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

Pancreatic cancer precursor lesions - Can immunotherapy prevent progression into pancreatic ductal adenocarcinoma?

Pancreatic ductal adenocarcinoma (PDAC) is one of the deadliest cancers, with a 5-year survival rate of only 12.5 %. Early detection of PDAC or addressing risk factors for PDAC development are ways to improve outcomes. PDAC can arise from precursor lesions, including pancreatic intraepithelial neoplasia (PanIN), intraductal papillary mucinous neoplasm (IPMN), and less frequent, mucinous cystic neoplasm (MCN), and other rare precursor variants. High-risk precursor lesions harbor a substantial chance of evolving into PDAC. Such lesions can often be found in resected PDAC specimens adjacent to the cancer. Unfortunately, recognizing precursor lesions that need to be resected is often tricky, and resections frequently end in major surgical interventions. Thus, better ways to handle precursor lesions are desperately needed. We mapped the immune microenvironments (IMEs) of PanINs, IPMNs, and MCNs on a cellular level using multiplex immunofluorescence and computational imaging technology and compared the findings to PDACs and normal pancreatic tissues. We found distinct and potentially targetable mechanisms of immunosuppression between the two main precursor lesions, PanIN and IMPN. Immunosuppression in IPMNs seems partly mediated by programmed cell death protein 1 ligand (PD-L1) expression on antigen-presenting cells (APCs). By contrast, elevated numbers of regulatory T cells (Tregs) seem to be key players in the immunosuppression of PanINs. Thus, treating high-risk IPMNs with anti-PD-1 and high-risk PanINs with agents targeting Tregs, such as anti-lymphocyte associated protein 4 (anti-CTLA-4) antibodies, could reverse their immunosuppressive state. Reversal of immunosuppression will restore immunosurveillance and eventually prevent progression into PDAC. We also review relevant published and ongoing non-surgical treatment approaches for high-risk IPMNs and PanINs.

Cytology of cystic lesions of the pancreas: Practical insights, pearls, and pitfalls

Pancreatic cyst fluid (PCF) specimens present significant interpretive challenges. Accurate preoperative diagnosis is essential for guiding patient management, as pancreatic cysts vary from benign to pre-malignant and malignant. Appropriate triage differentiates low-risk cysts requiring surveillance from high-risk cysts necessitating surgical resection, the latter of which have increased likelihood of progressing to or harboring invasive carcinoma. Optimal PCF assessment integrates radiological, cytological, biochemical, and molecular findings if available. Key biochemical markers such as carcinoembryonic antigen and glucose can improve the detection of neoplastic mucinous cysts. However, cytology remains the most specific modality for identifying high-risk cysts. Cytomorphologic interpretation is particularly challenging due to the scant cellularity and degenerative changes often present in these specimens. This review provides practical insights to improve the evaluation of pancreatic cysts, emphasizing the importance of a multidisciplinary approach and highlighting diagnostic pearls and common pitfalls to aid in accurate interpretation and optimal patient care.

Clinical impact of epithelial types on postoperative outcomes for intraductal papillary mucinous neoplasms: a multicenter retrospective study

BACKGROUND

Intraductal papillary mucinous neoplasms (IPMNs) are classified into three epithelial types with distinct biological behaviors. However, their effects on the postoperative outcomes remain unclear.

METHODS

This multicenter retrospective study included 556 patients with IPMNs who underwent surgical resection. The epithelial types were categorized into the gastric (n = 323), intestinal (n = 160), and pancreatobiliary (n = 73) types. Their associations with the development of extrapancreatic lesions; remnant high-risk lesions (HRLs), including metachronous pancreatic ductal adenocarcinoma (PDAC); and disease-specific survival (DSS) were analyzed.

RESULTS

Fifty-one patients (9.2%) developed extrapancreatic lesions. The 10-year cumulative incidence rates for the gastric, intestinal, and pancreatobiliary types were 9.3%, 9.1%, and 32.0%, respectively (P < 0.001). Multivariate analysis identified invasive carcinoma, the gastric, and pancreatobiliary types as independent predictors. Among 516 patients who did not undergo total pancreatectomy, 40 (7.8%) and 13 (2.5%) developed HRLs and metachronous PDAC, respectively. The 10-year cumulative incidence rates of HRLs and metachronous PDAC for the gastric, intestinal, and pancreatobiliary types were 7.0%, 16.2%, and 37.2% and 1.8%, 3.7%, and 22.7%, respectively (P = 0.001 and P = 0.012). In multivariate analysis, the pancreatobiliary type was an independent predictor of metachronous PDAC. Five-year DSS rates for the gastric, intestinal, and pancreatobiliary types were 92.5%, 96.0%, and 76.1% (P < 0.001), respectively. Multivariate analysis identified invasive carcinoma, the gastric, and pancreatobiliary types as independent prognostic factors for DSS.

CONCLUSIONS

IPMN epithelial type can independently affect postoperative outcomes. In particular, the pancreatobiliary type has significant impact on the development of metachronous PDAC. Therefore, postoperative surveillance should be tailored according to the epithelial type.

Histologic Diagnosis of Pancreatic Cystic Lesions with Endoscopic Ultrasound Fine Needle Biopsy and Impact on Management Decisions

PURPOSE

Endoscopic ultrasound with fine needle biopsy (EUS-FNB) has not been well studied in pancreatic cystic lesions (PCLs). This study evaluates the diagnostic performance of EUS-FNB for PCLs and its impact on management decisions.

METHODS

We conducted a single-center, retrospective study of patients who had EUS-FNB between March 2016 and February 2024. We included patients with ≥ 6-month follow-up and excluded those with a solid pancreatic mass. We obtained clinical, radiologic, endoscopic, surgical, laboratory, and pathology data from chart review. We evaluated: (A) diagnostic yield; (B) predictors of diagnostic FNB; (C) diagnostic accuracy compared to surgical histopathology; (D) appropriateness of management decisions; and (E) adverse events. We compared the appropriateness of management decisions between diagnostic and non-diagnostic FNB.

RESULTS

100 subjects underwent EUS-FNB for PCLs (56% microcystic or with mural nodule). FNB yielded a histologic diagnosis in 60% of sampled lesions. Performing 2 or more needle passes was the only significant predictor of a diagnostic FNB (p = 0.02). Compared to surgical histopathology (n = 21), FNB needles highly accurately diagnosed specific cyst types (IPMN = 85.7%, MCN = 90.5%, SCA = 95.2%, NET = 95.2%, SPN = 100%) and malignant PCLs (accuracy = 81.0%; specificity = 100%; sensitivity = 72.7%). There was a 7.2-fold increase of appropriate management decisions when FNB was diagnostic vs. non-diagnostic (p < 0.001). This was due to improvement in surveillance discontinuation for benign cysts and in appropriate surgical resection for malignant PCLs (p < 0.001). Post-FNB pancreatitis occurred in 4% of patients.

CONCLUSION

EUS-FNB accurately diagnoses different PCL types and their degree of neoplasia, leading to more appropriate management decisions. Future prospective studies are needed to confirm these findings.

Simple cystic lesions of the pancreas: image quality and diagnostic accuracy of photon-counting detector computed tomography

PURPOSE

To evaluate image quality and diagnostic accuracy of photon-counting detector (PCD) CT for the detection of pancreatic cystic lesions (PCLs) compared to energy-integrating detector (EID) CT with MRI serving as reference standard.

