Intraductal papillary mucinous neoplasms of the pancreas--a surgical disease

Photon-counting CT: technical features and clinical impact on abdominal imaging

Photon-counting CT has a completely different detector mechanism than conventional energy-integrating CT. In the photon-counting detector, X-rays are directly converted into electrons and received as electrical signals. Photon-counting CT provides virtual monochromatic images with a high contrast-to-noise ratio for abdominal CT imaging and may improve the ability to visualize small or low-contrast lesions. In addition, photon-counting CT may offer the possibility of reducing radiation dose. This review provides an overview of the actual clinical operation of photon-counting CT and its diagnostic utility in abdominal imaging. We also describe the clinical implications of photon-counting CT including imaging of hepatocellular carcinoma, liver metastases, hepatic steatosis, pancreatic cancer, intraductal mucinous neoplasm of the pancreas, and thrombus.

Utility of Radiological Follow Up of Main-Duct Intraductal Papillary Mucinous Neoplasms and Mixed-Type Intraductal Papillary Mucinous Neoplasms

BACKGROUND

Intraductal papillary mucinous neoplasms (IPMNs) have the potential to evolve into pancreatic adenocarcinoma (PDAC). While main-duct IPMNs (MD-IPMNs), involving the main pancreatic duct (MPD), are less common than side-branch IPMNs (SB-IPMNs) or mixed-type IPMNs (mixed-IPMNs), their malignant transformation potential is far greater. Controversy exists between different guidelines in terms of recommended management strategies. This study was aimed at assessing the utility of the radiological follow up of MD-IPMNs and mixed-type IPMNs, including prevalence of worrisome radiological findings as well as clinical and laboratory parameters, and their correlation with the development of progression or pancreatic adenocarcinoma.

METHODS

Eighty-four patients with MD-IPMNs or mixed-type IPMNs who underwent at least one magnetic resonance cholangiopancreatography (MRCP) were included. Clinical and laboratory data were obtained retrospectively. A cross-sectional analysis was carried out to establish clinical and laboratory parameters associated with development of PDAC. A retrospective cohort analysis was performed on 44 patients who had at least six months of follow up, trying to identify factors correlating with worrisome radiological features.

RESULTS

Nine cases (10.7%) of PDAC were recorded in this cohort. The laboratory and imaging factors associated with cyst size progression greater than 5 mm during follow up were elevated alanine transaminase (ALT) levels, the maximal cyst size, and the MPD diameter. Cross-sectional analysis indicated that PDAC was associated with nausea (p = 0.01), as well as increased levels of aspartate aminotransferase (AST) (p = 0.05), gamma glutamyl transpeptidase (GGT) (p = 0.01), and alkaline phosphatase (ALP) (p = 0.01).

CONCLUSIONS

Elevated levels of liver enzymes were associated with IPMN progression and, subsequently, the development of PDAC. ALT levels, maximal cyst size, and MPD diameter are associated with the progression of cyst size. These data may aid in risk-stratifying patients when determining the follow up approach for IPMNs.

Contemporary report of surgical outcomes after single-stage total pancreatectomy: A 10-year experience

BACKGROUND

Surgeons rarely perform elective total pancreatectomy (TP). Our study seeks to report surgical outcomes in a contemporary series of single-stage (SS) TP patients.

METHODS

Between the years 2013 to 2023 we conducted a retrospective review of 60 consecutive patients who underwent SSTP. Demographics, pathology, treatment-related variables, and survival were recorded and analyzed.

RESULTS

SSTP consisted of 3% (60/1859) of elective pancreas resections conducted. Patient median age was 68 years. Ninety percent of these patients (n = 54) underwent SSTP for pancreatic ductal adenocarcinoma (PDAC). Conversion from a planned partial pancreatectomy to TP occurred intraoperatively in 31 (52%) patients. Fifty-nine patients (98%) underwent an R0 resection. Median length of hospital stay was 6 days. The majority of morbidities were minor, with 27% patients (n = 16) developing severe complications (Clavien-Dindo ≥3). Thirty and ninety-day mortality rates were 1.67% (one patient) and 5% (three patients), respectively. Median survival for the entire cohort was 24.4 months; 22.7 months for PDAC patients, with 1-, 3-, and 5-year survival of 68%, 43%, and 16%, respectively. No mortality occurred in non-PDAC patients (n = 6).

CONCLUSION

Elective single-stage total pancreatectomy can be a safe and appropriate treatment option. SSTP should be in the armamentarium of surgeons performing pancreatic resection.

SDC1 and ITGA2 as novel prognostic biomarkers for PDAC related to IPMN

The existing biomarkers are insufficient for predicting the prognosis of pancreatic ductal adenocarcinoma (PDAC). Intraductal papillary mucinous neoplasm (IPMN) is a precursor to PDAC; therefore, identifying biomarkers from differentially expressed genes (DEGs) of PDAC and IPMN is a new and reliable strategy for predicting the prognosis of PDAC. In this study, four datasets were downloaded from the Gene Expression Omnibus database and standardized using the R package 'limma.' A total of 51 IPMN and 81 PDAC samples were analyzed, and 341 DEGs in PDAC and IPMN were identified; DEGs were involved in the extracellular matrix and tumor microenvironment. An acceptable survival prognosis was demonstrated by SDC1 and ITGA2, which were highly expressed during in vitro PDAC cell proliferation, apoptosis, and migration. SDC1high was enriched in interferon alpha (IFN-α) response and ITGA2high was primarily detected in epithelial-mesenchymal transition (EMT), which was verified using western blotting. We concluded that SDC1 and ITGA2 are potential prognostic biomarkers for PDAC associated with IPMN. Downregulation of SDC1 and ITGA2 expression in PDAC occurs via a mechanism involving possible regulation of IFN-α response, EMT, and immunity, which may act as new targets for PDAC therapy.

New Diagnostic Modality Combining Mass Spectrometry and Machine Learning for the Discrimination of Malignant Intraductal Papillary Mucinous Neoplasms

BACKGROUND

An intraductal papillary mucinous neoplasm (IPMN) is a pancreatic tumor with malignant potential. Although we anticipate a sensitive method to diagnose the malignant conversion of IPMN, an effective strategy has not yet been established. The combination of probe electrospray ionization-mass spectrometry (PESI-MS) and machine learning provides a promising solution for this purpose.

METHODS

We prospectively analyzed 42 serum samples obtained from IPMN patients who underwent pancreatic resection between 2020 and 2021. Based on the postoperative pathological diagnosis, patients were classified into two groups: IPMN-low grade dysplasia (n = 17) and advanced-IPMN (n = 25). Serum samples were analyzed by PESI-MS, and the obtained mass spectral data were converted into continuous variables. These variables were used to discriminate advanced-IPMN from IPMN-low grade dysplasia by partial least square regression or support vector machine analysis. The areas under receiver operating characteristics curves were obtained to visualize the difference between the two groups.

RESULTS

Partial least square regression successfully discriminated the two disease classes. From another standpoint, we selected 130 parameters from the entire dataset by PESI-MS, which were fed into the support vector machine. The diagnostic accuracy was 88.1%, and the area under the receiver operating characteristics curve was 0.924 by this method. Approximately 10 min were required to perform each method.

CONCLUSION

PESI-MS combined with machine learning is an easy-to-use tool with the advantage of rapid on-site analysis. Here, we show the great potential of our system to diagnose the malignant conversion of IPMN, which would be a promising diagnostic tool in clinical settings.

