Cystic neoplasms of the pancreas; What a clinician should know

The clinical impact of endoscopic ultrasound-guided fine-needle aspiration on the patients with low-risk pancreatic cystic lesions

Background and aims

Endoscopic ultrasound (EUS) is playing a more and more important role in the management of pancreatic cystic lesion (PCLs). The aim of our study was to evaluate the clinical impact of EUS and EUS guided fine needle aspiration (FNA) on patients with low-risk PCLs.

Materials and methods

Low-risk PCL patients who underwent EUS-FNA in 2 edoscopic centers were retrospectively collected and analyzed. The clinical impact of EUS-FNA on these patients was analyzed and the predictors for significance EUS-FNA (defined by diagnosis and treatment method change, new high-risk feature identified after imaging scans) were analyzed by logistic regression analyses.

Results

From July 2004 to February 2017, 186 patients with low-risk PCLs were included. The study cohort had a mean age of 52.4 ± 15.9 years (range: 19-86 years) with 89 (47.8%) male patients included. The clinical significance of EUS-FNAs was observed in 74 patients (39.8%). The presumed diagnoses of PCLs by imaging were changed in 51 (51/74, 68.9%) patients. Nineteen (19/74, 25.7%) new high-risk features were identified by EUS-FNA, and four patients (4/74, 5.4%) underwent surgery due to suspicious or malignant cytology. Based on multivariate analysis, large cyst size [odds ratio (OR): 1.12, 95% confidence interval (CI): 1.02–1.19, P = 0.033], young age (OR: 0.94, 95% CI: 0.91–0.99, P = 0.041) and BMI over 25 (OR: 3.15, 95% CI: 1.29–7.86, P = 0.013) were independent predictors of clinical significance for EUS-FNA. The optimal age and cyst size to predict significance EUS-FNA was 46.0 years and 2.3cm.

Conclusions

On the basis of a 2-center retrospective study, EUS-FNA was clinically significant in about 40% of low-risk PCLs, especially in young, large cyst size, and overweight patients.

Differentiating benign from malignant pancreatic cysts on computed tomography

•

CT can distinguish between benign and premalignant or malignant pancreatic cysts.

•

Solid component and septation were the only CT features that could differentiate benign from malignant cysts.

•

Cyst wall enhancements on CT were more commonly observed in premalignant or malignant cysts than in benign cysts.

•

CT is a necessary diagnostic modality to preoperatively detect and characterize pancreatic lesions.

Purpose

It is important to identify features on computed tomography (CT) that can distinguish between benign and premalignant or malignant pancreatic cysts to avoid unnecessary surgeries. This study investigated the preoperative diagnostic evaluation of cystic pancreatic lesions to determine how advanced imaging and clinical factors should guide management.

Methods

In total, 53 patients with 27 benign and 26 premalignant or malignant cysts were enrolled. CT features of the cysts were compared using univariate and multivariate analyses.

Results

On univariate analysis, a solid component (p < 0.01), septation (p < 0.01), location (p < 0.01), border (p < 0.01), wall enhancement (p = 0.01), lesion margins (p < 0.01), pancreatic atrophy (p = 0.04), and a cystic wall (p < 0.01) were all significantly different between benign and premalignant or malignant cysts. On multivariate analysis, only a solid component (p < 0.01) and septation (p < 0.01) were significant.

Conclusion

A thin cystic wall, uniform homogeneity, a clear border, the presence of septation, pancreatic atrophy, and the absence of both wall enhancements and solid components were more frequently seen in benign cysts. A thick wall, lack of homogeneity, the presence of wall enhancements and solid components, absence of septation, only a small degree of pancreatic atrophy, and unclear borders were more frequent among premalignant or malignant cysts. The only CT features to differentiate benign from premalignant or malignant cysts were a solid component and septation.

The Role of Positron Emission Tomography in Clinical Management of Intraductal Papillary Mucinous Neoplasms of the Pancreas

Intraductal papillary mucinous neoplasms (IPMNs) of the pancreas represent a heterogeneous group of tumors, increasingly diagnosed in clinical practice. An early differential diagnosis between malignant and benign lesions is crucial to patient management and the choice of surgery or observation. The therapeutic approach is currently based on a patient’s clinical, biochemical, and morphological characteristics. The latest published International Consensus Guidelines (ICG) make no mention of the role of metabolic assessments of IPMNs. The aim of this study was to review the current literature, examining the role of 18-fluorodeoxyglucose (FDG) positron emission tomography (PET) in IPMN management. An extensive literature review was conducted according to the 2009 Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, and 10 articles were analyzed in detail, focusing on the value of PET as opposed to other standard imaging criteria. Data were retrieved on 419 patients. The 18-FDG-PET proved more sensitive, specific, and accurate than the ICG criteria in detecting malignant IPMNs (reaching 80%, 95%, and 87% vs. 67%, 58%, and 63%, respectively). Metabolic assessments may be used as an additional tool for the appropriate management of patients with doubtful imaging findings.

Prevalence of pancreatic cystic lesions detected by magnetic resonance imaging in the Chinese population

BACKGROUND AND AIM

Incidental pancreatic cystic lesions (PCLs) are being diagnosed more frequently. However, little is known about the prevalence of PCLs in the Chinese population. The aim of the study was to assess the crude prevalence of PCLs in individuals who underwent magnetic resonance imaging (MRI).

METHODS

Data from consecutive patients who underwent MRI without pancreatic indications were included. MRI images were reviewed for the presence of pancreatic cysts. The prevalence of PCLs and high-risk PCLs in different gender and age groups was calculated. To assess the crude prevalence, the prevalence and demographic data were standardized on the basis of Chinese national population data in 2017.

RESULTS

A total of 10 987 individuals were included (7344 men). Incidental PCLs were identified in 212 individual (128 men). The prevalence of PCLs was 1.93%, and PCLs were more often discovered in women (1.74% vs 2.31%, P = 0.043). Prevalence increased with age (r = 0.804, P < 0.001). The prevalence of high-risk PCLs was 0.12% (n = 13). Gender predominance and age distribution showed no difference between high-risk PCLs and low-risk PCLs (P = 0.234 and P = 0.855), but cysts located in the pancreatic head were more likely to develop into high-risk PCLs (P = 0.001). After data standardization, the crude prevalence of PCLs was 1.31%, and PCLs were more often discovered in women (1.11% vs 1.5%, P < 0.001). The crude prevalence of high-risk PCLs was 0.07%.

CONCLUSION

Pancreatic cystic lesions in the Chinese population are not rare. The prevalence of PCLs increased with age and is higher in the female population. The prevalence of high-risk PCLs should not be ignored.

Endoscopic Management of Pancreatic Cysts

Management of pancreatic cystic lesions relies on patients' clinical presentation, imaging, and endoscopic ultrasound. Current research in basic science, radiology, and endoscopy is evolving and making progress in this condition which is relatively common in the general population. This review focuses on the recent endoscopic ultrasound approaches to the diagnosis of these pancreatic disorders.