MATERIAL AND METHODS

We included consecutive patients who underwent contrast-enhanced PCD-CT of the abdomen and for whom an additional abdominal EID-CT was available. Multiparametric MRI served as the reference standard. CT images were assessed for the presence of PCLs by three radiologists independently in a blinded reading. Image quality, lesion conspicuity, and diagnostic confidence were rated on a 5-point Likert scale (5 = excellent). The coefficient of variation (CV) and the density difference between PCLs and visually normal pancreatic parenchyma were calculated as quantitative imaging measures. Radiation dose was assessed using CTDIvol [mGy].

RESULTS

Among 106 included patients (age 62.7 ± 12.6 years; 45 [42.5%] male), 46 had MRI-confirmed cystic lesions (mean size 8.7 ± 7.4 mm; range 2-45 mm). Diagnostic accuracy for PCLs was significantly higher for PCD-CT vs. EID-CT (area under the curve: 0.81 vs. 0.74; p = 0.002; sensitivity: 76.8% vs. 59.4%). Image quality, lesion conspicuity, and diagnostic confidence were rated superior for PCD-CT vs. EID-CT (all p < 0.001). Quantitative analyses revealed a significantly lower CV (0.19 vs. 0.24; p = 0.002) and a higher density difference (94.1 HU vs. 76.6 HU p < 0.001) between PCLs and visually normal pancreatic parenchyma at lower radiation doses (7.13 vs. 8.68 mGy; p < 0.001) for PCD-CT vs. EID-CT.

CONCLUSION

PCD-CT provided significantly higher diagnostic accuracy and superior image quality for the detection of PCLs compared to conventional EID-CT at lower radiation dose.

Impact of a dilated main pancreatic duct in the expected remnant pancreas on the incidence of clinically significant remnant pancreatic lesion after resection of noninvasive and microinvasive intraductal papillary mucinous neoplasms

BACKGROUND

Partial pancreatectomies for intraductal papillary mucinous neoplasms (IPMN) often leave a dilated main pancreatic duct (MPD). However, its impact on the development of remnant pancreatic lesions is unknown.

METHODS

Medical records of consecutive patients who underwent partial pancreatectomy for noninvasive or microinvasive IPMN with dilated MPD on preoperative imaging between April 2007 and March 2023 at two tertiary referral centers in Japan were retrospectively reviewed. A dilated remnant MPD (DRM) was defined as an MPD diameter of the expected remnant pancreas of ≥5 mm. The clinically significant remnant pancreatic lesion (CSRPL) was defined as a remnant pancreatic lesion which requires intervention.

RESULTS

A total of 172 patients (106 males and 66 females) were analyzed. Preoperatively, 132 patients (76.7 %) had mixed-type IPMN and 40 (23.1 %) had main duct IPMN. Among them, 16 patients (9.3 %) had CSRPL at 1569 days (median; range, 120-5503 days) after the initial surgery. In the preoperative imaging analysis, 104 patients (60.5 %) had DRM. The univariate analysis revealed that high-grade or micro-invasive pathology (p = 0.013) was significantly associated with CSRPL, whereas DRM was inversely associated with CSRPL (p = 0.021). The multivariate analysis revealed that the trends of DRM (p = 0.002) and high-grade/micro-invasive pathology (p = 0.003) remained significant.

CONCLUSIONS

Leaving a dilated MPD did not increase but instead inversely associated with the incidence of CSRPL after IPMN resection. It was suggested that preserving the pancreas, including the dilated MPD, is oncologically safe if the lesion of interest can be resected.

Pancreatic cancer

Pancreatic cancer is frequently a lethal disease with an aggressive tumour biology often presenting with non-specific symptoms. Median survival is approximately 4 months with a 5-year survival of 13%. Surveillance is recommended in individuals with familial pancreatic cancer, specific mutations, and high-risk intraductal papillary mucinous neoplasm, as they are at high risk of developing pancreatic cancer. Chemotherapy combined with surgical resection remains the cornerstone of treatment. However, only a small subset of patients are candidates for surgery. Multi-agent chemotherapy has improved survival in the palliative setting for patients with metastatic disease, as (neo)adjuvant and induction therapy have in patients with borderline resectable and locally advanced pancreatic. Given that pancreatic cancer is predicted to become the second leading cause of cancer-related death by 2030, novel therapies are urgently needed.

Frozen section pathology in IPMN: A systematic review

Intraductal papillary mucinous neoplasms (IPMNs) resection margins are assessed intraoperatively using frozen section (IFS) pathology. We conducted a systematic review to evaluate the concordance of IFS with permanent histopathology and the association between IFS margin status and recurrence. A systematic review was conducted following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. We queried PubMed, Embase, Scopus, and Google Scholar for studies reporting IFS in patients undergoing resection for IPMN. Data, including IFS margin status, recurrence rates, and final pathology, were extracted. Positive margins were defined as high-grade dysplasia or invasive cancer. Seven studies, with a total of 706 patients, met the inclusion criteria. Positive IFS margins were reported in 9.4% of cases, with a high correlation (98%) between IFS and final pathology. Recurrence occurred in 15.4% of patients. Fifty-nine of 85 (69.4%) patients with recurrence of IPMN or intraductal papillary mucinous carcinoma (IPMC) had negative IFS margins. IFS accurately predicts final pathology and is a valuable tool for guiding intraoperative decision-making. A sizeable number of patients experienced recurrence despite negative margins, highlighting the need for adjunct diagnostic modalities and continued surveillance following resection, regardless of margin status.

Surveillance of subcentimeter side-branch intraductal papillary mucinous neoplasms: risk of invasive disease and follow-up recommendations

BACKGROUND

Side-branch intraductal papillary mucinous neoplasms (SB-IPMNs) are increasingly recognized with the increasing use of high-fidelity cross-sectional imaging, particularly subcentimeter (<1 cm) lesions. Data regarding the risk of progression in subcentimeter cysts are absent. This study aimed to define the risk associated with subcentimeter SB-IPMNs and to propose a surveillance strategy based on this cohort.

METHODS

A prospectively maintained database was queried for patients with SB-IPMN who underwent nonoperative surveillance with ≥2 cross-sectional imaging studies performed >6 months apart. Clinically relevant (CR) progression has been previously defined as the development of symptoms, worrisome/high-risk stigmata, or invasive cancer (IC). Growth of ≥5 mm in 2 years is considered CR progression, whereas size of ≥3 cm alone is not.

RESULTS

A total of 1000 patients were included in the study, of whom 291 (29.1%) had SB-IPMN of <1 cm. The median follow-up times from diagnosis were 7.1 years (IQR, 3.2-10.4) in subcentimeter cysts and 6.4 years (IQR, 2.8-10.0) in cysts of ≥1 cm (P =.090). CR progression was less common in the subcentimeter cyst group than in the larger cyst group (7.2% vs 19.0%, respectively; log-rank P <.001). Cysts that progressed did so at similar time intervals (median: 3.7 years in the subcentimeter cyst group vs 3.3 years in the larger cyst group; P =.707). The subcentimeter cyst group developed IC (1.4% in the subcentimeter cyst group vs 1.8% in the larger cyst group; log-rank; P =.608) and high-risk pathology (high-grade dysplasia [HGD]/IC) at a similar rate as the larger cyst group (P =.198). Of 547 patients with cysts that were initially stable for 5 years of surveillance, 25 (4.7%) developed high-risk pathology. This was not different by initial cyst size (log-rank P =.116). Spline curves demonstrated consistently low risk of HGD/IC across increasing cyst size despite a higher rate of CR progression. The CR progression criteria best discriminated high-risk pathology in subcentimeter cysts. The rate of size growth did not correlate with high-risk pathology (hazards ratio, 1.14; 95% CI, 0.88-1.50).