Carbohydrate antigen 125 supplements carbohydrate antigen 19-9 for the prediction of invasive intraductal papillary mucinous neoplasms of the pancreas

BACKGROUND

Intraductal papillary mucinous neoplasms (IPMNs) are characterized by their abundant mucin production and malignant potential. IPMNs of the pancreas are mainly managed according to their radiographic indications, but this approach lacks accuracy with regard to IPMN grading. Therefore, serological biomarkers such as CA19-9 and CA125 (MUC16) should be employed to assist in predicting the invasiveness of IPMNs.

METHODS

We investigated the preoperative serum levels of CA19-9, CA125 and CEA in 381 surgical patients with a definite pathological diagnosis of IPMN from July 2010 to December 2019 at the Shanghai Cancer Center. We calculated the Youden indices of each point on the receiver operating characteristic (ROC) curves to identify the most appropriate cut-off values of CA19-9, CA125 and CEA for recognizing malignant IPMNs. Serological biomarker differences were correlated with clinicopathological features of IPMNs, and diagnostic indices of different scenarios were calculated to find the optimum strategy.

RESULTS

The malignant group had higher serum levels of CA19-9, CA125 and CEA. According to the ROC curves, the cut-off values of CA19-9, CA125 and CEA were readjusted to 38.3 U/ml, 13.4 U/ml and 5.3 μg/L. CA19-9 elevation was significantly associated with vascular invasion and perineural infiltration. CA125 showed good efficacy in predicting invasive IPMN in the CA19-9-negative subgroup.

CONCLUSIONS

Serological biomarkers are useful and sensitive indicators for recognizing invasive IPMNs. CA19-9 is the most important diagnostic index among all routinely measured serum biomarkers for differentiating malignant from benign IPMNs. CA19-9 should be combined with CA125 to enable more accurate predictions of IPMN malignancy.

Clinical Implication of Preoperative C-Reactive Protein/Albumin Ratio in Malignant Transformation of Intraductal Papillary Mucinous Neoplasm: A Propensity Score Analysis

Background: Inflammation-based scoring has been reported to be useful for predicting the recurrence and prognosis of various carcinomas. This study retrospectively investigated the relationship between inflammation-based score and intraductal papillary mucinous neoplasms (IPMNs). Methods: Between January 2013 and October 2018, we enrolled 417 consecutive patients with pancreatic tumors who received surgical resections at our hospital. The main outcome was the association between the preoperative inflammation-based score and their accuracy in predicting malignant transformation of IPMN. Results: Seventy six patients were eligible. Pathological findings indicated that 35 patients had low-grade dysplasia, 18 had high-grade dysplasia, and 23 had invasive carcinomas. As the C-reactive protein albumin ratio (CAR) was higher, malignant transformation of IPMNs also increased (p = 0.007). In comparing CAR^high and CAR^low using cutoff value, the results using a propensity score analysis showed that the CAR^high group predicted malignant transformation of IPMNs (odds ratio, 4.18; 95% confidence interval, 1.37–12.8; p = 0.01). In the CAR^high group, disease-free survival (DFS) was significantly shorter (p = 0.04). In the worrisome features, the AUC for the accuracy of malignant transformation with CAR^high was 0.84 when combining with the MPD findings. Conclusions: Preoperative CAR could be a predictive marker of malignant transformation of IPMNs.

Prognostic Analysis of Different Metastatic Patterns in Invasive Intraductal Papillary Mucinous Neoplasm: A Surveillance, Epidemiology, and End Results Database Analysis

OBJECTIVE

To evaluate the impacts of different metastatic patterns on the prognosis of patients with invasive intraductal papillary mucinous neoplasm (IPMN).

MATERIALS AND METHODS

All patients who were diagnosed with invasive IPMN in the Surveillance, Epidemiology, and End Results SEER database (2010-2015) were included in this study. They were grouped according to different metastatic patterns. Kaplan-Meier analysis and log-rank test were used for the comparison of their survival rates. The hazard ratio (HR) with 95% confidence interval (CI) was analyzed using the Cox proportional-hazards model.

RESULTS

A total of 2264 cases were included in this study. The most common metastatic site was the liver. The patients with the nonorgan metastasis demonstrated the best survival outcomes, while those with multiple metastases showed the worst survival outcomes. As compared to the patients with isolated liver metastasis, those with isolated lung and other organ metastases showed better overall survival rates and tumor-specific survival rates. The patients with liver, lung, multiple, and other organ metastases or of age >60 years were the independent predictors of poor prognosis.

CONCLUSIONS

The patients with isolated lung and other organ metastases demonstrated better survival outcomes as compared to those with isolated liver metastasis. The patients with nonorgan metastasis demonstrated the best survival outcomes, while those with multiple metastases showed the worst survival outcomes. Further studies are needed to determine a highly selected subset of patients, who might benefit from surgery or chemotherapy.

Management of pancreatic cysts and guidelines: what the gastroenterologist needs to know

The prevalence of pancreatic cysts has increased significantly over the last decade, partly secondary to increased quality and frequency of cross-sectional imaging. While the majority never progress to cancer, a small number will and need to be followed. The management of pancreatic cysts can be both confusing and intimidating due to the multiple guidelines with varying recommendations. Despite the differences in the specifics of the guidelines, they all agree on several high-risk features that should get the attention of any clinician when assessing a pancreatic cyst: presence of a mural nodule or solid component, dilation of the main pancreatic duct (or presence of main duct intraductal papillary mucinous neoplasm), pancreatic cyst size ⩾3–4 cm, or positive cytology on pancreatic cyst fluid aspiration. Other important criteria to consider include rapid cyst growth (⩾5 mm/year), elevated serum carbohydrate antigen 19-9 levels, new-onset diabetes mellitus, or acute pancreatitis thought to be related to the cystic lesion.

Assessment of Malignancy Potential in Intraductal Papillary Mucinous Neoplasms of the Pancreas on MDCT

RATIONALE AND OBJECTIVE

To assess the malignancy potential of intraduct papillary mucinous neoplasms (IPMNs) on multidetector-row computerized tomography according to the 2012 International Consensus Guidelines (ICG).

MATERIALS AND METHODS

This study retrospectively collected IPMNs confirmed by surgery from 2016 to 2019. The imaging findings of IPMNs were analyzed. IPMNs were classified as malignancy in the presence of high-grade dysplasia or invasive carcinoma and began in the presence of low- and intermediate-grade dysplasia.

RESULTS

A total of 207 patients (mean age: 63.7 ± 7.9 years) were included, and the prevalence of malignancy was 28.0% (58 of 207). According to the 2012 ICG, the imaging findings of IPMNs were divided into worrisome features (WFs) and high-risk stigmata (HRS). The malignancy of IPMN with only one WF was relatively low (1.4%, 3 of 207). In multivariate regression analyses, the independent factors of IPMNs were enhanced mural nodule ≥5 mm (odds ratio [OR] = 19.5, 95% confidence interval [CI] 6.8-55.4), abrupt change in the main pancreatic duct caliber with distal pancreatic atrophy (OR = 4.6, 95%CI 1.67-12.71), and thickened enhanced cyst walls (OR = 2.9, 95%CI 1.1-8.2). When the presence of more than two WFs or HRS (score ≥ 3) was regarded as indicating the malignancy potential of IPMNs on multidetector-row computerized tomography, the sensitivity, specificity, accuracy, positive predictive value (PPV) and negative predictive value (NPV) were 89.7%, 75.8%, 79.7%, 59.1%, and 95.0%, respectively.

CONCLUSION

According to the ICG in 2012, patients with IPMNs with only one WF have a low risk for malignancy, and the presence of at least two WFs or any HRS (score ≥3) suggests malignant IPMNs.

