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

Assessment of Malignant Potential in Intraductal Papillary Mucinous Neoplasms of the Pancreas: Comparison between Multidetector CT and MR Imaging with MR Cholangiopancreatography

PURPOSE

To compare the diagnostic performance of multidetector computed tomography (CT) and magnetic resonance (MR) imaging with MR cholangiopancreatography (MRCP) in identifying the malignant potential of pancreatic intraductal papillary neoplasms (IPMNs) and evaluate their intermodality agreement.

MATERIALS AND METHODS

Institutional review board approval was obtained, and the requirement for informed consent was waived for this retrospective study. In 129 patients with pathologically proved pancreatic IPMNs, three reviewers independently evaluated their preoperative CT and MR imaging with MRCP findings. Intermodality agreement between multidetector CT and MR imaging with MRCP, as well as interobserver agreement of each imaging modality, for depicting high-risk stigmata and worrisome features were assessed. Diagnostic values of other signs of overt malignancy, including the presence of a parenchymal mass and local-regional extension, were analyzed. Diagnostic performance and intermodality agreement were assessed by using receiver operating characteristics (ROC) curve analysis and weighted κ statistics.

RESULTS

Overall, multidetector CT and MR imaging with MRCP were similar in their ability to depict signs suspicious or indicative of malignancy in patients with IPMN (area under the ROC curve [AUC] = 0.82 for both), with good intermodality agreement (κ = 0.75) and moderate interobserver agreement (κ = 0.47-0.59) when high-grade dysplasia was used as the cutoff for malignancy. When parenchymal masses and local-regional extensions were also considered as overt signs of malignancy, the ability to identify invasive IPMNs significantly increased (AUC = 0.87 for CT and AUC = 0.88 for MR imaging), with high sensitivity (94.3%), while maintaining specificity (69.1%).

CONCLUSION

The diagnostic performance of multidetector CT and MR imaging with MRCP for identifying the malignant potential of pancreatic IPMNs was similar and showed good intermodality agreement, suggesting that follow-up with either modality may be used.

Malignant transformation and overall survival of morphological subtypes of intraductal papillary mucinous neoplasms of the pancreas: A network meta-analysis

BACKGROUND

Emerging evidence suggests the predictive role of morphological subtypes (gastric, intestinal, pancreatobiliary, and oncocytic) of intraductal papillary mucinous neoplasms (IPMNs) in malignant transformation and overall survival. But results of these studies are currently discordant.

METHODS

A comprehensive literature search in MEDLINE, EMBASE, and Cochrane Central Register of Controlled Trials (CENTRAL) was conducted for eligible studies. Network meta-analysis using the random-effect model was carried out to detect differences in incidences of invasive IPMNs and hazard ratios from survival curves among four morphological subtypes.

RESULTS

19 studies were included in the network comparison. The outcomes showed that pancreatobiliary-type (OR for odds ratio=25.87, 95% CI: 12.11-52.10, compared with gastric-type) and oncocytic-type (OR=18.59, 95% CI: 7.18-42.74) IPMNs had the highest risks of progressing to invasive IPMNs, followed by intestinal-type (OR=5.71, 95% CI: 2.85-10.61) and gastric-type IPMNs. With the gastric type as the baseline, pancreatobiliary-type IPMNs were found to have the worst prognosis (HR for hazard ratio=5.05, 95% CrI: 1.33-13.47) while no significant differences were found for the intestinal type (HR=1.90, 95% CrI: 0.59-4.58) and the oncocytic type (HR=3.29, 95% CrI: 0.75-9.71).

CONCLUSION

It is suggested that pancreatobiliary-type IPMNs are the most likely to become invasive and are associated with poor prognosis. In contrast, the other three subtypes have similar overall survivals even though the oncocytic- and intestinal-type IPMNs are predisposed to be more invasive than gastric-type IPMNs.

