mucinous cystic neoplasms.

Methods

Systematic literature review.

Results

Main-duct (MD) and mixed-type IPMNs harbor a high risk of malignant transformation. It is conceivable that most IPMNs with involvement of the main duct tend to progress to invasive carcinoma over time. Thus, formal oncologic resection is the treatment of choice in surgically fit patients. In contrast, the data regarding BD-IPMN remain equivocal, resulting in conflicting concepts. To date, it is not clear whether and which BD-IPMNs progress to carcinoma and how long this progression takes.

Conclusion

While patients with MD-IPMNs should undergo surgical resection if comorbidities and life expectancy permit this, the management of small BD-IPMNs remains controversial. Population-based studies with long-term follow-up are needed to define which cohort of patients can be observed safely without immediate resection.

Clinical implication of serum carcinoembryonic antigen and carbohydrate antigen 19-9 for the prediction of malignancy in intraductal papillary mucinous neoplasm of pancreas

BACKGROUND

Little is known about the prognostic significance of serum carbohydrate antigen (CA) 19-9 and carcinoembryonic antigen (CEA) concentrations for predicting malignancy in patients with intraductal papillary mucinous neoplasm (IPMN) of pancreas.

METHOD

The study cohort consisted of 367 patients with surgical biopsy proven IPMN at Seoul National University Hospital. Preoperative serum tumor markers were evaluated and compared with other clinical variables.

RESULTS

Malignant pathology (high grade dysplasia [HGD] and invasive IPMN) was identified in 117 (31.9%) patients. Elevated serum CA19-9 was more frequent in patients with malignant (34.2%, P < 0.001; invasive IPMN vs. HGD 47.9% vs. 11.4%, P < 0.001) and main duct type (40.0%, P = 0.003) IPMN. Multivariate analysis showed main pancreatic duct (MPD) >5 mm (P < 0.001), mural nodules (P < 0.001), and elevated serum CA19-9 (P < 0.001) were independent predictors of malignancy. The sensitivity, specificity and accuracy were 34.2%, 92.4%, and 73.8%, respectively, for elevated serum CA19-9; 63.3%, 78.0%, and 73.3%, for MPD >5 mm; and 59.0%, 86.4%, and 77.7%, for mural nodules.

CONCLUSION

Serum CA19-9 is significantly higher in patients with malignant IPMN, especially in patients with invasive and main duct type IPMN. The diagnostic power of serum CA19-9 in predicting malignancy is comparable to that of MPD >5 mm and mural nodules.

Serum N-glycan profiles in patients with intraductal papillary mucinous neoplasms of the pancreas

BACKGROUND/OBJECTIVES

Diagnosing the invasiveness of intraductal papillary mucinous neoplasms (IPMNs) is difficult, especially by blood test. Alterations in serum glycan profiles have been reported for several cancers, but changes in serum glycan profiles have not been investigated in patients with IPMNs. The objectives of this study were to determine the serum N-glycan profile and to investigate its clinical utility in patients with IPMNs.

METHODS

We measured serum N-glycan profiles in 79 patients with IPMNs, including 13 invasive IPMNs, by performing comprehensive glycome analysis and assessed the relationship between N-glycan changes and clinical parameters.

RESULTS

Seventy glycans were identified and their expression profiles were significantly different depending on the cyst size, the presence of an enhancing solid component, and the histological grade of the IPMN. Nine glycans were highly expressed in patients with invasive IPMNs. The glycan m/z 3195, which is a fucosylated tri-antennary glycan, had the highest diagnostic value for distinguishing invasive IPMNs from non-invasive IPMNs (area under the receiver operating characteristic curve = 0.803). Multivariate analyses revealed high levels of m/z 3195 [odds ratio (OR), 20.5; 95% confidence interval (CI) 2.60-486.4] and the presence of enhancing solid components (OR, 35.8; 95% CI, 5.39-409.6) were significant risk factors for invasive IPMNs.

CONCLUSIONS

We performed a comprehensive evaluation of the changes in serum N-glycan profiles in patients with IPMNs for the first time. We determined that increased expression of fucosylated complex-type glycans, especially m/z 3195, is a potential marker for invasive IPMNs.

