Intraductal papillary mucinous neoplasms of the pancreas with concurrent pancreatic and periampullary neoplasms

Percentage of Pancreatic Cysts on MRI With a Pancreatic Carcinoma: Systematic Review and Meta-Analysis

BACKGROUND

Pancreatic cystic lesions (PCLs) are frequent on MRI and are thought to be associated with pancreatic adenocarcinoma (PDAC) necessitating long-term surveillance based on older studies suffering from selection bias.

PURPOSE

To establish the percentage of patients with PCLs on MRI with a present or future PDAC.

STUDY TYPE

Systematic review, meta-analysis.

POPULATION

Adults with PCLs on MRI and a present or future diagnosis of PDAC were eligible. MEDLINE, EMBASE, Cochrane Central Register of Controlled Trials, and Scopus were searched to April 2022 (PROSPERO:CRD42022320502). Studies limited to PCLs not requiring surveillance, <100 patients, or those with a history/genetic risk of PDAC were excluded.

FIELD STRENGTH/SEQUENCE

≥1.5 T with ≥1 T2-weighted sequence.

ASSESSMENT

Two investigators extracted data, with discrepancies resolved by a third. QUADAS-2 assessed bias. PDAC was diagnosed using a composite reference standard.

STATISTICAL TESTS

A meta-analysis of proportions was performed at the patient-level with 95% confidence intervals (95% CI).

RESULTS

Eight studies with 1289 patients contributed to the percentage of patients with a present diagnosis of PDAC, and 10 studies with 3422 patients to the percentage with a future diagnosis. Of patients with PCLs on MRI, 14.8% (95% CI 2.4-34.9) had a PDAC at initial MRI, which decreased to 6.0% (2.2-11.3) for studies at low risk of bias. For patients without PDAC on initial MRI, 2.0% (1.1-3.2) developed PDAC during surveillance, similar for low risk of bias studies at 1.9% (0.7-3.6), with no clear trend of increased PDAC for longer surveillance durations. For patients without worrisome features or high-risk stigmata, 0.9% (0.1-2.2) developed PDAC during surveillance. Of 10, eight studies had a median surveillance ≥3 years (range 3-157 months). Sources of bias included retrospectively limiting PCLs to those with histopathology and inconsistent surveillance protocols.

DATA CONCLUSION

A low percentage of patients with PCLs on MRI develop PDAC while on surveillance. The first MRI revealing a PCL should be scrutinized for PDAC.

LEVEL OF EVIDENCE

3 TECHNICAL EFFICACY: Stage 2.

Metabolic Syndrome Accelerates the Age-Related Increase of Intraductal Papillary Mucinous Neoplasm of the Pancreas

OBJECTIVES

Aging is associated with a high prevalence of pancreatic cysts and intraductal papillary mucinous neoplasms (IPMNs). Metabolic syndrome (MS) may increase the risk of neoplasms, including those that develop in the pancreas. However, the influence of factors associated with MS on the development of IPMN remains unclear.

METHODS

A total of 9363 patients who underwent abdominal ultrasound examinations between April 2012 and May 2013 were included in this study. Multivariate logistic regression analysis was performed to identify factors associated with the presence of IPMN by age.

RESULTS

Pancreatic cysts were detected in 198 of 9363 patients, of whom 129 were found to have IPMNs. The presence of IPMN significantly correlated with age (10-year increments; odds ratio, 2.73; 95% CI, 2.28-3.29; P < 0.001). High body mass index, history of smoking, hyperlipidemia, hypertension, and MS were associated with a higher prevalence of IPMN with advancing age. In multivariate analysis, the presence of IPMN was more frequent in elderly patients with MS (odds ratio, 3.14; 95% CI, 3.14-6.72; P = 0.003).

CONCLUSIONS

The present study suggests that the incidence of IPMN increases with age and is accelerated in the presence of MS.

Update on Prevalence of Pain in Patients with Cancer 2022: A Systematic Literature Review and Meta-Analysis

Experiencing pain and insufficient relief can be devastating and negatively affect a patient's quality of life. Developments in oncology such as new treatments and adjusted pain management guidelines may have influenced the prevalence of cancer pain and severity in patients. This review aims to provide an overview of the prevalence and severity of pain in cancer patients in the 2014-2021 literature period. A systematic literature search was performed using the databases PubMed, Embase, CINAHL, and Cochrane. Titles and abstracts were screened, and full texts were evaluated and assessed on methodological quality. A meta-analysis was performed on the pooled prevalence and severity rates. A meta-regression analysis was used to explore differences between treatment groups. We identified 10,637 studies, of which 444 studies were included. The overall prevalence of pain was 44.5%. Moderate to severe pain was experienced by 30.6% of the patients, a lower proportion compared to previous research. Pain experienced by cancer survivors was significantly lower compared to most treatment groups. Our results imply that both the prevalence of pain and pain severity declined in the past decade. Increased attention to the assessment and management of pain might have fostered the decline in the prevalence and severity of pain.

Long-standing diabetes mellitus increases concomitant pancreatic cancer risk in patients with intraductal papillary mucinous neoplasms

BACKGROUND

When monitoring patients with an intraductal papillary mucinous neoplasm (IPMN), it is important to consider both IPMN-derived carcinoma and concomitant ductal adenocarcinoma (PDAC). The latter is thought to have a poorer prognosis. We retrospectively analyzed the risk factors for concomitant PDAC in IPMN.