Thirty years of experience with intraductal papillary mucinous neoplasm of the pancreas: from discovery to international consensus

BACKGROUND

Intraductal papillary mucinous neoplasm (IPMN) of the pancreas is characterized by intraductal papillary proliferation of mucin-producing epithelial cells that exhibit various degrees of dysplasia. IPMN is classified as the main duct type (MD-IPMN) and the branch duct type (BD-IPMN) according to the location of involvement, and into four histological subtypes (gastric, intestinal, pancreatobiliary, and oncocytic) according to the histomorphological and immunohistochemical characteristics. Mucin core protein expression correlates with the biological behavior and prognosis of the tumor. DNA analysis has shown that IPMN is associated with a number of gene mutations, but the roles of many of these mutations require further investigation. Most patients with MD-IPMN undergo tumor resection. Patients with BD-IPMN who do not undergo resection may develop malignant change, and concomitant separate pancreatic cancer occurs in 2-10% of patients with IPMN. Patients with a strong family history may develop multiple BD-IPMNs as well as concomitant pancreatic cancer. Malignant changes are relatively easy to detect, especially by endoscopic ultrasonography (EUS), but the optimal surveillance protocol is currently unclear.

KEY MESSAGES

The 2012 guidelines for the management of IPMN recommend that patients with 'high-risk stigmata' (obstructive jaundice, enhanced solid component, and main pancreatic duct size ≥10 mm) should undergo resection. Patients with 'worrisome features' (cyst size ≥3 cm, thickened enhanced cyst walls, non-enhanced mural nodules, main pancreatic duct size 5-9 mm, abrupt change in main pancreatic duct caliber with distal pancreatic atrophy, lymphadenopathy, and clinical acute pancreatitis) should be evaluated by EUS. EUS is a more sensitive test than computed tomography or magnetic resonance imaging for the early detection of malignancy.

CONCLUSIONS

Most patients with MD-IPMN should undergo tumor resection. Patients with BD-IPMN who do not undergo resection should undergo careful surveillance including EUS for the early detection of malignant change and separate pancreatic cancer.

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.

Branch duct intraductal papillary mucinous neoplasm of the pancreas: single-center experience with 324 patients who underwent surgical resection

Backgrounds/Aims

International treatment guidelines for branch duct intraductal papillary mucinous neoplasm (BD-IPMN) of the pancreas have been proposed, for features associated with malignancy and invasiveness. We investigated the clinicopathological characteristics that are predictive of malignancy or invasiveness and disease recurrence.

Methods

A review of 324 patients with resected and pathologically confirmed BD-IPMN, between March 1997 and December 2013, was conducted.

Results

There were 144 (44.4%) low grade dysplasia (LGD), 138 (42.6%) intermediate grade dysplasia (IMGD), 17 (5.3%) high grade dysplasia (HGD), and 25 (7.7%) invasive carcinoma (invIPMC) cases. The 5-year survival rates were 98.1% for LGD, 95.3% for IMGD, 100% for HGD, and 71.8% for invIPMC. Through a univariate analysis, the male sex was associated with malignancy, and CA19-9 was related to both malignant and invasive IPMN. The high risk or worrisome features of the international guidelines were associated with both malignant and invasive IPMN: the total bilirubin of the head/uncinate lesion, tumor size, mural nodule, and the size of the main pancreatic duct (MPD). Through a multivariate analysis, the male sex, elevated CA19-9, mural nodule, and dilated MPD diameter were independently correlated with the malignant IPMN. The elevated CA19-9 and dilated MPD diameter were also correlated with invasive carcinoma. The patient age and the initial pathological diagnosis were strongly associated with disease recurrence following surgical resection.

Conclusions

The high risk or worrisome features in the current treatment guidelines for BD-IPMN are confined to the morphological characteristics of the disease. Patient factors and biological features should also be considered in order to develop optimal therapeutic or surveillance strategies.

Main- and Branch-Duct Intraductal Papillary Mucinous Neoplasms: Extent of Surgical Resection

Background

Surgical treatment of intraductal papillary mucinous neoplasms (IPMN) requires a differentiated approach regarding indications and extent of resection.

Methods

The review summarizes the current literature on indication, timing, and surgical procedures in IPMN.