[Indications for the Surgical Management of Pancreatic Cystic Lesions]

A steady improvement in modern imaging as well as increasing age in society have led to an increasing number of cystic pancreatic tumours being detected. Pancreatic cysts are a clinically challenging entity because they span a broad biological spectrum and their differentiation is often difficult, especially in small tumours. Therefore, they require a differentiated indication for indication of surgery. To determine recommendations for the surgical indication in cystic tumours of the pancreas, a quality committee for pancreatic diseases of the German Society for General and Visceral Surgery performed a systematic literature search and created this review. Based on the current evidence, signs of malignancy and high-risk criteria (icterus due to cystic pancreatic duct obstruction in the bile duct, enhancing mural nodules ≥ 5 mm or solid components in the cyst or pancreatic duct ≥ 10 mm), as well as symptoms, are a surgical indication, independently of the cyst entity (except pseudocysts). If the entity of the pancreatic cyst is detectable by diagnostic imaging, all main duct IPMN and IPMN of the mixed type, all MCN > 4 cm and all SPN should be resected. SCN and branch-duct IPMN without worrisome features do not constitute an indication for surgery. The indication of operation in branch-duct IPMN with relative risk criteria and MCN < 4 cm is the subject of current discussions and should be individualised. By defining indication recommendations, the present work aims to improve the indication quality in cystic pancreatic tumours. However, the surgical indication should always be individualised, taking into account age, comorbidities and the patient's wishes.

Validation and head-to-head comparison of four models for predicting malignancy of intraductal papillary mucinous neoplasm of the pancreas: A study based on endoscopic ultrasound findings

BACKGROUND

Several models are currently available for predicting the malignancy of pancreatic intraductal papillary mucinous neoplasm (IPMN), namely, the Pancreatic Surgery Consortium (PSC), the Japan Pancreas Society (JPS), the Johns Hopkins Hospital (JHH), and the Japan-Korea (JPN-KOR) models. However, a head-to-head comparison that shows which model is more accurate for this individualized prediction is lacking.

AIM

To perform a head-to-head comparison of the four models for predicting the malignancy of pancreatic IPMN.

METHODS

A total of 181 patients with IPMN who had undergone surgical resection were identified from a prospectively maintained database. The characteristics of IPMN in patients were recorded from endoscopic ultrasound imaging data and report archives. The performance of all four models was examined using Harrell’s concordance index (C-index), calibration plots, decision curve analyses, and diagnostic tests.

RESULTS

Of the 181 included patients, 94 were categorized as having benign disease, and the remaining 87 were categorized as having malignant disease. The C-indexes were 0.842 [95% confidence interval (CI): 0.782-0.901], 0.704 (95%CI: 0.626-0.782), 0.754 (95%CI: 0.684-0.824), and 0.650 (95%CI: 0.483-0.817) for the PSC, JPS, JHH, and JPN-KOR models, respectively. Calibration plots showed that the PSC model had the least pronounced departure from ideal predictions. Of the remaining three models, the JPS and JHH models underestimated the probability of malignancy, while the JPN-KOR model overestimated the malignant potential of branch duct-IPMN. Decision curve analysis revealed that the PSC model resulted in a better clinical net benefit than the three other models. Diagnostic tests also showed a higher accuracy (0.801) for the PSC model.

CONCLUSION

The PSC model exhibited the best performance characteristics. Therefore, the PSC model should be considered the best tool for the individualized prediction of malignancy in patients with pancreatic IPMN.

[The mistakes in diagnosis of pancreatic intraductal papillary mucinous tumor]

It is presented surgical treatment of the patient with pancreatic intraductal papillary mucinous tumor who was under observation with diagnosis of chronic pancreatitis for a long time. Recurrent tumor with possible malignant transformation to carcinoma was suspected in 5 years after pancreaticoduodenectomy. It was supposed to perform pancreatic stump extirpation. Redo surgery did not reveal any tumor. The cause of recurrent pain was pancreatic duct obliteration at the level of anastomosis.

Clinical Management and Surgical Decision-Making of IPMN of the Pancreas

Intraductal papillary mucinous neoplasm (IPMN) is the most common pancreatic cystic neoplasm (PCN). The increased attention to IPMN is due to its unique features of malignant progression, being different between main duct IPMN and branch duct IPMN, and increased de novo development of conventional pancreatic ductal adenocarcinoma elsewhere in the pancreas. The increased interest in IPMN led to publication of many guidelines on its clinical management. This chapter aims to summarize and compare characteristics of nine guidelines on the clinical management of IPMN and other PCNs published in the English literature and further to show a current strategy for surgical decision making in the management of IPMN.

[Intraductal papillary mucinous neoplasm of pancreas]

Intraductal papillary mucinous neoplasm (IPMN) is the most common cystic pancreatic tumor. There are 3 ductal types of this tumor depending on localization. Several histological subtypes determine clinical course and prognosis. The problems of diagnosis, surgical treatment and follow-up are reviewed in several guidelines. Literature review devoted to pancreatic IPMN is presented in the article, the latest guidelines are compared.

Surgery of Cystic Tumors of the Pancreas - Why, When, and How?

The management of cystic pancreatic neoplasms has increasingly gained clinical attention due to their frequent incidental detection by cross-sectional imaging and their potential for progression to pancreatic cancer. Surgical resection is warranted for all mucinous cystic neoplasms, solid pseudopapillary neoplasms, and main-duct intraductal papillary mucinous neoplasms since these lesions harbor a major risk for malignant transformation. For branch-duct IPMN (BD-IPMN), the risk for malignancy is considerably lower so that some lesions may be safely followed while others require surgical resection. The clinical challenge lies in making the correct preoperative diagnosis and estimation of the risk of malignancy in BD-IPMN. Therefore, the existing evidence and current guidelines on the management of cystic lesions of the pancreas are summarized and controversially discussed from a surgical point of view.

Familial Pancreatic Cancer and the Future of Directed Screening

Pancreatic cancer (PC) is the third most common cause of cancer-related death in the United States and the 12th most common worldwide. Mortality is high, largely due to late stage of presentation and suboptimal treatment regimens. Approximately 10% of PC cases have a familial basis. The major genetic defect has yet to be identified but may be inherited by an autosomal dominant pattern with reduced penetrance. Several known hereditary syndromes or genes are associated with an increased risk of developing PC and account for approximately 2% of PCs. These syndromes include the hereditary breast-ovarian cancer syndrome, Peutz-Jeghers syndrome, familial atypical multiple mole melanoma, Lynch syndrome, familial polyposis, ataxia-telangiectasia, and hereditary pancreatitis. Appropriate screening using methods such as biomarkers or imaging, with endoscopic ultrasound and magnetic resonance imaging, may assist in the early detection of neoplastic lesions in the high-risk population. If these lesions are detected and treated before the development of invasive carcinoma, PC disease morbidity and mortality may be improved. This review will focus on familial PC and other hereditary syndromes implicated in the increased risk of PC; it will also highlight current screening methods and the future of new screening modalities.

Resection of benign side-branch intraductal papillary mucinous neoplasm of the pancreas-is long term follow-up indicated?: A case report and review of the literature

RATIONALE

Intraductal papillary mucinous neoplasms of the pancreas (IPMNs) are benign cystic tumors with a relevant risk of malignant transformation over time. Currently, follow-up after surgical resection of benign IPMNs remains controversial.

PATIENT CONCERNS

This is a case report of a 68-year-old male who underwent pancreatic head resection for a multicystic side-branch IPMN with low-grade epithelial dysplasia in March 2009 at the Katharinenhospital Stuttgart, Germany.

