Pre-operative nomogram predicting malignant potential in the patients with intraductal papillary mucinous neoplasm of the pancreas: focused on imaging features based on revised international guideline

Systematic review on surveillance for non-resected branch-duct intraductal papillary mucinous neoplasms of the pancreas

BACKGROUND

The management of branch-duct type intraductal papillary mucinous neoplasms (BD-IPMN) varies in existing guidelines. This study investigated the optimal surveillance protocol and safe discontinuation of surveillance considering natural history in non-resected IPMN, by systematically reviewing the published literature.

METHODS

This review was guided by PRISMA. Research questions were framed in PICO format "CQ1-1: Is size criteria helpful to determine surveillance period? CQ1-2: How often should surveillance be carried out? CQ1-3: When should surveillance be discontinued? CQ1-4: Is nomogram predicting malignancy useful during surveillance?". PubMed was searched from January-April 2022.

RESULTS

The search generated 2373 citations. After screening, 83 articles were included. Among them, 33 studies were identified for CQ1-1, 19 for CQ1-2, 26 for CQ1-3 and 12 for CQ1-4. Cysts <1.5 or 2 cm without worrisome features (WF) were described as more indolent, and most studies advised an initial period of surveillance. The median growth rate of cysts <2 cm ranged from 0.23 to 0.6 mm/year. Patients with cysts <2 cm showing no morphological changes and no WF after 5-years of surveillance have minimal malignancy risk of 0-2%. Two nomograms created with over 1000 patients had AUCs of around 0.8 and appear to be feasible in a real-world practice.

CONCLUSIONS

For patients with suspected BD-IPMN <2 cm and no other WF, less frequent surveillance is recommended. Surveillance may be discontinued for cysts that remain stable during 5-year surveillance, with consideration of patient condition and life expectancy. With this updated surveillance strategy, patients with non-worrisome BD-IPMN should expect more streamlined management and decreased healthcare utilization.

International evidence-based Kyoto guidelines for the management of intraductal papillary mucinous neoplasm of the pancreas

This study group aimed to revise the 2017 international consensus guidelines for the management of intraductal papillary mucinous neoplasm (IPMN) of the pancreas, and mainly focused on five topics; the revision of high-risk stigmata (HRS) and worrisome features (WF), surveillance of non-resected IPMN, surveillance after resection of IPMN, revision of pathological aspects, and investigation of molecular markers in cyst fluid. A new development from the prior guidelines is that systematic reviews were performed for each one of these topics, and published separately to provide evidence-based recommendations. One of the highlights of these new "evidence-based guidelines" is to propose a new management algorithm, and one major revision is to include into the assessment of HRS and WF the imaging findings from endoscopic ultrasound (EUS) and the results of cytological analysis from EUS-guided fine needle aspiration technique, when this is performed. Another key element of the current guidelines is to clarify whether lifetime surveillance for small IPMNs is required, and recommends two options, "stop surveillance" or "continue surveillance for possible development of concomitant pancreatic ductal adenocarcinoma", for small unchanged BD-IPMN after 5 years surveillance. Several other points are also discussed, including identifying high-risk features for recurrence in patients who underwent resection of non-invasive IPMN with negative surgical margin, summaries of the recent observations in the pathology of IPMN. In addition, the emerging role of cyst fluid markers that can aid in distinguishing IPMN from other pancreatic cysts and identify those IPMNs that harbor high-grade dysplasia or invasive carcinoma is discussed.

Association of high-risk stigmata and worrisome features with advanced neoplasia in intraductal papillary mucinous neoplasms (IPMN): A systematic review

BACKGROUND

This systematic review aimed to assess the diagnostic accuracy of the International Consensus Fukuoka Guidelines (ICG2017) in identifying high-risk lesions of Intraductal Papillary Mucinous Neoplasms (IPMNs).

METHODS

The ICG2017 revision committee conducted a comprehensive literature review to establish evidence-based statements on IPMNs. The review focused on articles examining the diagnostic value of imaging features (e.g., cyst or main pancreatic duct diameter), clinical symptoms associated with IPMN, and serum biomarkers. Five clinical questions regarding high-risk stigmata (HRS) and worrisome features (WF) in the ICG2017 guidelines were addressed.