Results

The most important differentiation has to be made between main-duct and branch-duct IPMN as well as mixed-type lesions that biologically mimic main-duct types. In main-duct and mixed-type IPMN, the resection should be indicated by the time of the diagnosis – in accordance with the international consensus guidelines – and should follow oncological principles. Depending on IPMN localization, this implies partial pancreatoduodenectomy, distal pancreatectomy, or total pancreatectomy and includes the corresponding types of lymphadenectomy. Furthermore, branch-duct IPMN > 3 cm or bearing high-risk features (mural nodules in magnetic resonance imaging, computed tomography, or endoscopic ultrasound imaging; symptomatic lesions; elevated tumor markers) are similarly treated. As the risk for malignancy in smaller branch-duct IPMN is lower, the decision for surgical treatment is often individually made – despite the updated 2012 guidelines. In these lesions, limited surgical approaches, including enucleation and central pancreatectomy, are possible.

Conclusion

Timely and radical resection of IPMN offers the unique opportunity to prevent pancreatic cancer, and even in malignant IPMN surgery can offer a curative approach with excellent long-term outcome in early stages. A structured imaging follow-up should be considered to recognize IPMN recurrence and metachronous pancreatic cancer as well as gastrointestinal neoplasias by endoscopic surveillance.

IPMN involving the main pancreatic duct: biology, epidemiology, and long-term outcomes following resection

OBJECTIVES

To describe the characteristics of intraductal papillary mucinous neoplasms (IPMNs) with predominant involvement of the main pancreatic duct (MPD), analyzing predictors for survival and recurrence.

BACKGROUND

IPMNs involving the MPD harbor a high likelihood of malignancy and different biological features. The appropriateness of including cases with minimal noncircumferential MPD involvement has been challenged because these show clinicopathological features that are similar to branch duct IPMN. Accordingly, their exclusion has led to a redefinition of MPD IPMN (MD-IPMN).

METHODS

Retrospective review of resected MD-IPMN from 1990 to 2013. All slides were reviewed by a single pancreatic pathologist and classified on the basis of epithelial type and invasive component.

RESULTS

A total of 223 patients underwent resection for IPMN involving the MPD. Of these, 50 were excluded because of minimal MPD involvement. Among the 173 patients analyzed, median age was 68 years and 55% were males. Predominant epithelial phenotype was intestinal (50%). Forty-eight patients (28%) had low- or intermediate-grade dysplasia, whereas 125 (72%) had either high-grade dysplasia (33%) or invasive carcinoma (39%). Of the 67 invasive IPMNs, 39 were tubular carcinomas (58%) and invasion was minimal (<5 mm) in 28 (42%). The 5-year overall survival rate was 69% and the disease-specific survival rate was 83%. The estimated recurrence rate at 10 years was 25%. Size and type of the invasive component, lymph node positivity, and a positive resection margin were predictors for both survival and recurrence (P < 0.05).

CONCLUSIONS

MD-IPMN is mainly intestinal-type and malignant. After resection, it has a very favorable prognosis, especially in the absence of macroscopic invasive carcinoma.

Navigation surgery using an augmented reality for pancreatectomy

AIM

The aim of this study was to evaluate the utility of navigation surgery using augmented reality technology (AR-based NS) for pancreatectomy.

METHODS

The 3D reconstructed images from CT were created by segmentation. The initial registration was performed by using the optical location sensor. The reconstructed images were superimposed onto the real organs in the monitor display. Of the 19 patients who had undergone hepatobiliary and pancreatic surgery using AR-based NS, the accuracy, visualization ability, and utility of our system were assessed in five cases with pancreatectomy.

RESULTS

The position of each organ in the surface-rendering image corresponded almost to that of the actual organ. Reference to the display image allowed for safe dissection while preserving the adjacent vessels or organs. The locations of the lesions and resection line on the targeted organ were overlaid on the operating field. The initial mean registration error was improved to approximately 5 mm by our refinements. However, several problems such as registration accuracy, portability and cost still remain.

CONCLUSION

AR-based NS contributed to accurate and effective surgical resection in pancreatectomy. The pancreas appears to be a suitable organ for further investigations. This technology is promising to improve surgical quality, training, and education.

Clinical significance of GNAS mutation in intraductal papillary mucinous neoplasm of the pancreas with concomitant pancreatic ductal adenocarcinoma

OBJECTIVE

The aims of this study were to investigate the GNAS mutational status in pancreatic intraductal papillary mucinous neoplasm (IPMN) with and without distinct pancreatic ductal adenocarcinoma (PDAC) and to evaluate the significance of GNAS analysis using duodenal fluid (DF) in patients with IPMN.