DIAGNOSES

During postoperative follow-up, a new solid, slightly hypodense lesion in the tail of the pancreas measuring 2.4 cm in diameter was diagnosed in July 2016. Preoperative staging revealed no signs of distant metastasis.

INTERVENTION

Subsequently, the patient underwent pancreatic tail resection including splenectomy. Histology revealed IPMN-associated adenocarcinoma of the pancreas pT3, pN1 (2/24), M0, R0.

OUTCOMES

Patients with IPMN bare a relatively high overall risk of developing pancreatic cancer. The 5-year incidence has been described to be as high as 6.9%. The current Consensus-Guidelines therefore recommend a structural life-time follow-up. In contrast, in 2015 the American Gastroenterological Association (AGA) explicitly states that follow-up is not recommended for resected benign IPMN. Currently, a general and international consensus is lacking.

LESSONS

The presented case demonstrates that even more than 5 years following resection of benign IPMN, pancreatic cancer can occur in a separate location of the pancreatic gland. We believe that IPMNs can be considered as indicator lesions for pancreatic cancer. Patients with resected side-branch IPMN should therefore undergo long term follow-up.

Diagnostic accuracy of diffusion restriction in intraductal papillary mucinous neoplasm of the pancreas in comparison with "high-risk stigmata" of the 2012 international consensus guidelines for prediction of the malignancy and invasiveness

Background It is debated whether diagnostic performance of diffusion-weighted imaging (DWI), which is widely used for detection and characterization of various malignant tumors, is comparable with high-risk stigmata of 2012 international consensus guidelines (ICG) for diagnosis of intraductal papillary mucinous neoplasms (IPMNs). Purpose To evaluate the diagnostic accuracy of diffusion restriction in IPMNs for prediction of malignancy and invasiveness in comparison with high-risk stigmata of 2012 ICG. Material and Methods This retrospective study was institutional review board approved and informed consent was waived. A total of 132 patients with surgically proven IPMNs (49 malignant, 83 benign) who underwent gadoxetic acid-enhanced magnetic resonance imaging (MRI), magnetic resonance cholangiopancreatography (MRCP), and DWI with a b-value of 0, 100, and 800 s/mm² using a 3.0 T MR system were included. Two radiologists independently evaluated imaging parameters of high-risk stigmata and worrisome features of 2012 ICG and diffusion restriction in IPMNs. Univariate and multivariate logistic regression analyses and McNemar's test were used for statistical analysis. Results The presence of diffusion restriction in IPMNs was the only independent imaging parameter for prediction of malignancy (odds ratio [OR], 11.98; 95% confidence interval [CI], 3.60-39.87; P < 0.001) and invasiveness (OR, 17.92; 95% CI, 3.91-82.03; P < 0.001) on multivariate analysis. The diagnostic accuracy and specificity of diffusion restriction were significantly improved compared to high-risk stigmata of 2012 ICG to prediction of malignant ( P = 0.006 and P < 0.001, respectively) or invasive IPMNs ( P = 0.009 and P = 0.015, respectively). Conclusion The diffusion restriction in IPMNs could be considered as another high-risk stigma of malignancy and predictor for invasiveness.

[Branch duct intraductal papillary mucinous neoplasm - surgical approach]

Due to increasing precision of modern imaging modalities, intraductal papillary mucinous neoplasms (IPMN) of the pancreas are found with increasing prevalence. Despite their malignant potential IPMN are often kept under surveillance and are not immediately resected. The 2012 International Consensus Guidelines of Fukuoka have been widely accepted for the management of IPMN. They recommend surgical resection for branch duct IPMN with "high risk stigmata", while branch duct IPMN with "worrisome features" should undergo observation without immediate resection. Consequently, patients with asymptomatic branch duct IPMN and a presumed low malignant potential mostly undergo primary surveillance to avoid surgery-related morbidity and mortality following pancreatic resection; however, with respect to the cumulative risk of malignant transformation over time, surgical resection might also be indicated for patients with branch duct IPMN with "worrisome features". This article discusses the indications for surgery and different options of resection of branch duct IPMN.

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.

Validation of the 2012 Fukuoka Consensus Guideline for Intraductal Papillary Mucinous Neoplasm of the Pancreas From a Single Institution Experience

OBJECTIVES

The 2012 Fukuoka consensus guideline has stratified the risks of malignant intraductal papillary mucinous neoplasm (IPMN) of the pancreas into "high-risk stigmata" (HRS) and "worrisome feature" (WF). This study aimed to evaluate its clinical validity based on a single institution experience.

METHODS

Eighty-nine patients who underwent surgical resection with pathological diagnosis of IPMN were retrospectively studied.

RESULTS

High-risk stigmata was significantly correlated with the prevalence of malignant IPMN as compared with WF. The positive predictive values of HRS and WF were 66.7% and 35.7% for branch duct IPMN and 80% and 38.1% for main duct IPMN, respectively. Univariate analysis indicated that all the factors in HRS and WF had statistical significance. Whereas multivariate analysis revealed only enhanced solid component (odds ratio [OR], 50.01; P = 0.008), presence of mural nodule (OR, 73.83; P < 0.001) and lymphadenopathy (OR, 20.85; P = 0.03) were independent predictors. Scoring HRS and WF by different numbers of positive factors resulted in improved predictive value. The area under the curve of HRS score was significantly lower than that of WF or HRS + WF score (0.680 vs 0.900 or 0.902, respectively; P < 0.001).

CONCLUSIONS

As supplementary to the 2012 Fukuoka guideline, we suggest that calculating scores of WF and HRS may have superior diagnostic accuracy in predicting malignant IPMN.

Pathology of Pancreatic Cancer Precursor Lesions

To better understand pancreatic ductal adenocarcinoma (PDAC) and improve its prognosis, it is essential to understand its origins. This article describes the pathology of the 3 well-established pancreatic cancer precursor lesions: pancreatic intraepithelial neoplasia, intraductal papillary mucinous neoplasm, and mucinous cystic neoplasm. Each of these precursor lesions has unique clinical findings, gross and microscopic features, and molecular aberrations. This article focuses on histopathologic diagnostic criteria and reporting guidelines. The genetics of these lesions are briefly discussed. Early detection and adequate treatment of pancreatic cancer precursor lesions has the potential to prevent pancreatic cancer and improve the prognosis of PDAC.

Analysis of clinical characteristics and treatment of pancreatic cystic tumors

Objective

To summarize experience in the diagnosis and treatment of pancreatic cystic neoplasms.

Methods

This is a retrospective study of 207 patients who were diagnosed with pancreatic cystic tumors at Peking Union Medical College Hospital between Jan 2009 and Mar 2014. Clinical data, such as clinical manifestations, radiological and pathological images and surgical recordings, were collected.

Results

Of the 207 included patients, females accounted for 76.81%, and the mean patient age was 52.04 years. Malignancy was more common in older patients who presented with marasmus and jaundice. Other risk factors included solid components in the tumor, a large tumor size, and elevated levels of tumor markers. Surgical treatment was required when a malignant tumor was suspected. The operation approach was selected based on the location, size and characteristics of the tumor. The position of the tumor relative to the pancreatic duct also played a significant role.

Conclusions

No specific symptoms were observed for the patients with pancreatic cystic tumors. Imaging played an important role in making a differential diagnosis. Furthermore, surgical treatment should be proposed for patients with significant symptoms and potentially malignant tumors. The tumor resection rate is high, suggestive of good prognosis.