RESULTS

A total of 210 articles were reviewed. The findings revealed a significant association between the presence of mural nodules ≥5 mm in diameter or solid components with contrast enhancement and the diagnosis of high-grade dysplasia or invasive carcinoma. Contrast-enhanced diagnostic tools, such as CT, MRI, or EUS, demonstrated the highest prediction rate and were recommended. Positive cytology was identified as an HRS, while symptoms like acute pancreatitis and cyst diameter growth ≥2.5 mm per year were considered WFs. The use of nomograms and multiple diagnostic factors was recommended for optimal IPMN management.

CONCLUSIONS

This systematic review provides evidence supporting the improved diagnostic accuracy of ICG2017 in identifying high-risk lesions of IPMN. The multidisciplinary incorporation of HRS and WF based on imaging findings and clinical symptoms is crucial. These findings should inform the revision of ICG2017, enhancing the evaluation and management of IPMN patients. By implementing these recommendations, clinicians can make more informed decisions, leading to better diagnosis and treatment outcomes for high-risk IPMN cases.

Acute pancreatitis in intraductal papillary mucinous neoplasm: a single-center retrospective cohort study with systematic review and meta-analysis

BACKGROUND

Intraductal papillary mucinous neoplasm (IPMN) is a cystic tumor of the pancreas arising from abnormal papillary proliferation of ductal epithelial cells, and is a precancerous lesion of pancreatic malignancy. This study aimed to evaluate associations between acute pancreatitis (AP) and histologic subtypes of IPMN.

METHODS

In the clinical study, patients with IPMN confirmed by surgical resection specimens at our institute between 2009 and 2021 were eligible for inclusion. Associations and predictive accuracy of AP on the presence of HGD were determined by logistic regressions. In addition, a systematic review and meta-analysis was conducted through literatures upon search in PubMed, Embase, CENTRAL, China National Knowledge Infrastructure (CKNI), and Wanfang database, up to June, 2023. Pooled effects of the associations between AP and HGD and intestinal epithelial subtype subtype, shown as odds ratios (ORs) with 95% confidence intervals (CIs), were calculated using random effects model.

RESULTS

The retrospective cohort study included 47 patients (32 males, 15 females) diagnosed with IPMN at our center between 2009 and 2021, including 11 cases with AP (median 62 years) and 36 cases (median 64.5 years) without. Accuracy, sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of AP in predicting HGD were 78.7%, 57.1%, 82.5%, 36.4%, and 91.7%, respectively. Univariate logistic regression analysis showed that AP group had greater odds of presence of HGD (OR: 6.29,95% CI: 1.14-34.57) than non-AP group. Meta-analysis of five case-control studies in the literature included 930 patients and showed that AP-IPMN patients had higher odds for HGD (OR: 2.13, 95% CI 1.38-3.29) and intestinal epithelial subtype (OR: 5.38, 95% CI: 3.50-8.27) compared to non-AP IPMN.

CONCLUSIONS

AP is predictive of malignancy in patients with IPMN.

Prediction of malignant intraductal papillary mucinous neoplasm: A nomogram based on clinical information and radiological outcomes

OBJECTIVE

Clinical practitioners face a significant challenge in maintaining a healthy balance between overtreatment and missed diagnosis in the management of intraductal papillary mucinous neoplasm (IPMN). The current study aimed to identify significant risk factors of malignant IPMN from a series of clinical and radiological parameters that are widely available and noninvasive and develop a method to individually predict the risk of malignant IPMN to improve its management.

METHODS

We retrospectively investigated 168 patients who were pathologically diagnosed with IPMN after individualized pancreatic resection between June, 2012 and December, 2020. Independent predictors determined using both univariate and multivariate analyses to construct a predictive model. The discriminatory power of the nomogram was assessed using the area under the receiver operating characteristic curve (AUC). Decision curve analysis was performed to demonstrate the clinical usefulness of the nomogram. Internal cross validation was performed to assess the validity of the predictive model.

