Invasive carcinoma derived from the nonintestinal type intraductal papillary mucinous neoplasm of the pancreas has a poorer prognosis than that derived from the intestinal type. Surgery. 2010;147:812-817. [PMID: 20060146 DOI: 10.1016/j.surg.2009.11.011]

Pancreatic cystic neoplasms: management and unanswered questions

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

Decision making for pancreatic resection in patients with intraductal papillary mucinous neoplasms

AIM: To identify a practical approach for preoperative decision-making in patients with intraductal papillary mucinous neoplasms (IPMNs) of the pancreas.

METHODS: Between March 1999 and November 2006, the clinical characteristics, pathological data and computed tomography/magnetic resonance imaging (CT/MRI) of 54 IPMNs cases were retrieved and analyzed. The relationships between the above data and decision-making for pancreatic resection were analyzed using SPSS 13.0 software. Univariate analysis of risk factors for malignant or invasive IPMNs was performed with regard to the following variables: carcinoembryonic antigen, carbohydrate antigen 19-9 (CA19-9) and the characteristics from CT/MRI images. Receiver operating characteristic (ROC) curve analysis for pancreatic resection was performed using significant factors from the univariate analysis.

RESULTS: CT/MRI images, including main and mixed duct IPMNs, tumor size > 30 mm or a solid component appearance in the lesion, and preoperative serum CA19-9 > 37 U/mL had good predictive value for determining pancreatic resection (P < 0.05), but with limitations. Combining the above factors (CT/MRI images and CA19-9) improved the accuracy and sensitivity for determining pancreatic resection in IPMNs. Using ROC analysis, the area under the curve reached 0.893 (P < 0.01, 95%CI: 0.763-1.023), with a sensitivity, specificity, positive predictive value and negative predictive value of 95.2%, 83.3%, 95.2% and 83.3%, respectively.

CONCLUSION: Combining preoperative CT/MRI images and CA19-9 level may provide useful information for surgical decision-making in IPMNs.

Adjuvant chemotherapy seems beneficial for invasive intraductal papillary mucinous neoplasms

AIMS

The incidence of intraductal papillary mucinous neoplasm (IPMN) is rising and these neoplasms now represent up to 25% of resected pancreatic neoplasms. The optimal postoperative management of resected invasive IPMN is still debated in the absence of large prospective clinical trials and of validated prognostic factors in this setting. The objective of our study was to identify potential prognostic factors and to investigate the role of adjuvant therapies for patients radically resected for invasive IPMN.

METHODS

We retrospectively reviewed clinical and pathological data regarding a large series of patients with invasive IPMN who underwent surgical resection in the last six years at University Hospital of Pisa.

RESULTS

Sixty-four patients were considered for the analysis, thirty-three of whom received adjuvant chemotherapy with gemcitabine. In our series node involvement and high tumoral grade emerged as the major pathologic prognostic factors. Patients treated with adjuvant chemotherapy with gemcitabine experienced a longer disease-free survival than those who received surgery alone.

CONCLUSIONS

Gemcitabine-based chemotherapy seems beneficial as adjuvant treatment for patients with resected invasive IPMN.

Intracholecystic papillary-tubular neoplasms (ICPN) of the gallbladder (neoplastic polyps, adenomas, and papillary neoplasms that are ≥1.0 cm): clinicopathologic and immunohistochemical analysis of 123 cases

