Role of intraoperative cytology combined with histology in detecting continuous and skip type intraductal cancer existence for intraductal papillary mucinous carcinoma of the pancreas

The Role of Intraoperative Pancreatoscopy in the Surgical Management of Intraductal Papillary Mucinous Neoplasms: A Scoping Review

OBJECTIVES

Most patients with intraductal papillary mucinous neoplasms (IPMNs) are diagnosed with a solitary lesion; however, the presence of skip lesions, not appreciable on imaging, has been described. Postoperatively, these missed lesions can continue to grow and potentially become cancerous. Intraoperative pancreatoscopy (IOP) may facilitate detection of such skip lesions in the remnant gland. The aim of this scoping review was to appraise the evidence on the role of IOP in the surgical management of IPMNs.

MATERIALS AND METHODS

Studies reporting on the use of IOP during IPMN surgery were identified through searches of the PubMed, Embase, and Scopus databases. Data extracted included IOP findings, surgical plan modifications, and patient outcomes. The primary outcome of interest was the utility of IOP in surgical decision making.

RESULTS

Ten studies reporting on the use of IOP for IPMNs were identified, representing 147 patients. A total of 46 skip lesions were identified by IOP. Overall, surgical plans were altered in 37% of patients who underwent IOP. No IOP-related complications were reported.

CONCLUSIONS

The current literature suggests a potential role of integration of IOP into the management of patients with IPMNs. This tool is safe and feasible and can result in changes in surgical decision making.

Intraoperative pancreatoscopy in pancreaticoduodenectomy for intraductal papillary mucinous neoplasms of the pancreas: Application to the laparoscopic approach

BACKGROUND

/Purpose: Owing to the characteristics of IPMNs, which have variable skipped lesions along the main pancreatic duct (MPD), determining the surgical margins is very difficult. This study aimed to investigate the efficacy and potential oncologic impact of intraoperative pancreatoscopy (IOP) compared to frozen section biopsy (FSB) in pancreaticoduodenectomy (PD) for pancreatic head IPMNs.

METHODS

Data of patients who underwent PD for IPMNs of the pancreas between October 2007 and May 2020 were retrospectively reviewed. IOP was performed in selected patients with IPMNs with inconclusive MPD involvement based on preoperative evaluations. Patients were divided into two groups, IOP group, FSB group. Clinicopathologic features and oncologic outcomes were compared between two groups.

RESULTS

60 patients underwent PD (laparoscopic or robotic, 42; open, 18) for pancreatic head IPMNs. IOP was safely performed in 28 patients, including minimally invasive approach used in 21 patients (35%). IOP group had a significantly larger MPD size (9.15 ± 4.79 mm vs 6.43 ± 4.11 mm, p = 0.021). Based on IOP, the initial surgical plan could be changed in 5 patients (17.8%) for complete resection. Recurrence occurred in 2 patients in FSB group and 3 patients in IOP group during the follow-up period (33.2 months, [range, 3.5-131.4 months]). Overall disease-free survival rate did not significantly differ between two groups (p = 0.529).

CONCLUSIONS

IOP can be safely performed in patients with pancreatic head IPMNs with MPD dilatation, even in the laparoscopic approach. Further studies evaluating the long-term oncologic effect of IOP for the management of IPMNs are required.

Laparoscopic intraoperative pancreatoscopy for main duct intraductal papillary mucinous neoplasms assessment

Video 1Intraoperative pancreatoscopy during laparoscopic pancreatic resection for main pancreatic duct intraductal papillary mucinous neoplasms.

The Use of Intraoperative Frozen Sections in Guiding the Extent of Pancreatic Resections for Intraductal Papillary Mucinous Neoplasms: A Single Institution Experience and Review of the Literature

OBJECTIVES

The utility of frozen section evaluation of the pancreatic parenchymal resection margin(s) in the surgical management of intraductal papillary mucinous neoplasm (IPMN) remains controversial. We investigated the frequency of its use in IPMN resections and its impact on achievement of negative final parenchymal margin(s).

METHODS

Sixty-two IPMN resections (11 with invasive carcinoma) performed over a 12-year period were studied.

RESULTS

Frozen sections of the parenchymal margin(s) were performed on 44 of the 62 resections (71%), 30 (68%) of which had 10 positive and 22 indefinite margins on frozen section. Additional margin resections were performed in 14 of these 30 cases (47%), boosting the complete resection rate from 14% (2 of 14) on the initial margin(s) to 71% (10 of 14) on the final margin(s) (P = 0.002). Overall, negative final parenchymal margin(s) were achieved more frequently when evaluation of the initial margin(s) by frozen section was performed (35 of 44; 80%) than when it was not (11 of 18; 61%) (P = 0.13).