METHODS

In total, 547 patients with pancreatic cysts, including IPMNs inappropriate for surgery on initial diagnosis, encountered from April 2005 to June 2019, were reviewed. We performed surveillance by imaging examination once or twice a year.

RESULTS

Five IPMNs with high-grade dysplasia and one IPMN associated with invasive carcinoma were encountered. In comparison, 14 concomitant PDACs were encountered. The prognosis was very poor for concomitant PDACs. All 14 PDAC patients had IPMNs. In patients with IPMNs, long-standing diabetes mellitus was the only significant risk factor for concomitant PDAC in both univariate and multivariate analyses (P < 0.001 and P < 0.01, respectively). Furthermore, patients with IPMNs and diabetes mellitus had a high frequency of concomitant PDACs (9.5%, 9/95) in a median 48-month surveillance period.

CONCLUSIONS

When monitoring IPMNs, the development of not only IPMN-derived carcinomas but also concomitant PDACs should be considered. During this period, it may be prudent to concentrate on patients with other risk factors for PDAC, such as long-standing diabetes mellitus.

EUS-guided intra-tumoral therapies

EUS-guided treatments for focal tumor lesions has been developed since 20 years using at onset of the technique mainly local and guided alcohol injection [1-4]. Pancreatic tumors are the most assessed targeted lesions for EUS treatment because of their accessibility and because EUS management could be a safe alternative to surgery. More and more pancreatic tumors are discovered mainly fortuitously due to the advances in conventional imaging (abdominal ultrasound, CT, MRI) resulting in the question of surgical management of an asymptomatic pancreatic lesion ("incidentaloma") [5-8]. The lesions detected include mostly pancreatic cystic neoplasms (PCN) and neuroendocrine tumors (NET) mainly well differentiated. Clinically, NET are mostly non-functional and do not induce secretory disorders [5-8]. Once their nature is yielded by diagnostic tests like EUS-FNA, incidental nonfunctional NET currently lead to difficult management when their largest diameter is less than 2 cm [2,4,9,10]. EUS-guided treatment for pancreatic adenocarcinoma have also been developed with recent prospective observational study and randomized control study [11,12]. Thus, therapeutic surgical choices could be challenged by EUS- guided treatment [2,4,9].

Pancreatic CT density is an optimal imaging biomarker for earlier detection of malignancy in the pancreas with intraductal papillary mucinous neoplasm

BACKGROUND

Intraductal papillary mucinous neoplasms (IPMNs) are typically detected as incidental findings by computed tomography (CT); however, the conventional surveillance is not valid for the early detection of concomitant pancreatic cancer. The pancreas of IPMN is often accompanied by fatty infiltration in the parenchyma, and pancreatic fatty infiltration could be evaluated by pancreatic CT density (pancreatic index, PI). We aimed to investigate whether PI could be an imaging biomarker for the early prediction of malignancies in the pancreas with IPMN.

METHODS

Two different cohorts were investigated. (Investigation cohort): A total of 1137 patients with initially low-risk IPMN were compensated by initial IPMN findings, and 2 groups (malignancy/possible benign, 50 cases each) were investigated for yearly changes in PI and for the cutoff value of PI indicating the development of malignancies. (Validation cohort): To validate the cutoff value, 256 patients radiologically suspected of having IPMNs were investigated.

RESULTS

(Investigation-cohort): The malignancy group showed a gradual decrease in PI every year, and PI significantly differed among the 2 groups 1 year prior to the last investigation. The cutoff value of PI was set at 0.65. (Validation-cohort): A total of 55% of the patients with a PI below the cutoff value had malignancy in the pancreas, including concomitant pancreatic cancer, and the cutoff value was the most significant risk factors for the development of malignancies in the pancreas compared to the conventional risk factors for IPMN.

CONCLUSIONS

Decreasing PI would be an optimal imaging biomarker for earlier detection of malignancies in the pancreas with IPMN.

Pancreatic Cystic Lesions and Malignancy: Assessment, Guidelines, and the Field Defect

The widespread use of high-spatial-resolution cross-sectional imaging has led to an increase in detection of incidental pancreatic cystic lesions. These lesions are a diverse group, ranging from indolent and premalignant lesions to invasive cancers. The diagnosis of several of these lesions can be suggested on the basis of their imaging appearance, while many other lesions require follow-up imaging and/or aspiration. The smaller cystic lesions, often branch-duct intraductal papillary mucinous neoplasms, have overlapping imaging characteristics that make diagnostic assessment of the natural history and malignancy risk confusing. Expert panels have developed societal guidelines, based on a consensus, for surveillance of these lesions. However, these guidelines are often inconsistent and are constantly evolving as additional scientific data are accumulated. Identification of features associated with increased risk of malignancy is important for proper management. The concept of field defect, whereby pancreatic adenocarcinoma develops at a site different from the site of the pancreatic cyst, adds to the complexity of screening guidelines. As a result of the differences in guidelines, key stakeholders (eg, radiologists, gastroenterologists, and surgeons) must review and come to a consensus regarding which guideline, or combination of guidelines, to follow at their individual institutions. Standardized reporting and macros are helpful for ensuring the uniformity of interpretations. Radiologists play a critical role in the detection and characterization of pancreatic cystic lesions, in the follow-up recommendations for these lesions, and in the detection of associated cancer. An invited commentary by Zaheer is available online. Online supplemental material is available for this article. ^©RSNA, 2021.