Risk factors for malignant progression of intraductal papillary mucinous neoplasms

BACKGROUND

Intraductal papillary mucinous neoplasms of the pancreas are increasingly diagnosed. Due to their malignant potential, greater understanding of their nature is required.

AIMS

Define risk factors for malignancy in intraductal papillary mucinous neoplasms.

METHODS

An international, multicentre study was performed in Europe and the United States. Clinical databases were reviewed for patients with intraductal papillary mucinous neoplasms diagnosis.

RESULTS

Of 1126 patients, 84 were diagnosed with invasive carcinoma/high-grade dysplasia and were compared to the rest of the cohort. Multivariate logistic analysis showed a statistically significant association between cancer/high-grade dysplasia and the variables smoking history (OR 1.9, 95% CI [1.1-3.1]), body mass index (OR 1.1, 95% CI [1-1.1]), symptoms (OR 3.4, 95% CI [1.9-6]), jaundice (OR 0.1, 95% CI [0-0.3]), and steatorrhea (OR 0.3, 95% CI [0.1-0.8]). Univariate analysis showed no association between malignancy and the cyst number/location (p=0.3 and p=0.5, respectively) although a strong association was shown for cyst size (p<0.001). The presence and size of nodules (p<0.01) and main duct involvement (p<0.001) were also strongly related with malignancy.

CONCLUSION

The presence of jaundice and steatorrhea, smoking, high body mass index, and imaging features such as cyst size, main duct involvement, and the presence and size of mural nodules are associated with high-grade neoplasia in intraductal papillary mucinous neoplasms.

Does PET with CT Have Clinical Utility in the Management of Patients with Intraductal Papillary Mucinous Neoplasm?

BACKGROUND

Intraductal papillary mucinous neoplasms (IPMNs) are well-established pancreatic precancerous lesions. Indications for resection are outlined in the 2012 International Consensus Guidelines (ICG). Because of the low specificity of the ICG, many patients will undergo potentially unnecessary surgery for nonmalignant IPMNs. Several retrospective studies have reported that positron emission tomography (PET) with CT (PET/CT) is highly sensitive and specific in detecting malignant IPMNs. We hypothesized that PET/CT complements the ICG in identification of malignant IPMNs.

STUDY DESIGN

From 2009 to 2013, patients with a suspected clinical or cytopathologic diagnosis of IPMN were prospectively enrolled in a clinical trial at a single center. Results of preoperative PET/CT on determination of IPMN malignancy (ie, high-grade dysplastic and invasive) was compared with surgical pathology. PET/CT uptake was considered increased if the standardized uptake value was ≥3.

RESULTS

Of the 67 patients enrolled, 50 patients met all inclusion criteria. Increased PET/CT uptake was associated with significantly more malignant and invasive IPMNs (80% vs 13%; p < 0.0001 and 40% vs 3%; p = 0.004). When patients were divided into branch duct and main duct IPMNs, increased PET/CT uptake was also associated with more malignancy (60% vs 0%; p = 0.006 for branch duct IPMN and 100% vs 23%; p = 0.003 for main duct IPMN). Patients with ICG criteria (eg, worrisome features and high-risk stigmata) and increased PET/CT uptake had more malignant and invasive IPMNs than patients with ICG criteria, but no increased uptake (78% vs 17%; p = 0.001 and 33% vs 3%; p = 0.03). The sensitivity and specificity of the ICG criteria for detecting malignancy were 92% and 27%, respectively, and PET/CT was less sensitive (62%) but more specific (95%). When PET/CT was added to ICG criteria, the association resulted in 78% sensitivity and 100% specificity.

CONCLUSIONS

The addition of PET/CT to preoperative workup improves the performance of the ICG for predicting malignant risk in patients with IPMN.

Surgical outcomes of multifocal branch duct intraductal papillary mucinous neoplasms of pancreas

Backgrounds/Aims

Appropriate management for multifocal branch duct type intraductal papillary mucinous neoplasms (BD-IPMNs) of the pancreas is still controversial. This study was intended to reveal surgical outcomes of surgical resection for multifocal BD-IPMNs, with BD-IPMNs in the remnant pancreas.