Pancreatic mucinous cystadenocarcinoma: Epidemiology and outcomes

BACKGROUND

Pancreatic mucinous cystadenocarcinoma is a rare malignancy. Our aim was to investigate the demographic, pathological characteristics, treatment modalities and survival of patients with mucinous cystadenocarcinoma via the National Cancer Institute's Surveillance Epidemiology and End Results (SEER) database analysis.

MATERIALS AND METHODS

This was a retrospective study of SEER database's records on patients with mucinous cystadenocarcinoma diagnosed from 1988 to 2012. Primary outcome measures were clinico-pathological characteristics, observed and disease-specific survival.

RESULTS

A total of 507 patients were identified. Median age at diagnosis was 67 years and most patients were female (68.4%). The tumors were mainly low grade (82.9%, grade I-II) and frequently localized (42.8%) in the body/tail of the pancreas (45.6%). According to Kaplan-Meier curves observed survival was 111 months (95%CI: 82.5, 139.5) vs 14 months (95% CI: 10.9, 17.1) vs 4 months (95%CI: 2.9, 5.1) for patients with localized, regional and distant disease, respectively. One-year disease-specific survival for patients with localized disease was 90.1%, vs. 56.7% for those with regional and 18.7% with distant tumor spread.

CONCLUSIONS

Mucinous cystadenocarcinomas tend to be low grade tumors, localized to the pancreatic body/tail. Surgery as the primary therapeutic intervention and tumor stage are independent predictors of disease-specific survival.

Current perspectives on pancreatic serous cystic neoplasms: Diagnosis, management and beyond

Pancreatic cystic neoplasms have been increasingly recognized recently. Comprising about 16% of all resected pancreatic cystic neoplasms, serous cystic neoplasms are uncommon benign lesions that are usually asymptomatic and found incidentally. Despite overall low risk of malignancy, these pancreatic cysts still generate anxiety, leading to intensive medical investigations with considerable financial cost to health care systems. This review discusses the general background of serous cystic neoplasms, including epidemiology and clinical characteristics, and provides an updated overview of diagnostic approaches based on clinical features, relevant imaging studies and new findings that are being discovered pertaining to diagnostic evaluation. We also concisely discuss and propose management strategies for better quality of life.

Clinical importance of Familial Pancreatic Cancer Registry in Japan: a report from kick-off meeting at International Symposium on Pancreas Cancer 2012

Pancreatic cancer is still a highly lethal disease with a 5-year survival rate of approximately 5 %. Early detection offers one of the best hopes for improving survival. Previous cohort studies and case-control studies showed that 4-10 % of pancreatic cancers have a hereditary basis, and individuals with a family history have an increased risk of developing pancreatic and extra-pancreatic malignancies. Since individuals with a family history of pancreatic cancer and those with a known genetic syndrome that predisposes to pancreatic cancer will be the first to benefit from early detection tests as they become available, familial pancreatic cancer (FPC) registries have been established in the US and Europe, but not yet in Japan. Such registries form the basis for epidemiological studies, clinical trials, and basic research on familial pancreatic cancer. There is a need for FPC registries in Japan as cancer risk varies among different populations and discoveries made in Western populations may not translate to the Japanese population. These registries in Japan will align with ongoing international efforts and add to a better understanding of the natural history, risk factors, screening strategies, and responsible genes, for improving survival of this dismal disease.

Cyst Features and Risk of Malignancy in Intraductal Papillary Mucinous Neoplasms of the Pancreas: Imaging and Pathology

Background

Intraductal papillary mucinous neoplasms (IPMNs) display diverse macroscopic, histological, and immunohistochemical characteristics with typical morphological appearance in magnetic resonance imaging. Depending on those, IPMNs may show progression into invasive carcinomas with variable frequency. Overall, IPMN-associated invasive carcinomas are found in about 30% of all IPMNs, revealing phenotpyes comparable with conventional ductal adenocarcinomas or mucinous (colloid) carcinomas of the pancreas. In Sendai-negative side-branch IPMNs, however, the annual risk of the development of invasive cancer is 2%; thus, risk stratification with regard to imaging and preoperative biomarkers and cytology is mandatory.

Methods and Results

The present study addresses the radiological and interventional preoperative measures including histological features to determine the risk of malignancy and the prognosis of IPMNs.

Conclusion

While preoperative imaging largely relies on the detection of macroscopic features of IPMNs, which are associated with a divergent risk of malignant behavior, in resected specimens the determination of the grade of dysplasia and the detection of an invasive component are the most important features to estimate the prognosis of IPMNs.

Pancreatic cystic neoplasms: Review of current knowledge, diagnostic challenges, and management options

Pancreatic cystic lesions are being detected with increasing frequency, largely due to advances in cross-sectional imaging. The most common neoplasms include serous cystadenomas, mucinous cystic neoplasms, intraductal papillary mucinous neoplasms, solid pseudopapillary neoplasms, and cystic pancreatic endocrine neoplasms. Computed tomography (CT), magnetic resonance imaging (MRI), and endoscopic ultrasound (EUS) are currently used as imaging modalities. EUS-guided fine needle aspiration has proved to be a useful diagnostic tool, and enables an assessment of tumor markers, cytology, chemistries, and DNA analysis. Here, we review the current literature on pancreatic cystic neoplasms, including classification, diagnosis, treatment, and recommendations for surveillance. Data for this manuscript was acquired via searching the literature from inception to December 2014 on PubMed and Ovid MEDLINE.

Endosonographic and cyst fluid characteristics of cystic pancreatic neuroendocrine tumours: a multicentre case series

BACKGROUND

Pancreatic neuroendocrine tumours are uncommon neoplasms which may rarely be cystic. Differentiation from other more common cystic neoplasms may be difficult.

AIMS

To describe the morphologic, cytologic, and cyst fluid characteristics of cystic pancreatic neuroendocrine tumours.

METHODS

Retrospective analysis of consecutive patients referred for endosonographic evaluation of pancreatic cysts at four centres.

RESULTS

27 patients (12 males) with cystic pancreatic neuroendocrine tumours were identified. Prior to endosonography, this tumour was suspected in only 2 patients based on presenting symptoms (7.4%). The median cyst size was 35 mm (range 8-80 mm). Wall thickening was identified in 13 cases. The median carcinoembryonic antigen level was 1.25 (range 0.6-500). Fine needle aspiration cytology in 17 of 24 patients confirmed neuroendocrine tumour (71%). In 8 of 9 patients who had needle targeting of the cyst wall, cytology was consistent with neuroendocrine tumour (88.9%). 18 patients underwent surgical resection.

CONCLUSIONS

Cystic pancreatic neuroendocrine tumour was rarely suspected, including by cross-sectional imaging. Wall thickening was identified in approximately half of cases on endosonography. Cyst fluid was typically non-viscous with very low carcinoembryonic antigen levels. Targeting the wall during fine needle aspiration had a high diagnostic yield and should be performed.

