Cystic neoplasms of the pancreas with mucin-production

[Combination of intraductal papillary mucinous neoplasm with other cystic pancreatic tumors]

Cystic tumors of the pancreas are uncommon entities. Synchronic occurrence of intraductal papillary mucinous neoplasm (IPMN) and other pancreatic tumors is extremely rare. Two patients with this diagnosis are reported in the manuscript. Cystic tumors of the pancreas can rarely occur in various combinations while malignancy potential of each neoplasm may be different. Surgery depends on localization and type of each tumor and must be determined individually.

Changing trends in the clinicopathological features, practices and outcomes in the surgical management for cystic lesions of the pancreas and impact of the international guidelines: Single institution experience with 462 cases between 1995-2018

INTRODUCTION

The impact on clinical practice of the international guidelines including the Sendai Guidelines (SG06) and Fukuoka Guidelines (FG12) on the management of cystic lesions of the pancreas (CLP) has not been well-studied. The primary aim was to examine the changing trends and outcomes in the surgical management of CLP in our institution over time and to determine the impact of these guidelines on our institution practice.

METHODS

462 patients with surgically-treated CLP were retrospectively reviewed and classified under the 2 guidelines. The cohort was divided into 3 time periods: 1998-2006, 2007-2012 and 2013 to 2018.

RESULTS

Comparison across the 3 time periods demonstrated significantly increasing frequency of older patients, asymptomatic CLP, male gender, smaller tumor size, elevated Ca 19-9, use of magnetic resonance imaging (MRI) and use of endoscopic ultrasound (EUS) prior to surgery. There was also significantly increasing frequency of adherence to the international guidelines as evidenced by the increasing proportion of HR^SG06 and HR^FG12 CLP with a corresponding lower proportion of LR^SG06 and LR^FG12 being resected. This resulted in a significantly higher proportion of resected CLP whereby the final pathology confirmed that a surgery was actually indicated.

CONCLUSIONS

Over time, there was increasing adherence to the international guidelines for the selection of patients for surgical resection as evidenced by the significantly increasing proportion of HR^SG06 and HR^FG06 CLPs undergoing surgery. This was associated with a significantly higher proportion of patients with a definitive indication for surgery. These suggested that over time, there was a continuous improvement in our selection of appropriate CLP for surgical treatment.

The rare case of a cystic pancreatic neuroendocrine tumor

The pancreatic neuroendocrine tumors (PanNETs) most commonly present as solid neoplasms; however, very rarely, they may present primarily as cystic neoplasms. Most of the cystic PanNETs are non-secreting tumors, and the radiological features are not well defined. Hence pre-operative diagnosis is usually challenging and the tumors are misdiagnosed as mucinous cystic neoplasms, intraductal papillary mucinous neoplasms, serous cystic neoplasms, solid pseudopapillary neoplasms, and non-neoplastic cysts. However, the management depends on the accurate diagnosis of these cystic lesions, which poses a dilemma. Herein, we report the case of a cystic PanNET in the tail of the pancreas, which was clinically and radiologically misdiagnosed as a mucinous cystic neoplasm. This case is reported to highlight this issue to the medical community regarding the diagnostic difficulty in such rare non-functioning pancreatic neuroendocrine tumors.

Diffuse histology-proven mucinous cystic neoplasm of the pancreas: A case report and review of literature

INTRODUCTION

Mucinous cystic neoplasms (MCN) are rare premalignant neoplasms of the pancreas that are typically found as single lesions in the pancreatic body and tail of women in the fifth and sixth decade of life, do not communicate with the pancreatic ductal system and are characterized by mucin-producing epithelium supported by ovarian-type stroma.

PRESENTATION OF CASE

We present here a case of diffuse pancreatic involvement by MCN in a 64-year-old woman with chronic pancreatitis. Pre-operative suspicion for MCN was low due to the multi-centric nature of the lesions and imaging/biochemical fluid analysis demonstrating connection with the pancreatic ductal architecture. The patient underwent total pancreatectomy with pathology showing multiple cysts lined by flat epithelium with focal ovarian-type stroma, consistent with low-grade MCN.

DISCUSSION

The presence of ovarian stroma on histological analysis is one of the defining characteristics of MCNs per WHO guidelines, and is mandatory for its diagnosis. Only one case of diffuse MCN has been previously described in the literature; however, in this case the authors were not able to reach a definitive histological diagnosis based on WHO criteria.

CONCLUSION

To our knowledge, this is the first report of diffuse histology-proven MCN of the pancreas.

The value of systemic inflammatory markers in identifying malignancy in mucinous pancreatic cystic neoplasms

The treatment decision-making of mucinous pancreatic cystic neoplasm (PCN) has become a common clinical problem since the diagnostic accuracy of current tests in identifying malignancies in pancreatic cysts is limited. In this study, we aimed to validate the predictive value of systemic inflammatory factors in detecting malignant PCNs. Two hundred and forty-five patients with pathologically confirmed mucinous PCNs in a single Chinese institution were retrospectively analyzed. Receiver operating characteristic (ROC) curves were calculated to determine the optimal cut-off values and measure the diagnostic value. The results showed that neutrophil count (P = 0.009), lymphocyte count (P = 0.002), neutrophil-to-lymphocyte ratio (NLR, P < 0.001), platelet-to-lymphocyte ratio (PLR, P < 0.001) and lymphocyte-to-monocyte ratio (LMR, P < 0.001) were distributed differently among the various differentiation groups of PCN. The univariate analyses indicated that a neutrophil count ≥ 2.8 × 10⁹/L (P = 0.024), lymphocyte count ≤ 1.9 × 10⁹/L (P < 0.001), PLR ≥ 125 (P < 0.001), NLR ≥ 1.96 (P < 0.001), and LMR ≤ 4.29 (P < 0.001) were significantly associated with invasive carcinomas in PCN patients. In addition, the multivariate analyses demonstrated that PLR ≥ 125 and LMR ≤ 4.29 were independent predictors of invasive malignancies. The ROC curves exhibited the malignant detection utility of the independent factor-based predictive model with an area under the curve (AUC) of 0.858 (P < 0.001). In conclusion, systemic inflammatory markers provide a supportive and easily accessible tool for the preoperative diagnoses of malignant PCNs.

Nature and management of pancreatic mucinous cystic neoplasm (MCN): A systematic review of the literature

BACKGROUND

The current management of pancreatic mucinous cystic neoplasms (MCN) is defined by the consensus European, International Association of Pancreatology and American College of Gastroenterology guidelines. However, the criterion for surgical resection remains uncertain and differs between these guidelines. Therefore through this systematic review of the existing literature we aimed to better define the natural history and prognosis of these lesions, in order to clarify recommendations for future management.