CONCLUSION

Subcentimeter SB-IPMNs develop malignant potential as frequently as their larger counterparts and do so at similar time courses. Often incidental, subcentimeter-presumed SB-IPMNs are diagnosed at arbitrary points in the disease course and require similar surveillance duration as their larger counterparts. The rate of growth is not predictive of high-risk pathology. These cysts do not develop CR progression as frequently. However, such features better discriminate high-risk pathology in subcentimeter cysts, making the development of such features more concerning when they occur.

Endoscopic ultrasound-guided tissue sampling: European Society of Gastrointestinal Endoscopy (ESGE) Technical and Technology Review

This Technical and Technology Review from the European Society of Gastrointestinal Endoscopy (ESGE) represents an update of the previous document on the technical aspects of endoscopic ultrasound (EUS)-guided sampling in gastroenterology, including the available types of needle, technical aspects of tissue sampling, new devices, and specimen handling and processing. Among the most important new recommendations are:ESGE recommends end-cutting fine-needle biopsy (FNB) needles over reverse-bevel FNB or fine-needle aspiration (FNA) needles for tissue sampling of solid pancreatic lesions; FNA may still have a role when rapid on-site evaluation (ROSE) is available.ESGE recommends EUS-FNB or mucosal incision-assisted biopsy (MIAB) equally for tissue sampling of subepithelial lesions ≥20 mm in size. MIAB could represent the first choice for smaller lesions (<20 mm) if proper expertise is available.ESGE does not recommend the use of antibiotic prophylaxis before EUS-guided tissue sampling of solid masses and EUS-FNA of pancreatic cystic lesions.

Current status of endoscopic ultrasound in the diagnosis of intraductal papillary mucinous neoplasms

The new Kyoto guidelines for the management of intraductal papillary mucinous neoplasm (IPMN) provide evidence-based recommendations for the diagnosis and treatment of IPMN. Endoscopic ultrasonography (EUS) is a diagnostic modality with a high spatial resolution that allows detailed observation and obtaining cyst fluid or tissue samples via EUS-guided fine needle aspiration (EUS-FNA). Currently, EUS is an indispensable examination method for the diagnosis of pancreatic diseases. On the other hand, there have been concerns that EUS imaging tends to be highly operator-dependent, and may lack objectivity. Previous guidelines have assigned EUS as an option for patients with worrisome features. However, recent reports indicate that the sensitivity of EUS for the diagnosis of mural nodules (MNs) is more than 90%, comparable or superior to that of contrast-enhanced computed tomography or magnetic resonance cholangiopancreatography. The specific advantages of EUS in the diagnosis of IPMN are: (1) high spatial resolution imaging for the diagnosis of MNs, (2) contrast-enhanced EUS for differentiation of intra-cystic MNs from mucous clots, and (3) pathological diagnosis using EUS-FNA and differential diagnosis of a pancreatic cystic tumor by cystic fluid analysis. In order to utilize EUS in the diagnosis of IPMN, endoscopists are required to have the skills to provide sufficiently objective imaging findings.

Comparison of sedation with pentazocine or pethidine hydrochloride for endoscopic ultrasonography in outpatients: A single-center retrospective study

Objectives

Endoscopic ultrasonography (EUS) plays an important role in the diagnosis of pancreatobiliary diseases. However, an appropriate sedation method for EUS has not been established. Therefore, this study aimed to examine the safety and complications of sedation with pentazocine or pethidine hydrochloride for outpatient diagnostic EUS.

Methods

We retrospectively reviewed 1302 consecutive cases in our department that underwent outpatient diagnostic EUS between April 2019 and September 2021. Until June 2020, EUS was performed under sedation with midazolam and pentazocine (pentazocine group) in principle; after June 2020, sedation with midazolam and pethidine hydrochloride (pethidine hydrochloride group) was used. A cohort of patients with comparable backgrounds was identified using propensity score matching.

Results

A total of 486 cases were included in this study. Sedation-related adverse events during the endoscopic procedures were not significantly different between the groups. The median time spent in the recovery room after EUS was significantly shorter in the pethidine hydrochloride group than in the pentazocine group (69 versus vs. 77 min; p < 0.001). The frequency of nausea or vomiting after EUS was significantly lower in the pethidine hydrochloride group than in the pentazocine group (0% [0/486] vs. 6.2% [29/486]; p < 0.001). The frequency of readmission to the recovery room after discharge was significantly lower in the pethidine group than in the pentazocine group (0 [0%] vs. 18 [3.7%], respectively; p < 0.001).

Conclusions

The combination of midazolam and pethidine hydrochloride is a more favorable anesthetic than the combination of midazolam and pentazocine for diagnostic EUS in outpatients.

Robotic distal pancreatectomy using the hinotori™ surgical system: Differences in surgical techniques from the daVinci™ surgical system

BACKGROUND

The use of the hinotori™ Surgical System (hinotori) in distal pancreatectomy (DP) is new compared to the da Vinci™ Surgical System (DVSS). The hinotori is equipped with mechanisms distinct from those of DVSS, and comprehensive reports detailing the surgical techniques and outcomes associated with hinotori in DP (hinotori-DP) are lacking. This study aimed to compare the outcomes of DP using the hinotori and DVSS (Xi system), focusing on differences in settings and techniques between the two methods.

METHODS

This study retrospectively investigated consecutive patients who underwent robotic DP from April 2010 (the introduction of robotic DP at our institute) to July 2024. The analysis excluded patients who underwent spleen-preserving procedures or procedures performed using robotic platform other than hinotori or daVinci Xi. The hinotori-DP cases were compared with those performed using DVSS (DVSS-DP). The techniques used in hinotori-DP were examined in more detail.

RESULTS

A total of 75 robotic DP cases (11 with hinotori and 64 with DVSS) were analyzed in this study. Different port configurations and techniques, including a lesser curvature approach, were used in the hinotori-DP compared to DVSS-DP. The operation time was relatively shorter in the hinotori-DP group (299 vs. 366 min, p = 0.095), and the postoperative complication rates were comparable (pancreatic fistula: 27 % vs. 30 %, p = 0.871; Clavien-Dindo Grade ≥3a complications: 18 % vs. 19 %, p = 0.964) between the two groups.

CONCLUSION

The hinotori-DP can be safely performed by focusing on the unique characteristics of the hinotori surgical system.

Role of Endoscopy in Clinical Management of Intraductal Papillary Mucinous Neoplasms

Intraductal papillary mucinous neoplasm (IPMN) of the pancreas is a well-recognized precursor of pancreatic carcinoma. Along with cross-sectional abdominal imaging tests, endoscopic examinations remain the cornerstone in the diagnosis of pancreatic cysts, early detection of IPMN-derived carcinomas, and risk stratification of patients with IPMNs for subsequent surveillance strategies. In particular, endoscopic ultrasound (EUS) facilitates the optimal patient management by providing high-resolution morphological information, and the contrast-enhanced harmonic mode may further enhance diagnostic accuracy. EUS-guided fine-needle aspiration for solid mass and/or cyst fluid is considered for pathological and molecular examinations for the diagnosis of pancreatic cysts and malignancy. Emerging evidence suggests the usefulness of through-the-needle biopsy and confocal laser microendoscopy in this setting. In addition to the undoubtful diagnostic utility, recent studies have demonstrated the potential effect of endoscopic interventions (i.e., ablation) on the control of IPMNs. Despite the increasing role of endoscopy in the clinical management of IPMNs, there remains a gap in our understanding of how to utilize endoscopy in the personalized care for patients with IPMNs (e.g., the optimal interval of EUS) and the prevention of deaths due to pancreatic carcinomas developing concomitantly with IPMNs. This review summarizes the current evidence on the role of endoscopy in both the diagnostic and therapeutic landscapes of clinical management of IPMNs and identifies key clinical unmet needs that should be addressed in future research. Combined with emerging technologies (e.g., artificial intelligence and high-throughput molecular profiling), endoscopy would offer more effective and tailored management strategies for patients with IPMNs.