CONCLUSIONS

In the intraoperative management of IPMN, frozen sections are highly reliable for margin evaluation and are useful for guiding the extent of pancreatic resection.

Indications to total pancreatectomy for positive neck margin after partial pancreatectomy: a review of a slippery ground

The extension of a partial pancreatectomy up to total pancreatectomy because of positive neck margin examined at intraoperative frozen section (IFS) analysis is an accepted procedure in modern pancreatic surgery with good accuracy. The goal of this practice is to improve the rate of radical (R0) resection in malignant tumors, mainly pancreatic ductal adenocarcinoma (PDAC), and to completely resect pre-invasive neoplasms such as intraductal papillary mucinous neoplasms (IPMNs). In the setting of IPMNs there is a consensus for pancreatic re-resection when high-grade dysplasia and invasive cancer are present at the neck margin. The presence of denudation is another indication for further resection in IPMNs. The role of IFS analysis in the management of pancreatic cancer is more debated. The presence of a positive intraoperative transection margin can be considered the surrogate of a biologically aggressive disease associated with a poorer prognosis. There are conflicting data regarding possible advantages of pancreatic re-resection up to total pancreatectomy, and the lack of randomized trials comparing different strategies does not offer a definitive answer. The goal of this review is to provide an up-to-date overview of the role IFS analysis of pancreatic margin and of pancreatic re-resection up to total pancreatectomy considering different pancreatic tumors.

Fate of Patients With Intraductal Papillary Mucinous Neoplasms of Pancreas After Resection According to the Pathology and Margin Status: Continuously Increasing Risk of Recurrence Even After Curative Resection Suggesting Necessity of Lifetime Surveillance

OBJECTIVE

This study evaluated the associated factors and prognosis according to pathology and margin after surgical resection of intraductal papillary mucinous neoplasms (IPMN).

BACKGROUND

There is limited information on recurrence patterns according to pathology and margin in IPMN.

METHODS

Total 577 patients who underwent operation for IPMN at a tertiary center were included. Factors associated with recurrence, survival and recurrence outcomes according to pathology and margin were analyzed.

RESULTS

Among 548 patients analyzed, 353 had low-grade dysplasia (LGD); 78, high-grade dysplasia (HGD); and 117, invasive IPMN. Total 50 patients developed recurrences, with four resection margins, eight remnant pancreas, 11 locoregional, and 35 distant recurrences. Invasive IPMN showed worse 5-year cumulative recurrence risk (LGD vs HGD vs invasive: 0.7% vs 4.3% vs 37.6%, p < 0.001) and 5-year survival rate (89.0% vs 84.0% vs 48.4%, p < 0.001). Recurrence risk increased after 5 years, even in LGD and HGD. Malignant margin (HGD and invasive) had worse 5-year cumulative recurrence rate (R0 vs LGD vs malignant: 8.3% vs 5.9% vs 50.6%, p < 0.001) and 5-year survival rate (80.7% vs 83.0% vs 30.8%, p < 0.001). CA19-9 > 37 (p = 0.003), invasive IPMN (p < 0.001), and malignant margin (p = 0.036) were associated with recurrence.

CONCLUSIONS

Invasive IPMN developed more recurrences and had worse survival than LGD or HGD, indicating the need for more efficient postoperative treatment strategies. Patients with LGD and HGD also need regular follow-up for recurrence after 5 years. Malignant margins need additional resection to achieve negative or at least LGD margin.

Metachronous intraductal papillary mucinous neoplasms disseminate via the pancreatic duct following resection

Metachronous development of intraductal papillary mucinous neoplasms in the remnant pancreas following resection is a significant clinical burden. Our aim was to characterize the clinicopathological and molecular features of the patients with metachronous tumor development to identify predictive factors and the possible route(s) of dissemination. Seventy-four patients who underwent resection of intraductal papillary mucinous neoplasms with no invasive compartment or associated carcinoma were retrospectively analyzed. In patients with metachronous tumor development, targeted sequencing of 18 genes associated with pancreatic tumorigenesis and immunohistochemical detection of four proteins (p53, SMAD4, p16, and β-catenin) were performed on both primary and metachronous tumors. The distributions of microscopic neoplastic lesions were examined at surgical margins and in apparently normal tissue apart from the primary tumor. During the median follow-up period of 52 months, 9 patients (12%) developed metachronous tumors in the remnant pancreas. Primary tumors located in the body/tail of the pancreas (odds ratio, 15; 95% confidence interval, 1.6-131) and of the pancreatobiliary type (odds ratio, 6.1; 95% confidence interval, 1.1-35.7) were identified as significant risk factors for subsequent metachronous tumor development. Eight of the nine patients shared molecular aberrations between their primary and metachronous tumors, suggesting migrations from the primary tumor to the pancreatic duct as the cause of metachronous tumor development. Our data suggest that these post-resection metachronous tumors develop by skip dissemination of the primary tumor, potentially via the pancreatic duct. The development of strategies to better predict and prevent this form of tumor progression is necessary.