METHODS

A systematic literature search was performed (PubMed, EMBASE, Cochrane Library) for studies published in the English language between 1970 and 2015.

RESULTS

MCNs occur almost exclusively in women (female:male 20:1) and are mainly located in the pancreatic body or tail (93-95%). They are usually found incidentally at the age of 40-60 years. Cross-sectional imaging and endoscopic ultrasound are the most frequently used diagnostic tools, but often it is impossible to differentiate MCNs from branch duct intraductal papillary mucinous neoplasms (BD-IPMN) or oligocystic serous adenomas pre-operatively. In resected MCNs, 0-34% are malignant, but in those less than 4 cm only 0.03% were associated with invasive adenocarcinoma. No surgically resected benign MCNs were associated with a synchronous lesion or recurrence; therefore further follow-up is not required after resection. Five-year survival after surgical resection of a malignant MCN is approximately 60%.

CONCLUSIONS

Compared to other pancreatic tumors, MCNs have a low aggressive behavior, with exceptionally low rates of malignant transformation when less than 4 cm in size, are asymptomatic and lack worrisome features on pre-operative imaging. This differs significantly from the natural history of small BD-IPMNs, supporting the need to differentiate mucinous cyst subtypes pre-operatively, where possible. The findings support the recommendations from the recent European Consensus Guidelines, for the more conservative management of MCNs.

Are preoperative blood neutrophil-to-lymphocyte and platelet-to-lymphocyte ratios useful in predicting malignancy in surgically-treated mucin-producing pancreatic cystic neoplasms?

INTRODUCTION

The aim of this study was to determine if neutrophil-to-lymphocyte ratio (NLR) and platelet-to-lymphocyte ratio (PLR) were predictive of malignancy in mucin-producing pancreatic cystic neoplasms (MpPCN).

METHODS

One hundred and twenty patients with MpPCN were retrospectively reviewed. Malignant neoplasms were defined as neoplasms harbouring invasive carcinoma or high grade dysplasia. A high NLR and PLR were defined as ≥2.551 and ≥208.1, respectively.

RESULTS

High NLR was significantly associated with symptomatic tumors, larger tumors, solid component, main-duct IPMN, and Sendai high risk category. High PLR was significantly associated with jaundice and Sendai high risk category. On univariate analyses, symptomatic tumors, jaundice, solid component, dilated pancreatic duct, and both a high NLR and PLR were significant predictors of malignant and invasive MpPCN. On multivariate analyses, solid component and dilated pancreatic duct were independent predictors of malignant and invasive MpPCN. PLR was an independent predictor for invasive MpPCN. When MpPCN were stratified by the Fukuoka and Sendai Guidelines, both a high NLR and PLR were significantly associated with malignant neoplasms within the high risk categories.

CONCLUSIONS

PLR is an independent predictor of invasive carcinoma. The addition of PLR as a criterion to the FCG and SCG significantly improved the predictive value of these guidelines in detecting invasive neoplasms.

Evaluation of the Fukuoka Consensus Guidelines for intraductal papillary mucinous neoplasms of the pancreas: Results from a systematic review of 1,382 surgically resected patients

BACKGROUND

International consensus guidelines to guide management of intraductal papillary mucinous neoplasms (IPMN) were revised in Fukuoka and published in 2012. However, despite widespread acceptance of the Fukuoka Consensus Guidelines (FCG), the utility of these guidelines have not been well-validated. This systematic review was performed to evaluate the clinical utility of the FCG.

DESIGN

A computerized search of the PubMed and Scopus databases was performed to identify all studies evaluating the utility of the FCG in surgically resected IPMN. IPMN were stratified according to the FCG as high risk (HR), worrisome risk (WR), and low risk (LR). HR and WR IPMN were termed FCG+ve and LR IPMN were termed FCG-ve.

RESULTS

Seven studies analyzing 1,382 patients were included. There were 402 malignant neoplasms (29%), including 242 invasive IPMNs. There were 1,000 IPMN classified as FCG+ve. The FCG+ve group had a positive predictive value (PPV) ranging from 27 to 62% and the FCG-ve group had negative predictive value ranging from 82 to 100%. Pooled analysis demonstrated that there was 362 of 1,000 (36%) malignant FCG+ve IPMN and 342 of 382 (90%) benign FCG-ve IPMN. PPV of the HR group and the WR groups alone were 104 of 158 (66%) and 75 of 261 (29%), respectively. Forty of 382 (11%), including 22 (6%) invasive FCG-ve IPMN, were malignant. Twenty-six malignant including 18 invasive FCG-ve IPMN were reported from a single study. When the results from this study were excluded, there were only 14 of 241 malignant neoplasms (6%), including 4 of 241 (2%) invasive FCG-ve IPMN in the remaining 6 studies.

CONCLUSION

The FCG+ve criteria had a similarly low PPV compared with the 2006 consensus criteria. Stratification of IPMN into HR and WR groups resulted in a higher PPV in the HR group. Some malignant and even invasive IPMN may be missed by the FCG criteria.

Systematic review and meta-analysis of the spectrum and outcomes of different histologic subtypes of noninvasive and invasive intraductal papillary mucinous neoplasms

BACKGROUND

Our aim was to review the available evidence to determine the clinical importance of the histologic subtypes of noninvasive and invasive intraductal papillary mucinous neoplasms (IPMNs) on disease characteristics and overall survival.

METHODS

We reviewed systematically 14 comparative studies that reported clinicopathologic characteristics and survival of 1,617 patients with IPMN (900 noninvasive and 717 invasive).

RESULTS

The pancreatobiliary subtype was associated with the greatest likelihood of tumor invasion (67.9%; odds ratio [OR], 2.87; 95% CI, 1.90-4.35), harboring an associated mural nodule (56.6%; OR, 2.92; 95% CI, 1.21-7.04), demonstrating tumor recurrence (46.3%; OR, 3.28; 95% CI, 1.41-7.66) and transformation to tubular adenocarcinoma (81.8%; OR, 92.96; 95% CI, 20.76-416.28) among all subtypes. The gastric subtype was associated with the least likelihood of tumor invasion (10.2%; OR, 0.18; 95% CI, 0.13-0.26), association with main duct IPMN (19.2%; OR, 0.12; 95% CI, 0.06-0.26), and tumor recurrence (9.4%; OR, 0.47; 95% CI, 0.26-0.83) among all subtypes. The intestinal subtype had the greatest likelihood of progressing to colloid carcinoma among all subtypes. Tubular adenocarcinoma was associated with an increased risk of vascular invasion (32.9%; OR, 4.86; 95% CI, 1.96-12.01), perineural invasion (54.5%; OR, 2.30; 95% CI, 1.22-4.34), nodal metastasis (52.4%; OR, 3.31; 95% CI, 1.79-6.14), and a positive margin status (17.3%; OR, 8.45; 95% CI, 1.52-46.83). Tubular adenocarcinoma (hazard ratio [HR], 1.90; 95% CI, 1.36-2.67) had a poorer 5-year overall survival compared with colloid carcinoma and was similar to the survival observed in pancreatic ductal adenocarcinoma (HR, 2.00; 95% CI, 1.59-2.52).