Lymphoepithelial cyst of the pancreas in female children--report of two cases

Lymphoepithelial cyst (LEC) of the pancreas is almost always reported as a case report or in small series mostly in male adult patients with vague clinical manifestations and difficult pre-operative diagnosis. Between the years 2007 and 2012, two female children with LEC of the pancreas were operated on at the Children's Surgical Unit of Murtala Mohammad Specialist Hospital, Kano in northern Nigeria. Satisfactory outcomes were achieved after distal pancreatectomy and splenectomy in one and a Whipple procedure in the other. This benign lesion of the pancreas should be considered in the differential diagnosis of cystic lesions of the pancreas in children.

Primary pancreatic cystic neoplasms of the pancreas revisited. Part IV: rare cystic neoplasms

Primary pancreatic cystic neoplasms are being recognized with increasing frequency due to modern imaging techniques. In addition to the more common cystic neoplasms-serous cystadenoma, primary mucinous cystic neoplasm, and intraductal papillary mucinous neoplasm-there are many other less common neoplasms that appear as cystic lesions. These cystic neoplasms include solid pseudopapillary neoplasm of the pancreas (the most common rare cystic neoplasm), cystic neuroendocrine neoplasm, cystic degeneration of otherwise solid neoplasms, and then the exceedingly rare cystic acinar cell neoplasm, intraductal tubular neoplasm, angiomatous neoplasm, lymphoepithelial cysts (not true neoplasms), and few others of mesenchymal origin. While quite rare, the pancreatic surgeon should at the least consider these unusual neoplasms in the differential diagnosis of potentially benign or malignant cystic lesions of the pancreas. Moreover, each of these unusual neoplasms has their own natural history/tumor biology and may require a different level of operative aggressiveness to obtain the optimal outcome.

Preoperative gemcitabine and oxaliplatin in a patient with ovarian metastasis from pancreatic cystadenocarcinoma

We describe a case of clinical benefit and partial response with gemcitabine and oxaliplatin (GEMOX) in a young patient with ovarian metastasis from cystadenocarcinoma of the pancreas. A young woman complained of abdominal pain and constipation. Computed tomography (CT) and magnetic resonance imaging scans disclosed two bilateral ovarian masses with pancreatic extension. She underwent bilateral ovarian and womb resection. During surgery peritoneal carcinosis, a pancreatic mass and multiple abdominal lesions were found. The final diagnosis was mucinous pancreatic cystadenocarcinoma with ovarian and peritoneal metastases. She started chemotherapy with GEMOX (gemcitabine 1,000 mg/m(2)/d1 and oxaliplatin 100 mg/m(2)/d2 every 2 weeks). After 12 cycles of chemotherapy a CT scan showed reduction of the pancreatic mass. She underwent distal pancreatic resection, regional lymphadenectomy and splenectomy. Pathologic examination documented prominent fibrous tissue and few neoplastic cells with mucin-filled cytoplasm. Chemotherapy was continued with gemcitabine as adjuvant treatment for another 3 cycles. There is currently no evidence of disease. As reported in the literature, GEMOX is associated with an improvement in progression-free survival and clinical benefit in patients with advanced pancreatic cancer. This is an interesting case in whom GEMOX transformed inoperable pancreatic cancer into a resectable tumor.

851 resected cystic tumors of the pancreas: a 33-year experience at the Massachusetts General Hospital

BACKGROUND

The objective of this study was to identify trends in the diagnosis and treatment of cystic neoplasms of the pancreas using a retrospective review of patients from a surgical database at an academic referral center during a 33-year period.

METHODS

Patient characteristics, including demographics, pathology, and survival, were analyzed over 5 time periods between 1978 and 2011.

RESULTS

A total of 851 consecutive patients underwent resection for a cystic neoplasm of the pancreas during a 33-year period. Sixty-five percent of patients were female, and mean age was 60 years. The most common pathologic diagnoses were intraductal papillary mucinous neoplasm (38%), mucinous cystic neoplasm (23%), serous cystadenoma (16%), and cystic neuroendocrine neoplasm (7%). There was a stepwise increase in the number of resections across time periods (67 between 1978 and 1989; 376 between 2005 and 2011), with a parallel increase in the proportion of incidentally discovered lesions (22% to 50%). Diagnosis of intraductal papillary mucinous neoplasm was very uncommon in the first 2 time periods (before the first recognition of intraductal papillary mucinous neoplasm as a distinct entity) but predominated in the last 2 (41% and 49%), and cystic neuroendocrine neoplasms, which constituted 3% of the cystic neoplasms in the first time-period, now comprise more than 8% of pancreatic cystic neoplasms. The proportion of malignant neoplasms decreased over time (41% between 1978 and 1989; 12% between 2005 and 2011), reflecting probably the earlier diagnosis and treatment of premalignant neoplasms. Although operative mortality was minimal (4/849, 0.5%), the postoperative complication rate was 38%. Overall 5-year survival for all mucinous lesions was 87%.

CONCLUSION

Cystic neoplasms of the pancreas are being diagnosed and treated with increasing frequency. At present, most are incidentally discovered intraductal papillary mucinous neoplasms.

Pancreatic cystic lesions: How endoscopic ultrasound morphology and endoscopic ultrasound fine needle aspiration help unlock the diagnostic puzzle

Cystic lesions of the pancreas are being diagnosed with increasing frequency, covering a vast spectrum from benign to malignant and invasive lesions. Numerous investigations can be done to discriminate between benign and non-evolutive lesions from those that require surgery. At the moment, there is no single test that will allow a correct diagnosis in all cases. Endoscopic ultrasound (EUS) morphology, cyst fluid analysis and cytohistology with EUS-guided fine needle aspiration can aid in this difficult diagnosis.

18F-fluorodeoxyglucose positron emission tomography in management of pancreatic cystic tumors

OBJECTIVES

To evaluate the effectiveness of PET in differentiating malignant from benign pancreatic cystic tumors.

METHODS

Between 2009 and 2010, all patients with pancreatic cystic tumors who had PET, triple phase contrast computed tomography (CT) and endoscopic ultrasound (EUS) were reviewed. Clinicopathological characteristics and final histology were correlated with preoperative PET, CT and EUS to assess the value of each modality in detecting malignant from benign lesions for clinical decision-making.

RESULTS

Twenty of a total of 116 patients with pancreatic cystic tumors had 18F-FDG PET because of diagnostic difficulties after evaluation with conventional modalities. Sensitivity and specificity of PET in differentiating malignant from benign pancreatic cystic tumors were 100% and 93.75%, with an accuracy of 95%. PET had the best sensitivity, specificity and accuracy for detecting malignant cystic tumors compared with CT and EUS. In 5 cases, the PET results altered the treatment options completely to follow-up instead of surgery (n=2), limited resection instead of Whipple's resection (n=1), and surgery instead of follow-up (n=2).

CONCLUSIONS

PET is an accurate, non-invasive method to distinguish malignant from benign pancreatic cystic tumors and can be used as an adjunct to facilitate clinical decision making.