The literature on the clinicopathologic characteristics of tumoral intraepithelial neoplasms (neoplastic polyps) of the gallbladder (GB) is fairly limited, due in part to the variability in definition and terminology. Most reported adenomas (pyloric gland type and others) were microscopic and thus regarded as clinically inconsequential, whereas papillary in situ carcinomas have been largely considered a type of invasive adenocarcinoma under the heading of "papillary adenocarcinomas." In this study, 123 GB cases that have a well-defined exophytic preinvasive neoplasm measuring ≥1 cm were analyzed. The patients were predominantly female (F/M=2:1) with a mean age of 61 y and a median tumor size of 2.2 cm. Half of the patients presented with pain, and in the other half the neoplasm was detected incidentally. Other neoplasms, most being gastrointestinal tract malignancies, were present in 22% of cases. Gallstones were identified in only 20% of cases. Radiologically, almost half were diagnosed as "cancer," roughly half with polypoid tumor, and in 10% the lesion was missed. Pathologic findings: (1) The predominant configuration was papillary in 43%, tubulopapillary in 31%, tubular in 26%. (2) Each case was assigned a final lineage type on the basis of the predominant pattern (>75% of the lesion) on morphology, and supported with specific immunohistochemical cell lineage markers. The predominant cell lineage could be identified as biliary in 50% (66% of which were MUC1), gastric foveolar in 16% (all were MUC5AC), gastric pyloric in 20% (92% MUC6), intestinal in 8% (100% CK20; 75% CDX2; 50%, MUC2), and oncocytic in 6% (17% HepPar and 17% MUC6); however, 90% of cases had some amount of secondary or unclassifiable pattern and hybrid immunophenotypes. (3) Of the cases that would have qualified as "pyloric gland adenoma," 21/24 (88%) had at least focal high-grade dysplasia and 18% had associated invasive carcinoma. Conversely, 8 of 47 "papillary adenocarcinoma"-type cases displayed some foci of low-grade dysplasia, and 15/47 (32%) had no identifiable invasion. (4) Overall, 55% of the cases had an associated invasive carcinoma (pancreatobiliary type, 58; others, 10). Factors associated significantly with invasion were the extent of high-grade dysplasia, cell type (biliary or foveolar), and papilla formation. Among systematically analyzed invasive carcinomas, tumoral intraepithelial neoplasia was detected in 6.4% (39/606). (5) The 3-year actuarial survival was 90% for cases without invasion and 60% for those associated with invasion. In contrast, those associated with invasion had a far better clinical outcome compared with pancreatobiliary-type GB carcinomas (3-yr survival, 27%), and this survival advantage persisted even with stage-matched comparison. Death occurred in long-term follow-up even in a few noninvasive cases (4/55; median 73.5 mo) emphasizing the importance of long-term follow-up. In conclusion, tumoral preinvasive neoplasms (≥1 cm) in the GB are analogous to their pancreatic and biliary counterparts (biliary intraductal papillary neoplasms, pancreatic intraductal papillary mucinous neoplasms, and intraductal tubulopapillary neoplasms). They show variable cellular lineages, a spectrum of dysplasia, and a mixture of papillary or tubular growth patterns, often with significant overlap, warranting their classification under 1 unified parallel category, intracholecystic papillary-tubular neoplasm. Intracholecystic papillary-tubular neoplasms are relatively indolent neoplasia with significantly better prognosis compared with pancreatobiliary-type GB carcinomas. In contrast, even seemingly innocuous examples such as those referred to as "pyloric gland adenomas" can progress to carcinoma and be associated with invasion and fatal outcome.

[Pathology and classification of intraductal papillary mucinous neoplasms of the pancreas]

Intraductal papillary mucinous neoplasms (IPMN) are precursor lesions of ductal adenocarcinoma of the pancreas and one of the most common cystic entities in this organ. Branch and main duct types are further distinguished based on the tumor localization. An additional classification is based on the predominant architecture and immunohistochemical profile with four prognostic relevant subtypes, gastric, intestinal, pancreato-biliary and oncocytic. This review provides an overview about the malignant potential of the different subtypes and the prognosis of associated invasive tumors and gives recommendations for the pathological assessment of resection specimens with IPMNs.

[Intraductal papillary mucinous neoplasia: which findings support observation?]

On abdominal CT scans asymptomatic cystic lesions of the pancreas are accidentally detected in 1-2% of patients. Congenital cysts and pancreatic pseudocysts account for two thirds of these lesions. Pancreatic pseudocysts are a frequent complication of acute and chronic pancreatitis. Among resected cystic neoplasms serous cystic adenoma accounts for 30%, mucinous cystic neoplasms for 45% and intraductal papillary mucinous neoplasms for 25%. The diagnosis of a cystic pancreatic lesion is usually made by diagnostic imaging. Symptomatic lesions require definitive therapeutic treatment after appropriate diagnostic work-up. In the diagnosis of asymptomatic cystic lesions several factors are important, among them whether the cyst is connected to the pancreatic duct (as in IPMN and pseudocysts), the size of lesion (for treatment indications) and whether nodules form in the wall of the cyst (a sign of potential malignancy). EUS-guided fine needle aspiration of the cyst fluid adds to the discrimination between benign, premalignant and malignant cystic lesions. Measuring lipase activity, CEA, viscosity and mucin as well as cytology can help in differentiating cystic lesions. An algorithm is discussed for the differential diagnosis and for selection of the appropriate treatment for pancreatic cystic lesions, most of which never require surgery.