Case report: composite pancreatic intraductal papillary mucinous neoplasm and neuroendocrine tumor: a new mixed neuroendocrine-non-neuroendocrine neoplasm?

BACKGROUND

Mixed neuroendocrine-non-neuroendocrine neoplasms (MiNEN) of the pancreas are extremely rare. Their pathogenesis and molecular landscape are largely unknown. Here, we report a case of mixed pancreatic intraductal papillary mucinous neoplasm (IPMN) and well-differentiated neuroendocrine tumor (NET) and identify its genetic alterations by next-generation sequencing (NGS).

CASE PRESENTATION

A fifty-year-old male was admitted into the hospital for evaluation of a pancreatic lesion detected during a routine examination. Abdominal ultrasound indicated a hypoechoic mass of 2.6 cm at the head of the pancreas. Malignancy was suspected and partial pancreatectomy was performed. Thorough histopathological examination revealed a mixed IPMN-NET. In some areas, the two components were relatively separated, whereas in other areas IPMN and NET grew in a composite pattern: The papillae were lined with epithelial cells of IPMN, and there were clusters of NET nests in the stroma of papillary axis. NGS revealed shared somatic mutations (KRAS, PCK1, MLL3) in both components. The patient has been uneventful 21 months after the surgery.

CONCLUSIONS

Our case provides evidence of a common origin for mixed IPMN-NET with composite growth features. Our result and literature review indicate that KRAS mutation might be a driver event underlying the occurrence of MiNEN. We also recommend the inclusion of mixed non-invasive exocrine neoplasms and neuroendocrine neoplasms into MiNEN.

Laparoscopic distal pancreatectomy for intraductal papillary mucinous neoplasm-associated pancreatic cancer: A case report

Introduction and importance

Intraductal papillary mucinous neoplasm (IPMN) of the pancreas is often found incidentally during examination for other diseases. In addition to the risk of malignant transformation, patients with IPMN are at risk of developing pancreatic cancer. We report a case of pancreatic tail cancer that developed separately from a preexisting IPMN after minimally invasive esophagectomy for cancer of the esophagogastric junction and was resected successfully by laparoscopic distal pancreatectomy.

Case presentation

A 72-year-old man underwent thoracoscopic and laparoscopic esophagectomy for esophagogastric junction cancer. He had undergone surgery for ascending colon cancer 20 years ago. At that time, IPMN was confirmed in the pancreatic body by a preoperative examination. Computed tomography was regularly performed for postoperative work-up and follow-up of the IPMN, and a solid lesion with cystic components was detected in the pancreatic tail 9 months after the operation. On detailed examination, pancreatic ductal adenocarcinoma concomitant with IPMN, accompanied by a retention cyst, was considered. Laparoscopic distal pancreatectomy was successfully performed after neoadjuvant chemotherapy. Pathological diagnosis of the lesion in the pancreatic tail was of an invasive intraductal papillary mucinous carcinoma (ypT3ypN0yM0 ypStageIIA).

Clinical discussion

If an IPMN is detected during preoperative examination for malignancies of other organs, careful follow-up is necessary due to the high risk of pancreatic cancer development. Furthermore, initial operation with minimally invasive surgery may reduce adhesion and facilitate subsequent surgeries.

Conclusion

We have provided evidence that supports the importance of a careful follow-up of IPMNs, even if they are low risk.

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Intraductal papillary mucinous neoplasm of the pancreas is found incidentally.

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A pre-existing neoplasm led to pancreatic tail cancer in one patient.

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Due to careful follow-up of the neoplasm, the secondary cancer was detected rapidly.

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It was resected successfully by laparoscopic distal pancreatectomy.

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Careful follow is necessary if this neoplasm is detected.

Synchronous detection of pancreatic adenocarcinoma and paraganglioma in a Whipple resection specimen

We report a case of a pancreatic ductal adenocarcinoma (PDAC) presenting synchronously with a paraganglioma (PGL) in a Whipple reaction specimen. The patient was a 72-year-old female with a history of breast and vulvar cancer. The simultaneous occurrence of two synchronous tumours in the pancreas was striking. Due to the presence of PGL and multiple meta- and synchronous tumours, the patient was referred to genetic counselling. Tumour tissue from the vulvar carcinoma, the PDAC and the PGL was analysed by targeted next-generation sequencing (NGS) of 161 cancer-related genes and by whole exome sequencing (WES). Peripheral blood was also examined by NGS and WES. These genetic analyses revealed germline polymorphisms in AXIN2 (NM_004655.4:c 0.2272 G>A; p.Ala758Thr), BRCA2 (NM_000059.3:c.9976 A>T; p.Lys3326Ter), NCOR1 (NM_006311.4:c 0.6544 G>A; p.Ala2182Thr) and SPTA1 (NM_003126.3:c 0.373 G>A; p.Ala125Thr) and somatic mutations of KRAS (NM_033360.3;c 0.35 G>A; p.Gly12Asp) and TP53 (NM_000546.5; c.602delT; p.Leu201CysfsTer46) in the PDAC and of TP53 (NM_000546.5; c 0.733 G>A; p.Gly245Ser) and TERT (NM_198253.2; c.-124 C>T; promotor region) in the vulvar carcinoma. Breast carcinoma tissue was not available for genetic analysis. The results of the genetic analyses did not explain the presence of multiple tumours in this patient, despite a slightly increased risk of breast cancer associated with the identified BRCA2 polymorphism. To our knowledge, this is the first report of the synchronous occurrence of PDAC and PGL. This case emphasizes the importance of thorough macroscopic examination of pancreatic resection specimens, as coexisting neoplasms may otherwise be missed.