Enucleation: A treatment alternative for branch duct intraductal papillary mucinous neoplasms

BACKGROUND

Small, asymptomatic, branch-duct intraductal papillary mucinous neoplasms of the pancreas are often kept under surveillance despite their malignant potential. The management of branch-duct intraductal papillary mucinous neoplasm is controversial with regard to indications and extent of any operative intervention. The present study aimed to evaluate enucleation as an alternative operative approach for branch-duct intraductal papillary mucinous neoplasms to exclude and prevent malignancy.

METHODS

For branch-duct intraductal papillary mucinous neoplasms of <30 mm in diameter and an acceptable distance from the main pancreatic duct, enucleation was considered as the operative approach of choice. All patients scheduled for enucleation of branch-duct intraductal papillary mucinous neoplasm on the basis of these features between January 2004 and September 2014 were analyzed. Among these, patients with successful enucleation were compared with those who were scheduled for enucleation but converted intraoperatively to pancreatic resection (intention-to-treat analysis). End points were hospital morbidity and mortality as well as histopathology and functional outcome at a mean follow-up of 32 months.

RESULTS

In the study, 115 patients with presumed branch-duct intraductal papillary mucinous neoplasm and the intention to perform pancreatic enucleation were included; 87 enucleations were performed in 74 patients. In 41 patients, enucleation was converted to a pancreatic resection (procedure-specific success rate 64%); indications for conversion included location or size (46%), presence of multicystic lesions (39%), or involvement of the main pancreatic duct (15%). Of the 74 patients with enucleation, 64 branch-duct intraductal papillary mucinous neoplasms revealed low- (85%), 11% moderate dysplasia-, and 4% high-grade dysplasia on histology. Among converted resections, 6 intraductal papillary mucinous neoplasms revealed high-grade dysplasia or invasive carcinoma (15%). Intention-to-treat analysis with patients converted to pancreatic resection showed that enucleations resulted in less blood loss (100 vs 400 mL) and a shorter operation time (146 vs 255 minutes; P < .001 each). Postoperative morbidity including postoperative pancreatic fistula was similar in both groups. No mortality occurred after enucleation; after formal resection, 1 patient died due to multiorgan failure. Both hospital stay (10 vs 14 days) and rates of postoperative endocrine and exocrine dysfunction rates were less after enucleation (P < .02 each). Intraductal papillary mucinous neoplasm-specific recurrence rates (3% vs 6%) were similar in both groups.

CONCLUSION

Enucleation is a safe procedure that can be performed successfully in a high proportion of branch-duct intraductal papillary mucinous neoplasms and should be considered instead of standard resections as an important function-preserving alternative. Limitations may occur due to malignancy, size, localization, multilocularity, or main-duct involvement requiring conversion to a formal, anatomic resection. Beside the advantages in the short-term course, functional outcome seems to be superior after enucleation, and intraductal papillary mucinous neoplasm-specific recurrence rates are not increased compared with standard resections, at least at a mean follow-up of 32 months.

Evaluating IPMN and pancreatic carcinoma utilizing quantitative histopathology

Intraductal papillary mucinous neoplasms (IPMN) are pancreatic lesions with uncertain biologic behavior. This study sought objective, accurate prediction tools, through the use of quantitative histopathological signatures of nuclear images, for classifying lesions as chronic pancreatitis (CP), IPMN, or pancreatic carcinoma (PC). Forty-four pancreatic resection patients were retrospectively identified for this study (12 CP; 16 IPMN; 16 PC). Regularized multinomial regression quantitatively classified each specimen as CP, IPMN, or PC in an automated, blinded fashion. Classification certainty was determined by subtracting the smallest classification probability from the largest probability (of the three groups). The certainty function varied from 1.0 (perfectly classified) to 0.0 (random). From each lesion, 180 ± 22 nuclei were imaged. Overall classification accuracy was 89.6% with six unique nuclear features. No CP cases were misclassified, 1/16 IPMN cases were misclassified, and 4/16 PC cases were misclassified. Certainty function was 0.75 ± 0.16 for correctly classified lesions and 0.47 ± 0.10 for incorrectly classified lesions (P = 0.0005). Uncertainty was identified in four of the five misclassified lesions. Quantitative histopathology provides a robust, novel method to distinguish among CP, IPMN, and PC with a quantitative measure of uncertainty. This may be useful when there is uncertainty in diagnosis.

MIB-1 labeling index, Ki-67, is an indicator of invasive intraductal papillary mucinous neoplasm

Despite strict criteria for the observation of intraductal papillary mucinous neoplasm (IPMN), it remains difficult to distinguish invasive IPMN from non-invasive IPMN. The aim of the present study was to identify an indicator of invasive IPMN. The present study retrospectively evaluated 53 patients (28 with non-invasive and 25 with invasive IPMN) who underwent resection of IPMN, and examined the usefulness of the MIB-1 labeling index as an indicator of invasive IPMN. The MIB-1 labeling indexes in patients with invasive IPMN were significantly higher compared with those with non-invasive IPMN (P<0.001). A receiver operating characteristic curve revealed that the area under the curve was 0.822. These results suggested that a cut-off level for the MIB-1 labeling index should be set to 15.5% to distinguish invasive from non-invasive IPMN. A multivariate analysis using a logistic regression model revealed the MIB-1 labeling index (hazard ratio, 18.692; 95% confidential interval, 4.171-83.760; P<0.001) and the existence of mural nodules (hazard ratio, 6.187, 95% confidential interval, 1.039-36.861; P=0.045) were predictive factors for invasive IPMN. However, no statistically significant differences were observed between patients with a lower MIB-1 labeling index and patients with a higher MIB-1 labeling index (P=0.798). The MIB-1 labeling index must be considered as a candidate for the classification of IPMN.

Main-duct Intraductal Papillary Mucinous Neoplasm: High Cancer Risk in Duct Diameter of 5 to 9 mm

OBJECTIVE

The 2012 international consensus guidelines for the management of intraductal papillary mucinous neoplasms (IPMN) recommend surgical treatment in main-duct IPMN patients with a main pancreatic duct (MPD) diameter of ≥10 mm. Aim of the present study was to analyze cancer risk in patients with an MPD diameter of less than 10 mm.

METHODS

All consecutive patients (prospective data protocol) with histological proof of IPMN who underwent surgery between January 2004 and December 2013 were included in the study. Clinical characteristics, particularly preoperative imaging with regard to morphology of the MPD, were correlated with final histopathology.

RESULTS

Among a total of 605 patients who underwent surgery for IPMN, there were 320 patients with MPD involvement, 238 patients with mixed-type IPMN, and 82 patients with main-duct IPMN alone. The total malignancy rate including high-grade dysplasia and invasive carcinoma in IPMNs with MPD involvement was 68%. When the MPD diameter was 5 to 9 mm, malignancy rate was 59%, whereas in MPD diameter more than 10 mm, it was 73%. No statistical correlations were observed between MPD diameter and clinical and/or IPMN features such as age, cyst location, mural nodules, serum tumor markers, or bilirubin.

CONCLUSIONS

Main-duct IPMNs with a MPD between 5 and 9 mm already bear a significant risk of malignancy. Therefore, surgical treatment is clearly indicated in patients with a MPD diameter of ≥5 mm and the 2012 guidelines should be discussed and adapted with regard to this topic.

Intraductal papillary mucinous neoplasm of the pancreas, one manifestation of a more systemic disease?

BACKGROUND

Several studies have demonstrated a high prevalence of extrapancreatic malignancies, and an association with autoimmune pancreatitis in patients with intraductal papillary mucinous neoplasm (IPMN). We hypothesized that IPMNs were associated with an increase rate of systemic diseases.