European evidence-based guidelines on pancreatic cystic neoplasms

Evidence-based guidelines on the management of pancreatic cystic neoplasms (PCN) are lacking. This guideline is a joint initiative of the European Study Group on Cystic Tumours of the Pancreas, United European Gastroenterology, European Pancreatic Club, European-African Hepato-Pancreato-Biliary Association, European Digestive Surgery, and the European Society of Gastrointestinal Endoscopy. It replaces the 2013 European consensus statement guidelines on PCN. European and non-European experts performed systematic reviews and used GRADE methodology to answer relevant clinical questions on nine topics (biomarkers, radiology, endoscopy, intraductal papillary mucinous neoplasm (IPMN), mucinous cystic neoplasm (MCN), serous cystic neoplasm, rare cysts, (neo)adjuvant treatment, and pathology). Recommendations include conservative management, relative and absolute indications for surgery. A conservative approach is recommended for asymptomatic MCN and IPMN measuring <40 mm without an enhancing nodule. Relative indications for surgery in IPMN include a main pancreatic duct (MPD) diameter between 5 and 9.9 mm or a cyst diameter ≥40 mm. Absolute indications for surgery in IPMN, due to the high-risk of malignant transformation, include jaundice, an enhancing mural nodule >5 mm, and MPD diameter >10 mm. Lifelong follow-up of IPMN is recommended in patients who are fit for surgery. The European evidence-based guidelines on PCN aim to improve the diagnosis and management of PCN.

Risk factor, early diagnosis and overall survival on outcome of association between pancreatic cancer and diabetes mellitus: Changes and advances, a review

To review literature addressing determination of the risk factor, early diagnosis and overall survival on outcome among patient of pancreatic cancer associated with diabetes mellitus from the perspective of pancreatic surgery. To identify recent guidelines, clinical pathogenesis, pathological classification, screening methodology and advances in surgical management. It identifies those clinical and surgical variables to predict excellent prognosis in respect of life style changes, ongoing advancement in therapeutic and surgical treatment and postoperative follow up. Approximately 85% pancreatic cancer have impaired glucose tolerance and may be associated with diabetes mellitus. Diabetes improves following pancreatic resection. This suggest diabetes is caused by pancreatic cancer. New onset glucose intolerance or DM is an earliest manifestation of pancreatic cancer. Recognition of new onset diabetes as an early manifestation of pancreatic cancer leads to diagnosis of asymptomatic, early stage pancreatic cancer. Thus, helps to aid in better diagnosis and therefore prolonging survival rate. Increasing duration of diabetes mellitus is significantly associated with decreasing risk of pancreatic cancer. Elderly patient with new onset diabetes have high risk of having pancreatic cancer compared to general population. New onset hyperglycemia and diabetes serves as an important screening tool to diagnose asymptomatic pancreatic cancer patient and improves pancreatic cancer related survival. DM in association with pancreatic cancer have reduced overall survival rate and increased mortality. Despite of having dismal prognosis of pancreatic cancer, many studies have concluded the survival rate of 5 years. There exists a bidirectional association between pancreatic cancer and DM is found to be a cause of pancreatic cancer as well as complication. The study on pancreatic cancer and diabetes has offered an interesting field of research based study and surgical practices.

Intraductal papillary mucinous neoplasm of the pancreas - epidemiology, risk factors, diagnosis, and management

Intraductal papillary mucinous neoplasm (IPMN) is one of the most common cystic neoplasms of the pancreas. It is a heterogeneous disease and can be divided into ductal types and morphological subtypes. The incidence of IPMN is increasing, likely due to the widespread use of cross-sectional imaging and a growing elderly population. IPMN poses an increasing demand on the health care system. Current guidelines provide indications for surgery and recommendations for surveillance, but management of IPMN is still challenging in routine clinical practice. In this article, we review current knowledge about IPMN and provide future directions for improving diagnosis and management.