Long-term outcome after EUS-guided radiofrequency ablation: Prospective results in pancreatic neuroendocrine tumors and pancreatic cystic neoplasms

Background and study aims  Endoscopic ultrasound-guided radiofrequency ablation (EUS-RFA) for pancreatic neuroendocrine tumors (NETs) and intraductal pancreatic mucinous neoplasia (IPMN) with worrisome features or high-risk stigmata (WF/HRS) has been evaluated in few series with short-term outcomes. This study's primary endpoint was to assess the long-term efficacy of EUS-RFA in patients with NETs or pancreatic cystic neoplasms (PCNs) over at least 3 years. Patients and methods  Twelve patients had 14 NETs with a mean 13.4-mm size (10-20) and 17 patients had a cystic tumor (16 IPMN, 1 MCA) with a 29.1-mm mean size (9-60 were included. They were treated with EUS-guided RFA, evaluated prospectively at 1 year, and followed annually for at least 3 years. Results  The mean duration of follow-up was 42.9 months (36-53). Four patients died during follow-up (17-42 months) from unrelated diseases. At 1-year follow-up, and 85.7 % complete disappearance was seen in 12 patients with 14 NETs. At the end of follow-up (45.6 months), complete disappearance of tumors was seen in 85.7 % of cases. One case of late liver metastasis occurred in a patient with initial failure of EUS-RFA. At 1-year follow-up, a significant response was seen in 70.5 % of 15 patients with PCNs. At the end of the follow-up, there was a significant response in 66.6 % with no mural nodules. Two cases of distant pancreatic adenocarcinoma unrelated to IPMN occurred. Conclusions  EUS-RFA results for pancreatic NETs or PCNs appear to be stable during 42 months of follow-up.

Intraductal Papillary Mucinous Carcinoma Versus Conventional Pancreatic Ductal Adenocarcinoma: A Comprehensive Review of Clinical-Pathological Features, Outcomes, and Molecular Insights

Intraductal papillary mucinous neoplasms (IPMN) are common and one of the main precursor lesions of pancreatic ductal adenocarcinoma (PDAC). PDAC derived from an IPMN is called intraductal papillary mucinous carcinoma (IPMC) and defines a subgroup of patients with ill-defined specificities. As compared to conventional PDAC, IPMCs have been associated to clinical particularities and favorable pathological features, as well as debated outcomes. However, IPMNs and IPMCs include distinct subtypes of precursor (gastric, pancreato-biliary, intestinal) and invasive (tubular, colloid) lesions, also associated to specific characteristics. Notably, consistent data have shown intestinal IPMNs and associated colloid carcinomas, defining the “intestinal pathway”, to be associated with less aggressive features. Genomic specificities have also been uncovered, such as mutations of the GNAS gene, and recent data provide more insights into the mechanisms involved in IPMCs carcinogenesis. This review synthetizes available data on clinical-pathological features and outcomes associated with IPMCs and their subtypes. We also describe known genomic hallmarks of these lesions and summarize the latest data about molecular processes involved in IPMNs initiation and progression to IPMCs. Finally, potential implications for clinical practice and future research strategies are discussed.

Automated Detection of Pancreatic Cystic Lesions on CT Using Deep Learning

Pancreatic cystic lesions (PCL) are a frequent and underreported incidental finding on CT scans and can transform into neoplasms with devastating consequences. We developed and evaluated an algorithm based on a two-step nnU-Net architecture for automated detection of PCL on CTs. A total of 543 cysts on 221 abdominal CTs were manually segmented in 3D by a radiology resident in consensus with a board-certified radiologist specialized in abdominal radiology. This information was used to train a two-step nnU-Net for detection with the performance assessed depending on lesions' volume and location in comparison to three human readers of varying experience. Mean sensitivity was 78.8 ± 0.1%. The sensitivity was highest for large lesions with 87.8% for cysts ≥220 mm³ and for lesions in the distal pancreas with up to 96.2%. The number of false-positive detections for cysts ≥220 mm³ was 0.1 per case. The algorithm's performance was comparable to human readers. To conclude, automated detection of PCL on CTs is feasible. The proposed model could serve radiologists as a second reading tool. All imaging data and code used in this study are freely available online.