From classical approaches to artificial intelligence, old and new tools for PDAC risk stratification and prediction

Pancreatic ductal adenocarcinoma (PDAC) is recognized as one of the most lethal malignancies, characterized by late-stage diagnosis and limited therapeutic options. Risk stratification has traditionally been performed using epidemiological studies and genetic analyses, through which key risk factors, including smoking, diabetes, chronic pancreatitis, and inherited predispositions, have been identified. However, the multifactorial nature of PDAC has often been insufficiently addressed by these methods, leading to limited precision in individualized risk assessments. Advances in artificial intelligence (AI) have been proposed as a transformative approach, allowing the integration of diverse datasets-spanning genetic, clinical, lifestyle, and imaging data into dynamic models capable of uncovering novel interactions and risk profiles. In this review, the evolution of PDAC risk stratification is explored, with classical epidemiological frameworks compared to AI-driven methodologies. Genetic insights, including genome-wide association studies and polygenic risk scores, are discussed, alongside AI models such as machine learning, radiomics, and deep learning. Strengths and limitations of these approaches are evaluated, with challenges in clinical translation, such as data scarcity, model interpretability, and external validation, addressed. Finally, future directions are proposed for combining classical and AI-driven methodologies to develop scalable, personalized predictive tools for PDAC, with the goal of improving early detection and patient outcomes.

Diffusion tensor imaging and diffusion kurtosis imaging of the pancreas - feasibility, robustness and protocol comparison in a healthy population

PURPOSE

This study aims to determine the feasibility, image quality, intra-subject repeatability and inter-reader variability of Diffusion tensor (DTI) and Diffusion kurtosis imaging (DKI) for pancreatic imaging using different protocols and report normative values in healthy individuals.

METHODS

Single-institution prospective study performed on healthy volunteers in a clinical 3T scanner, using two different protocols (6/16 diffusion directions). Acquisitions were repeated twice to assess intra-subject repeatability. To assess inter-reader variability, Mean diffusivity (MD), Axial diffusivity (AD), Radial diffusivity (RD), Apparent diffusion coefficient (ADC) and Mean kurtosis (MK) values were extracted from segmented pancreas by two radiologists. A Likert scale was used by both readers to assess subjective image quality.

RESULTS

Twelve healthy volunteers were recruited for each MRI protocol. The 6 diffusion directions protocol was shorter: 7 min vs. 14 min (corresponding to 4 min vs. 7.5 min for a DTI only reconstruction). No differences in image quality were found between protocols. Only MK maps showed implausible estimates, leading to the exclusion of median 16% and 17.7% pixels for the 6- and 16-direction protocols, respectively. Intra-subject repeatability was determined with negligible coefficients of repeatability for DTI; however, MK presented slightly higher values. Inter-reader agreement was excellent for all maps (ICC > 0.9).

CONCLUSIONS

DTI and DKI of the pancreas are feasible in clinical settings, with excellent inter-observer agreement and good image quality. Intra-subject repeatability is excellent for DTI, but some variability was observed with DKI. A 6-directions protocol may be preferred due to faster acquisition without quantitatively compromising estimates. MK inaccuracies prompt further research for improving artifact correction.

Evaluating the Usefulness of the Blood Apolipoprotein A2 Isoform Index for Pancreatic Cancer Diagnosis

Background: Early detection of pancreatic cancer using existing tumor markers is challenging, and novel biomarkers are needed. Apolipoprotein A2 (APOA2), which is not directly produced by tumors, may help detect pancreatic cancer through mechanisms distinct from carbohydrate antigen 19-9 (CA 19-9). This study aimed to evaluate the diagnostic performance of the APOA2-isoform (APOA2-i) Index in patients with pancreatic cancer. Methods: Serum levels of the APOA2-i Index and CA 19-9 were measured in 76 patients with pancreatic cancer (Stage 0, n = 5; I, n = 4; II, n = 15; III, n = 19; and IV, n = 33) and 98 patients with non-pancreatic cancer (intraductal papillary mucinous neoplasm, n = 36; chronic pancreatitis, n = 33; pancreatic neuroendocrine neoplasm, n = 8; autoimmune pancreatitis, n = 9; and others, n = 12) to evaluate diagnostic performance. Results: APOA2 showed lower accuracy for advanced (stages II-IV) pancreatic cancer compared to CA 19-9 (sensitivity, 50.7% vs. 83.6%; sensitivity, 77.6% vs. 87.9%), but it provided superior accuracy for early-stage (stages 0 and I) detection (sensitivity, 33.3% vs. 22.2%; specificity, 66.7% vs. 59.4%). Three early-stage pancreatic cancer cases negative for CA 19-9 were detected with the APOA2-i Index, demonstrating high diagnostic accuracy for early-stage pancreatic cancer when both biomarkers are combined (sensitivity, 44.4%; specificity, 46.7%). The multivariate analysis revealed pancreatic cancer to be an independent risk factor for APOA2-i Index positivity (odds ratio [OR]: 3.48, p < 0.001), CA 19-9 positivity (OR: 25.5, p < 0.001), and positivity for either marker (OR: 13.3, p < 0.001). Conclusions: The APOA2-i Index, combined with CA 19-9, may improve early-stage pancreatic cancer detection, especially in challenging cases and for high-risk patient surveillance.

Risk of pancreatic cancer and high-grade dysplasia in resected main-duct and mixed-type intraductal papillary mucinous neoplasms: A prevalence meta-analysis

BACKGROUND

Current guidelines recommend the resection of main duct- (MD) and mixed-type (MT) intraductal papillary mucinous neoplasms (IPMN) based on specific risk criteria to prevent or treat pancreatic cancer in selected patients. This paradigm follows high rates of malignancy observed in published surgical series. The aim of this systematic review and meta-analysis was to provide robust, pooled rates of invasive carcinoma (IC) and high-grade dysplasia (HGD) in resected MD- and MT-IPMNs of the pancreas.

METHODS

The PubMed, Embase, Scopus, Web of Science, and Cochrane CENTRAL databases were systematically searched. Studies that reported rates of IC or HGD, diagnosed by histopathology of surgical specimens, in MD- or MT-IPMNs were included. Pooled prevalence with 95 % confidence interval (95 % CI) was calculated using a random effects model. Galbraith plots were used to evaluate heterogeneity. Risk of bias was assessed using the National Institutes of Health Quality Assessment Tool.

RESULTS

Based on 51 studies, 59 % (95 % CI: 54 %, 64 %) of resected MD- and MT-IPMN had IC or HGD, with IC in up to 39 % (95 % CI: 33 %, 44 %) of lesions and HGD in 20 % (95 % CI: 16 %, 25 %). Most studies were deemed to be of good quality and Galbraith plots demonstrated high concordance.

CONCLUSIONS

These results confirm the rates of IC and HGD in resected MD/MT-IPMNs. However, a significant proportion of patients have benign lesions, and future research is needed to develop precise diagnostics to distinguish between patients with and without high-risk or cancerous disease.