Revisions of international consensus Fukuoka guidelines for the management of IPMN of the pancreas

The management of intraductal papillary mucinous neoplasm (IPMN) continues to evolve. In particular, the indications for resection of branch duct IPMN have changed from early resection to more deliberate observation as proposed by the international consensus guidelines of 2006 and 2012. Another guideline proposed by the American Gastroenterological Association in 2015 restricted indications for surgery more stringently and recommended physicians to stop surveillance if no significant change had occurred in a pancreatic cyst after five years of surveillance, or if a patient underwent resection and a non-malignant IPMN was found. Whether or not it is safe to do so, as well as the method and interval of surveillance, has generated substantial debate. Based on a consensus symposium held during the meeting of the International Association of Pancreatology in Sendai, Japan, in 2016, the working group has revised the guidelines regarding prediction of invasive carcinoma and high-grade dysplasia, surveillance, and postoperative follow-up of IPMN. As the working group did not recognize the need for major revisions of the guidelines, we made only minor revisions and added most recent articles where appropriate. The present guidelines include updated information and recommendations based on our current understanding, and highlight issues that remain controversial or where further research is required.

Intraductal Papillary Mucinous Neoplasm of the Pancreas: Current Perspectives

In this article, we aimed to review the literature on the clinics and management of intraductal papillary mucinous neoplasm (IPMN). Intraductal papillary mucinous neoplasm of the pancreas is a mucin-producing cystic mass originating from the pancreatic ductal system. Approximately 25% of the pancreatic neoplasms resected surgically and 50% of pancreatic cysts detected incidentally are IPMNs. They can be benign or malignant in character, while malignant transformation of benign forms can be encountered. It is important to determine IPMNs in the early stages, implementation of appropriate treatment approaches, and follow-up to provide better prognosis. We reviewed the studies published in the English medical literature through PubMed and summarized the clinical features and current approaches to the treatment and follow-up of the IPMN. Due to the recent advances and widespread implementation of radiological imaging techniques, the incidental detection rate of IPMNs has increased significantly. The effective treatment of the disease is possible via the detailed diagnosis of the disease, determination of the prognostic factors, and a multidisciplinary approach. Recent literature also emphasized the molecular profile determination approaches for assessment of prognosis of patients with IPMN. Current knowledge on IPMN, a clinically important epidemiologic problem, shows that the treatment should be personalized considering the prognostic features and life expectancy of the patient.

A Revised Classification System and Recommendations From the Baltimore Consensus Meeting for Neoplastic Precursor Lesions in the Pancreas

International experts met to discuss recent advances and to revise the 2004 recommendations for assessing and reporting precursor lesions to invasive carcinomas of the pancreas, including pancreatic intraepithelial neoplasia (PanIN), intraductal papillary mucinous neoplasm (IPMN), mucinous cystic neoplasm, and other lesions. Consensus recommendations include the following: (1) To improve concordance and to align with practical consequences, a 2-tiered system (low vs. high grade) is proposed for all precursor lesions, with the provision that the current PanIN-2 and neoplasms with intermediate-grade dysplasia now be categorized as low grade. Thus, "high-grade dysplasia" is to be reserved for only the uppermost end of the spectrum ("carcinoma in situ"-type lesions). (2) Current data indicate that PanIN of any grade at a margin of a resected pancreas with invasive carcinoma does not have prognostic implications; the clinical significance of dysplasia at a margin in a resected pancreas with IPMN lacking invasive carcinoma remains to be determined. (3) Intraductal lesions 0.5 to 1 cm can be either large PanINs or small IPMNs. The term "incipient IPMN" should be reserved for lesions in this size with intestinal or oncocytic papillae or GNAS mutations. (4) Measurement of the distance between an IPMN and invasive carcinoma and sampling of intervening tissue are recommended to assess concomitant versus associated status. Conceptually, concomitant invasive carcinoma (in contrast with the "associated" group) ought to be genetically distinct from an IPMN elsewhere in the gland. (5) "Intraductal spread of invasive carcinoma" (aka, "colonization") is recommended to describe lesions of invasive carcinoma invading back into and extending along the ductal system, which may morphologically mimic high-grade PanIN or even IPMN. (6) "Simple mucinous cyst" is recommended to describe cysts >1 cm having gastric-type flat mucinous lining at most minimal atypia without ovarian-type stroma to distinguish them from IPMN. (7) Human lesions resembling the acinar to ductal metaplasia and atypical flat lesions of genetically engineered mouse models exist and may reflect an alternate pathway of carcinogenesis; however, their biological significance requires further study. These revised recommendations are expected to improve our management and understanding of precursor lesions in the pancreas.

Long-term outcomes after total pancreatectomy: special reference to survivors' living conditions and quality of life

BACKGROUND

Although recent studies have confirmed the safety of total pancreatectomy (TP), appropriate selection of patients for TP has not been well documented. Because patients require lifelong medical treatment and self-management of pancreatic insufficiency after TP, indications for TP should be determined carefully according not only to disease factors but also to the social background of patients. We aimed to clarify long-term outcomes after TP, including the living conditions and quality of life (QoL), of surviving patients.