Diagnostic and radiological management of cystic pancreatic lesions: important features for radiologists

Cystic pancreatic neoplasms are often an incidental finding, the frequency of which is increasing. The understanding of such lesions has increased in recent years, but the numerous types of lesions involved can hinder differential diagnosis. They include, in particular, intraductal papillary mucinous neoplasms (IPMN), serous cystic neoplasms (SCN), and mucinous cystic neoplasms (MCN). Knowledge of their histological and radiological structure, as well as distribution in terms of localization, age, and sex, helps to differentiate such tumours from common pancreatic pseudocysts. Several types of cystic pancreatic neoplasms can undergo malignant transformation and, therefore, require differentiated radiological management. This review aims to develop a broader understanding of the pathological and radiological characteristics of cystic pancreatic neoplasms, and provide a guideline for everyday practice based on current concepts in the radiological management of the given lesions.

Individuals at high-risk for pancreatic cancer development: management options and the role of surgery

Pancreatic cancer (PC) is a highly lethal disease. Despite advances regarding the safety and long-term results of pancreatectomies, early diagnosis remains the only hope for cure. This necessitates the implementation of an intensive screening program (based mainly on modern imaging), which - given the incidence of PC - is not cost effective for the general population. However, this screening program is recommended for individuals at high-risk for PC development. Indications for screening include the following three clinical settings: hereditary cancer predisposition syndromes associated with PC, hereditary pancreatitis and familial pancreatic cancer syndrome. The aim of this strategy is to identify pre-invasive (precursor) lesions, which are curable. Surgery is recommended in the presence of recognizable lesion on imaging lesions. Partial (anatomic) pancreatectomy - depending on the location of the suspicious lesion - is the most widely accepted type of surgical intervention in this setting; occasionally, however, total pancreatectomy may be required, in carefully selected patients. Despite that experience still remains limited, there is evidence that this aggressive strategy allows early detection of neoplastic lesions, thereby improving the effectiveness of surgery and prognosis.

Epidemiology, diagnosis, and management of cystic lesions of the pancreas

Although little is known on the true prevalence of pancreatic cysts, physicians are currently more frequently confronted with pancreatic cysts because of the increasing use of sophisticated cross-sectional abdominal imaging. Cystic lesions of the pancreas comprise of a heterogeneous group of diagnostic entities, some of which are benign such as inflammatory pseudocysts or serous cystadenomas and do not require resection when asymptomatic. Others like mucinous cysts or intraductal papillary mucinous neoplasms (IPMN) have a malignant potential and in these cases surgical resection is often indicated. For this reason an adequate distinction between the various cysts is crucial to optimize management strategy. Different diagnostic methods that could be of value in the differentiation include radiologic imaging techniques such as CT, MR, and endosonography. In addition, fluid aspiration for cytopathology, tumormarkers or molecular analysis is widely used. Different guidelines are available but so far no optimal diagnostic algorithm exists. We summarize the epidemiology, classification, clinical presentation, diagnostics, management, and future perspectives.

Progress in research of intraductal papillary mucinous neoplasms

Intraductal papillary mucinous neoplasms (IPMNs) represent a spectrum of neoplasms arising from the main pancreatic duct or branch ducts and producing mucin and can be regarded as a type of precancerous lesions. Thanks to improvements in endoscopy and imaging techniques, IPMNs are being diagnosed with increasing frequency. However, there are currently no highly sensitive and specific preoperative criteria available to distinguish benign IPMNs from malignant ones. What's more, the necessity for EUS and ERCP in the diagnosis of IPMNs is still under debate. Here, we review recent advances in research of IPMNs and summarize potential differences between benign and malignant IPMNs.

Potential pitfalls in the management of primary pancreatic cystic neoplasms

Primary pancreatic cystic neoplasms (PCN) have been increasingly recognized over the last 2 decades, mainly as a result of the widespread use of modern imaging techniques in patients with abdominal complaints. Biological behavior and management greatly differ between subgroups of PCN. Accurate preoperative diagnosis is required to select the optimal management strategy for each individual patient with PCN. An in-depth knowledge of the biological, imaging, macroscopic/microscopic features, and laboratory findings of each subtype of PCN is required on the part of the clinician, in order to select a cost-effective diagnostic evaluation of the patient. Clinical judgment is also required on the part of the surgeon to select the optimal procedure and to avoid severe pitfalls in the surgical management of these neoplasms.

Additional value of FDG PET/CT to contrast-enhanced CT in the differentiation between benign and malignant intraductal papillary mucinous neoplasms of the pancreas with mural nodules

OBJECTIVES

This study aimed at determining the additional value of FDG PET/CT to contrast-enhanced CT in the differentiation between benign and malignant intraductal papillary mucinous neoplasms (IPMNs) of the pancreas with mural nodules.

METHODS

This retrospective review of medical records was approved by our institutional review board. The preoperative PET/CT images of 16 non-diabetic patients with surgically proven IPMN, where mural nodules of 3 mm or larger were shown by preoperative contrast-enhanced CT, were retrospectively evaluated. The 16 patients were divided into two groups: 7 patients with benign IPMN [adenoma (n = 1) and borderline tumor (n = 6)] and 9 patients with malignant IPMN [carcinoma in situ (CIS) (n = 8) and invasive carcinoma (n = 1)]. Nuclear medicine physician blinded to the pathologic assessment of malignancy of IPMN set a spherical volume of interest (VOI) over the mural nodules on PET/CT images and recorded the peak standardized uptake value (SUV(max)) in the VOI, referring the contrast-enhanced CT images. Statistical differences in the size of mural nodule, the diameter of main pancreatic duct (MPD), and SUV(max) of the tumors between benign IPMNs and malignant IPMNs were compared using the Mann-Whitney U test. Statistical significance was set at p < 0.05. Additionally, the diagnostic accuracy of FDG PET for the detection of malignancy was calculated.

RESULTS

The SUV(max) of the malignant IPMNs with mural nodules of 3 mm or larger was higher than that of benign IPMNs (2.7 ± 0.6 vs. 1.9 ± 0.3, p < 0.01). Meanwhile, there was no significant difference in mural nodule diameter and MPD diameter between the two groups. FDG PET/CT showed an excellent diagnostic accuracy for the differentiation between malignant and benign IPMNs with mural nodules: the sensitivity, specificity, PPV, NPV, and accuracy in malignant IPMN with mural nodule of FDG PET/CT were 77.8, 100, 100, 77.8, and 87.5 for the cutoff value of 2.3; and 100, 57.1, 75.0, 100, and 81.3 for the cutoff value of 2.0, respectively.

CONCLUSIONS

The result of this study indicates that FDG PET/CT can provide additional information for the differentiation between benign and malignant IPMNs of the pancreas with mural nodules.