Diagnostic significance of a dilated orifice of the duodenal papilla in intraductal papillary mucinous neoplasm of the pancreas

BACKGROUND

A dilated orifice of the duodenal papilla found during screening endoscopy or ERCP is well-known as one of the specific findings of intraductal papillary mucinous neoplasm (IPMN). However, its clinical significance is still unclear.

OBJECTIVE

To assess the diagnostic significance of a dilated orifice of the duodenal papilla and evaluate whether this could be a factor predictive of malignancy or a subtype of IPMN.

DESIGN

Retrospective study.

SETTING

University hospital.

PATIENTS

This study involved 149 patients who underwent pancreatectomy for IPMN between January 1987 and June 2011.

INTERVENTION

ERCP.

MAIN OUTCOME MEASUREMENTS

The rate of malignant and intestinal type IPMNs in patients with and without papillary dilation.

RESULTS

A dilated orifice of the duodenal papilla was significantly associated with intestinal type IPMN (P < .001), but this finding could not predict the malignant grade of IPMN (P = .13). Multivariate analysis revealed that a dilated orifice was a significant factor for predicting intestinal type in both main duct (P = .01) and branch duct IPMNs (P < .001).

LIMITATIONS

The validity of the definition of papillary dilation, selection bias, and a retrospective study.

CONCLUSION

A dilated orifice of the duodenal papilla could be a significant factor for predicting intestinal type IPMN. This may lead to better clinical management of patients with IPMN.

International consensus guidelines 2012 for the management of IPMN and MCN of the pancreas

The international consensus guidelines for management of intraductal papillary mucinous neoplasm and mucinous cystic neoplasm of the pancreas established in 2006 have increased awareness and improved the management of these entities. During the subsequent 5 years, a considerable amount of information has been added to the literature. Based on a consensus symposium held during the 14th meeting of the International Association of Pancreatology in Fukuoka, Japan, in 2010, the working group has generated new guidelines. Since the levels of evidence for all items addressed in these guidelines are low, being 4 or 5, we still have to designate them "consensus", rather than "evidence-based", guidelines. To simplify the entire guidelines, we have adopted a statement format that differs from the 2006 guidelines, although the headings are similar to the previous guidelines, i.e., classification, investigation, indications for and methods of resection and other treatments, histological aspects, and methods of follow-up. The present guidelines include recent information and recommendations based on our current understanding, and highlight issues that remain controversial and areas where further research is required.

Lateral approach for laparoscopic splenic vessel-preserving distal pancreatectomy

AIM

We sought to evaluate the feasibility of the lateral approach for laparoscopic splenic vessel-preserving distal pancreatectomy (LA-SVPDP).

BACKGROUND

Complete preservation of the splenic vessels is an ideal outcome in spleen-preserving distal pancreatectomy (SPDP). However, the preservation of the vessels is challenging in laparoscopic surgery because the splenic vein is often embedded in the pancreatic parenchyma. Herein we have described LA-SVPDP, the most feasible method for laparoscopic SPDP, and the outcome of our initial experience.

PATIENTS

Twenty-three patients underwent laparoscopic SPDP. Before we adopted LA-SVPDP, 8 patients underwent the Warshaw method and 6 underwent SVPDP. After the adoption of LA-SVPDP, 8 patients underwent LA-SVPDP and 1 donor underwent the Warshaw method.

RESULTS

None of patients undergoing LA-SVPDP required conversion to an open operation, whereas 2 patients undergoing the other procedures were converted to open operations. Five out of 8 patients who underwent the Warshaw method showed engorgement of the gastric veins, revealed by computed tomography. However, only 1 of the 5 patients showed mild gastric varices on endoscopy.

CONCLUSION

Although the Warshaw method is acceptable with a low incidence of gastric varices in our analysis, SVPDP is a feasible approach for SPDP. Our LA-SVPDP technique may contribute to safer and easier SVPDP in laparoscopic surgery.

Invasive carcinoma derived from intestinal-type intraductal papillary mucinous neoplasm is associated with minimal invasion, colloid carcinoma, and less invasive behavior, leading to a better prognosis

OBJECTIVES

Although intestinal-type intraductal papillary mucinous carcinoma (IPMC) is reported to have a better prognosis, few studies have addressed its invasive pattern. The meaning of "minimal invasion" (MI) in IPMC also remains unclear. We investigated the prognosis of intraductal papillary mucinous neoplasm (IPMN) focusing on MI and subtypes.