METHODS

The clinicopathologic features of 110 patients with IPMN including 16 with distinct PDAC were reviewed. The GNAS status in the IPMN tissue and 23 DF specimens was assessed by sensitive mutation scanning methods.

RESULTS

The GNAS mutation rate in IPMN with distinct PDAC was significantly lower than that in IPMN without PDAC (4/16, 25%, vs 61/94, 65%; P = 0.0047). By multivariate analysis, GNAS wild-type and gastric type IPMNs were significantly associated with distinct PDAC. Of 45 GNAS wild-type IPMNs, 10 (43%) of 23 gastric type IPMNs had distinct PDAC, whereas only 2 (9%) of 22 non-gastric type IPMNs had distinct PDAC (P = 0.017). The GNAS status in DF was consistent with that in tissue in 21 (91%) of 23 patients.

CONCLUSIONS

Distinct PDACs frequently develop in the pancreas with gastric type IPMN without GNAS mutations. Duodenal fluid DNA test would predict the GNAS status of IPMN, whereas the detection of the gastric subtype using noninvasive test remains to be determined.

"High-risk stigmata" of the 2012 international consensus guidelines correlate with the malignant grade of branch duct intraductal papillary mucinous neoplasms of the pancreas

OBJECTIVES

The 2012 international consensus guidelines for the management of intraductal papillary mucinous neoplasm (IPMN) of the pancreas stratified patients into 2 clinical categories, "high-risk stigmata" and "worrisome features," and recommended different therapeutic strategies for these groups. The aim of this study was to elucidate the significance of these categories in terms of predicting malignant IPMNs.

METHODS

The medical records of 100 consecutive patients who underwent pancreatectomy for IPMNs were retrospectively reviewed. Seventy patients with branch duct IPMNs (BD-IPMNs) were stratified into 3 groups. The relationships between the number of predictive factors and histopathologic grade were investigated.

RESULTS

The prevalence rates of malignant IPMN, invasive carcinoma, and lymph node metastasis in the high-risk group were 80%, 55%, and 20%, respectively, with these percentages significantly increasing in a stepwise manner according to the number of predictive factors. In contrast, there was no significant correlation between the number of worrisome features and grade of malignancy in patients stratified as having worrisome BD-IPMNs.

CONCLUSIONS

The number of high-risk stigmata correlated significantly with the grade of malignancy of BD-IPMNs. The presence of at least 1 high-risk stigma in patients with BD-IPMNs indicates a need for pancreatectomy with lymphadenectomy.

An increased total resected lymph node count benefits survival following pancreas invasive intraductal papillary mucinous neoplasms resection: an analysis using the surveillance, epidemiology, and end result registry database

Background

The therapeutic effect of lymph node dissection for pancreas invasive intraductal papillary mucinous neoplasms (IPMN) remains unclear. The study investigated whether cancer-specific survival (CSS) and overall survival (OS) rates among invasive IPMN patients improve when more lymph nodes are harvested during surgery.

Study Design

The study cohort was retrieved from the Surveillance, Epidemiology, and End Results (SEER) database. The lymph node count was categorized into quartiles. The relationship between lymph node count and survival was analyzed using Kaplan–Meier curves and a Cox proportional-hazards model. The stage migration was assessed by Chi-square tests. Propensity score matching (PSM) was used to minimize confounding variables between groups.

Results

In total, 1,080 patients with resected invasive IPMNs from 1992 to 2011 were included. Univariate and multivariate Cox models indicated that an increased lymph node count independently improves survival. The Kaplan-Meier and log-rank tests identified 16 nodes as an optimal cut-off value that yielded a significant survival benefit for all invasive IPMN patients. The stage migration effect existed in this cohort. After PSM, the 5-year CSS increased from 36% to 47%, and the median survival rate increased from 30 months to 40 months by increasing the lymph node count to over 16, alone. The 5-year OS rate also provided additional support for this result.

Conclusion

Increased lymph node counts were associated with improved survival in invasive IPMN patients. One cut-off value of lymph node count was 16 for this improvement.