Primary pancreatic cystic neoplasms revisited. Part III. Intraductal papillary mucinous neoplasms

Intraductal papillary mucinous neoplasms (IPMNs) represent about 25% of all primary pancreatic cystic neoplasms and are increasingly recognized during the last two decades. They are characterized by intraductal proliferation of neoplastic mucinous cells forming papillary projections into the pancreatic ductal system, which is typically dilated and contains globules of mucus. IPMNs may be multifocal and have malignant potential. Modern imaging is essential in establishing preoperative diagnosis and in differentiating different subtypes of IPMNs (i.e., main-duct vs. branch-type disease). Endoscopic retrograde or magnetic resonance cholangiopancreatography accurately delineate the morphologic changes of the pancreatic ductal system. Endoscopic ultrasonography (usually used in conjunction with image-guided FNA and analysis of the aspirated material) is commonly used for differential diagnosis of IPMNs from other pancreatic cystic lesions. Surgical resection (usually anatomic pancreatectomy, depending on the location of the disease) is the treatment of choice. Total pancreatectomy may occasionally be required in selected patients, but is associated with formidable long-term morbidity. A conservative approach has recently been proposed for carefully selected patients with branch-duct IPMNs. Recurrences following surgical resection can be observed, especially in patients with multifocal disease or in the presence of underlying malignancy.

Primary pancreatic cystic neoplasms revisited: part II. Mucinous cystic neoplasms

Mucinous cystic neoplasms (MCNs) of the pancreas represent one of the most common primary pancreatic cystic neoplasms, accounting for approximately half of these cases. MCNs are observed almost exclusively in women, and most commonly are located in the body/tail of the pancreas. In contrast to SCNs, MCNs have malignant potential. Proliferative changes (hyperplasia with or without atypia, borderline changes, non-invasive or carcinomas in-situ, and invasive carcinomas) can often be observed within the same neoplasm. Several risk factors for the presence of underlying malignancy within an MCN have recently been recognized. Cross-sectional imaging is of key importance for the diagnostic evaluation of patients with a cystic pancreatic lesion. Cyst fluid examination (cytology, biochemical/genetic analysis) is possible by using fine needle aspiration of the MCN, usually under endoscopic guidance, and may provide useful information for the differential diagnosis. Since MCNs have malignant potential, surgical resection is the treatment of choice.

Primary pancreatic cystic neoplasms revisited. Part I: serous cystic neoplasms

Primary pancreatic cystic neoplasms have been recognized increasingly during the two recent decades and include mainly serous cystic neoplasms, mucinous cystic neoplasms, and intraductal papillary mucinous neoplasms. Serous cystic neoplasms represent about 30% of all cystic neoplasms of the pancreas and are characterized by their microcystic appearance (on imaging, macroscopically, and microscopically) and their benign biologic behavior. Modern diagnostic methodology allows the preoperative diagnosis with an acceptable accuracy. Currently, indications for resection of serous cystic neoplasms of the pancreas include the presence of symptoms, size > 4 cm (because these 'large' neoplasms have a more rapid growth rate and probably will soon become symptomatic), and any uncertainty about the diagnosis of a serous versus a mucinous cystic neoplasm. Resection should also be considered for lesions in the body/tail of the pancreas. Conservative treatment is a reasonable option in selected patients (for example in the presence of small, asymptomatic lesions in the pancreatic head, especially in the frail or elderly patient).

Pleomorphic giant cell carcinoma of the pancreas with hepatic metastases--initially presenting as a benign serous cystadenoma: a case report and review of the literature

INTRODUCTION

Pleomorphic giant cell pancreatic cancer is a very rare and aggressive pancreatic neoplasm. A case of pleomorphic giant cell pancreatic cancer presenting as a cystic lesion and in association with a serous cystadenoma presents a unique case which has not been described before.

CASE PRESENTATION

A 44-year-old alcoholic man presented with abdominal pain, vomiting, and weight loss. Initially, imaging suspected a pancreatic pseudocyst measuring 4.2 cm. Endoscopic ultrasound- (EUS-) guided fine-needle aspiration revealed a serous cystadenoma. With conservative intervention only (fluid resuscitation, analgesia, and antiemetics) the patient improved and was discharged under close observation. Follow-up scan at four months revealed minimal change. Three months later, he was admitted acutely. Repeat scans demonstrated mild cyst enlargement with new liver lesions. Laparoscopic biopsy revealed pleomorphic giant cell carcinoma with the organ of origin the pancreas.

CONCLUSION

This unusual case highlights the challenges in managing pancreatic cystic lesions and emphasizes the importance of considering less common forms of pancreatic cystic masses when the findings are atypical for the presentation. Surgical excision in these cases over conservative steps may be the most appropriate management.

Cystic neoplasms of the pancreas

Cystic neoplasms of the pancreas are a heterogeneous group of pancreatic tumors that vary in pathophysiology, malignant potential, clinical course, and outcomes. Their management is heavily predicated on establishing an accurate diagnosis. This can be particularly challenging, but can often be achieved by a thorough history and physical examination combined with high-quality, thin-slice computed tomography, although additional diagnostic tools may be required. Once the diagnosis is established, treatment can range from simple observation to total pancreatectomy. This decision rests on a clear and complete understanding of each disease process in the context of the patient's age and comorbidities. This article reviews the most common cystic neoplasms of the pancreas, focusing on their diagnosis and management.

Tumors of the Pancreatic Body and Tail

Tumors of the pancreatic body and tail are uncommon. They have a propensity to present late and often attain a large size with local invasion before they produce any clinical symptoms. The current review aims at comprehensively analysing these tumors with respect to their pathology, presentation, the investigation of these tumors, and finally the latest trends in their surgical and medical management.

Defining criteria for selective operative management of pancreatic cystic lesions: does size really matter?

INTRODUCTION

Proposed criteria for resection of pancreatic cystic lesions have included symptoms, size (>3 cm), and suspicious features by endoscopic ultrasound (EUS). The objective of this study was to evaluate risk factors for malignancy in a large series of patients undergoing resection of suspected pancreatic cystic neoplasms.

METHODS

Medical records of patients selected for resection of pancreatic cystic lesions at Duke University Medical Center from 2000 to 2008 were reviewed. Lesions with solid components on cross-sectional imaging were excluded. Malignancy was defined as invasive or in situ carcinoma.

RESULTS

After review, 101 patients were confirmed to have undergone resection for suspected cystic neoplasms of the pancreas. Preoperative EUS was performed in 71 patients. Sixteen patients (16%) had malignant lesions (preoperative size 1.5-5.9 cm). There was no clear association between size and malignancy. Male gender, biliary ductal dilatation (BDD), pancreatic ductal dilatation (PDD), and suspicious cytology (but not age, symptoms, or size) were associated with increased risk of malignancy. When factors available for all patients were incorporated into a multivariate model, only BDD and PDD were independent risk factors for malignancy. Only one patient with malignancy had neither BDD nor PDD but did have solid components by EUS.

CONCLUSIONS

In patients selected for resection, size was not an independent risk factor for malignancy. While size might be appropriate for stratification of asymptomatic patients with simple cysts, size should not be used as a selection criterion for patients who have cysts with solid components or with associated BDD or PDD.