METHODS

We evaluated 71 patients with IPMC among a total of 179 patients with resected IPMN.

RESULTS

Although 2 of 10 MI-IPMC patients had lymph node metastasis, there were no disease-specific deaths among the MI-IPMC patients. Minimally invasive IPMCs were more frequently observed in intestinal-type IPMC (23/33 cases) than in non-intestinal-type IPMCs (16/38 cases; P = 0.019). Among 32 patients with massively invasive IPMC, the prognosis was significantly better for patients with intestinal-type IPMC than for patients with non-intestinal-type IPMC (P = 0.013). When confined to massively invasive IPMC, tubular invasion (P < 0.001) and lymphatic (P = 0.001) or serosal (P = 0.021) invasion were less frequently observed in intestinal-type IPMC than in non-intestinal-type IPMC.

CONCLUSIONS

Invasive carcinoma derived from intestinal-type IPMN is associated with MI, colloid carcinoma, and less invasive behavior.

Expression of claudin-4 (CLDN4) mRNA in intraductal papillary mucinous neoplasms of the pancreas

Claudin-4, encoding a protein for tight junction formation and function, is highly overexpressed in pancreatic ductal adenocarcinoma and is also associated with invasive adenocarcinomas arising in intraductal papillary mucinous neoplasms of the pancreas. However, the expression pattern of claudin-4 during neoplastic progression of intraductal papillary mucinous neoplasms remains unknown. Using quantitative real-time reverse transcription-PCR, we analyzed claudin-4 mRNA in a panel of 14 pancreatic cancer cell lines and in formalin-fixed paraffin-embedded tissues from 80 patients with intraductal papillary mucinous neoplasms of different histological grades and papillary subtypes. Increased expression of claudin-4 was confirmed in all the pancreatic cancer cell lines tested as compared with normal ductal epithelial cells and fibroblast cultures. The claudin-4 expression was significantly higher in high-grade intraductal papillary mucinous neoplasms (borderline neoplasm and carcinoma) than in low-grade intraductal papillary mucinous neoplasms (adenoma) (P<0.0001). In addition, claudin-4 mRNA levels were significantly higher in intestinal-type intraductal papillary mucinous neoplasms than in non-intestinal-type intraductal papillary mucinous neoplasms based on papillary subclassification (P<0.0001). Our findings suggest that claudin-4 expression is associated with neoplastic progression of intraductal papillary mucinous neoplasms and, especially, with a distinct pathway to intestinal differentiation.

A history of acute pancreatitis in intraductal papillary mucinous neoplasms of the pancreas is a potential predictive factor for malignant papillary subtype

BACKGROUND/AIMS

There are several reports regarding intraductal papillary mucinous neoplasms (IPMNs) detected after the occurrence of acute pancreatitis. Although the presence of symptoms is regarded as a factor for predicting malignant IPMNs, there have been few reports demonstrating whether a history of acute pancreatitis is a predictor of malignancy. The aim of this study was to evaluate the relationship between a history of acute pancreatitis and clinicopathological features of IPMNs including the papillary subtype.

METHODS

The data of 150 IPMNs resected between 1990 and 2009 were retrospectively reviewed. They were classified into IPMNs with or without history of acute pancreatitis, and then the clinicopathological features were compared between the 2 groups.

RESULTS

Nineteen (13%) of the 150 patients had a history of acute pancreatitis. Nine of them had repeated episodes of pancreatitis; however, severe pancreatitis was uncommon. The diameter of the main pancreatic duct of the pancreatitis group was significantly larger than that of the nonpancreatitis group (p = 0.04). The pancreatitis group had a significantly higher frequency of carcinoma derived from IPMNs than the nonpancreatitis group (p = 0.03). The incidence of intestinal-type IPMNs in the pancreatitis group was significantly higher than that in the nonpancreatitis group (p < 0.001).

CONCLUSION

Acute pancreatitis associated with IPMNs could predict malignant intestinal-type tumor. and IAP.