METHODS

Medical records of 44 consecutive patients who underwent TP between 1990 and 2013 were reviewed retrospectively; 25 survivors completed cross-sectional clinical surveys and responded to a questionnaire about QoL using Short Form 36v2.

RESULTS

Prevalence of morbidity and mortality after TP was 32 and 5 %, respectively. Postoperative complications occurred more frequently in elderly patients than in young patients (48 vs. 14 %; P = 0.02); however, there was no significant difference in mortality, postoperative hospital stay, or survival. Twenty-four of 25 survivors (96 %) could manage pancreatogenic diabetes by themselves, and the median level of glycosylated hemoglobin was 7.4 %. Although one-third of patients after TP complained of diarrhea and the QoL scores of patients with diarrhea were lower than those of patients without diarrhea, QoL scores after TP were virtually comparable with those of the national population, even in elderly patients.

CONCLUSIONS

TP can be performed safely, even in elderly patients. QoL after TP seems to be acceptable if patients are capable of self-management.

Efficacy of repeated cytology of pancreatic juice obtained by endoscopic nasopancreatic drainage tube for early diagnosis of pancreatic cancer: a case series including a case of carcinoma in situ

Repeated cytology of pancreatic juice obtained by endoscopic nasopancreatic drainage (ENPD) tube has been highlighted as an early diagnostic method for small pancreatic cancer, including carcinoma in situ. We report two cases of early-stage pancreatic cancer diagnosed using repeated cytology; both cases underwent curative resection. No significant masses were found on conventional imaging in either case, with only pancreatic duct strictures being observed. ENPD tubes were placed to collect pancreatic juice in both cases. In case 1, two of five pancreatic juice samples showed adenocarcinoma. Therefore, distal pancreatectomy was performed, and a PanIN3 grade neoplasm (carcinoma in situ) was identified at the branch duct near the distal stricture. In case 2, two of seven pancreatic juice samples (collected during the second tube placement) showed adenocarcinoma. Therefore, distal pancreatectomy was performed, and a PanIN3 neoplasm was identified primarily in the pancreatic duct at a narrow section with fibrosis. Partial microinvasion (<1 mm) was observed at the branch duct. Repeated cytology of pancreatic juice obtained by ENPD tube is effective for early diagnosis of pancreatic cancer, especially in cases without mass formation. However, some issues, including the appropriate number of samples, should be addressed in large prospective studies.

Extent of Surgery and Implications of Transection Margin Status after Resection of IPMNs

Appropriate surgical strategies for management of intraductal papillary mucinous neoplasms (IPMNs) of the pancreas are a matter of debate. Preoperative and intraoperative evaluation of malignant potential of IPMN and of patient's comorbidities is of paramount importance to balance potential complications of surgery with tumors' risk of being or becoming malignant; the decision about the extent of pancreatic resection and the eventual total pancreatectomy needs to be determined on individual basis. The analysis of frozen-section margin of pancreas during operation is mandatory. The goal should be the complete resection of IPMN reaching negative margin, although there is still no agreed definition of “negative margin.” Of note, the presence of deepithelization is often wrongly interpreted as absence of neoplasia. Management of resection margin status and stratification of surveillance of the remnant pancreas, based on characteristics of primary tumour, are of crucial importance in the management of IPMNs in order to decrease the risk of tumor recurrence after resection. Although risk of local and distant recurrence for invasive IPMNs is increased even in case of total pancreatectomy, also local recurrence after complete resection of noninvasive IPMNs is not negligible. Therefore, a long-term/life-time follow-up monitoring is of paramount importance to detect eventual recurrences.

Treatment strategy for main duct intraductal papillary mucinous neoplasms of the pancreas based on the assessment of recurrence in the remnant pancreas after resection: a retrospective review

OBJECTIVES

To clarify the recurrence pattern after resection of main duct intraductal papillary mucinous neoplasms (MD-IPMNs) using molecular analyses and determine the most adequate treatment strategy.

BACKGROUND

The most appropriate resection line for MD-IPMNs remains an unresolved issue.

METHODS

Medical records of 56 patients with pancreatectomy were retrospectively reviewed. Histological subtypes and Kras/GNAS mutations were assessed in patients with recurrence in the remnant pancreas.