Endoscopic ultrasound-guided fine needle aspiration (EUS-FNA): experience of an academic centre in the USA

OBJECTIVES

Endoscopic ultrasound-guided fine needle aspiration (EUS-FNA) has become widely accepted as an effective modality for obtaining tissue for primary diagnosis and staging. We have been using EUS-FNA since July 2001 and herein we summarize our experience over a 5-year period.

METHODS

A computer-based search for in-house EUS-FNA was performed in the pathology database from July 2001 to October 2006. To calculate the sensitivity, specificity and accuracy of EUS-FNA, the cytology diagnosis was compared with the surgical follow-up.

RESULTS

A total of 951 EUS-FNAs were performed during the study period and included 279 pancreatic solid lesions, 186 pancreatic cyst lesions, 249 lymph node aspirations, 111 gastrointestinal (GI) tract submucosal lesions, and 126 miscellaneous lesions. EUS-FNA had a very high sensitivity and accuracy for solid pancreatic lesions (94.7 and 97.7%, respectively), low sensitivity and accuracy but high specificity (47, 64.8 and 95%, respectively) for cystic lesions. Cyst fluid carcinoembryonic (CEA) levels were significantly higher in mucinous neoplasms than non-neoplastic cysts. EUS-FNA also had very high sensitivity and specificity for detecting metastatic carcinoma in lymph nodes (95 and 100%, respectively). GI submucosal spindle cell tumours were further classified with immunohistochemical stains performed either on a cell block or a core biopsy obtained via EUS guidance.

CONCLUSIONS

EUS-FNA has a very high sensitivity and accuracy for pancreatic solid lesions, but the sensitivity for cystic lesions is generally low. Cyst fluid chemical analysis for CEA is helpful, but the overlap between mucinous neoplasm and non-neoplastic cysts is significant. Recognizing GI contamination is important and immunohistochemical stains are useful for GI submucosal spindle cell lesions.

Fine-needle aspiration of cystic pancreatic mucinous tumor: oncotic cell as an aiding diagnostic feature in paucicellular specimens

In juxtaposition with imaging studies, endoscopic ultrasound-guided fine-needle aspiration has gained popularity in the initial evaluation of pancreatic masses, especially cystic lesions of pancreas. Cystic pancreatic mucinous tumors include mucinous cystic neoplasm and intraductal papillary mucinous tumor, both of which have been known to have a low malignant potential and a high rate of association with invasive adenocarcinoma. As such, preoperative diagnosis is of great significance in guiding patient management. Although fine-needle aspiration cytological diagnosis of pancreatic tumor in cellular specimens has been well described, as with other cystic lesions, the yield of diagnostic cells from needle aspiration of cystic pancreatic mucinous tumors is typically low. Cytological diagnosis from these paucicellular specimens remains challenging. An additional compounding problem is the high frequency of gastrointestinal mucin and epithelial contamination. The diagnostic morphology and criteria in these paucicellular specimens have not been well addressed in the literature. The cytopathologists' ongoing efforts tend to improve the diagnostic accuracy. In this current study, oncotic cells, characterized by cytoplasmic swelling and karyolysis, were analyzed from 17 cases of cystic pancreatic mucinous tumor, of which the diagnosis was either confirmed by surgical resection or supported by cell block and/or increased CEA. Oncotic cells were found in variable amounts in almost all the cystic pancreatic mucinous tumors in this series. None of the five fine-needle aspirations intended for aspirations of hypoechoic nonlesional pancreas, which yielded either gastrointestinal tract material only or admixture of gastrointestinal and normal pancreatic components, was found to contain oncotic cells, evidencing the utility of oncotic cell as a surrogate morphologic marker in aiding the diagnosis of cystic pancreatic mucinous tumor as well as its differentiation from gastrointestinal contaminant, particularly in paucicellular specimens.

Cystic neoplasms of the pancreas: A diagnostic challenge

Cystic neoplasms of the pancreas are increasingly recognized due to the expanding use and improved sensitivity of cross-sectional abdominal imaging. Major advances in the last decade have led to an improved understanding of the various types of cystic lesions and their biologic behavior. Despite significant improvements in imaging technology and the advent of endoscopic-ultrasound (EUS)-guided fine-needle aspiration, the diagnosis and management of pancreatic cystic lesions remains a significant clinical challenge. The first diagnostic step is to differentiate between pancreatic pseudocyst and cystic neoplasm. If a pseudocyst has been effectively excluded, the cornerstone issue is then to determine the malignant potential of the pancreatic cystic neoplasm. In the majority of cases, the correct diagnosis and successful management is based not on a single test but on incorporating data from various sources including patient history, radiologic studies, endoscopic evaluation, and cyst fluid analysis. This review will focus on describing the various types of cystic neoplasms of the pancreas, their malignant potential, and will provide the clinician with a comprehensive diagnostic approach.

Surgical therapy of pancreatic pseudocysts

BACKGROUND

Pancreatic pseudocysts are a common complication associated with acute and chronic pancreatitis. Fifteen percent and 40% of patients diagnosed with either acute or chronic pancreatitis, respectively, develop pseudocysts (Grace and Williamson, Br J Surg, 80:573-581, 1993). The treatment of pancreatic pseudocysts has evolved since the early 1980s, and changes in management have lead to an improved understanding of the pathophysiology of pseudocysts as well as necessary treatment paradigms.

CONCLUSIONS

It has become evident that not all pseudocysts are equal. Pseudocysts arising in the setting of acute pancreatitis have a different pathophysiologic basis than those arising from chronic pancreatitis. Moreover, even those pseudocysts that arise in acute pancreatitis exhibit unique features. Pseudocysts that develop from a mild episode of pancreatitis, complicated by pancreatic duct disruption, differ significantly from those developed as a consequence of severe acute necrotizing pancreatitis with severe distortion of the pancreatic parenchyma or pancreatic duct. This review will focus on the surgical therapy of pancreatic pseudocysts in the context of the underlying pathophysiology and alternative nonoperative therapies.

Overview of the clinical problem: facts and current issues of mucinous cystic neoplasms of the pancreas

Pancreatic cystic lesions are uncommon and consist of pseudocysts, congenital cysts and cystic neoplasms including mucinous cystic neoplasms, intraductal papillary mucinous neoplasms and serous cystic neoplasms. Mucinous cystic neoplasms are large septated cysts without connection to the ductal system, characterised by the presence of thick-walled ovarian-type stroma and mucin. They occur predominantly in women and often are malignant. Therefore, surgical resection is recommended. Intraductal papillary mucinous neoplasms are neoplasms with tall, columnar, mucin-containing epithelium involving the main pancreatic ducts or major side branches. Intraductal papillary mucinous neoplasms occur in men and women in their 60s and 70s and may differentiate into malignant neoplasms. Therefore, surgical resection is mandatory. Serous cystic neoplasms appear as multiple cysts lined with cubic flat epithelium containing glycogen-rich cells with clear cytoplasm. They mainly occur in women in their 50s and are generally benign. Therefore, a conservative approach is recommended. As both mucinous cystic neoplasm and intraductal papillary mucinous neoplasms have a high malignant potential, it is important to differentiate between the various pancreatic cystic lesions. Several imaging techniques and tumour markers have been evaluated. Nonetheless, definitive guidelines to differentiate between serous cystic neoplasms, mucinous cystic neoplasms and intraductal papillary mucinous neoplasms are still poorly defined. A number of management issues regarding these neoplasms are still under debate, for example which imaging technique to use, differentiation between malignant or benign lesions and the preferred treatment modality for each pancreatic cystic neoplasm. Further research may lead to a definitive guideline for the diagnosis and treatment of mucinous cystic neoplasms, intraductal papillary mucinous neoplasms and serous cystic neoplasms.