RESULTS

In the multivariate analysis, five significant independent risk factors were identified: increased serum CA19-9 level, low prognostic nutritional index (PNI), cyst size, enhancing mural nodule, and main pancreatic duct diameter. The nomogram based on the parameters mentioned above had outstanding performance in distinguishing malignancy, with an AUC of 0.907 (95% confidence interval: 0.859-0.956, p < 0.05), which remained 0.875 after internal cross-validation, and showed good clinical usefulness.

CONCLUSION

A novel nomogram for predicting malignant IPMN first introducing PNI was developed, which may aid in improving IPMN management. Nevertheless, external validation is required to confirm its efficacy.

Intracystic papillary neoplasm diagnosis following an extended cholecystectomy: a case report … and literature review

We report a case of intracystic papillary neoplasms (ICPN) that was difficult to differentiate from adenocarcinoma of the gallbladder. A 64-year-old man visited our hospital for an examination of gallbladder tumors. At the preoperative examination, the tumor was revealed a papillary type of tumor in the body of the gallbladder without the findings that without the findings that suggested the tumor invasion into the deep subserosal layer. The patient underwent an extended cholecystectomy. Papillary lesions were observed mainly in the body of the gallbladder, with flattened elevated lesions at the gallbladder fundus. Within each of these tumors, cells corresponding to intraepithelial adenocarcinoma were irregularly interspersed, leading to a diagnosis of ICPN. The patient is currently undergoing follow-up with no recurrence postoperatively. The prognosis of ICPN is generally good; however, preoperative diagnosis remains challenging. Therefore, a treatment plan for gallbladder cancer should be applied.

Natural history of intracholecystic papillary neoplasm (ICPN): a rare case of ICPN whose natural history was closely followed by ultrasound

The natural history of intracholecystic papillary neoplasm (ICPN), especially the speed of growth from small benign to a carcinomatous lesion, is quite unrevealed. Here, we report an extremely rare case of ICPN, in which the papillary lesion was observed transforming from small and benign to malignant using abdominal ultrasound (AUS) over 2 years during routine health checks. A 44-year-old man underwent a routine health check-up. The initial AUS showed a small sessile polyp in the gallbladder, which enlarged slightly at the next AUS, a year later. In the third year, the polypoid lesion enlarged markedly, with a maximum diameter of 10 × 9 × 7 mm. Therefore, a laparoscopic cholecystectomy was performed. Microscopically, the 10 mm tumor had intracytoplasmic mucus, and a clear cytoplasm compatible with gastric-type features. Immunohistochemical analysis showed positive staining of atypical cells for MUC6 and PAS. These findings led to the diagnosis of ICPN with high-grade intraepithelial neoplasia of the gastric type. In conclusion, sessile polyps with rapid growth might be a crucial finding in the early stage of ICPN.

MRI-Based Pancreatic Atrophy Is Associated With Malignancy or Invasive Carcinoma in Intraductal Papillary Mucinous Neoplasm

Background

Abrupt change in the caliber of the main pancreatic duct (MPD) with distal pancreatic atrophy (PA) was considered as one of worrisome features in the International Association of Pancreatology guideline and American College of Gastroenterology guideline for the management of intraductal papillary mucinous neoplasms (IPMNs). However, this feature was not included in other guidelines. Moreover, the association between PA alone and malignancy in IPMNs has not been fully evaluated. In the present study, we investigated the role of image-based PA in identifying malignant IPMNs or invasive carcinoma.

Methods

A total of 186 patients with IPMNs were included for analysis. The tumor size, location, MPD diameter, presence of a mural nodule (MN), and PA were evaluated using magnetic resonance imaging. Demographic information and serum carbohydrate antigen 19-9 and carcinoembryonic antigen (CEA) levels were also collected. IPMNs with high-grade dysplasia and associated invasive carcinoma were regarded as malignant IPMNs.