CONCLUSION

The prognosis of IPMN depends on its pathologic subtype. Subtype identification should be considered an essential component in future guidelines for the management of IPMN.

Pancreatic cystic neoplasms

Background:

Cystic neoplasms of the pancreas are rare and constitute approximately 0.5% of all pancreatic neoplasms.

Aims:

The study was to describe clinicopathological features of pancreatic cystic tumors.

Patients and Methods:

In our retrospective study, we reviewed 10 cases of pancreatic cystic neoplasms that were diagnosed at the pathology department of Mongi Slim hospital over a 14-year period (2000-2013). We adopted the latest World Health Organization (WHO) classification (2010) in grouping all tumors.

Results:

There were one male and nine female patients (sex ratio M/F = 1:9) aged between 21 and 68 years (mean = 37.5 years). The most common clinical presentation was epigastric and abdominal pain (n = 6) followed by vomiting (n = 3). Abdominal computed tomography (CT) scan disclosed a cystic lesion of the pancreas ranging in size between 2 and 10 cm (mean = 6.75 cm). All patients underwent surgical treatment. Histopathological examination of the surgical specimen established the diagnosis of solid pseudopapillary neoplasm (n = 2), serous cystic neoplasm (n = 2), mucinous cystadenoma (n = 4), mucinous cystadenocarcinoma (n = 1), and intraductal papillary mucinous neoplasm with invasive carcinoma (n = 1).

Conclusion:

Better understanding of pancreatic cystic neoplasms is essential for clinicians to make accurate diagnosis and to provide the best management for patients.

Utility of the sendai consensus guidelines for branch-duct intraductal papillary mucinous neoplasms: a systematic review

INTRODUCTION

The Sendai Consensus Guidelines (SCG) was formulated in 2006 to guide the management of intraductal papillary mucinous neoplasms (IPMN). The main area of controversy is the criteria for selection of branch duct (BD)-IPMN for resection. Although these guidelines have gained widespread acceptance, there is limited data to date supporting its use. This systematic review is performed to evaluate the utility of the Sendai Consensus Guidelines (SCG) for BD-IPMN.

METHODS

Studies evaluating the clinical utility of the SCG in surgically resected neoplasms were identified. The SCG were retrospectively applied to all resected neoplasms in these studies. BD-IPMNs which met the criteria for resection were termed SCG+ve and those for surveillance were termed SCG-ve.

RESULTS

Twelve studies were included, of which, 9 were suitable for pooled analysis. There were 690 surgically resected BD-IPMNs, of which, 24% were malignant. Five hundred one BD-IPMNs were classified as SCG+ve and 189 were SCG-ve. The positive predictive value (PPV) of SCG+ve neoplasms ranged from 11 to 52% and the NPV of SCG-ve neoplasms ranged from 90 to 100%. Overall, there were 150/501 (29.9%) of malignant BD-IPMNs in the SCG+ve group and 171/189 (90%) of benign BD-IPMNs in the SCG-ve group. Of the 18 reported malignant (11 invasive) BD-IPMNs in the SCG-ve group, 17 (including all 11 invasive) were from a single study. When the results from this single study were excluded, 170/171 (99%) of SCG-ve BD-IPMNs were benign.

CONCLUSION

The results of this review confirm the limitations of the SCG for BD-IPMN. The PPV of the SCG in predicting a malignant BD-IPMN was low and some malignant lesions may be missed based on these guidelines.

Systematic review and meta-analysis comparing the surgical outcomes of invasive intraductal papillary mucinous neoplasms and conventional pancreatic ductal adenocarcinoma

OBJECTIVE

The aim of this study was to summarize the current literature comparing the surgical outcomes of invasive intraductal papillary mucinous neoplasms (IPMN(INV)) and conventional pancreatic ductal adenocarcinomas (PDAC) in order to determine the differences in disease characteristics and prognosis.

METHODS

Systematic review of the literature yielded 12 comparative studies reporting the clinicopathological characteristics and overall survival (OS) of 1,450 patients with IPMN(INV) with 19,304 patients with conventional PDAC.

RESULTS

IPMN(INV) had a significantly lower likelihood of tumors extending beyond the pancreas [27.6 vs. 94.3 %; T4 vs. T1: odds ratio (OR) 0.111, 95 % confidence intervals (CI) 0.057-0.214], nodal metastasis (45.4 vs. 62.9 %: OR 0.507, 95 % CI 0.347-0.741), positive margin (14.2 vs. 28.3 %; OR 0.438, 95 % CI 0.322-0.596), perineural invasion (49.2 vs. 76.5 %; OR 0.304, 95 % CI 0.106-0.877) and vascular invasion (25.2 vs. 45.7 % OR 0.417, 95 % CI 0.177-0.980) when compared with PDAC. The 5-year OS of IPMN(INV) was significantly better than PDAC [31.4 vs. 12.4 %: hazard ratio (HR) 0.659, 95 % CI 0.574-0.756]. The tubular subtype had a poorer 5-year OS and demonstrated significantly more aggressive features such as nodal metastases, vascular invasion, and perineural invasion compared with the colloid subtype.

CONCLUSION

IPMN(INV) were significantly more likely to present at an earlier stage and were less likely to demonstrate nodal involvement, perineural invasion and vascular invasion. When controlled for stage, IPMN(INV) had an improved OS when compared with PDAC in the early stages.

Are the Sendai and Fukuoka consensus guidelines for cystic mucinous neoplasms of the pancreas useful in the initial triage of all suspected pancreatic cystic neoplasms? A single-institution experience with 317 surgically-treated patients

BACKGROUND

The Sendai Consensus Guidelines (SCG) were formulated in 2006 and updated in Fukuoka in 2012 (FCG) to guide management of cystic mucinous neoplasms of the pancreas. This study aims to evaluate the clinical utility of the SCG and FCG in the initial triage of all suspected pancreatic cystic neoplasms.

STUDY DESIGN

Overall, 317 surgically-treated patients with a suspected pancreatic cystic neoplasm were classified according to the SCG as high risk (HR(SCG)) and low risk (LR(SCG)), and according to the FCG as high risk (HR(FCG)), worrisome (W(FCG)), and low risk (LR(FCG)). Cystic lesions of the pancreas (CLP) were classified as potentially malignant/malignant or benign according to the final pathology.