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

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

CT-Based Radiomics Analysis to Predict Malignancy in Patients with Intraductal Papillary Mucinous Neoplasm (IPMN) of the Pancreas

To assess the performance of CT-based radiomics analysis in differentiating benign from malignant intraductal papillary mucinous neoplasms of the pancreas (IPMN), preoperative scans of 408 resected patients with IPMN were retrospectively analyzed. IPMNs were classified as benign (low-grade dysplasia, n = 181), or malignant (high grade, n = 128, and invasive, n = 99). Clinicobiological data were reported. Patients were divided into a training cohort (TC) of 296 patients and an external validation cohort (EVC) of 112 patients. After semi-automatic tumor segmentation, PyRadiomics was used to extract radiomics features. A multivariate model was developed using a logistic regression approach. In the training cohort, 85/107 radiomics features were significantly different between patients with benign and malignant IPMNs. Unsupervised clustering analysis revealed four distinct clusters of patients with similar radiomics features patterns with malignancy as the most significant association. The multivariate model differentiated benign from malignant tumors in TC with an area under the ROC curve (AUC) of 0.84, sensitivity (Se) of 0.82, specificity (Spe) of 0.74, and in EVC with an AUC of 0.71, Se of 0.69, Spe of 0.57. This large study confirms the high diagnostic performance of preoperative CT-based radiomics analysis to differentiate between benign from malignant IPMNs.

Risk of malignancy in small pancreatic cysts decreases over time

BACKGROUND

Pancreatic cysts <15 mm without worrisome features have practically no risk of malignancy at the time of diagnosis but this can change over time. Optimal duration of follow-up is a matter of debate. We evaluated predictors of malignancy and attempted to identify a time to safely discontinue surveillance.

METHODS

Bi-centric study utilizing prospectively collected databases of patients with pancreatic cysts measuring <15 mm and without worrisome features who underwent surveillance at the Massachusetts General Hospital (1988-2017) and at the University of Verona Hospital Trust (2000-2016). The risk of malignant transformation was assessed using the Kaplan-Meier method and parametric survival models, and predictors of malignancy were evaluated using Cox regression.

RESULTS

806 patients were identified. Median follow-up was 58 months (6-347). Over time, 58 (7.2%) cysts were resected and of those, 11 had high grade dysplasia (HGD) or invasive cancer. Three additional patients had unresectable cancer for a total rate of malignancy of 1.7%. Predictors of development of malignancy included an increase in size ≥2.5 mm/year (HR = 29.54, 95% CI: 9.39-92.91, P < 0.001) and the development of worrisome features (HR = 9.17, 95% CI: 2.99-28.10, P = 0.001). Comparison of parametric survival models suggested that the risk of malignancy decreased after three years of surveillance and was lower than 0.2% after five years.

CONCLUSIONS

Pancreatic cysts <15  mm at the time of diagnosis have a very low risk of malignant transformation. Our findings indicate the risk decreases over time. Size increase of ≥2.5 mm/year is the strongest predictor of malignancy.

ACR Appropriateness Criteria® Pancreatic Cyst

Incidental pancreatic cysts are increasingly detected on imaging studies performed for unrelated indications and may be incompletely characterized on these studies. Adequate morphological characterization is critical due to the small risk of malignant degeneration associated with neoplastic pancreatic cysts, as well as the risk of associated pancreatic adenocarcinoma. For all pancreatic cysts, both size and morphology determine management. Specifically, imaging detection of features, such as pancreatic ductal communication and presence or absence of worrisome features or high-risk stigmata, have important management implications. The recommendations in this publication determine the appropriate initial imaging study to further evaluate a pancreatic cyst that was incidentally detected on a nondedicated imaging study. The recommendations are designed to maximize the yield of diagnostic information in order to better risk-stratify pancreatic cysts and assist in guiding future management. The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision include an extensive analysis of current medical literature from peer reviewed journals and the application of well-established methodologies (RAND/UCLA Appropriateness Method and Grading of Recommendations Assessment, Development, and Evaluation or GRADE) to rate the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where evidence is lacking or equivocal, expert opinion may supplement the available evidence to recommend imaging or treatment.

Intraductal papillary mucinous carcinoma versus pancreatic ductal adenocarcinoma: A systematic review and meta-analysis

BACKGROUND

Previous studies have indicated that there may be a difference in tumor biology between intraductal papillary mucinous carcinoma (IPMC) and pancreatic ductal adenocarcinoma (PDAC). However, the data are still controversial. The aim of this systematic review and meta-analysis was to summarize and compare the outcome of IPMC and PDAC after surgical resection.

METHODS

Studies comparing IPMC and PDAC were identified using Medline and Embase search engines. Primary outcomes of interest were survival and recurrence. Secondary outcomes were clinicopathological characteristics. Meta-analysis of data was conducted using a random-effects model.

RESULTS

A total of 14 studies were included. Pooled analysis revealed an improved 5-year overall survival (OS) for IPMC compared to PDAC (OR 0.23, 95% CI 0.09-0.56). Both colloid and tubular IPMC showed improved 5-year OS compared to PDAC (OR 0.12, 95% CI 0.05-0.25 and OR 0.38, 95% CI 0.26-0.54, respectively). Median survival time ranged from 21 to 58 months in the IPMC group compared to 12-23 months in the PDAC group. No meta-analysis could be performed on recurrence or on time-to-event data. Descriptive data showed no survival difference for higher TNM stages. IPMC was more often found at a TNM-stage of 1 (OR 4.40, 95% CI 2.71-7.15) and had lower rates of lymph node spread (OR 0.43, 95% CI 0.32-0.57).