METHODS

From 1996 to 2013, a retrospective analysis of a prospectively collected database was performed and supplemented with electronic medical charts review.

RESULTS

Two hundred twenty extrapancreatic malignancies were found in 185 patients (22%) compared with expected 5% in the general population. Colorectal, lung, and renal cell carcinoma had significant observed/expected ratios (P < .0001). One hundred ten synchronous autoimmune diseases were found in 96 patients (11%). Systemic lupus erythematosus, rheumatoid arthritis, and inflammatory bowel disease showed statistically significant observed/expected ratios (P < .0001, .01, and <.0001, respectively). There was no impact of immunosuppressive treatment on the IPMN subtype and malignancy rate.

CONCLUSIONS

IPMN are associated with surprisingly high rates of autoimmune diseases suggesting that IPMN might be 1 manifestation of a more systemic disease.

Natural History and Management of Intraductal Papillary Mucinous Neoplasms: Current Evidence

Background

With the use of modern cross-sectional abdominal imaging modalities, an increasing number of cystic pancreatic lesions are identified incidentally. Although there is no pathological diagnosis available in most cases, it is believed that the majority of these lesions display small branch-duct intraductal papillary mucinous neoplasms (BD-IPMNs) of the pancreas. Even though a number of large clinical series have been published, many uncertainties remain with regard to this entity of mucinous cystic neoplasms.

Methods

Systematic literature review.

Results

Main-duct (MD) and mixed-type IPMNs harbor a high risk of malignant transformation. It is conceivable that most IPMNs with involvement of the main duct tend to progress to invasive carcinoma over time. Thus, formal oncologic resection is the treatment of choice in surgically fit patients. In contrast, the data regarding BD-IPMN remain equivocal, resulting in conflicting concepts. To date, it is not clear whether and which BD-IPMNs progress to carcinoma and how long this progression takes.

Conclusion

While patients with MD-IPMNs should undergo surgical resection if comorbidities and life expectancy permit this, the management of small BD-IPMNs remains controversial. Population-based studies with long-term follow-up are needed to define which cohort of patients can be observed safely without immediate resection.

Quality assessment of the guidelines on cystic neoplasms of the pancreas

BACKGROUND

Though cystic pancreatic neoplasms (CPNs) are being increasingly detected, their evaluation and management are still debated and have lead to publication of multiple guidelines for diagnostic work-up, indications for resection, and non-operative management with follow-up strategies of CPNs.

AIMS

To analyze available guidelines in order to evaluate their overall quality and clinical applicability, indications for surgical resection and its extent, modalities and timing of follow-up when non-operative management is indicated.

METHODS

After a systematic search of the English literature, we selected eight guidelines for assessment according to the Appraisal of Guidelines, Research and Evaluation in Europe (AGREE) II instrument.

RESULTS

One guideline received the lower AGREE score regarding the "scope and purpose", "rigor of development" and "clarity and presentation" domains, whereas one received the best score for "stakeholder involvement" domain. No differences were found among different guidelines regarding the "applicability". The overall quality assessment score showed that only two guidelines were significantly lower than the others. According to the practical utilization recommendation score, four guidelines were considered as having full applicability in clinical practice.

CONCLUSION

Existing guidelines provide adequate guidance, at least with the present knowledge, for the management of cystic pancreatic lesions; however, not any one was satisfactory to all aspects related to the management of CPN. An update of the existing guidelines should be considered if and when more evidence-based data are available.

Total pancreatectomy for primary pancreatic neoplasms: renaissance of an unpopular operation

OBJECTIVE

To assess the long-term survival and quality of life in total pancreatectomies and to identify risk factors for perioperative morbidity and mortality.

BACKGROUND

Total pancreatectomy may be required in locally advanced or centrally located pancreatic neoplasms to achieve complete tumor clearance, but available data on short- and long-term results are limited.

METHODS

A total of 434 consecutive total pancreatectomies for primary pancreatic or periampullary tumors were performed between October 2001 and September 2012 at the authors' institution and were prospectively documented and analyzed. Long-term outcome was assessed using Kaplan-Meier and quality of life analysis (EORTC-QLQ-C30 and PAN26). Uni- and multivariate analysis was performed to identify perioperative risk factors and predictors for long-term survival.

RESULTS

Extended total pancreatectomies were performed in 54% of cases, with arterial and portal vein resections in 15% and 32%, respectively. Overall 30-day and in-hospital mortality rates were 3.7% and 7.8%, respectively. High blood loss, long operative time, and arterial resections were independently associated with increased perioperative mortality (P ≤ 0.018). In malignant disease, median and 5-year survival were good for standard total pancreatectomies (28.6 months and 24.3%, respectively) and were significantly impaired after vascular resections (P < 0.001). Poor tumor grading, high American Joint Commission on Cancer tumor stage, age more than 70 years, and an R1 resection were independent prognostic parameters. Long-term global quality of life was comparable with a matched healthy control group.

CONCLUSIONS

Standard total pancreatectomy, if needed, is associated with good long-term outcome in pancreatic cancer. Marked surgical morbidity and impaired survival associated with vascular resections reflect the invasiveness of extended total pancreatectomies and the underlying advanced malignant disease.

Pancreatic main-duct involvement in branch-duct IPMNs: an underestimated risk

OBJECTIVES

This study aimed to analyze a large single-center population of resected intraductal papillary mucinous neoplasms (IPMN) of the pancreas with respect to risk factors of malignant transformation.

BACKGROUND

There is international consensus that main-duct (MD) as well as mixed-type IPMNs should be treated surgically due to a high risk of malignancy. In contrast, there is an ongoing controversy about surgery of branch-duct type IPMN (BD-IPMN).

METHODS

All consecutive patients who underwent surgery for IPMN between January 2004 and December 2012 were included. Clinical characteristics and preoperative imaging were correlated with histopathological features.

RESULTS

A total of 512 patients underwent pancreatic surgery and had a histological proof of IPMN. According to preoperative imaging, 74 patients had MD-IPMN (14%), 205 mixed-type (40%), and 233 suspected BD-IPMN (46%). On histopathology, 162 of 512 patients revealed low-grade, 105 moderate, and 52 high-grade dysplasia. One hundred ninety-three IPMN patients (38%) suffered from invasive carcinoma. Among invasive IPMNs, the majority (58%) were mixed-type lesions according to preoperative imaging. Of 141 Sendai negative BD-IPMNs, a malignancy rate of 18% (high-grade dysplasia and invasive carcinoma) was found. Most interesting, 29% of suspected BD-IPMNs (67/233) revealed histological involvement of the main pancreatic duct not evident in preoperative imaging.

CONCLUSIONS

All subtypes of IPMNs display a relevant risk for malignant transformation. By abdominal imaging, many IPMNs are misclassified as BD-IPMNs but reveal mixed-type lesions in histopathology. Because currently available preoperative diagnostics are not sufficient to reliably diagnose BD-IPMNs, surgical resection for suspected small branch-duct IPMN should be considered in patients fit for surgery.

Pancreatic intraductal papillary mucinous neoplasm--where is the challenge?