Lymphoepithelial cyst of the pancreatic tail: a rare entity with surgical and histopathological insights

Lymphoepithelial cysts (LECs) of the pancreas are rare, benign lesions often discovered incidentally during imaging for unrelated conditions. Their radiological features frequently overlap with those of other more common pancreatic cystic lesions, presenting a diagnostic challenge. In this report from a general surgical department on the Australia, we detail the assessment and management of a 54-year-old male with an enlarging pancreatic tail lesion initially thought to be a mucinous cystic neoplasm. Laparoscopic distal pancreatectomy and splenectomy was performed, and subsequent histopathological evaluation confirmed a benign LEC. This report reviews the literature base, clinical presentation, radiological findings, surgical approach, and pathological diagnosis of this rare condition. We emphasize the importance of a tailored approach to management and the role of surgery in definitive treatment.

[Precancerous lesions of the pancreas, prophylactic surgery]

Pancreatic cancer is a serious pathology whose incidence is increasing. Advances in imaging have made it possible to fortuitously highlight more and more cystic pancreatic lesions, some of which have a malignant potential, leading to the consideration of prophylactic excision. The various known precancerous lesions of the pancreas as well as current management recommendations are here reviewed.

Outcomes of pancreatectomy for histologically proven intraductal papillary mucinous neoplasm with reference to Fukuoka guidelines

BACKGROUND

Intraductal papillary mucinous tumour (IPMN) of pancreas is increasingly recognized to have malignant potential. Fukuoka guidelines are commonly used to select patients with IPMN for resection due to high chance of malignancy, which includes high-grade dysplasia (HGD) or invasive carcinoma (IC).

METHODS

A retrospective study on consecutive patients who have undergone pancreatectomy with IPMN as the final pathology was performed. Operative and survival outcomes were analysed. The positive predictive values (PPV) of high-risk stigmata (HRS) and worrisome features (WF) of Fukuoka guidelines for HGD/IC were determined.

RESULTS

Between August 2011 and September 2020, various types of pancreatectomy were performed for 36 patients with histologically proven IPMN. They included 26 pancreaticoduodenectomy, 7 distal pancreatectomy, 2 central pancreatectomy, and 1 total pancreatectomy. There were 30 branch duct type IPMN, 5 main duct type, and 1 mixed type. There was no 30-day mortality. Overall complications and pancreatic fistula occurred in 44.4% and 5.6% of patients, respectively. Patients without HGD/IC had 100% survival at 5 years with no recurrent disease. There were 13 patients with HGD/IC, their 1-, 3-, 5-year overall and disease-free survival were 84.6%, 76.9%, 67.3% and 84.6%, 68.4%, 58.6%, respectively, both significantly shorter than non-HGD/IC group (P = 0.002 and 0.001, respectively). The PPV of HRS and WF for HGD/IC were 33.3% and 23.5%, respectively. The combined PPV of HRS and WF for HGD/IC was 38.0%.

CONCLUSION

Survival after pancreatectomy for IPMN was favourable, but was significantly worse in the presence of HGD/IC. Fukuoka guidelines were useful in predicting malignant IPMN.

Defining and Predicting Early Recurrence for Optimal Treatment Strategies for Intraductal Papillary Mucinous Neoplasm-Derived Pancreatic Cancer: An International Multicenter Study

BACKGROUND

Early recurrence in intraductal papillary mucinous neoplasm (IPMN)-derived pancreatic ductal adenocarcinoma (PDAC) is poorly defined. Predictors are lacking and needed for patient counseling, risk stratification, and postoperative management. This study aimed to define and predict early recurrence for patients in resected IPMN-derived PDAC and guide management.

METHODS

A lowest p value for survival after recurrence (SAR) was used to define early recurrence in resected IPMN-derived PDAC from five international centers. Overall survival (OS) and SAR were compared using log-rank tests. A multivariable logistic regression identified odds ratios (ORs) with 95 % confidence intervals (CIs) for early recurrence. Rounded ORs were used to stratify patients into low-, intermediate-, and high-risk groups using upper and lower quartile score distributions. Adjuvant chemotherapy was assessed by Cox regression and log-rank tests for OS in risk groups.

RESULTS

Recurrence developed in 160 (42 %) of 381 patients. Early recurrence was defined at 10.5 months and observed in 61 patients (38 % of recurrences). The median SAR for the patients with early recurrence was 8.3 months (95 % CI, 3.1-16.1 months) compared with 12.9 months (95 % CI, 5.2-27.5 months) for the patients with late recurrence. The independent predictors of early recurrence were CA19-9 (OR, 3.80; 95 % CI, 1.54-9.41) and N2 disease (OR, 7.29; 95 % CI, 3.22-16.49). The early recurrence rates in the low-, intermediate-, and high-risk groups were respectively 1 %, 14 %, and 32 %. Adjuvant chemotherapy was associated with improved OS only for the high-risk patients (hazard ratio, 0.50; 95 % CI, 0.32-0.79).

CONCLUSION

In IPMN-derived PDAC, the optimal cutoff for early recurrence is 10.5 months. Both CA19-9 and N stage predict early recurrence. Adjuvant chemotherapy is associated with survival benefit only for high-risk patients.

What Is the Latest in Pancreatic Cysts?

Pancreatic cysts are common incidental findings. The understanding of pancreatic cysts has evolved tremendously over the past few decades. Molecular diagnostic and endoscopic techniques have led to more precise characterization of cyst types and interventions to improve patient outcomes. This article outlines these recent innovations in pancreatic cyst diagnosis and management.

The Role of Markedly Elevated Cyst Carcinoembryonic Antigen in Risk-Stratifying Pancreatic Cysts

INTRODUCTION

Carcinoembryonic antigen (CEA) level is currently being used in algorithms of commercially available pancreatic cyst fluid analysis platforms. However, the evidence to date on its role in risk stratification for mucinous lesions is heterogenous. We therefore sought to examine the relationship between the magnitude of CEA elevation and the structural and molecular properties of pancreatic cysts.

METHODS

All patients who underwent pancreatic cyst fluid analysis at a single institution from 2012 to 2019 were retrospectively examined. Structural features on endoscopic ultrasound were analyzed as a function of cyst fluid CEA. A subset of patients who underwent surgical resection was separately analyzed.

RESULTS

A total of 634 pancreatic cyst fluid samples were obtained from 566 patients. Among all samples, 57% had normal cyst fluid CEA. Of those with elevated CEA, 22% had elevations <1000, 13% between 1000 and 10,000, and 8% > 10,000 ng/mL. The CEA >10,000 group had the highest rates of solid components (P = 0.039), mural nodules (P = 0.044), and mean number of DNA abnormalities (P < 0.001). The overall malignancy rate among all patients with cyst CEA >10,000 ng/mL was 14% (n = 7). Importantly, there was a strong association between the magnitude of the CEA elevation and the number of DNA abnormalities (P < 0.001) and the presence of oncogene mutations (P < 0.001).

CONCLUSIONS

In this large dataset of pancreatic cyst fluid aspirates, the magnitude of the CEA elevation was associated with worrisome features. Especially at its most extreme, elevated CEA should be further examined in the assessment of neoplastic risk for patients with an established diagnosis of a mucinous pancreatic cyst.