RESULTS

The presence of symptoms, proximal lesions with obstructive jaundice, elevated serum carcinoembryonic antigen/carbohydrate antigen 19-9 (CEA/CA 19-9), size ≥3 cm, presence of solid component, main pancreatic duct dilatation, thickened enhancing walls, and change in ductal caliber with distal atrophy were predictive of a potentially malignant/malignant CLP on univariate analyses. The positive predictive value (PPV) and negative predictive value (NPV) of HR(SCG) and HR(ICG2012) for a potentially malignant/malignant lesion was 67 and 88 %, and 88 and 92.5 %, respectively. There were no malignant lesions in both LR groups but some potentially malignant lesions such as cystic pancreatic neuroendocrine neoplasms with uncertain behavior were classified as LR.

CONCLUSION

The updated FCG was superior to the SCG for the initial triage of all suspected pancreatic cystic neoplasms. CLP in the LR(FCG) group can be safely managed conservatively, and those in the HR(FCG) group should undergo resection.

Evaluation of the Sendai and 2012 International Consensus Guidelines based on cross-sectional imaging findings performed for the initial triage of mucinous cystic lesions of the pancreas: a single institution experience with 114 surgically treated patients

BACKGROUND

The Sendai Consensus Guidelines (SCG) were formulated in 2006 to guide the management of mucinous cystic lesions of the pancreas (CLPs) and were updated in 2012 (International Consensus Guidelines, ICG 2012). This study aims to evaluate the clinical utility of the ICG 2012 with the SCG based on initial cross-sectional imaging findings.

METHODS

One hundred fourteen patients with mucinous CLPs were reviewed and classified according to the ICG 2012 as high risk (HR(ICG2012)), worrisome (W(ICG2012)), and low risk (LR(ICG2012)), and according to the SCG as high risk (HR(SCG)) and low risk (LR(SCG)).

RESULTS

On univariate analysis, the presence of symptoms, obstructive jaundice, elevated serum carcinoembryonic antigen (CEA)/carbohydrate antigen (CA)19-9, solid component, main pancreatic duct ≥ 10 mm, and main pancreatic duct ≥ 5 mm was associated with high grade dysplasia/invasive carcinoma in all mucinous CLPs. Increasing number of HR(SCG) or HR(ICG2012) features was associated with a significantly increased likelihood of malignancy. The positive predictive value of HR(SCG) and HR(ICG2012) for high grade dysplasia/invasive carcinoma was 46% and 62.5% respectively. The negative predictive value of both LR(SCG) and LR(ICG2012) was 100%.

CONCLUSION

Both the guidelines were useful in the initial cross-sectional imaging evaluation of mucinous CLPs. The ICG 2012 guidelines were superior to the SCG guidelines.

Use of F-18 fluorodeoxyglucose positron emission tomography with dual-phase imaging to identify intraductal papillary mucinous neoplasm

BACKGROUND & AIMS

We investigated the usefulness of dual-phase F-18 fluorodeoxyglucose positron emission tomography with computed tomography (FDG-PET/CT) to differentiate benign from malignant intraductal papillary mucinous neoplasms (IPMNs) and to evaluate branch-duct IPMNs.

METHODS

We used FDG-PET/CT to evaluate IPMNs in 48 consecutive patients who underwent surgical resection from May 2004 to March 2012. IPMNs were classified as benign (n = 16) or malignant (n = 32) on the basis of histology analysis. The ability of FDG-PET/CT to identify branch-duct IPMNs was compared with that of the International Consensus Guidelines.

RESULTS

The maximum standardized uptake value (SUVmax) was higher for early-phase malignant IPMNs than that for benign IPMNs (3.5 ± 2.2 vs 1.5 ± 0.4, P < .001). When the SUVmax cutoff value was set at 2.0, early-phase malignant IPMNs were identified with 88% sensitivity, specificity, and accuracy. The retention index values for malignant and benign IPMNs were 19.6 ± 17.8 and -2.6 ± 12.9, respectively. When the SUVmax cutoff was set to 2.0 and the retention index value to -10.0, early-phase malignant IPMNs were identified with 88% sensitivity, 94% specificity, and 90% accuracy. In identification of branch-duct IPMNs, when the SUVmax cutoff was set to 2.0, the sensitivity, specificity, and accuracy values were 79%, 92%, and 84%, respectively. By using a maximum main pancreatic duct diameter ≥7 mm, the Guidelines identified branch-duct IPMNs with greater specificity than FDG-PET/CT. The Guidelines criteria of maximum cyst size ≥30 mm and the presence of intramural nodules identified branch-duct IPMNs with almost equal sensitivity to FDG-PET/CT.

CONCLUSIONS

Dual-phase FDG-PET/CT is useful for preoperative identification of malignant IPMN and for evaluating branch-duct IPMN.

Management of mucinous cystic neoplasms of the pancreas

The purpose of this study was to investigate the actual management of mucinous cystic neoplasm (MCN) of the pancreas. A systematic review was performed in December 2009 by consulting PubMed MEDLINE for publications and matching the key words “pancreatic mucinous cystic neoplasm”, “pancreatic mucinous cystic tumour”, “pancreatic mucinous cystic mass”, “pancreatic cyst”, and “pancreatic cystic neoplasm” to identify English language articles describing the diagnosis and treatment of the mucinous cystic neoplasm of the pancreas. In total, 16 322 references ranging from January 1969 to December 2009 were analysed and 77 articles were identified. No articles published before 1996 were selected because MCNs were not previously considered to be a completely autonomous disease. Definition, epidemiology, anatomopathological findings, clinical presentation, preoperative evaluation, treatment and prognosis were reviewed. MCNs are pancreatic mucin-producing cysts with a distinctive ovarian-type stroma localized in the body-tail of the gland and occurring in middle-aged females. The majority of MCNs are slow growing and asymptomatic. The prevalence of invasive carcinoma varies between 6% and 55%. Preoperative diagnosis depends on a combination of clinical features, tumor markers, computed tomography (CT), magnetic resonance imaging, endoscopic ultrasound with cyst fluid analysis, and positron emission tomography-CT. Surgery is indicated for all MCNs.

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.

Solitary true cyst of pancreas: report of a case and review of literature

CONTEXT

Solitary true cysts of the pancreas in adults are extremely rare, and only few cases have been reported in the literature. The etiology and natural history of these lesions remain unknown, and treatment is not standardized. We describe an additional resected case.