Cystic lesions of the pancreas are increasingly recognized due to the widespread use of modern abdominal imaging technologies. The majority of these lesions display pseudocysts and mucinous cystic neoplasms. In contrast to pseudocysts, it is well established that mucinous cystic neoplasms of the pancreas exhibit a significant potential for malignant transformation over time. Among mucinous cystic tumors, the most frequently observed entity is pancreatic intraductal papillary mucinous neoplasm (IPMN). IPMNs are characterized by cystic dilation of pancreatic ducts and the production of mucus and by an adenoma-carcinoma sequence eventually culminating in invasive carcinoma in some patients. Due to the high risk of harboring malignancy, there is international consensus that IPMNs with involvement of the main pancreatic duct should be recommended for surgical resection. To date, the indication for surgery of branch-duct IPMNs is controversially discussed because of the overall lower risk of malignant transformation compared to main-duct IPMNs. Particularly for small and asymptomatic side-branch IPMNs, the indication for surgical resection remains challenging. In addition to the international consensus guidelines, a number of potential preoperative features predicting malignant transformation have been discussed recently. Moreover, novel surgical pancreatic parenchyma-sparing techniques such as enucleations or segmental pancreatic resections have been reported in order to treat IPMNs. The present article aims to demonstrate the current scientific knowledge in this field and to highlight the current controversy.

Implications of imaging criteria for the management and treatment of intraductal papillary mucinous neoplasms - benign versus malignant findings

OBJECTIVES

Evaluation of computed tomography (CT) and magnetic resonance imaging (MRI) for differentiation of pancreatic intraductal papillary mucinous neoplasm (IPMN) subtypes based on objective imaging criteria.

METHODS

Fifty-eight patients with 60 histologically confirmed IPMNs were included in this retrospective study. Eighty-three imaging studies (CT,n = 42; MRI,n = 41) were analysed by three independent blinded observers (O1-O3), using established imaging criteria to assess likelihood of malignancy (-5, very likely benign; 5, very likely malignant) and histological subtype (i.e., low-grade (LGD), moderate-grade (MGD), high-grade dysplasia (HGD), early invasive carcinoma (IPMC), solid carcinoma (CA) arising from IPMN).

RESULTS

Forty-one benign (LGD IPMN,n = 20; MGD IPMN,n = 21) and 19 malignant (HGD IPMN,n = 3; IPMC,n = 6; solid CA,n = 10) IPMNs located in the main duct (n = 6), branch duct (n = 37), or both (n = 17) were evaluated. Overall accuracy of differentiation between benign and malignant IPMNs was 86/92 % (CT/MRI). Exclusion of overtly malignant cases (solid CA) resulted in overall accuracy of 83/90 % (CT/MRI). The presence of mural nodules and ductal lesion size ≥30 mm were significant indicators of malignancy (p = 0.02 and p < 0.001, respectively).

CONCLUSIONS

Invasive IPMN can be identified with high confidence and sensitivity using CT and MRI. The diagnostic problem that remains is the accurate radiological differentiation of premalignant and non-invasive subtypes.

KEY POINTS

• CT and MRI can differentiate benign from malignant forms of IPMN. • Identifying (pre)malignant histological IPMN subtypes by CT and MRI is difficult. • Overall, diagnostic performance with MRI was slightly (not significantly) superior to CT.

Intraductal papillary mucinous neoplasm: clinical surveillance and management decisions

Intraductal papillary mucinous neoplasm (IPMN) of the pancreas is a relatively rare cystic neoplasm. Although most IPMNs appear to be benign and may be managed by surveillance, all IPMNs are considered premalignant lesions with malignant potential. As such, current efforts are focused on identifying those neoplasms that are at high risk for malignancy to optimize treatment strategy and outcome. IPMNs with invasive carcinoma have clinical outcomes that approach those of conventional pancreatic ductal adenocarcinoma. Management guidelines recommend surgical resection for IPMNs with high-risk imaging or cytologic features. The role of adjuvant therapy is unclear, and we review the evidence for chemoradiation here. Some studies suggest adjuvant chemoradiation may have the greatest impact in malignant IPMNs with adverse histologic features, that is, lymph node metastasis at the time of diagnosis or positive surgical margins. As more IPMNs are recognized and treated, more evidence will accumulate to guide clinicians regarding appropriate use of radiotherapy in the management of IPMN.

The natural history of main duct-involved, mixed-type intraductal papillary mucinous neoplasm: parameters predictive of progression

OBJECTIVE

As such, the natural history of MPD-involved IPMN is poorly understood.

BACKGROUND

The high-risk of malignancy associated with main pancreatic duct (MPD)-involved intraductal papillary mucinous neoplasm (IPMN) has been established by surgical series. The International Consensus Guidelines recommend surgical resection of MPD-involved IPMN in fit patients.

METHODS

A review of a prospectively collected database (1992-2012) of patients with IPMN undergoing primary surveillance was performed. Invasive progression was defined as invasive carcinoma on pathology and/or positive cytopathology. Analyses included univariate, logistic regression, and receiver operating characteristic curve analyses.

RESULTS

A total of 503 patients with IPMN underwent primary surveillance, 70 for MPD-involved, mixed-type IPMN. Indications for intensive surveillance of these 70 high-risk patients were comorbidities, patient choice, and early/borderline MPD dilation (42%, 51%, and 7%, respectively). Mean follow-up was 4.7 years. Nine patients (13%) progressed at a mean of 3.5 (range, 1-9) years during follow-up. Univariate analyses yielded weight loss, interval (from isolated branch-duct IPMN) to MPD involvement, diffuse MPD dilation, increase of MPD diameter, absence of extra pancreatic cysts, elevated serum CA19-9 levels, and elevated serum alkaline phosphatase levels as significant. Maximum MPD and/or branch-duct diameter were not significant. In logistic regression, diffuse MPD dilation, serum CA19-9 and serum alkaline phosphatase levels, and absence of extra pancreatic cysts were predictors of invasiveness. The receiver operating characteristic curve indicated that the combination of these 4 factors achieved an accuracy of 98% in predicting progression.

CONCLUSIONS

Primary surveillance of mixed-type IPMN may be a reasonable strategy in select patients. Diffuse MPD dilation, serum CA19-9, serum alkaline phosphatase, and absence of extrapancreatic cysts predict patients likely to progress during primary surveillance.

International Consensus Guidelines parameters for the prediction of malignancy in intraductal papillary mucinous neoplasm are not properly weighted and are not cumulative

BACKGROUND

The International Consensus Guidelines (ICG) stratify risk for malignancy in patients with intraductal papillary mucinous neoplasm (IPMN) into three progressive categories according to whether patients show 'no criteria', 'worrisome features' (WFs) or 'high-risk stigmata' (HRS).

OBJECTIVES

This study was conducted to test the hypothesis that type (clinical versus radiological) and quantity of ICG WFs and HRS carry unequal weight and are not cumulative in the prediction of risk for malignancy or invasiveness in IPMN.

METHODS

A retrospective review of a prospectively maintained database of patients who underwent surgical resection for IPMN at a single, university-based medical centre during 1992-2012 was performed. Differences that achieved a P-value of <0.05 were considered significant.

RESULTS

Of 362 patients, 340 were eligible for entry into the study and were categorized as demonstrating no criteria (n = 70), WFs (n = 185) or HRS (n = 85). Patients in the WFs group had higher rates of malignant and invasive IPMN than those in the no-criteria group [26.5% versus 4.3% (P < 0.0001) and 15.7% versus 4.3% (P = 0.02), respectively]. Patients in the HRS group had higher rates of malignant and invasive IPMN than those in the WFs group [56.5% versus 26.5% (P = 0.0001) and 42.4% versus 15.7% (P = 0.0001), respectively]. When radiological parameters only were considered for WFs versus HRS, no difference was found in rates of malignant or invasive IPMN. By contrast, when clinical parameters only were considered, patients in the HRS group had higher rates of malignant or invasive IPMN [66.7% versus 8.1% (P = 0.04) and 66.7% versus 2.7% (P = 0.01), respectively]. There was no stepwise increase in rates of malignant or invasive IPMN with the number of WFs. However, patients with only one WF had a lower risk for malignancy than patients with two or more WFs.