Pancreatic cancer: Future challenges and new perspectives for an early diagnosis

This editorial is a commentary on the case report by Furuya et al focusing on the challenging diagnosis of early pancreatic adenocarcinoma and new tools for an earlier diagnosis. Currently, pancreatic cancer still has a poor prognosis, mainly due to late diagnosis in an advanced stage. Two main precancerous routes have been identified as pathways to pancreatic adenocarcinoma: The first encompasses a large group of mucinous cystic lesions: intraductal papillary mucinous neoplasm and mucinous cystic neoplasm, and the second is pancreatic intraepithelial neoplasia. In the last decade the focus of research has been to identify high-risk patients, using advanced imaging techniques (magnetic resonance cholangiopancreatography or endoscopic ultrasonography) which could be helpful in finding "indirect signs" of early stage pancreatic lesions. Nevertheless, the survival rate still remains poor, and alternative screening methods are under investigation. Endoscopic retrograde cholangiopancreatography followed by serial pancreatic juice aspiration cytology could be a promising tool for identifying precursor lesions such as intraductal papillary mucinous neoplasm, but confirming data are still needed to validate its role. Probably a combination of cross-sectional imaging, endoscopic techniques (old and new ones) and genetic and biological biomarkers (also in pancreatic juice) could be the best solution to reach an early diagnosis. Biomarkers could help to predict and follow the progression of early pancreatic lesions. However, further studies are needed to validate their diagnostic reliability and to establish diagnostic algorithms to improve prognosis and survival in patients with pancreatic cancer.

Correlation of GNAS Mutational Status with Oncologic Outcomes in Patients with Resected Intraductal Papillary Mucinous Neoplasms

Background: Intraductal papillary mucinous neoplasms (IPMNs) are pre-malignant pancreatic lesions that may progress to invasive pancreatic ductal adenocarcinoma (PDAC). IPMN-associated invasive carcinoma (iIPMN) has been associated with more favorable survival outcomes compared to non-iIPMN-derived PDAC. Here, we aim to investigate the genetic landscape of IPMNs to assess their relevance to oncologic outcomes. Methods: This retrospective study used a large single-institution prospectively maintained database. Patients who underwent curative-intent pancreatic resection between 2016 and 2022 with histologically confirmed diagnosis of IPMN were included. Demographic, pathologic, molecular, and oncologic outcome data were recorded. Kaplan-Meier survival analyses were performed. PDAC data from public genetic databases were used for mutational correlation analysis. p-value ≤ 0.05 was considered as significant. Results: A total of thirty-nine patients with resected IPMN with complete clinical and sequencing data were identified and included in the final cohort. The male-to-female distribution was 21:18, and the mean age was 70.1 ± 9.1 years. GNAS mutations occurred in 23.1% of patients, and 89.7% of patients had iIPMN. In iIPMN patients, GNAS mutation was strongly associated with improved disease-free survival: all GNAS-mutant patients survived to follow-up with significantly fewer recurrences than in GNAS wild-type (WT) patients (p = 0.013). Mutated GNAS closely co-occurred with wild-type KRAS (p < 0.001), and further analysis of large genomic PDAC datasets validated this finding (OR 3.47, p < 0.0001). Conclusions: Our study suggests prognostic value of mutational status in malignant resected IPMNs. WT GNAS, mutant P53, and mutant KRAS each correlate with recurrence and decreased survival. Further studies are required to validate these preliminary observations.

Important radiological and clinicopathological risk factors for the recurrence of intraductal papillary mucinous neoplasms after surgical resection

OBJECTIVES

To assess significant radiological and clinicopathological risk factors for post-surgery recurrence in patients with intraductal papillary mucinous neoplasm (IPMN).

MATERIALS AND METHODS

Patients with IPMNs who underwent surgery from 2011 to 2021 at a single center were retrospectively included. Two reviewers evaluated CT findings according to international guidelines. Clinicopathological data were collected from medical records and surgical pathology reports. Patients were monitored for recurrence with contrast-enhanced CT or MRI up to 2023. Univariable Cox regression analysis included potential risk factors: all high-risk stigmata and worrisome features in the international guidelines, age, sex, tumor location, type, carcinoembryonic antigen, surgery type, postsurgical residual cyst, adjuvant treatment, pathologic grade, type, size, margin status, lymph node metastasis, gland type, and pancreatic intraepithelial neoplasia. Variables with p < 0.2 were included in multivariate analysis.

RESULTS

Among 332 patients (mean age, 66.3 ± 9.0 years; 212 men), recurrence occurred in 39 (11.7%) over a median follow-up of 3.2 years (range: 0.1-12.3 years). Two- and five-year recurrence-free survival rates were 91.2% and 86.4%, respectively. Significant radiological risk factors included enhancing mural nodule (EMN) presence (hazard ratio [HR] 5.088, p = 0.007) and lymphadenopathy (HR 2.837, p = 0.01). Associated invasive carcinoma (HR 25.030), lymph node metastasis (HR 27.562), adjuvant treatment (HR 0.203), and history of pancreatitis (HR 2.608) were also significant. Most imaging features showed moderate to excellent interobserver agreement, except for thickened/enhancing cyst walls (κ, 0.25).

CONCLUSION

The presence of EMNs and lymphadenopathy, along with several clinicopathologic factors, were significantly associated with IPMN recurrence.

KEY POINTS

Question Understanding postoperative recurrence risk in IPMN patients is crucial for determining surveillance strategies; however, research on radiologic risk factors remains limited. Findings The presence of EMNs and lymphadenopathy were identified as significant radiologic risk factors for the postoperative recurrence of IPMN, along with clinicopathologic factors. Clinical relevance IPMN recurrence is significantly associated with imaging findings like EMNs and lymphadenopathy, as well as clinical and pathologic factors. It can guide the development of tailored postoperative surveillance strategies for IPMN patients in further studies.

Cystic Fluid Total Proteins, Low-Density Lipoprotein Cholesterol, Lipid Metabolites, and Lymphocytes: Worrisome Biomarkers for Intraductal Papillary Mucinous Neoplasms

Objectives: Pancreatic cystic neoplasms (PCNs), particularly intraductal papillary mucinous neoplasms (IPMNs), present a challenge for their potential malignancy. Despite promising biomarkers like CEA, amylase, and glucose, our study investigates whether metabolic indices in blood and cystic fluids (CFs), in addition to lymphocyte subsets and hematopoietic stem/progenitor cells (HSPCs), can effectively differentiate between high- and low-risk PCNs. Materials and Methods: A total of 26 patients (11 males, mean age 69.5 ± 9 years) undergoing Endoscopic Ultrasound-guided Fine Needle Aspiration were consecutively enrolled. Analyses included blood, serum, and CF, assessing glucose, CEA, cholesterol (total, HDL, and LDL), and total proteins. Flow cytometry examined immunophenotyping in peripheral blood and cystic fluids. Mass spectrometry was used for the metabolomic analysis of CF. Sensitivity, specificity, and ROC analyses evaluated discriminatory power. Results: A total of 25 out of 26 patients had IPMN. Patients were categorized as low or high risk based on multidisciplinary evaluation of clinical, radiological, and endoscopic data. High-risk patients showed lower CF total proteins and LDL cholesterol (p = 0.005 and p = 0.031), with a marked reduction in CF lymphocytes (p = 0.005). HSCPs were absent in CF. In blood, high-risk patients showed increased non-MHC-restricted cytotoxic T cells (p = 0.019). The metabolomic analysis revealed significantly reduced middle and long-chain acyl carnitines (AcCa) and tryptophan metabolites in high-risk patients. ROC curves indicated comparable discriminant abilities for CF lymphocytes (AUC 0.868), CF total proteins (AUC 0.859), and CF LDL cholesterol (AUC 0.795). The highest performance was achieved by the AcCa 14:2 and 16:0 (AUC: 0.9221 and 0.8857, respectively). Conclusions: CF levels of glucose, CEA, LDL cholesterol, and total proteins together with lymphocyte counts are easy translational biomarkers that may support risk stratification of PCNs in IPMN patients and might be endorsed by metabolomic analysis. Further studies are required for potential clinical integration.