CASE REPORTS

A 55-year-old female who presented to us with a history of heaviness and pain in right upper abdomen for 1 year. CT scan of abdomen showed a large unilocular cyst in the region of the head of the pancreas. The patient underwent pancreatico-duodenectomy with binding pancreaticojejunostomy. The histology of cyst revealed true unilocular pancreatic cyst lined by cuboidal epithelium. She is well after 3 years of follow-up.

CONCLUSIONS

A preoperative work-up alone does not always allow an accurate diagnosis, but it is useful in determining lesion characteristics and guiding therapeutic decision-making. When surgery is indicated, a limited resection is warranted in most cases.

Cystic Neoplasms of the Pancreas: Current Diagnostic Modalities and Management

Cystic neoplasm of the pancreas is a relatively uncommon condition covering a wide spectrum of pathology. The increasing incidence as a result of routine imaging tests in asymptomatic patients presents a diagnostic and therapeutic problem to the clinician. This paper discusses the role of the various investigative modalities in the management of cystic neoplasia of the pancreas. Key words: Frantz tumour, Intraductal papillary mucinous neoplasm, Mucinous cystadenoma, Mucinous cystadenocarcinoma, Mucinous neoplasm of the pancreas, Solid pseudopapillary neoplasm

Cystic pancreatic neuroendocrine neoplasms with uncertain malignant potential: report of two cases

Neuroendocrine tumors of the pancreas (NETP) represent only 1%-2% of all pancreatic neoplasms. They can be classified as functioning or non-functioning, respectively, according to the presence or absence of paraneoplastic syndrome. Case 1 concerned a 70-year-old woman with a cystic lesion of the pancreatic head and body. All tumor markers were negative. The patient underwent a distal pancreatectomy. The histology revealed a well-differentiated endocrine tumor with uncertain malignant potential. Case 2 was a 61-year-old man with chronic polyserositis. The serum tumor markers were negative, while he was strongly positive for intracystic tumor markers carcinoembryonic antigen, carbohydrate antigen (CA) 19-9, and CA 125. The patient underwent a cephalo-pancreatic duodenectomy. The preoperative differential diagnosis of cystic NETP is still a challenge due to the high rate of the nonfunctional variant. Although cystic NETPs are well differentiated, they are still tumors with a malignant potential, and therefore an early diagnosis and radical surgical resection could be associated with a better long-term survival.

Predictors of malignant potential of cystic lesions of the pancreas

BACKGROUND

Cystic lesions of the pancreas (CLP) are a diagnostic dilemma, the correct characterisation of which determines surgical management.

METHODS

From 1995 to 2005, radiology and pathology records were reviewed for the presence of CLP. CLP were divided into three groups; Group 1: Benign, Group 2: Pre-malignant, and Group 3: Malignant.

RESULTS

Seventy-nine of 121 patients were included [Group 1: n=46, Group 2: n=10, Group 3: n=23], with a median age at diagnosis of 68 (31-92) years. The median follow-up period was 24 (14-84) months. On univariate analysis, female gender (p=0.04), jaundice (p<0.01), raised serum ALT concentration (p=0.03), cyst size (> or = 2.5 cm) (p<0.01), and biliary duct dilatation (p<0.01) were associated with malignant potential. Benign cysts were more likely to present incidentally (p<0.01). On multi-variate analysis, cyst size (> or =2.5 cm) was an independent predictor of malignant potential. Sub-group analysis revealed that cysts <2.5 cm in the head of the pancreas with evidence of biliary obstruction (either abnormal liver function; raised ALT [p=0.01], ALP [p=0.01], total bilirubin [p=0.02], and/or biliary duct dilatation [p<0.01]) were associated with malignant potential.

CONCLUSION

Cyst size > or =2.5 cm on computer tomography imaging was an independent predictor of pre-malignant and malignant pancreatic cysts. Cyst size and the presence of biliary obstruction predict potentially malignant cysts of the head of the pancreas, which require surgical management.

[Intraductal papillary mucinous tumor: diagnostic and therapeutic approach]

Primary cystic pancreatic neoplasms are rare tumors, with an approximate prevalence of 10% of cystic pancreatic lesions. Most of these lesions correspond to mucinous cystic neoplasm, serous cystoadenoma and intraductal papillary mucinous tumor (IPMT). IPMT is characterized by diffuse dilatation of the main pancreatic duct and/or side branches with inner defects related to mucin or tumor, or mucin extrusion from a patent ampulla. IPMT has a low potential for malignancy, with a low growth rate, a low rate of metastatic spread and postsurgical recurrence. Over the last few years, major advances have been made in the diagnostic and therapeutic management of this tumor.

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.

How useful are clinical, biochemical, and cross-sectional imaging features in predicting potentially malignant or malignant cystic lesions of the pancreas? Results from a single institution experience with 220 surgically treated patients

BACKGROUND

This study aims to determine the use of preoperative clinical, biochemical, and cross-sectional imaging features for predicting malignancy in cystic lesions of the pancreas (CLP).

STUDY DESIGN

Two hundred twenty patients who underwent operations for CLP or suspected CLP were reviewed. Patients were divided into two groups, patients undergoing operations for pseudocysts and patients undergoing operations for suspected cystic neoplasms. The predictive effect of various preoperative factors on the malignant potential of CLP was evaluated.

RESULTS

Forty-four patients with a preoperative diagnosis of pseudocysts underwent operations for complications of pseudocyst. Forty-two were confirmed pathologically to have pseudocysts, but two were found, unexpectedly, to harbor malignant lesions. One hundred seventy-six patients underwent operations for suspected pancreatic cystic neoplasms. There were 70 benign, 51 potentially malignant, and 55 malignant CLP. On multivariate analysis, three factors, ie, elevated serum carcinoembryonic antigen (CEA) or carbohydrate antigen 19-9; cyst size > 3 cm; and presence of one or more of three morphologic features, such as solid component; peripheral calcification; and main duct dilation on cross-sectional imaging were independent predictors of malignancy. Presence of two or three of these factors had a positive predictive value of 88% in predicting a premalignant or malignant CLP.

CONCLUSIONS

Most pancreatic pseudocysts can be accurately diagnosed preoperatively. In patients with suspected pancreatic cystic neoplasms, elevated serum CEA or carbohydrate antigen 19-9, cyst size > 3 cm, and presence of suspicious morphologic features on imaging are predictors of potentially malignant or malignant CLP. Patients with a high likelihood of a potentially malignant or malignant lesion based on these three factors should undergo operation without additional investigations.

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.