Role of endosocopic ultrasound in the diagnosis of cystic tumours of the pancreas

With the increased use of sophisticated imaging, cystic lesions in the pancreas are being recognized with greater frequency. Although imaging alone may not provide a specific diagnosis in many cases, a combination of imaging characteristics, clinical presentation, and additional procedures such as endoscopic ultrasound guided fine needle aspiration of cystic lesion, allows appropriate management. Cystic lesions in the pancreas can be divided pathologically into congenital cysts, pseudocysts and cystic neoplasm. At least four different types of cystic neoplasm have been described: mucinous neoplasms, intraductal papillary mucinous neoplasms, serous neoplasms and papillary cystic neoplasms The most important diagnosis is differentiating between mucinous and non-mucinous cystic lesion because of their different potential of malignancy. Endoscopic ultrasound provides the highest resolution of the pancreas and endoscopic ultrasound-fine needle aspiration can supply further diagnostic information on the basis of cytology, fluid viscosity, concentration of tumour glycoproteins, amylase level, molecular analysis that may contribute to the better clinical outcome of these neoplasms.

Macrocystic pancreatic lesions: differentiation of benign from premalignant and malignant cysts by CT

OBJECTIVE

To assess useful CT features for differentiating benign from premalignant and malignant macrocystic pancreatic lesions.

METHODS

Seventy-four patients with pathologically proven macrocystic pancreatic lesions were enrolled: 17 benign cysts (macrocystic serous cystadenoma, n=12; congenital cyst; n=5) and 57 premalignant and malignant cysts (mucinous cystic neoplasm, n=28; intraductal papillary mucinous neoplasm of branch duct type, n=20; tumor with cystic change, n=9). Size, location, shape (lobulated, round or oval, or complex cystic with tubular cyst), wall thickness (thin, < or =1mm; thick, >1mm), internal surface (smooth or irregular), and other findings were analyzed with multiphasic CT with thin-section (2.5-3mm) images. CT features between two groups were compared using univariate and multivariate stepwise logistic regression analyses.

RESULTS

On univariate analysis, the differences for the shape (p=0.007), wall thickness (p=0.011), and internal surface (p=0.012) between benign and premalignant and malignant cysts were significant. A lobulated shape, a thin wall and a smooth internal surface were more frequent in benign cysts, whereas a round or oval shape or a complex cystic shape with tubular cyst, a thick wall and an irregular internal surface were more frequent in premalignant and malignant cysts. On multivariate analysis, the shape (p=0.002) and wall thickness (p=0.025) were significant CT features for differentiating benign from premalignant and malignant cysts.

CONCLUSION

Shape and wall thickness are the main CT features for differentiating benign from premalignant and malignant macrocystic pancreatic lesions.

18-fluorodeoxyglucose positron emission tomography enhances computed tomography diagnosis of malignant intraductal papillary mucinous neoplasms of the pancreas

OBJECTIVE

To assess the reliability of 18-fluorodeoxyglucose positron emission tomography (18-FDG PET) in distinguishing benign from malignant intraductal papillary mucinous neoplasms (IPMNs) of the pancreas and its contribution to surgical decision making.

SUMMARY BACKGROUND DATA

Pancreatic IPMNs are increasingly recognized, often as incidental findings, especially in people over age 70 and 80. Computed tomography (CT) and magnetic resonance (MR) are unreliable in discriminating a benign from a malignant neoplasm. 18-FDG PET as imaging procedure based on the increased glucose uptake by tumor cells has been suggested for diagnosis and staging of pancreatic cancer.

METHODS

From January 1998 to December 2005, 64 patients with suspected IPMNs were prospectively investigated with 18-FDG PET in addition to conventional imaging techniques [helical-CT in all and MR and magnetic resonance cholangiopancreatography (MRCP) in 60]. 18-FDG PET was analyzed visually and semiquantitatively using the standard uptake value (SUV). The validation of the diagnosis was made by a surgical procedure (n = 44), a percutaneous biopsy (n = 2), main duct cytology (n = 1), or follow-up (n = 17). Mean and median follow-up times were 25 and 27.5 months, respectively (range, 12-90 months).

RESULTS

Twenty-seven patients (42%) were asymptomatic. Forty-two patients underwent pancreatic resection, 2 palliative surgery, and 20 did not undergo surgery. An adenoma was diagnosed in 13 patients, a borderline tumor in 8, a carcinoma in situ in 5, and an invasive cancer in 21; in 17 patients a tumor sampling was not performed and therefore the histology remained undetermined. Positive criteria of increased uptake on 18-FDG PET was absent in 13 of 13 adenomas and 7 of 8 borderline IPMNs, but was present in 4 of 5 carcinoma in situ (80%) and in 20 of 21 invasive cancers (95%). Conventional imaging technique was strongly suggestive of malignancy in 2 of 5 carcinomas in situ and in 13 of 21 invasive carcinomas (62%). Furthermore, conventional imaging had findings that would be considered falsely positive in 1 of 13 adenomas (8%) and in 3 of 8 borderline neoplasms (37.5%). Therefore, positive 18-FDG PET influenced surgical decision making in 10 patients with malignant IPMN. Furthermore, negative findings on 18-FDG PET prompted us to use a more limited resection in 15 patients, and offered a follow-up strategy in 18 patients (3 positive at CT scan) for the future development of a malignancy.

CONCLUSIONS

18-FDG PET is more accurate than conventional imaging techniques (CT and MR) in distinguishing benign from malignant (invasive and noninvasive) IPMNs. 18-FDG PET seems to be much better than conventional imaging techniques in selecting IPMNs patients, especially when old and asymptomatic, for surgical treatment or follow-up.