Methods

Between January 1995 and December 2013, 699 patients underwent the pancreatic resection due to IPMN of pancreas in our institution. Among them, 37 patients showed multifocal BD-IPMNs. After excluding patients who had BD-IPMNs completely resected, medical records of 22 patients with remained BD-IPMNs in the remnant pancreas were retrospectively reviewed.

Results

Mean patient age was 65±6.4 years. Types of surgery included central pancreatectomy (n=1), distal pancreatectomy (n=14), and standard pylorus-preserving pancreaticoduodenectomy (n=7). Specimen pathology showed that IPMN was either at low/intermediate-grade dysplasia (n=17) or at high-grade dysplasia (n=2). Three patients had IPMN associated with invasive carcinoma. Their mean follow-up period was 40.4 months. During follow-up, one mortality occurred 35.2 months after the operation which was not associated with IPMN. There was no clinically significant disease progression or recurrence of IPMN in the remnant pancreas during the follow-up period.

Conclusions

Our results support that we can safely preserve the pancreas parenchyma with multifocal BD-IPMNs. Benign-looking multifocal BD-IPMNs in the remnant pancreas do not affect the survival of patients.

Diagnostic approach to pancreatic cysts

PURPOSE OF REVIEW

Diagnosis of pancreatic cysts remains challenging due to limitations of currently available radiologic and endoscopic tools. The diagnostic approach should focus on identifying mucinous and malignant cysts. Mucinous cysts require further differentiation to allow appropriate management.

RECENT FINDINGS

Although the overall rate of malignant pancreatic cysts is low, it remains higher than the general population. MRI with magnetic resonance cholangiopancreatography is the preferred imaging modality for pancreatic cysts. Attempts to improve diagnostic yield of endoscopic ultrasound-guided fine needle aspiration include performing cyst wall cytology and DNA analysis. The 2012 international consensus guidelines for mucinous cystic neoplasm and intraductal papillary mucinous neoplasm are superior to the original 2006 guidelines, although issues include the relatively poor ability to diagnose malignant cysts leading to unnecessary surgeries and the de-emphasis of cyst size. Cyst size remains an important predictor of malignancy. Translational research involving genomics, microRNA, proteomics, and metabolomics holds promise for improved biomarkers. Endoscopic innovations may safely aid in cyst diagnosis.

SUMMARY

Incremental improvements in pancreatic cyst diagnosis have occurred with new biomarkers and endoscopic tools requiring validation in large-scale studies.

Incidental Cystic Lesions in the Pancreas: Resect? EUS? Follow?

Pancreatic cysts challenge clinicians due to their increased incidental identification on radiology imaging, the limitations of currently available diagnostic tools, and potential for malignancy. Following initial identification of an incidental pancreatic cyst, a dedicated pancreatic protocol abdominal CT scan or MRI pancreas with MRCP should be performed. Surgical resection is recommended for all surgical candidates with MD-IPMN, mixed or combined type IPMN, mucinous cystic neoplasm, and solid pseudopapillary neoplasm. Serous cystadenoma may be followed with serial imaging unless the patient develops symptoms, the cyst is larger than 4 cm or rapidly growing, or diagnostic uncertainty remains despite thorough evaluation. Surveillance is also recommended for BD-IPMN without the following features concerning malignancy: obstructive jaundice with a cyst in the head of the pancreas; solid component; nodule; main pancreatic duct ≥10 mm; or cytology suspected or positive for malignancy. BD-IPMN ≥3 cm without concerning features may also be followed carefully, although surgical resection should be considered in surgically fit patients. EUS-FNA for cyst wall cytology, CEA, amylase, and occasionally k-ras mutation are also likely aids in the diagnosis of pancreatic cysts beyond radiologic imaging. This author typically recommends EUS-FNA to further evaluate cysts larger than 1 cm without definitive indication for resection. EUS is also appropriate in patients with solid component, nodule, or size ≥3 cm to aid in decision making, especially in older patients who may be less suitable surgical candidates. A multidisciplinary approach with a team of dedicated gastrointestinal radiologists, pancreatic surgeons, gastrointestinal pathologists, and gastroenterologists is essential for managing patients with pancreatic cysts.