A review of mucinous cystic neoplasms of the pancreas defined by ovarian-type stroma: clinicopathological features of 344 patients

INTRODUCTION

Despite formal definitions of mucinous cystic neoplasms (MCNs) and intraductal papillary neoplasms (IPMNs) by the World Health Organization (WHO) and Armed Forces Institute of Pathology (AFIP), several controversies with regard to MCNs remain. The aim of this review was to determine the clinicopathological features of MCNs defined by ovarian-type stroma (OS) as proposed by the WHO and AFIP and to compare them with MCNs defined by less stringent criteria.

METHODS

A MEDLINE search was conducted to identify English-language articles on pancreatic MCNs from 1996 to 2005. Twenty-five studies were identified. The studies were divided into 2 groups: group A included 10 studies with 344 patients whereby the presence of OS was a criteria for the diagnosis of MCNs, and group B, included 15 studies comprising 761 patients whereby the presence of OS was not mandatory for the diagnosis of MCNs.

RESULTS

Patients in group A (MCNs as defined by OS) were almost always female (99.7%), with a mean age of 47 (range, 18-95) years. MCNs were located predominantly in the body or tail of the pancreas (94.6%) and had a mean size of 8.7 cm (range, 0.6-35 cm); 76% were symptomatic, 6.8% demonstrated ductal communication, and 27% were malignant. At a mean follow-up of 57.5 (range, 1-264) months and 43 (range, 2-257) months after surgery, 97.9% of benign and 61.9% of malignant neoplasms were disease free, respectively. Patients in group B were older and had a higher proportion of males. Neoplasms were more evenly distributed in the pancreas, were smaller, communicated more frequently with the pancreatic duct, and were composed of a higher proportion of malignant tumors compared with group A. Their clinicopathological features were intermediate between those of group A and patients with IPMN.

CONCLUSION

Pancreatic MCNs with OS have unique and distinct clinicopathological features. MCNs should be defined by the presence of OS, as it is the most reliable way of distinguishing MCNs from IPMN. Adoption of "looser" criteria will result in misclassification of some IPMNs as MCNs.

Cystic pancreatic tumors (CPT): predictors of malignant behavior

BACKGROUND AND OBJECTIVES

Due to widespread use of imaging studies, increasing cystic pancreatic tumor (CPT) cases are being detected. The diagnosis of malignancy in CPT cases requires pancreatectomy. Clinical and laboratory characteristics of CPT may predict underlying malignancy.

METHODS

CPT cases treated between 1994 and 2004 at our institution were included. Pseudocysts were excluded. Serous cystadenoma (SCA), mucinous cystadenoma (MCA), intrapapillary mucinous tumor, cystic endocrine tumor, and lymphoepithelial cysts were classified as benign or pre-malignant. Serous cystadenocarcinoma (SCACA), mucinous cystadenocarcinoma (MCACA), and adenocarcinoma (ACA) were classified as malignant.

RESULTS

Thirty-five patients had histological confirmation. Median age was 65 years. Male/female ratio was higher in malignant group (P = 0.0284). Weight loss and abdominal mass were more prevalent in malignant group (P = 0.042 and 0.028, respectively). Malignant lesions were larger, associated with local invasion (superior mesenteric artery (SMA), superior mesenteric vein (SMV), portal vein (PV) complex or celiac encasement) and CA 19-9 elevation. On univariate analyses, local invasion (P = 0.0029), negative surgical intervention (P = 0.0010), presence of ACA (P = 0.0044), or malignant CPT (P = 0.0018) were associated with shorter survival. On a multivariate analysis, local invasion was associated with shorter survival [Hazard ratio (HR) = 4.322, P = 0.0218], while surgical intervention was associated with improved survival (HR = 0.179, P = 0.0124).

CONCLUSION

Male sex, abdominal mass, weight loss, larger tumor size, local invasion, and elevated CA 19-9 were associated with malignant CPT.

Cystic tumours of the pancreas

Pancreatic carcinoma accounts for the most dismal survival among all malignancies with 5-year survival rates approaching 5%. The reason for this, besides the inherent biologic nature of the disease, is the fact that the patients tend to present late in the disease. We present a review of the current published data on cystic neoplasms of the pancreas, which though rare, constitute an important subgroup of pancreatic neoplasms that have a better prognosis and are potentially curable lesions.

Pancreatic serous oligocystic adenomas: clinicopathologic features and a comparison with serous microcystic adenomas and mucinous cystic neoplasms

INTRODUCTION

The preoperative distinction between serous cystic neoplasms (SCNs) and mucinous cystic neoplasms (MCNs) is essential, as all MCNs are considered malignant or potentially malignant and should be surgically resected, whereas SCNs are almost always benign. However, the radiologic distinction between SCNs and MCNs is frequently difficult especially with serous oligocystic adenoma (SOA), a morphologic variant of SCN, as both SOA and MCN appear on cross-sectional imaging as a solitary macrocystic lesion in the pancreas. We reviewed all SOAs managed at our institution to determine if any clinicopathologic features would prove useful for establishing a preoperative diagnosis.

METHODS

Over a 15-year period, 64 patients with a pathologically confirmed diagnosis of a pancreatic cystadenoma or cystadenocarcinoma treated at Singapore General Hospital were retrospectively reviewed. There were 27 MCNs and 37 SCNs including 12 SOAs. In addition, 40 cases of SOA previously reported in the literature were reviewed and analyzed together with the 12 patients, making this a series of 52 SOAs.

RESULTS

In our experience, SOAs comprised 32.4% of the SCNs, and females predominated (7/12). The median age of the patients was 42.5 years (range 22-74 years), and only 4 of the 12 patients were symptomatic. Most of the cysts were located in the body or tail of the pancreas (9/12), and the median cyst size was 52.5 mm (range 10-190 mm). When the clinicopathologic features of SOAs and serous microcystic adenomas (SMAs) were compared, there was no difference between the patients with SOAs and SMAs in terms of age, sex, presence of symptoms, cyst size, or site of the lesion. However, SOAs occurred in the women less frequently (67.3% vs. 96.3%, P=0.004), were smaller [40 mm (range 10-190 mm) vs. 95 mm (range 25-180 mm), P<0.001], and occurred more commonly in the head of the pancreas [25 (48.1%) vs. 2(7.4%)] compared to MCNs. None of the SOAs were frankly malignant compared to the 29.6% of MCNs that were.

CONCLUSIONS

SOAs and SMAs have similar clinicopathologic features. On the other hand, SOAs differ from MCNs by their relatively higher male/female ratio, higher frequency of tumors occurring in the head of the pancreas, and smaller cyst size. Knowledge of these distinguishing clinical features when used in combination with other diagnostic modalities such as endoscopic ultrasonography/fine-needle aspiration will enable clinicians to better differentiate these two pathologic entities preoperatively.