RESULTS

Forty-nine patients underwent partial pancreatectomy and 7 underwent total pancreatectomy. Thirty-six patients (64%) had malignant MD-IPMNs. Recurrence was observed in 7 of 49 patients (14%), including 6 with malignant IPMNs and 1 with pancreatic ductal adenocarcinoma, all of whom underwent remnant pancreatectomy. The cumulative disease-specific survival rate of patients with pancreatic recurrence was greater than that of patients with extrapancreatic recurrence (P < 0.001). Although the pancreatic margin status at the initial operation did not affect the pancreatic recurrence rate, all 4 recurrent IPMNs examined had histological subtypes and Kras/GNAS mutations identical to those of the initial lesions. Four patients experienced recurrence in the remnant pancreas or systemic recurrence after resection of high-grade dysplasia of MD-IPMN. Three of the 56 patients had concomitant pancreatic ductal adenocarcinomas and MD-IPMNs.

CONCLUSIONS

One-step total pancreatectomy can be avoided, and remnant total pancreatectomy would lead to favorable outcomes even in patients with pancreatic recurrence, some cases of which seem to involve residual lesions. Postoperative surveillance of high-grade dysplasia should be performed as if malignant, and close attention should be paid to the occurrence of concomitant pancreatic ductal adenocarcinomas in patients with MD-IPMNs.

Treatment of pancreatic cystic neoplasm: surgery or conservative?

Pancreatic cystic neoplasms (PCNs) are a heterogeneous group of tumors with distinct biological features. These neoplasms are now being recognized more frequently owing to advances in cross-sectional imaging and increasing awareness. Guidelines for treatment of the common and clinically important PCNs frequently have been revised in view of the continuing controversies and evolving clinical data. This review summarizes the management approaches of the common and clinically important PCNs based on current evidence and guidelines.

Intraoperative pancreatoscopy with narrow band imaging: a novel method for assessment of resection margins in case of intraductal papillary mucinous neoplasm

BACKGROUND

Intraductal papillary mucinous neoplasm (IPMN) is characterized by intraductal proliferation of neoplastic mucinous cells with a variable extent along the main duct or its branches. The lesion may be continuous or discontinuous. Skip lesions have been described in about 6-19% of cases. Complete resection without leaving behind any skip lesions is important, to such an extent that many groups suggest even total pancreatectomy, a major and morbid surgery.

METHODS

A 40 year-male patient with chronic pancreatitis presented with recent-onset diabetes mellitus and weight loss. Ultrasound and computed tomography (CT) scan showed a cystic lesion in the head and uncinate process of pancreas. Peroral pancreatoscopy showed villous projections with dilated tortuous vessel in the head, suspicious of IPMN. The duct beyond pancreatic head could not be visualized and remained unassessed. At pancreatoduodenectomy, pancreatoscopy with narrow band imaging (NBI) was done using flexible pancreatoscope through the cut end of the duct at the neck to assess the duct in the body and tail.

RESULTS

Pancreatoscopy with NBI showed a normal-looking resection margin and a skip lesion 1 cm beyond it. The revised resection margin confirmed the skip lesion on frozen section and also that the fresh cut margin was negative. The remaining duct in the body and tail was normal on pancreatoscopy. Total clearance of the disease could be achieved without a major procedure such as total pancreatectomy.

CONCLUSIONS

Intraoperative pancreatoscopy, especially with NBI, is a good diagnostic tool for IPMN and also helps in intraoperative decision-making of the resection margins.

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.

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 tumors of the pancreas: biology, diagnosis, and treatment

Pancreatic intraductal papillary mucinous neoplasms (IPMNs) rank among the most common cystic tumors of the pancreas. For a long time they were misdiagnosed as mucinous cystadenocarcinoma, ductal adenocarcinoma in situ, or chronic pancreatitis. Only in recent years have IPMNs been fully recognized as clinical and pathological entities, although their origin and molecular pathogenesis remain poorly understood. IPMNs are precursors of invasive carcinomas. When resected in a preinvasive state patient prognosis is excellent, and even when they are already invasive, patient prognosis is more favorable than with ductal adenocarcinomas. Subdivision into macroscopic and microscopic subtypes facilitates further patient risk stratification and directly impacts treatment. There are main duct and branch duct IPMNs, with the main duct type including the intestinal, pancreatobiliary, and oncocytic types and the branch duct type solely harboring the gastric type. Whereas main duct IPMNs have a high risk for malignant progression, demanding their resection, branch duct IPMNs have a much lower risk for harboring malignancy. Patients with small branch duct/gastric-type IPMNs (<2 cm) without symptoms or mural nodules can be managed by periodic surveillance.