Results

PA was observed in 34 cases (18.3%). The occurrence of malignant IPMNs or invasive carcinoma in patients with PA were significantly higher than in those without PA (52.9% vs. 22.3%; 44.1% vs. 8.9%, all P < 0.01). Multivariate logistic regression analysis showed that PA was an independently associated factor for malignant IPMNs [odds ratio (OR) = 2.69, 95% confidence interval (CI): 1.07-6.78] or invasive carcinoma (OR = 7.78, 95%CI: 2.62-23.10) after modified with confounders. Subgroup analysis in MPD-involved IPMNs also indicated that PA was an independently associated factor for invasive carcinoma (OR = 9.72, 95%CI: 2.43-38.88). PA had a similar performance with MPD plus MN [the area under the curve (AUC) was both 0.71] in identifying malignancy. PA had a higher performance in identifying invasive carcinoma in MPD-involved IPMNs than MN (AUC = 0.71 vs. 0.65, P = 0.02).

Conclusion

Our data showed that imaging-based PA was associated with malignancy or invasive carcinoma regardless of abrupt change in the caliber of MPD in IPMNs. PA had an acceptable performance in identifying malignant IPMNs.

Magnetic resonance imaging-derived fat fraction predicts risk of malignancy in intraductal papillary mucinous neoplasm

PURPOSE

Assess the relationship between MRI-derived pancreatic fat fraction and risk of malignancy in intraductal papillary mucinous neoplasm (IPMN).

METHODS

MRIs of patients with IPMN who underwent pancreaticoduodenectomy were analyzed. IPMN with low-grade dysplasia (n = 29) were categorized as low-risk while IPMN at high risk of malignancy consisted of those with high-grade dysplasia/invasive carcinoma (n = 33). Pancreatic fat-fraction (FFmean) was measured using the 2-point Dixon-method. Images were evaluated for the high-risk stigmata and worrisome features according to the revised 2017 Fukuoka consensus criteria. Data on serum CA19-9, Diabetes Mellitus (DM) status, body mass index (BMI), and histological chronic pancreatitis were obtained.

RESULTS

A significant difference in FFmean was found between the high-risk IPMN (11.45%) and low-risk IPMN (9.95%) groups (p = 0.027). Serum CA19-9 level (p = 0.021), presence of cyst wall enhancement (p = 0.029), and solid mass (p = 0.008) were significantly associated with high-risk IPMN. There was a significant correlation between FFmean and mural nodule size (r = 0.36, p ˂ 0.01), type 2 DM (r = 0.34, p ˂ 0.01), age (r = 0.31, p ˂ 0.05), serum CA 19-9 (r = 0.30, p ˂ 0.05), cyst diameter (r = 0.30, p ˂ 0.05), and main pancreatic duct diameter (r = 0.26, p ˂ 0.05). Regression analysis revealed FFmean (OR 1.103, p = 0.035) as an independent predictive variable of high-risk IPMN.

CONCLUSION

FFmean is significantly associated with high-risk IPMN and an independent predictor of IPMN malignant risk. FFmean may have clinical utility as a biomarker to complement the current IPMN treatment algorithm and improve clinical decision making regarding the need for surgical resection or surveillance.

Ductal Dilatation of ≥5 mm in Intraductal Papillary Mucinous Neoplasm Should Trigger the Consideration for Pancreatectomy: A Meta-Analysis and Systematic Review of Resected Cases

Simple Summary

Intraductal papillary mucinous neoplasms (IPMN) are common but difficult to manage since accurate tools for diagnosing malignancy are unavailable. This study evaluates the diagnostic value of main pancreatic duct (MPD) diameter for detecting IPMN malignancy, using a meta-analysis of published data. The result suggests that malignancy is highly prevalent in IPMN with ductal dilatation of >5 mm.