The management of cystic lesions of the pancreas

The number of patients being identified as having asymptomatic small cysts of the pancreas is increasing. Most cystic neoplasms are SCAs, IPMNs, or MCNs. SCAs should be considered benign and in the absence of symptoms can be safely followed radiographically. Currently, most patients who present with mucinous cysts should undergo resection, because many of these patients have in situ or invasive carcinoma. The presence of a solid component seems to be associated with malignancy in patients who have mucinous cysts, and cyst size seems to be associated with malignancy in patients who have MCNs and branch duct IPMNs. Many institutions now are reporting a selective approach to resection in patients who have cystic lesions of the pancreas. Routine resection of all pancreatic cysts currently is impractical; given the large numbers of patients being identified with lesions smaller than 2 cm, this approach would result in a mortality rate that is much higher than the rate of malignancy. Most studies that have advocated a selective approach have reported the radiographic characteristics of a solid component, cyst size, and symptoms to be associated with treatment recommendations. The authors believe that radiographic follow-up is warranted in any patient for whom the assumed risk of malignancy is less than the risk of mortality from resection (no solid component, < 3 cm, asymptomatic). Most patients who have incidentally discovered cysts smaller than 3 cm in diameter and without a solid component can be safely followed radiographically. In the young patient who has a small mucinous tumor, additional factors to be considered are the likelihood of progression to malignancy and patient anxiety about radiographic follow-up. No data are available for the former. Efforts should be made to improve the ability to distinguish histopathologic subtypes without resection. The current challenges are to improve the sensitivity and specificity for the identification of mucinous subtype, to characterize better the progression of IPMN and mucinous cystic tumors, and to develop better methods for identifying the presence of in situ or invasive disease in these patients. Continued improvements in cross-sectional imaging and endoscopic techniques and further investigation into markers in the serum and cyst fluid should allow better identification of mucinous subtypes.

Curative laparoscopic resection for pancreatic neoplasms: a critical analysis from a single institution

Laparoscopic pancreatic surgery (LPS) has seen significant development but much of the knowledge refers to small and benign pancreatic tumors. This study aims to evaluate the feasibility, safety, and long-term outcome of the laparoscopic approach in patients with benign, premalignant, and overt malignant lesions of the pancreas. This study, currently, is the largest single center experience worldwide. One hundred twenty-three consecutive patients underwent laparoscopic pancreatic surgery from April 1998 to April 2007, 20 patients with cysts or pseudocysts for acute and chronic pancreatitis, laparoscopic pancreatic drainage was performed, and were excluded from the analysis. The 103 patients were divided based on preoperative diagnosis: group I, inflammatory tumors for chronic pancreatitis (eight patients); group II, cystic pancreatic neoplasms (29 patients); group III, intraductal papillary mucinous neoplasms (10 patients); group IV, neuroendocrine pancreatic tumors (NETs) (43 patients); and group V ductal adenocarcinoma (13 patients). The median tumor size was 5.3 cm. Pathologic data include R(0) or R(1) resection (transection margins on the specimen were inked). Perioperative data, postoperative complications, and resection modalities were compared using statistical analysis. Long-term outcomes were analysed by tumor recurrence and patient survival. The overall conversion rate was 7%. Laparoscopic distal pancreatic resection was performed in 82 patients (79.6%). Laparoscopic spleen-preserving distal pancreatectomy (Lap SPDP) was performed in 52 patients (63.7%), but with splenic vessels preservation in 22% and without splenic vessels preservation in 41.5%. Laparoscopic en-bloc splenopancreatectomy (Lap SxDP) was performed in 30 patients (36.6%) and laparoscopic enucleation (Lap En) in 20 patients (19.4%). There was no mortality. The overall complication rate was 25.2, 16.7, and 40% after Lap SPDP, Lap SxDP, and Lap En, respectively. The overall morbidity rate was significantly higher (p>0.05) in the group of Lap SPDP without splenic vessels preservation comparing with Lap SPDP with splenic vessels preservation because of the occurrence of splenic complications (20.6%). The overall pancreatic fistulas was 7.7, 10, and 35% after Lap SPDP, Lap SxDP, and Lap En, respectively; the severity of fistula was significantly higher in the Lap En group (p>0.05). The mean hospital stay was within 1 week in all groups, except in the group of ductal adenocarcinoma, which is 8 days. In this series, 27 patients (26.2%) had malignant disease. R(0) resection was achieved in 90% of ductal adenocarcinoma and 100% for other malignant tumors. The median survival for ductal adenocarcinoma patients was 14 months. This series demonstrates that LPS is feasible and safe in benign-appearing and malignant lesions of the pancreas.

[Pancreatic incidentalomas. Correct assessment and therapy]

Due to recent advances in CT/MRI technology, incidentalomas of the pancreas are detected with increasing frequency. Pancreatic incidentalomas should be differentiated into solid and cystic tumors. In both subgroups definitive classification of the tumor is often not possible. Operative therapy is recommended in premalignant or malignant pathologies. Thus solid incidentalomas should be resected independently of their size, if the patient is without serious comorbidities. In case of cystic incidentalomas, benign cystic lesions should be excluded as far as possible. Otherwise they should be resected if their size is >or=2 cm. In case of IPMN with specific risk factors, resection is recommended when the tumor size exceeds 1 cm.

Noninvasive pancreatic cystic neoplasms can be safely and effectively treated by limited pancreatectomy

BACKGROUND

Appropriate management of cystic lesions of the pancreas is controversial. Major pancreatectomies (pancreaticoduodenectomy or distal pancreatectomy with splenectomy) are the commonly used procedures, even though most cystic lesions are noninvasive neoplasms. We tested the adequacy of limited pancreatectomies in the treatment of pancreatic cystic lesions.

METHODS

Data from 109 patients who underwent surgical resection of a pancreatic cystic lesion at National Taiwan University Hospital from 2001 to 2007 were retrospectively reviewed. Major pancreatomies (n = 79) constituted pancreaticoduodenectomy and total/distal pancreatectomies, while other resection procedures (n = 30) represented limited pancreatectomies. Clinicopathologic features were compared between the major and limited groups.

RESULTS

There were no statistically significant differences in sex, age, presence of symptoms, cyst diameter, minor or major treatment complications, or pancreatic leakage between the two groups. Cystic lesions located in the neck/body/tail rather than in the head/uncinate process were significantly more often treated with limited pancreatectomy (P = .02). Both groups had similar pathologic distribution of cystic lesions, with the exception of nine invasive neoplasms. The latter were treated with major pancreatectomy. No recurrence was noted in 100 patients with noninvasive cystic neoplasms after major or limited pancreatectomy.

CONCLUSIONS

Noninvasive pancreatic cystic neoplasms can be safely and effectively treated by limited pancreatectomy.

Pancreatic cysts: a proposed management algorithm based on current evidence

BACKGROUND

Currently, the management strategy of pancreatic cyst (PC) remains controversial because of the inability to diagnose this type of cyst accurately and the limited knowledge of its natural history. Previously, many clinicians have advocated an aggressive resectional policy. This approach is no longer appropriate, and the number of PCs detected incidentally has increased. This study reviews the present literature and attempts to provide a management algorithm of pancreatic cysts based on currently available evidence.

METHODS

A Medline search was conducted to identify studies investigating PC, with particular emphasis placed on studies addressing its diagnosis and management. Additional articles were obtained from the reference lists of key articles and recent reviews.

COMMENTS

Based on current evidence, the optimal management of PC remains an art and should be individualized based on the risk-benefit ratio of surgery, which is influenced by multiple factors, such as the patient's potential life expectancy, surgical risk; and malignant potential of the cyst. Our proposed management algorithm is based on an individual's predicted risk-benefit ratio of surgery. Prospective evaluation of the algorithm is needed to determine its integrity.