CONCLUSIONS

The type and quantity of ICG WFs and HRS carry unequal weight and are not cumulative in the prediction of risk for malignancy or invasiveness in IPMN.

Moving beyond morphology: new insights into the characterization and management of cystic pancreatic lesions

The frequency of detection of cystic pancreatic lesions with cross-sectional imaging, particularly with multidetector computed tomography, magnetic resonance (MR) imaging, and MR cholangiopancreatography, is increasing, and many of these cystic pancreatic lesions are being detected incidentally in asymptomatic patients. Because there is considerable overlap in the cross-sectional imaging findings of cystic pancreatic lesions, and because many of these lesions being detected are smaller than 3 cm in diameter and lack any specific cross-sectional imaging features, it has become difficult to make informed decisions about patient management when the precise diagnosis remains uncertain. This article presents the limitations of cross-sectional imaging in patients with cystic pancreatic lesions, details advances in knowledge of the genomic and epigenomic changes that lead to progression of carcinogenesis, outlines the current understanding of the natural history of mucinous cystic lesions, and includes the current use and future potential of novel tumor markers and molecular analysis to characterize cystic pancreatic lesions more precisely. The need to move beyond cross-sectional imaging morphology and toward the use of new techniques to diagnose these lesions accurately is emphasized. An algorithm that uses these techniques is proposed and will hopefully lead to improved patient management.

Endoscopic techniques for diagnosis and therapy of pancreatic intraductal papillary mucinous neoplasm

Intraductal papillary mucinous neoplasm (IPMN) of the pancreas is a cystic neoplasm with potential malignancy. In the past, screening of IPMN depended on traditional imaging examinations, such as transabdominal ultrasonography and computed tomography (CT). With the development of endoscopic techniques, endoscopic ultrasound (EUS), endoscopic retrograde cholangiopancreatography (ERCP) and other endoscopic techniques are becoming significant diagnostic methods for IPMN. Meanwhile, endoscopic interventional therapy with the advantage of minimal invasiveness has been used to treat some patients who cannot tolerate or refuse surgery. This paper elucidates the advances in diagnosis and therapy of pancreatic IPMNs using endoscopic techniques.

Nonoperative management of main pancreatic duct-involved intraductal papillary mucinous neoplasm might be indicated in select patients

BACKGROUND

Although the natural history of intraductal papillary mucinous neoplasm (IPMN) remains unclear, large surgical series have reported malignancy in 40% to 90% of main pancreatic duct (MPD)-involved IPMN. Accordingly, the 2012 International Consensus Guidelines recommend surgical resection in patients with suspected MPD involvement. We hypothesized that nonoperative management of select patients with suspected MPD-involved IPMN might be indicated.

STUDY DESIGN

From 1992 to 2012, 362 patients underwent surgical resection for pathologically confirmed IPMN at a single academic center. A retrospective review of prospectively collected data was performed. Main pancreatic duct involvement was suspected with an MPD diameter ≥5 mm on preoperative imaging. A multivariate analysis was conducted to assess predictors of malignancy.

RESULTS

Of 362 patients, 334 had complete data for analysis. Main pancreatic duct involvement was suspected preoperatively in 171 patients. Final pathology revealed 20% high-grade dysplastic and 27% invasive IPMN (47% malignant). Preoperative cytopathology and serum carbohydrate antigen 19-9 independently predicted malignancy (p = 0.003 and p = 0.002, respectively) and invasiveness (p < 0.0001 and p = 0.001, respectively). Patients with both negative preoperative cytopathology and normal serum carbohydrate antigen 19-9 (ie, double negatives) had a lower rate of malignancy and invasiveness (28% and 8% vs 58% and 38%; p < 0.0001). The MPD diameter did not predict malignancy or invasiveness (p = 0.36 and p = 0.46, respectively).

CONCLUSIONS

Patients with suspected MPD-involved IPMN have a highly variable rate of malignancy. Despite recent International Consensus Guidelines recommendations, these data suggest that MPD diameter is not an optimal gauge of malignant risk. Nonoperative management of suspected MPD-involved IPMN in select patients, particularly double negatives, might be indicated. Depending on age and comorbidity, operative risk might outweigh the risk of malignant progression in these patients.

IPMN: surgical treatment

PURPOSE

Cystic pancreatic tumors are being detected more frequently, and particularly, intraductal papillary mucinous neoplasia (IPMN) has recently attracted increased attention. The detection rate of IPMN has increased over the last decade; however, management of this neoplasm remains controversial.

METHODS

Based on a review of the relevant literature and the international guidelines, we discuss the diagnostic evaluation of IPMN, its treatment, and prognosis.

RESULTS

While IPMN represents only a distinct minority of all pancreatic cancers, they appear to be a relatively frequent neoplastic form of pancreatic cystic neoplasm. It may not be possible to differentiate main duct disease from branch duct disease (MD-IPMN vs. BD-IPMN) prior to surgery. This distinction has not only an impact on treatment but also on prognosis, as MD-IPMN is more often malignant. IPMN has updated consensus guideline indications for conservative and surgical resection.

CONCLUSIONS

Since patients with IPMN of the pancreas are at risk of developing recurrent IPMN and pancreatic ductal adenocarcinoma in the remnant pancreas and extrapancreatic malignancies, early recognition, treatment, and systemic surveillance are of great importance. No conclusions can be drawn from the available evidence with respect to the efficacy of surveillance and follow-up treatment programs. A better understanding of the natural course of IPMN and the biology of pancreatic cancer is mandatory to enable further diagnostic and treatment improvements.

Pancreatic surgery: beyond the traditional limits

Pancreatic cancer is one of the five leading causes of cancer death for both males and females in the western world. More than 85 % pancreatic tumors are of ductal origin but the incidence of cystic tumors such as intrapapillary mucinous tumors (IPMN) or mucinous cystic tumors (MCN) and other rare tumors is rising. Complete surgical resection of the tumor is the mainstay of any curative therapeutic approach, however, up to 40 % of patients with potentially resectable pancreatic cancer are not offered surgery. This is despite 5-year survival rates of up to 40 % or even higher in selected patients depending on tumor stage and histology. Standard procedures for pancreatic tumors include the Kausch-Whipple- or pylorus-preserving Whipple procedure, and the left lateral pancreatic resection (often with splenectomy), and usually include regional lymphadenectomy. More radical or extended pancreatic operations are becoming increasingly utilised however and we examine the data available for their role. These operations include major venous and arterial resection, multivisceral resections and surgery for metastatic disease, or palliative pancreatic resection. Portal vein resection for local infiltration with or without replacement graft is now well established and does not deleteriously affect perioperative morbidity or mortality. Arterial resection, however, though often technically feasible, has questionable oncologic impact, is not without risk and is usually reserved for isolated cases. The value of extended lymphadenectomy is frequently debated; the recent level I evidence demonstrates no advantage. Multivisceral resections, i.e. tumors, often in the tail of the pancreas, with invasion of the colon or stomach or other surrounding tissues, while associated with an increased morbidity and a longer hospital stay, do however show comparable mortality-and survival rates to those without such infiltration and therefore should be performed if technically feasible. Routine resection for metastatic disease however does not seem to show any advantage over palliative treatment but may be an option in selected patients with easily removable metastases. In conclusion pancreatic surgery beyond the traditional limits is established in tumors infiltration the venous system and may be a considered approach in selected patients with locally infiltrating pancreatic cancer or metastasis.