Role of frozen section assessment for intraductal papillary and mucinous tumor of the pancreas

Intraductal papillary mucinous neoplasms (IPMN) of the pancreas include a spectrum of dysplasia ranging from minimal mucinous hyperplasia to invasive carcinoma and are extensive tumors that often spread along the ductal tree. Several studies have demonstrated that preoperative imaging is not accurate enough to adapt the extent of pancreatectomy and have suggested routinely using frozen sectioning (FS) to evaluate the completeness of resection and also to check if ductal dilatation is active or passive, in order to avoid an excessive pancreatic resection. Separate main duct and branch duct analysis is needed due to the difference in the natural history of the disease. FS accuracy averages 95%. Eroded epithelium on the main duct, severe ductal inflammation mimicking dysplasia and reactive epithelial changes secondary to obstruction can lead to inappropriate FS results. FS results change the planned extent of resection in up to 30% of cases. The optimal cut-off leading to extend pancreatectomy is not consensual and our standard option is to extend pancreatectomy if FS reveals: (1) at least IPMN adenoma on the main duct; or (2) at least borderline IPMN on branch ducts; or (3) invasive carcinoma. However, the decision to extend resection must be taken after a multidisciplinary discussion since it does not exclusively depend on the FS result but also on age, general condition and expected prognosis after resection. The main limitation of using FS is the existence of discontinuous (“skip”) lesions which account for approximately 10% of IPMN in surgical series and can lead to reoperation in up to 8% of cases.

Intraductal papillary mucinous neoplasm: a clinicopathologic review

Intraductal papillary mucinous neoplasm (IPMN) is an intraductal mucin-producing epithelial neoplasm that arises from the main pancreatic duct (MD-IPMN), secondary branch ducts (BD-IPMN), or both (mixed type; Mix-IPMN). Neoplastic progression from benign adenoma to invasive adenocarcinoma has not been proven but is generally thought to occur. With increasing recognition of IPMN, our understanding of the diagnosis and management of the tumors is evolving. At present, treatment options for patients with IPMN range from observation to pancreatic resection depending on the natural history of the lesion. This review focuses on currently available data that guide management decisions for patients with IPMN.

Intraductal papillary mucinous neoplasm of the pancreas (IPMN): clinico-pathological correlations and surgical indications

Background

Intraductal papillary mucinous neoplasms (IPMNs) are increasingly recognized entities, whose management remains sometimes controversial, due to the high rate of benign lesions and on the other side to the good survival after resection of malignant ones.

Methods

Retrospective analysis of a prospectively collected Western series of IPMN.

Results

Forty cases of IPMN were analysed (1992-2007). Most patients were symptomatic (72.5%); cholangio-MRI had the best diagnostic accuracy both for the tumour nature (83.3%) and for the presence of malignancy (57.1%). ERCP was done in 8 cases (20%), and the results were poor. Thirteen patients were treated by pancreatic resection and 27 were maintained in follow-up. Total pancreatectomy was performed in 46% of the cases; in situ and invasive carcinoma were recognized in 15.4% and 38.4% of the cases, respectively. The mean follow-up was 42 months (range 12-72). One only patients with nodal metastases died 16 months after the operation for disease progression, while 91.6% of the operated patients are disease free. Out of the 27 not resected patients, 2 out of 4 presenting a lesion at high risk for malignancy died, while the remaining are in good conditions and disease free, with a mean follow-up of 31 months.

Conclusion

Therapeutic indication for IPMNs is mainly based upon radiological evaluation of the risk of malignancy. While the main duct tumours should be resected, preserving whenever possible a portion of the gland, the secondary ducts tumours may be maintained under observation, in absence of radiological elements of suspicion such as size larger than 3 cm, or a wall greater than 3 mm or nodules or papillae in the context of the cyst.

[Limited pancreatic resections for intraductal papillary mucinous neoplasm]

INTRODUCTION

For non-invasive intraductal papillary and mucinous neoplasm (IPMN) with limited extent, pancreaticoduodenectomy (PD) or distal pancreatectomy (DP) seem excessive due to the risk of pancreatic insufficiency. Enucleation (EN) or medial pancreatectomy (MP) are not commonly performed for IPMN. The aim of this study was to evaluate the feasibility and results of EN and MP for non-invasive IPMN.

PATIENTS AND METHODS

Of 249 patients with IPMN, we attempted a limited resection in 50 (20%) EN (n=31) or MP (n=20) with routine intra-operative frozen section pathology. One attempted EN was converted to MP. Indications for surgery were pain/pancreatitis (44%), suspicion of main duct involvement (28%), mural nodules in branch duct (14%), branch duct>30 mm (8%) or suspicion of mucinous cystadenoma (6%). Follow-up clinical assessment and MRI were performed on a yearly basis.