CONCLUSION

Available data suggest that IPMC has a more indolent course with a better 5-year OS compared to PDAC. The histopathological features are less aggressive in IPMC. The reason may be earlier detection. However, for IPMC with higher TNM stages the survival seems to be similar to that of PDAC.

Diffusion-weighted image improves detectability of magnetic resonance cholangiopancreatography for pancreatic ductal adenocarcinoma concomitant with intraductal papillary mucinous neoplasm

The present study is aimed to clarify the utility of magnetic resonance cholangiopancreatography (MRCP) and the additional value of diffusion-weighted imaging (DWI) in diagnosing pancreatic ductal adenocarcinoma (PDAC) concomitant with intraductal papillary mucinous neoplasm (IPMN).This retrospective study involved 38 patients with PDAC concomitant with IPMN and 114 patients (control) who were randomly selected from 320 patients with IPMN without PDAC and were matched with cases for magnetic resonance imaging (MRI) strength (1.5 T/3.0 T). Two radiologists reviewed the 2 MR image sets with relevant clinical information blinded, first MRCP alone and then combined MRI set including DWI. Diagnostic capability and interobserver agreement were assessed by using receiver operating characteristics curve (Az) analysis and weighted κ statistics.Az values for the 2 observers were 0.834 and 0.821 for MRCP alone and 0.964 and 0.926 for the combined MRI (P < .001 and P < .001), respectively. The sensitivity of MRCP alone was 61% (23/38), with both observers failing to diagnose PDACs located at the end of tail or away from the pancreatic duct. Meanwhile, with combined MRI, sensitivity was significantly increased for both observers (61% to 92%, P = .002; 61% to 87%, P = .004). Moreover, the interobserver agreement was higher with combined MRI (κ = 0.85) than MRCP alone (κ = 0.59).MRCP and DWI might be a superior option with a higher diagnostic capability of PDAC concomitant with IPMN than MRCP alone, especially for tumors away from the pancreatic duct.

Intraductal Papillary Mucinous Neoplasms of The Pancreas: A Nationwide Registry-Based Study

BACKGROUND AND AIMS:

To investigate the paraclinical and pathological features of surgically resected intraductal papillary mucinous neoplasms in Sweden.

MATERIALS AND METHODS:

A review of prospectively collected data on patients undergoing pancreatic resection for a histopathologically verified intraductal papillary mucinous neoplasm between 2010 and 2016 was performed using the Swedish National Registry for Pancreatic and Periampullary Cancer.

RESULTS:

A total of 3038 pancreatic resections were performed during the study period, of which 251 (8.3%) were due to intraductal papillary mucinous neoplasms. The intraductal papillary mucinous neoplasm cases comprised 227 noninvasive and 24 invasive lesions. There was an annual increase in the number of resected intraductal papillary mucinous neoplasms, from 13 in 2010 to 56 in 2016, and an increase in the proportion of intraductal papillary mucinous neoplasm to the total number of pancreatic resections (4.7%-11%). Biliary obstruction was the only independent predictor of invasive disease, with odds ratio 3.106 (p = 0.030). There was no difference in survival between low-, intermediate-, and high-grade dysplastic lesions (p = 0.417). However, once invasive, the prognosis was severely impacted (p < 0.001). Three-year survival was 90% for noninvasive intraductal papillary mucinous neoplasm and 39% for invasive intraductal papillary mucinous neoplasm. Survival was better in lymph node negative invasive intraductal papillary mucinous neoplasm (p = 0.021), but still dismal compared to noninvasive lesions (p < 0.001).

CONCLUSION:

The number of surgically resected intraductal papillary mucinous neoplasms is increasing in Sweden. Biliary obstruction is associated with invasive disease. Low-to-high-grade dysplastic intraductal papillary mucinous neoplasm has an excellent prognosis, while invasive intraductal papillary mucinous neoplasm has a poor survival rate.

Intraductal papillary mucinous neoplasms of the pancreas: a clinical challenge

The incidental detection rate of intraductal papillary mucinous neoplasms (IPMNs) has significantly increased. However, little is known about the natural history of these tumors. Their optimal management and appropriate follow-up are still unclear. We have, therefore, reviewed the available literature on IPMN focusing on their diagnosis, treatment according to the risk of malignant transformation, and follow-up. Areas covered: Bibliographical searches were performed in PubMed for the terms 'intraductal papillary mucinous neoplasm' and 'natural history' and 'diagnosis' and 'treatment' and 'surgery' and 'follow-up' and 'prognosis.' PubMed was used to search for all the relevant articles published over the last 10 years. A total of 7244 records were identified. After filtering for year range, English language, human studies, article types, and removing duplicates, 74 articles were left with the strongest level of evidence. Expert commentary: Available guidelines for IPMN management are mainly based on expert opinions and may lack strong evidence. Further studies are warranted to better predict the risk of recurrence/future malignancy and to establish standardized guidelines. IPMNs management should be based on multidisciplinary discussion and treatment should be tailored to an individual patient according to patient and tumor characteristics.