Controversies in the management of pancreatic IPMN

Although considerable progress has been made in our understanding of intraductal papillary mucinous neoplasm (IPMN) of the pancreas, some issues still remain to be resolved. Uncertainty exists regarding the classification of IPMNs. The necessity of the mixed-type category of IPMN and whether such lesions should be defined radiographically or histologically needs to be determined. The preoperative distinction of branch duct IPMNs from nonmucinous cysts should be further investigated so that potentially malignant lesions can be identified and management strategies guided effectively. The role and safety of cystic fluid analysis remains to be clarified in this context. With regard to the diagnosis of malignancy in branch duct IPMNs, criteria for identifying malignancy need to be re-evaluated. The presence of mural nodules is a very reliable predictor; however, controversy exists over the value of size as a reliable indicator. Criteria with increased specificity are needed, perhaps including histological subtype of lesion, to reduce the false-positive rate of the present criteria. Finally, the best modality and interval for surveillance of branch duct IPMNs requires determination because of its significance in terms of malignant transformation, development of distinct ductal adenocarcinoma and disease recurrence after resection.

Intraductal papillary-mucinous neoplasia of the pancreas: Histopathology and molecular biology

Intraductal papillary-mucinous neoplasm (IPMN) of the pancreas is a clinically and morphologically distinctive precursor lesion of pancreatic cancer, characterized by gradual progression through a sequence of neoplastic changes. Based on the nature of the constituting neoplastic epithelium, degree of dysplasia and location within the pancreatic duct system, IPMNs are divided in several types which differ in their biological properties and clinical outcome. Molecular analysis and recent animal studies suggest that IPMNs develop in the context of a field-defect and reveal their possible relationship with other neoplastic precursor lesions of pancreatic cancer.

Prognosis of invasive intraductal papillary mucinous neoplasms of the pancreas

Intraductal papillary mucinous neoplasms (IPMN) are mucin producing cystic neoplasms of the pancreas histologically classified as having non-invasive and invasive components. The five-year survival rates for non-invasive and associated invasive carcinoma are 90% and 40%, respectively in resected IPMN lesions. Invasive carcinoma within IPMN lesions can be further classified by histological subtype into colloid carcinoma and tubular carcinoma. Estimated five-year survival rates following resection of colloid carcinoma range from 57%-83% and estimated five-year survival following resection of tubular carcinoma range from 24%-55%. The difference in survival outcome between invasive colloid and tubular IPMN appears to be a function of disease biology, as patients with the tubular subtype tend to have larger tumors with a propensity for metastasis to regional lymph nodes. When matched to resected conventional pancreatic adenocarcinoma lesions by the Memorial Sloan Kettering Cancer Center pancreatic adenocarcinoma nomogram, the colloid carcinoma histological subtype has an improved estimated five-year survival outcome compared to conventional pancreatic adenocarcinoma, 87% and 23% (P = 0.0001), respectively. Resected lesions with the tubular carcinoma subtype overall have a similar five-year survival outcome compared to conventional pancreatic adenocarcinoma. However, when these groups were stratified by regional lymph node status patients with negative regional lymph nodes and the tubular subtype experienced significantly better survival than patients with a similar nodal status and ductal adenocarcinoma with estimated five-year survival rates of 73% and 27% (P = 0.01), respectively.

Pancreatic intraepithelial neoplasia-can we detect early pancreatic cancer?

Haugk B
(2010) Histopathology 57, 503-514
Pancreatic intraepithelial neoplasia - can we detect early pancreatic cancer? Pancreatic cancer is one of the most lethal cancers, with an incidence equalling mortality. Pancreatic cancer is a heterogeneous group in which pancreatic ductal adenocarcinoma (PDAC) is the most common. It is now established that PDAC develops through stepwise progression from precursor lesions. Detection and treatment of these precursor lesions would allow curative treatment. Three precursor lesions for PDAC have been identified. Two of these - mucinous cystic neoplasms (MCNs) and intraductal papillary mucinous neoplasms (IPMNs) - are rare, radiologically detectable, cystic precursor lesions which can be cured if treated at the preinvasive stage. The third and most common precursor lesion has recently been defined as pancreatic intraepithelial neoplasia (PanIN). PanINs are microscopic lesions with no clinical correlate. They display a spectrum of cyto-architectural changes (PanIN-1, PanIN-2 and PanIN-3) mirrored in an increasing accumulation of molecular genetic changes, with PanIN-3 sharing many of the alterations with PDAC. Great advances in the understanding of pancreatic carcinogenesis have opened avenues for diagnosis and chemoprevention. However, access to the pancreas is limited, molecular tests are at the early stages and too little is known about the natural history of early PanINs to justify resection. Currently, screening focuses upon high-risk individuals only.