Clinicopathological features of patients with concomitant intraductal papillary mucinous neoplasm of the pancreas and pancreatic endocrine neoplasm

BACKGROUND/AIMS

The occurrence of concomitant pancreatic endocrine neoplasm (PEN) and intraductal papillary neoplasm (IPMN) of the pancreas has rarely been reported. We describe our experience with 3 patients with this association and review the existing literature.

METHODS

From 1990 to 2005, 65 patients who underwent surgery for a PEN or IPMN were retrospectively reviewed. Forty-three patients had a PEN, 19 had an IPMN and 3 had both an IPMN and PEN. The 3 patients with concomitant IPMN and PEN are the focus of the current study and their clinicopathological features are reported together with 7 patients previously reported in the literature.

RESULTS

There were 10 patients with a median age of 62 years (range 40-73). The male:female ratio was equal. Seven of 10 patients were symptomatic and the most common symptoms were abdominal pain (n = 5), jaundice (n = 2) and loss of weight (n = 2). The median size of the endocrine neoplasms was 14 mm (range 2-30) and they occurred in the head (n = 3), body (n = 2) and tail (n = 5). Seven of the PENs were classified as benign, 2 were potentially malignant, and 1 was frankly malignant with lymph node involvement. None of the endocrine neoplasms were functioning. The IPMNs were found in the tail (n = 4), head (n = 3), head and body (n = 1), body (n = 1) and the entire pancreas (n = 1). Five of these neoplasms were benign, 2 were borderline and 3 were malignant (1 carcinoma in situ).

CONCLUSION

The occurrence of concomitant IPMN and PEN is more frequent than would be expected. However, it is difficult in the present analysis to determine if this association is more than just fortuitous.

Intraductal papillary-mucinous neoplasms and mucinous cystic neoplasms of the pancreas differentiated by ovarian-type stroma

BACKGROUND

Intraductal papillary-mucinous neoplasms (IPMN) and mucinous cystic neoplasms (MCN) of the pancreas have similar clinicopathologic findings. This study was intended to clarify clinicopathologic characteristics in IPMNs and MCNs differentiated by ovarian-type stroma.

METHODS

Medical records for 77 patients with pancreatic cystic neoplasms with mucin secretion were reviewed. Patients were divided into IPMN (n = 70) or MCN (n = 7) according to the presence of ovarian-type stroma, and clinicopathologic parameters were compared between groups.

RESULTS

IPMNs consisted of 32 adenomas, 12 borderline neoplasms, 13 adenocarcinomas in situ, and 13 invasive adenocarcinomas; MCNs included 6 adenomas and 1 invasive adenocarcinoma. The mean age of IPMN patients (66 years) was significantly older than that of MCN patients (55 years). The male:female ratio in IPMN (53/17) was significantly greater (P < .001) than in MCN (0/7). The location of the pancreatic mass differed, with 76% 0f IPMNs occurring in the head, while 86% of MCNs occurred in the body or tail. Mass mean size was significantly smaller (28 mm vs 78 mm, P < .001), and mean diameter of the main pancreatic duct was larger (6.8 mm vs 3.1 mm, P < .001) in IPMN than in MCN. Patulous papilla was present in 44% (31/70) of IPMNs, but none was present in MCNs. Communication between the cyst and main pancreatic duct was more frequent in IPMNs (67/70) than in MCNs (1/7). Overall 5-year survival rates were 84% (IPMN) and 100% (MCN).

CONCLUSIONS

Clinicopathologic differences between IPMN and MCN are much clearer when differentiated by presence of ovarian-type stroma. Favorable prognosis for both neoplasms is offered by complete resection.

Cystic lesions of the pancreas: an appraisal of an aggressive resectional policy adopted at a single institution during 15 years

BACKGROUND

Although an aggressive resectional approach toward pancreatic cysts has been advocated in the past, many clinicians now deem this therapeutic strategy impractical given the rapidly increasing incidence of incidentally detected pancreatic cystic lesions. The aim of this study was to review the aggressive resectional policy toward pancreatic cysts adopted at our institution during the past 15 years.

METHODS

One hundred nine consecutive patients who underwent surgical resection of a cystic lesion of the pancreas during a 15-year period were retrospectively reviewed. To determine subsets of patients at lower risk of having a malignant cyst, the clinicopathologic features (in particular, the malignant potential) of these patients were compared as a function of 3 variables, ie, presence of symptoms, patient age, and cyst size, using univariate analyses. Results were expressed as median and range and P < .05 was considered statistically significant.

RESULTS

Forty-three (39%) of 109 patients were asymptomatic. Incidental cysts were smaller (28 [10 to 240] vs 59 [10 to 200] mm, P < .001) and were found in older patients (55.0 [18 to 77] vs 45.5 [14 to 82] years, P = .003). Overall, 14% of asymptomatic cysts, versus 35% of symptomatic cysts, were malignant (P = .016). Incidental cysts were also less likely to be premalignant or malignant compared with symptomatic cysts (47% vs 70%, P = .015). Twenty (18%) patients were elderly (73.0 [70 to 82] years old). Elderly patients had a more equal sex distribution (45% vs 76% female, P = .005) and had smaller cysts (26 [10 to 200] vs 55 [10 to 240] mm, P = .003) that involved the head of the pancreas more frequently (8 [40%] vs 17 [19%], P = .045) compared with their younger counterparts. The cohort of elderly patients also had a higher median American Society of Anesthesiologists score (2 [1 to 3] vs 1 [1 to 3], P < .001), and a higher proportion had undergone a "more" major procedure (Whipple's or total pancreatectomy) (55% vs 18%, P < .001). Not unexpectedly, surgical morbidity in the elderly was significantly higher (10 [50%] vs 24 [27%], P = .045). The operative mortality in both groups was not significantly different (1 [5%] vs 1 [1%], P = .324). The proportion of premalignant or malignant lesions in elderly patients was also similar to that in younger patients (11 [55%] vs 55 [62%], P = .574). The size of a cyst in asymptomatic patients had no correlation with its potential for malignancy.

CONCLUSIONS

Reliance on preoperative characteristics alone such as the presence of symptoms, cyst size, and patient age are not sufficiently reliable in determining the malignant potential and thus management approach toward pancreatic cysts.

Estrogen receptors in pancreatic tumors

OBJECTIVES

Although a potential role for estrogen receptors (ER) in pancreatic tumors has been debated for many years, the importance of the receptors in these neoplasms remains unknown. Even the expression of the 2 ER isoforms, ER-alpha and ER-beta, in histological subtypes of pancreatic neoplasms is controversial. The aim of the present study was to systematically review the available literature about ER expression in pancreatic tumors and to discuss the potential importance of estrogen signaling in them.