Pancreatic Fat Content Detected by Computed Tomography and Its Significant Relationship With Intraductal Papillary Mucinous Neoplasm

OBJECTIVES

Intraductal papillary mucinous neoplasms (IPMNs) are premalignant lesions of pancreatic ductal adenocarcinomas (PDACs). Fat accumulation in the pancreas is increasingly recognized as a cause of PDAC. We aimed to identify factors that are relevant between IPMN and metabolic-related factors, including pancreatic fat.

METHODS

The database for 781 subjects who underwent a health checkup and upper abdominal magnetic resonance imaging was searched and computed tomography attenuation indexes (pancreatic and spleen attenuation, pancreas-to-spleen attenuation ratio) were decided by measuring the regions of interest in the pancreas and spleen on nonenhanced images, using Hounsfield units. Eighty-five subjects from each of the IPMN and noncyst groups were matched for age, sex, and glycemic status and statistically compared in clinical characteristics.

RESULTS

There was no difference in metabolic-related factors except for apolipoprotein A1 and high-density lipoprotein cholesterol between the 2 groups in univariate analysis. Multivariate logistic regression analysis showed that both indexes were significantly associated with IPMN (odds ratio, 0.905 [95% confidence intervals, 0.851-0.963; P = 0.002]; odds ratio, 0.006 [95% confidence intervals, 0.000-0.152; P = 0.002]).

CONCLUSIONS

Pancreatic fat content measured by computed tomography was significantly associated with IPMN. These results suggest that IPMN may develop secondary to pancreatic steatosis that could be an overlapping risk factor for PDAC and IPMN.

The 2012 International Consensus Guidelines of Intraductal Papillary Mucinous Neoplasms of the Pancreas (Fukuoka Criteria) Predict the Malignant Potential, Even in Actual Clinical Situations

OBJECTIVES

The aim of the present study was to validate the use of the 2012 International Consensus Guidelines for intraductal papillary mucinous neoplasm (IPMN) (Fukuoka criteria) in patients without findings of obstructive jaundice and/or an enhanced solid component.

METHODS

This retrospective study included patients who underwent pancreatectomy for IPMN between October 2002 and September 2016. The sensitivity, specificity, and positive and negative predictive values for malignancy were calculated for each feature of high-risk stigmata.

RESULTS

Of the 135 patients who underwent surgery for IPMN, 50 (37.0%) had low/intermediate-grade dysplasia, 25 (18.5%) had high-grade dysplasia, and the remaining 60 (44.5%) had invasive carcinoma. A malignant potential was, thus, present in 63% of all resected cases. Considering an actual clinical situation, the predictors for malignant potential were assessed in 62 patients without findings of obstructive jaundice and/or an enhanced solid component. A multivariate analysis revealed that the Fukuoka criteria were the only independent factor for predicting the malignant potential (odds ratio, 5.69; P = 0.036).

CONCLUSIONS

The present study suggested that malignant potential can be accurately detected by faithfully keeping to the Fukuoka criteria. Using these criteria enables us to identify patients with malignant potential, even in the actual clinical situations.

Pancreatic Neuroendocrine Tumors and Intraductal Papillary Mucinous Neoplasm of the Pancreas: A Systematic Review

OBJECTIVES

This study aimed to identify factors that explain the association of intraductal papillary mucinous neoplasms-pancreatic neuroendocrine tumors (IPMNs-PNETs), radiological characteristics, and factors that might guide therapy.

METHODS

We performed a systematic review of the literature to search for articles on concurrent IPMN-PNET, mixed endocrine-exocrine pancreatic tumors, and/or PNET with an intraductal growth pattern.

RESULTS

A review of the literature suggests that there is some confusion about association of IPMNs-PNETs. Regarding this association, the studies collected data from 32 patients. Eleven patients presented concurrent tumors, 9 mixed endocrine-exocrine tumors, and no data were available in the remaining 7. In addition, the relationship IPMN-PNET focuses not only on the coexistence of the 2 lesions, but also on the possibility of the intraductal growth of the endocrine lesion. In the literature, in 4 cases, the preoperative radiological diagnosis had been IPMN.

CONCLUSIONS

Intraductal papillary mucinous neoplasms and PNETs may be associated in a number of scenarios. The association may be due to the concurrent existence of independent lesions, may be a mixed endocrine-exocrine tumor, or may be due to intraductal growth of the endocrine lesion. But the literature is confusing. It is not known whether the association is accidental or whether there is an etiological reason. Further studies are needed to investigate this scenario.

Long-term Risk of Pancreatic Malignancy in Patients With Branch Duct Intraductal Papillary Mucinous Neoplasm in a Referral Center

BACKGROUND & AIMS

Little is known about the development of branch duct intraductal papillary mucinous neoplasms (BD-IPMNs). We evaluated long-term outcomes of a large cohort of patients with BD-IPMNs to determine risk of malignancy and define a subset of low-risk BD-IPMNs.