A single-center study examining the safety and effectiveness of ERCP with pancreatoscopy and endoluminal radiofrequency ablation for main-duct IPMN treatment

To assess the safety and efficacy of treatment for intraductal papillary mucinous neoplasm (IPMN) involving the main pancreatic duct (MPD) using endoscopic retrograde cholangiopancreatography (ERCP) combined with digital single-operator pancreatoscopy and radiofrequency ablation (RFA). A retrospective analysis was performed. Patients with episodes of acute pancreatitis at the First Affiliated Hospital of Chongqing Medical University were screened. When the diagnosis of IPMN was confirmed by ERCP with pancreatoscopy, patients who underwent endoluminal RFA treatment were enrolled. The most frequent complications were monitored to assess the safety of treatment. Disease progression and recurrence of pancreatitis symptoms were regarded as the indicators of treatment efficacy. In total, 50 patients were screened, and 14 patients who undertook the lesion ablation using RFA were enrolled. Mild adverse events occurred, while they were relieved under symptomatic treatment. No severe complications were recorded. All patients received regular follow-ups, during which an episode of IPMN-related pancreatitis occurred in 1 patient, and disease progression was found in 1 patient who successively underwent pancreaticoduodenectomy. Regional treatment of IPMN lesions in the MPD exhibited satisfactory effect in preventing lesion progression and relieving pancreatitis symptoms through the combined use of ERCP with pancreatoscopy and RFA, without causing severe complications.

Older Age as a Worrisome Feature in Patients With Intraductal Papillary Mucinous Neoplasms: A Long-Term Surveillance Study

INTRODUCTION

Aging has been implicated in the development of various cancer types. No study has specifically investigated age at intraductal papillary mucinous neoplasm (IPMN) diagnosis in relation to the long-term risk of pancreatic carcinogenesis.

METHODS

Within a prospective cohort of 4,104 patients diagnosed with pancreatic cysts, we identified 3,142 patients with IPMNs and examined an association of age at IPMN diagnosis with the incidence of pancreatic carcinoma. Using the multivariable competing-risks proportional hazards regression model, we estimated subdistribution hazard ratios (SHRs) and 95% confidence intervals (CIs) for pancreatic carcinoma incidence according to age at IPMN diagnosis.

RESULTS

During 22,187 person-years of follow-up, we documented 130 patients diagnosed with pancreatic carcinoma (64 with IPMN-derived carcinoma and 66 with concomitant ductal adenocarcinoma). Older age at IPMN diagnosis was associated with a higher risk of pancreatic cancer incidence ( Ptrend = 0.002). Compared with patients younger than 55 years, patients aged 55-64, 65-74, and ≥ 75 years had adjusted SHRs of 1.80 (95% CI, 0.75-4.32), 2.56 (95% CI, 1.10-5.98), and 3.31 (95% CI, 1.40-7.83), respectively. Patients aged 70 years and older had a numerically similar adjusted SHR compared with patients younger than 70 years with worrisome features defined by the international consensus guidelines (1.73 [95% CI, 1.01-2.97] and 1.66 [95% CI, 0.89-3.10], respectively).

DISCUSSION

Older patients with IPMNs were at a higher risk of developing pancreatic carcinoma during surveillance. Surgically fit elderly patients may be good candidates for periodic surveillance aimed at a reduction of pancreatic cancer-related deaths.

Optimal indication of adding pancreatic juice cytology in the diagnosis of malignant intraductal papillary mucinous neoplasm of the pancreas

BACKGROUND/OBJECTIVES

Positive pancreatic juice cytology (PJC) is an important finding when considering surgical resection in patients with intraductal papillary mucinous neoplasm (IPMN); however, guidelines do not recommend endoscopic retrograde cholangiopancreatography (ERCP) for PJC. This study aimed to clarify the findings worthy of adding PJC for diagnosing high-grade dysplasia (HGD) and invasive carcinoma (IC) in patients with IPMN.

METHODS

Patients with IPMN who underwent preoperative PJC and surgical resection at Hiroshima University Hospital were enrolled, and the diagnostic yield of malignant IPMN based on PJC and clinical and imaging findings and the incidence of post-ERCP pancreatitis (PEP) were retrospectively analyzed.

RESULTS

Of the 129 eligible patients, 61 (47%) had malignant tumors (29 HGD and 32 IC). The diagnostic yields of PJC were as follows: 33%, 97%, 91%, 62%, and 67% for sensitivity, specificity, and positive predictive value, and negative predictive value, respectively. Multivariate analysis revealed that an abrupt change in the pancreatic duct caliber was an independent predictive factor of true-positive PJC (hazard ratio: 15.81, P = 0.001), with a diagnostic sensitivity of 86% for PJC in these patients. The incidence rate of PEP was 19%, and the pancreatic body and tail lesions, main pancreatic duct diameter <10 mm, and placement of a nasopancreatic drainage catheter were significant risk factors for PEP.

CONCLUSIONS

Although PJC is generally not recommended for patients with IPMN, it is worth considering for the determination of treatment strategies in patients with abrupt changes in the caliber of the pancreatic duct with distal pancreatic atrophy.

An imaging-based model to predict the malignant potential of intraductal papillary mucinous neoplasm of the pancreas

OBJECTIVES

To develop and validate imaging-based models for predicting the malignancy risk of intraductal papillary mucinous neoplasm (IPMN).

MATERIALS AND METHODS

We retrospectively analyzed data from 241 IPMN patients who underwent preoperative CT and MRI for model development. Cyst size, presence and size of the enhancing mural nodule (EMN), main pancreatic duct (MPD) diameter, thickened/enhancing cyst wall, abrupt MPD caliber change with distal atrophy, and lymphadenopathy were assessed. Multiple logistic regression models predicting malignancy risk were created using either continuous (Model C) or dichotomized variables (Model D) using these imaging features. Validation included internal (n = 55) and external (n = 43) datasets. Model performance was assessed using the area under the receiver operating characteristic curve (AUC) and compared with that of the international guideline-based model (Model F).

RESULTS

Model C identified age, EMN size, MPD diameter, and lymphadenopathy as independent predictors on CT, and age and presence and size of EMN on MRI. Model D identified age ≥ 68, cyst size ≥ 31 mm, EMN ≥ 6 mm, MPD ≥ 7 mm, and lymphadenopathy as independent predictors on CT, and age ≥ 68, EMN ≥ 4.5 mm, and lymphadenopathy on MRI. Model C (AUC, 0.763-0.899) performed slightly better than Model D (AUC, 0.753-0.912) without statistical significance. No significant difference was observed between Models C and F (AUC, 0.729-0.952). Combining Model C with obstructive jaundice improved performance (AUC, 0.802-0.941) without statistical significance.

CONCLUSION

Our imaging-based models effectively predicted the malignancy risk of IPMNs, comparable to international consensus guidelines.

CLINICAL RELEVANCE STATEMENT

Imaging features are important for predicting the malignant potential of IPMNs. Our imaging-based model may help determine surgical candidacy for patients with IPMNs.

KEY POINTS

Non-invasively determining the malignant potential of intraductal papillary mucinous neoplasms (IPMNs) allows for appropriate treatment decision-making We identified multiple imaging features that are associated with malignant transformation and developed models for this prediction. Our model performs comparably with international consensus guidelines in predicting the malignant potential of IPMNs.