METHODS

We performed a comprehensive literature search and analyzed the results regarding ER expression in pancreatic tumors, with special emphasis on the specificity of the antibodies used for immunohistochemistry.

RESULTS

Many articles have been published investigating the expression of ERs in pancreatic tumors, but the results are inconsistent. Moreover, most studies used antibodies that detected only ER-alpha, not ER-beta. Thus, the expression pattern of ER-beta in pancreatic neoplasm remains especially unclear.

CONCLUSIONS

The lack of detailed studies evaluating the expression of both ER-alpha and ER-beta receptors using isoform-specific antibodies likely contributes to the inconsistency of published results concerning ER expression in pancreatic tumors. Available published evidence suggests that a thorough reexamination of the potential role of ERs in pancreatic neoplasms is warranted.

Human pancreatic mucinous cystadenoma is characterized by distinct mucin, cytokeratin and CD10 expression compared with intraductal papillary-mucinous adenoma

AIMS

To examine cytokeratin, epithelial glycoprotein (mucin) and glycoprotein CD10 expression in benign mucinous cystdenomas (MCAs) in comparison with intraductal papillary mucinous adenomas (IPMAs).

METHODS AND RESULTS

Thirty MCAs of the pancreas were analysed for immunohistochemical expression of cytokeratin (CK) 7, CK20, MUC1, MUC2, MUC5AC and CD10 and were compared with 16 IPMAs. CK7 was expressed in all neoplasms. CK20 was significantly more frequent in MCAs compared with IPMAs (56.66% versus 18.75%, P = 0.027). MUC1 was more frequent in MCAs (40% versus 12.5%, P = 0.0915), whereas MUC5AC was significantly less frequent in MCAs (33.33% versus 100%). MUC2 was expressed in goblet cells of seven MCAs. In MCAs, CD10 was observed both in epithelial cells and in the ovarian-type stromal cells (24/30). Epithelial expression of CD10 was significantly lower in IPMAs (66.66% versus 6.25%, p = 0.0001).

CONCLUSIONS

MCA is characterized by a significantly greater frequency of expression of CK20 and CD10 when compared with IPMA, which preferentially expresses MUC5AC.

NON-NEOPLASTIC CYSTIC AND CYSTIC-LIKE LESIONS OF THE PANCREAS: MAY MIMIC PANCREATIC CYSTIC NEOPLASMS

BACKGROUND

Cystic lesions of the pancreas consist of a broad range of pathological entities. With the exception of the pancreatic pseudocyst, these are usually caused by pancreatic cystic neoplasms. Non-neoplastic pancreatic cystic and cystic-like lesions are extremely rare. In the present article, the surgical experience with these unusual entities over a 14-year period is reported.

METHODS

Between 1991 and 2004, all patients who underwent surgical exploration for a cystic lesion of the pancreas were retrospectively reviewed. Patients with a pancreatic pseudocyst were excluded. There were 106 patients of whom 8 (7.5%) had a final pathological diagnosis consistent with a non-neoplastic pancreatic cystic or cystic-like lesion, including 3 patients with a benign epithelial cyst, 2 with a pancreatic abscess (one tuberculous and one foreign body), 2 with mucous retention cysts and 1 with a mucinous non-neoplastic cyst. These eight patients are the focus of this study.

RESULTS

There were six female and two male patients with a median age of 61.5 years (range, 41-71 years). All the patients were of Asian origin including seven Chinese and one Indian. Four of the patients were asymptomatic and their pancreatic cysts were discovered incidentally on radiological imaging for other indications. All the patients underwent preoperative radiological investigations, including ultrasonography, computed tomography or magnetic resonance imaging, which showed a cystic lesion of the pancreas. Three patients, all of whom were symptomatic, were diagnosed preoperatively with a malignant cystic neoplasm on the basis of radiological imaging. Two patients were eventually found to have a pancreatic abscess, one tuberculous and the other, secondary to foreign body perforation. The third patient was found on final histology to have chronic pancreatitis with retention cysts. The remaining five patients had a preoperative diagnosis of an indeterminate cyst; on pathological examination, they were found to have a benign epithelial (congenital) cyst (n = 3), retention cyst (n = 1) and mucinous non-neoplastic cyst (n = 1). At a median follow up of 20 months (range, 3-34 months), none of the patients had any evidence of recurrent disease.

CONCLUSION

Non-neoplastic cystic and cystic-like lesions of the pancreas are rare causes of pancreatic cystic lesions that are generally benign and do not require surgery when asymptomatic. However, despite advances in diagnostic investigations such as endoscopic ultrasound with fluid aspirate and magnetic resonance imaging, the preoperative diagnosis remains unreliable. Hence, the challenge for all clinicians is to recognize these lesions preoperatively and to avoid 'unnecessary' surgery.

Clinico-pathological features of cystic pancreatic endocrine neoplasms and a comparison with their solid counterparts

AIM

Pancreatic endocrine neoplasms (PENs) may occasionally manifest as cystic lesions of the pancreas. The aim of this study is to report our experience with cystic PENs and to compare their clinico-pathological features with their solid counterparts.

MATERIALS AND METHODS

From 1990 to 2004, 38 patients with PENs were reviewed. Six of these tumours appeared on radiological imaging as a cystic lesion of the pancreas.

RESULTS

Of the 38 patients with a PEN, 21 of the patients were female and with a median age of 54.5 (range, 33-83) years. Sixteen patients had functional endocrine tumours of which insulinoma was the most common. The six patients with cystic PEN had a median age of 55.5 (range, 41-70) years and half were female. Cystic PENs were significantly larger [48 (range, 25-170) mm vs 19 (range, 3-120) mm, P = 0.013] and were less likely to be benign (0 vs 50%, P = 0.017) compared to their solid counterparts. There was no difference between cystic and solid PENs in terms of age, sex, presence of symptoms, proportion of functioning tumours and location of tumours within the pancreas.

CONCLUSION

Cystic PENs share many clinico-pathological features with solid PENs. These differ only in the cystic appearance and tend to be of a larger size. Hence, these findings suggest that cystic and solid PENs are unlikely to be distinct pathological entities but are likely to be morphological variants of the same entity.

Synchronous pancreatic serous cystic tumor, intraductal papillary mucinous tumor and gastric carcinoma: report of a case

Synchronous cystic tumors of the pancreas are rarely reported in the literature. We report an unusual case of synchronous pancreatic serous cystic tumor (SCT) and intraductal pancreatic mucinous tumor (IPMT) with concomitant gastric carcinoma. This study highlights the importance of careful intra-operative and pathologic examination for concomitant pancreatic neoplasms.