Abstract

Intraductal papillary mucinous neoplasms (IPMN) are common but difficult to manage since accurate tools for diagnosing malignancy are unavailable. This study tests the diagnostic value of the main pancreatic duct (MPD) diameter for detecting IPMN malignancy using a meta-analysis of published data of resected IPMNs. Collected from a comprehensive literature search, the articles included in this analysis must report malignancy cases (high-grade dysplasia (HGD) and invasive carcinoma (IC)) and MPD diameter so that two MPD cut-offs could be created. The sensitivity, specificity, and odds ratios of the two cutoffs for predicting malignancy were calculated. A review of 1493 articles yielded 20 retrospective studies with 3982 resected cases. A cutoff of ≥5 mm is more sensitive than the ≥10 mm cutoff and has pooled sensitivity of 72.20% and 75.60% for classification of HGD and IC, respectively. Both MPD cutoffs of ≥5 mm and ≥10 mm were associated with malignancy (OR = 4.36 (95% CI: 2.82, 6.75) vs. OR = 3.18 (95% CI: 2.25, 4.49), respectively). The odds of HGD and IC for patients with MPD ≥5 mm were 5.66 (95% CI: 3.02, 10.62) and 7.40 (95% CI: 4.95, 11.06), respectively. OR of HGD and IC for MPD ≥10 mm cutoff were 4.36 (95% CI: 3.20, 5.93) and 4.75 (95% CI: 2.39, 9.45), respectively. IPMN with MPD of >5 mm could very likely be malignant. In selected IPMN patients, pancreatectomy should be considered when MPD is >5 mm.

Abbreviated Magnetic Resonance Imaging With Breath-Hold Three-Dimensional Magnetic Resonance Cholangiopancreatography: Assessment of Malignant Risk of Pancreatic Intraductal Papillary Mucinous Neoplasm

BACKGROUND

For surveillance of pancreatic intraductal papillary mucinous neoplasms (IPMNs), magnetic resonance imaging (MRI)/magnetic resonance cholangiopancreatography (MRCP) is preferred over computed tomography, but the long acquisition time limits its use.

PURPOSE

To investigate the diagnostic performance of abbreviated MRI with breath-hold (BH) three-dimensional MRCP (abbreviated MRI-BH) for malignant risk assessment of pancreatic IPMN.

STUDY TYPE

Retrospective.

POPULATION

Two hundred and thirty-five patients with IPMNs (M:F = 115:120; mean age ± SD, 66 ± 9 years; typical imaging features with ≥2-year stability [N = 172] and histopathologically confirmed [N = 63]).

FIELD STRENGTH/SEQUENCE

3.0 T/ abbreviated MRI-BH (single-shot fast spin-echo, T1W fat-suppressed gradient-echo sequence, and BH-3D-MRCP).

ASSESSMENT

Abbreviated MRI-BH was reviewed by three reviewers, and its diagnostic performance was assessed using the predetermined scoring system. The diagnostic performance for the mural nodule detection was assessed. Additionally, diagnostic performance of abbreviated MRI was compared with that of full-sequence MRI.

STATISTICAL TESTS

Area under the receiver operating characteristic curve (AUC) with z-test, and linear-weighted kappa values.

RESULTS

Thirty-five patients had malignant IPMN. At a cut-off score ≥3, AUCs of abbreviated MRI-BH for detecting malignant IPMN were 0.959 for reviewer 1, 0.962 for reviewer 2, and 0.956 for reviewer 3. The sensitivity of reviewers 1, 2, and 3 was 97.1% for all, and the specificity was 85.5%, 86.0%, and 85.0%, respectively. Regarding mural nodule detection (N = 22), abbreviated MRI-BH demonstrated a sensitivity of 95.5% and a specificity of 88.3% for reviewer 1, a sensitivity of 86.4% and a specificity of 92.0% for reviewer 2, and a sensitivity of 86.4% and a specificity of 89.2% for reviewer 3. There were no significant differences between AUC of abbreviated MRI-BH and that of full-sequence MRI in the three reviewers (P > 0.05).

DATA CONCLUSION

Abbreviated MRI-BH showed good diagnostic performance for detecting malignant IPMNs by using a predetermined scoring system.

LEVEL OF EVIDENCE

3 TECHNICAL EFFICACY STAGE: 2.