RESULTS

Of the 31 attempted enucleations, 5 (13%) were immediately converted (4 PD, 1 MP) due to technical reasons (n=3) or due to findings on frozen section (n=2). At definitive pathological examination (accuracy of frozen sectioning=98%), branch ducts were involved by mild (n=21), moderate (n=7) or high grade dysplasia (n=2). One patient underwent a double EN. Of 20 attempted medial pancreatectomies, 8 (40%) required additional segmental resection due to significant IPMN lesions at pancreatic margins; 3 of the additional resection margins were tumor-free, and 5 were involved by IPMN (4 conversions to PD or DP, one contra-indication to PD). Overall, 49 pancreatic margins were analyzed by frozen sectioning with 98% accuracy. Resected specimens of 16 MP showed involvement by mild (n=7), moderate (n=7) or high grade dysplasia (n=2). There was no postoperative mortality. Median length of stay was 21 and 30 days respectively after EN and MP. Pancreatic fistula rate was 54% and 81% respectively after EN and MP. Three patients underwent early re-operation for hemorrhage. Overall median follow-up was 24 months (3-121). All patients are alive, 2 patients (5%) have presented with recurrent pain and 4 have developed tumor recurrence on imaging follow-up (4/33=12%). Two patients (5%) developed de novo diabetes (one after EN combined with DP) and a third patient developed worsening of pre-existing diabetes plus exocrine insufficiency. No patient had surgery for recurrence.

CONCLUSIONS

EN and MP are feasible for non-invasive IPMN. Their significant early morbidity is counterbalanced by low rates of both long-term functional disorders and tumor recurrence.

Intraductal papillary mucinous neoplasms of the pancreas: indication, extent, and results of surgery

In intraductal and papillary mucinous neoplasm (IPMN) of the pancreas, the aims of surgery differ according to the presence of malignancy. For malignant IPMN and especially for invasive malignancy, radical resection is essential, but entails a substantial operative risk and long-term pancreatic insufficiency. For benign IPMN, in theory, the operative risk and the loss of pancreatic function should be minimal. Thus, surgery for malignant and benign IPMN differs in patient selection, surgical technique, and accepted risk of long-term functional disorders. This article details the indications, surgical techniques, and results of surgery in IPMN.

Natural history of intraductal papillary mucinous neoplasms (IPMN): current evidence and implications for management

Intraductal papillary mucinous neoplasms (IPMNs) show varying degrees of dysplasia throughout the neoplasm that can range from adenoma to invasive carcinoma, with dysplastic changes of borderline neoplasms and carcinoma in situ in between. An understanding of the natural history, and especially the required time to transform into either carcinoma in situ or an invasive adenocarcinoma, is critically important for management policy. This topic serves as the rationale for the present analysis. At the beginning of February 2007, using the key word "IPMN" in PubMed, we initially selected 119 publications using the principal criteria as defined by the WHO classification. We identified 20 appropriate original reports and one consensus paper. Neither randomized control trials (RCT) or systematic reviews of RCTs (level 1 evidence) nor cohort studies or reviews of cohort studies (level 2 evidence) have been published. Only one report fit the criteria for level 3 evidence (case control study). Nineteen papers satisfied criteria for level 4 (cases series) and two for level 5 (expert opinion publication). After additional review and analysis, we considered only six reports to be "cornerstone papers" of merit for the final review. Clues to the natural history of IPMNs can be gained by using several methods to examine the articles: (a) to verify different prognoses between main and side branch duct subtypes; (b) to compare the average age of patients with benign vs. malignant IPMNs; (c) to summarize the findings of nonoperative, observational studies based on follow up by clinical, biochemical, and imaging techniques without operative resection; (d) to determine the prognostic importance of the status of the resection margin; and (e) to follow patients clinically after surgical resection. Although important aspects of the natural history of IPMN are still unknown, the following conclusions can be drawn: (1) Branch-duct IPMNs are less aggressive than main-duct IPMNs. (2) Malignancy is more common in older patients. (3) Malignancy (invasive or carcinoma in situ) is found in about 70% of resected main-duct IPMNs. (4) After resection of noninvasive IPMNs (branch- and main-duct varieties), recurrence is rare (<8%). (5) After resection of invasive IPMN, recurrence occurs in 50-65% of patients.

Intraductal papillary mucinous neoplasms of the pancreas

Intraductal papillary mucinous neoplasms (IPMNs) of the pancreas are now a well-recognized category of slowly growing tumors with a remarkably better prognosis, even when malignant, than pancreatic ductal adenocarcinoma. Their clinical and pathohistologic features have been increasingly attracting the attention of clinicians since their first description 25 years ago. Despite its burgeoning volume recently, accumulated literature devoted to IPMN still provides a low level of evidence with regard to diagnosis, treatment, and prognosis. Therefore, we performed a Medline-based systematic review of the literature aimed at clearly defining the clinicopathologic characteristics of pancreatic IPMN and determining the best currently available evidence-based principles of diagnosis and management of patients with this disease.