METHODS

We performed a retrospective analysis of data from 577 patients with suspected or presumed BD-IPMN under surveillance at the Massachusetts General Hospital. Patients underwent cross-sectional imaging analysis at 3 months or later after their initial diagnosis. The diagnosis of BD-IPMN was based on the presence of unilocular or multilocular cysts of the pancreas and a non-dilated main pancreatic duct (<5 mm). We collected demographic, clinical, and pathology data. Cysts were characterized at the time of diagnosis and during the follow-up period. Follow-up duration was time between initial cyst diagnosis and date of last visit or death for patients without development of pancreatic cancer, date of surgery for patients with histologically confirmed malignancy, or date of first discovery of malignancy by imaging analysis for patients with unresectable tumors or who underwent neoadjuvant treatment before surgery. The primary outcome was risk of malignancy, with a focus on patients followed for 5 years or more, compared with that of the US population, based on standardized incidence ratio.

RESULTS

Of the 577 patients studied, 479 (83%) were asymptomatic at diagnosis and 363 (63%) underwent endoscopic ultrasound at least once. The median follow-up time was 82 months (range, 6-329 months) for the entire study cohort; 363 patients (63%) underwent surveillance for more than 5 years, and 121 (21%) for more than 10 years. Malignancies (high-grade dysplasia or invasive neoplasm) developed after 5 years in 20 of 363 patients (5.5%), and invasive cancer developed in 16 of 363 patients (4.4%). The standardized incidence ratio for patients with BD-IPMNs without worrisome features of malignancy at 5 years was 18.8 (95% confidence interval, 9.7-32.8; P < .001). One hundred and eight patients had cysts ≤1.5 cm for more than 5 years of follow-up; only 1 of these patients (0.9%) developed a distinct ductal adenocarcinoma. By contrast, among the 255 patients with cysts >1.5 cm, 19 (7.5%) developed malignancy (P = .01).

CONCLUSIONS

In a retrospective analysis of patients with BD-IPMNs under surveillance, their overall risk of malignancy, almost 8%, lasted for 10 years or more, supporting continued surveillance after 5 years. Cysts that remain ≤1.5 cm for more than 5 years might be considered low-risk for progression to malignancy.

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.

Pancreatic resection for intraductal papillary mucinous neoplasm- a thirteen-year single center experience

BACKGROUND

The purpose of this study is to review our results for pancreatic resection in patients with intraductal papillary mucinous neoplasm (IPMN) with and without associated carcinoma.

METHODS

A total of 54 patients undergoing pancreatic resection for IPMN in a single university surgical center (Medical University of Graz) were reviewed retrospectively. Their survival rates were compared to those of patients with pancreatic ductal adenocarcinoma.

RESULTS

Twenty-four patients exhibit non-invasive IPMN and thirty patients invasive IPMN with associated carcinoma. The mean age is 67 (+/-11) years, 43 % female. Surgical strategies include classical or pylorus-preserving Whipple procedure (n = 30), distal (n = 13) or total pancreatectomy (n = 11), and additional portal venous resection in three patients (n = 3). Median intensive care stay is three days (range 1 - 87), median in hospital stay is 23 days (range 7 - 87). Thirty-day mortality is 3.7 %. Median follow up is 42 months (range 0 - 127). One-, five- and ten-year overall actuarial survival is 87 %; 84 % and 51 % respectively. Median overall survival is 120 months. Patients with non-invasive IPMN have significantly better survival than patients with invasive IPMN and IPMN-associated carcinoma (p < 0.008). In the subgroup of invasive IPMN with associated carcinoma, a positive nodal state, perineural invasion as well as lymphovascular infiltration are associated with poor outcome (p < 0.0001; <0.0001 and =0.001, respectively). Elevated CA 19-9(>37 U/l) as well as elevated lipase (>60 U/l) serum levels are associated with unfavorable outcome (p = 0.009 and 0.018; respectively). Patients operated for pancreatic ductal adenocarcinoma show significantly shorter long-term survival than patients with IPMN associated carcinoma (p = 0.001).

CONCLUSIONS

Long-term outcome after pancreatic resection for non-invasive IPMN is excellent. Outcome after resection for invasive IPMN with invasive carcinoma is significantly better than for pancreatic ductal adenocarcinoma. In low- and intermediate risk IPMN with no clear indication for immediate surgical resection, a watchful waiting strategy should be evaluated carefully against surgical treatment individually for each patient.

Treatment of branch-duct intraductal papillary mucinous neoplasms of the pancreas: state of the art

The diagnosis of branch-duct intraductal papillary mucinous neoplasms (BD-IPMNs) has been dramatically increased. BD-IPMNs are frequently discovered as incidental findings in asymptomatic individuals, mainly in elderly patients. An accurate evaluation of BD-IPMNs with high-resolution imaging techniques and endoscopic ultrasound is necessary. Patients with high-risk stigmata (HRS, obstructive jaundice, enhanced solid component) should undergo resection. Patients with worrisome features (WF, cyst size ≥3 cm, thickened enhanced cyst walls, non-enhanced mural nodules, and clinical acute pancreatitis) may undergo either a strict surveillance based on patients' characteristics (age, comorbidities) or surgical resection. Non-operative management is indicated for BD-IPMNs without HRS and WF. Patients with BD-IPMN who do not undergo resection may develop malignant change over time as well as IPMN-distinct pancreatic cancer. However, non-operative management of BD-IPMNs lacking WF and HRS is safe and the risk of malignant degeneration seems relatively low. The optimal surveillance protocol is currently unclear.