Clinical significance of intraductal papillary mucinous neoplasms incidentally detected in patients with extrapancreatic gastrointestinal malignancies with a focus on pancreatic cancer development

BACKGROUND

Intraductal papillary mucinous neoplasm is occasionally detected in the preoperative images of patients with gastrointestinal malignancies. Despite numerous studies examining the incidence of extrapancreatic malignancies in patients with intraductal papillary mucinous neoplasm, limited data exist on the prevalence of intraductal papillary mucinous neoplasm in those with gastrointestinal malignancies. Given that intraductal papillary mucinous neoplasm is a known risk factor for pancreatic cancer, this study aimed to evaluate the prevalence of intraductal papillary mucinous neoplasm in patients who underwent radical surgery for extrapancreatic gastrointestinal malignancies and its impact on pancreatic cancer development.

METHODS

We retrospectively reviewed the preoperative computed tomography images of patients who underwent radical surgery for gastrointestinal malignancies between January 2017 and December 2021 for the presence of intraductal papillary mucinous neoplasm. Patients were divided into intraductal papillary mucinous neoplasm and non-intraductal papillary mucinous neoplasm groups, and clinicopathologic features and long-term outcomes, including pancreatic cancer development, were compared between groups.

RESULTS

A total of 814 patients who underwent radical surgery for extrapancreatic gastrointestinal malignancies were included. Among them, 81 patients (10.0%) had intraductal papillary mucinous neoplasm. The median observation period was 39 (0-79) months. Notably, pancreatic cancer developed in 5 patients with intraductal papillary mucinous neoplasm and 1 without. The 5-year cumulative incidences of pancreatic cancer were 8.8% and 0.2% in the intraductal papillary mucinous neoplasm and non-intraductal papillary mucinous neoplasm groups, respectively (P < .001).

CONCLUSION

Intraductal papillary mucinous neoplasm is frequently detected in the preoperative images of patients with gastrointestinal malignancies and is associated with a significantly higher risk of developing pancreatic cancer. Consequently, long-term surveillance for pancreatic cancer is crucial in patients with intraductal papillary mucinous neoplasm, particularly those with extrapancreatic gastrointestinal malignancies.

Endoscopic retrograde cholangiopancreatography: A comprehensive review as a single diagnostic tool

Endoscopic retrograde cholangiopancreatography (ERCP) was initially introduced in clinical practice as diagnostic tool. However, the presence of adverse events and the development of non-invasive techniques, such as magnetic resonance cholangiopancreatography (MRCP) and endoscopic ultrasound (EUS), limited its role as a stand-alone diagnostic choice, modifying its role to the leader of therapeutic pancreatobiliary endoscopy. Despite technological advances, there are still conditions where non-invasive diagnostic modalities are inconclusive, such as indeterminate biliary and pancreatic duct strictures, primary sclerosing cholangitis functional stenoses, intraductal papillary mucinous neoplasms (IPMNs) and paediatric indications, such as congenital anatomical abnormalities. This narrative review aimed to identify and analyse indications of diagnostic ERCP, without the need for therapeutic manipulations.

Reducing the burden of pancreatic cancer by surveilling mucinous cystic neoplasms: are we there yet?

Pancreatic cystic neoplasms are a common condition, with intraductal papillary mucinous neoplasms (IPMNs) and mucinous cystic neoplasms (MCNs) being of particular concern due to their potential for malignant transformation. Resection of these lesions before progression to invasive cancer represents a crucial opportunity to reduce the burden of pancreatic cancer. However, the benefit of early-resection must be weighed against the risk of overtreatment. Applying current guidelines, nearly half of the patients who undergo resection for IPMN might not have required surgery, while malignancy is detected in only 16 % of resected MCNs. This raises concerns, particularly given the increasing detection of small cysts with the widespread use of radiological imaging and the significant postoperative risks, including exocrine and endocrine insufficiency. Emerging evidence suggests that surveillance strategies could be more broadly applied, reducing unnecessary surgeries. This review aims to reassess the current evidence regarding both surgical resection and surveillance of IPMNs and MCNs.

Small cyst size and lack of growth as negative predictors of malignant transformation in low-risk intraductal papillary mucinous neoplasms of the pancreas: A systematic review and meta-analysis

BACKGROUND AND AIM

For branch-duct intraductal papillary mucinous neoplasms (BD-IPMNs) without worrisome features (WFs) or high-risk stigmata (HRS), current guidelines recommend surveillance. However, these intraductal papillary mucinous neoplasm (IPMNs), especially the small and stable-sized ones, carry a low risk of malignant transformation. Our aim was to assess whether small cyst size and absence of rapid growth provide reassurance against the development of WFs/HRS and malignancy (high-grade dysplasia (HGD) or pancreatic cancer (PC)).

METHODS

PubMed/Medline, Embase, the Cochrane Library and the Web of Science Core Collection were systematically searched from inception to May 2023 to identify studies investigating surveillance outcomes of low-risk BD-IPMNs. Studies assessing baseline cyst size and/or growth in relation to WFs/HRS and/or HGD/PC were included. The Newcastle-Ottawa scale tool was used to assess study quality.

RESULTS

Of the 1937 identified manuscripts, 21 studies were eligible for inclusion. The quality of these studies was considered reasonable. A negative association between cyst size and WFs/HRS development was found in 11 out of 13 relevant studies, but only one out of nine studies reported a negative association between size and malignancy. Regarding cyst growth, four out of six studies described a negative association with the development of WFs/HRS, and all six reported a negative association with malignancy. The pooled relative risk (RR) of developing WFs/HRS or malignancy for cysts ≤15 mm was 0.37 (95% CI 0.25-0.57) and the RR of developing malignancy for cyst growth <2-2.5 mm/year was 0.04 (95% CI 0.02-0.09)).

CONCLUSION

This systematic review and meta-analysis shows that small and stable-sized low-risk BD-IPMNs are associated with a markedly low progression rate, with stable cyst size being the most reassuring feature. Because of substantial heterogeneity in definitions and reported outcome measures, prospective studies are needed to confirm that surveillance of small and stable sized cyst can be de-intensified or even discontinued.

Risk factors for pancreatic cancer in individuals with intraductal papillary mucinous neoplasms and no high-risk stigmata during up to 5 years of surveillance: a prospective longitudinal cohort study

BACKGROUND

Cyst size, its growth rate, and diameter of the main pancreatic duct (MPD) are all associated with pancreatic carcinoma prevalence in intraductal papillary mucinous neoplasms (IPMNs).

OBJECTIVE

To examine the above factors in relation to future risk of incident pancreatic carcinoma in individuals with IPMNs harbouring no high-risk stigmata.

DESIGN

In a prospective longitudinal cohort, we analysed 2549 patients with IPMNs. A multivariable cause-specific Cox proportional hazards regression model was built to estimate HRs for incident pancreatic carcinoma.

RESULTS

IPMN size at baseline and its annual growth rate over 2 years of follow-up were associated with incident pancreatic carcinoma (ptrend<0.001). The multivariable cause-specific HR per 10 mm increase in IPMN size was 1.28 (95% CI 1.10 to 1.50). The annual growth rates of 1.5-2.4 mm/year and ≥2.5 mm/year over 2 years were associated with multivariable cause-specific HRs of 1.91 (95% CI 0.78 to 4.67) and 4.52 (95% CI 2.28 to 8.98), respectively (vs <1.5 mm/year). Neither IPMN size at 5 years nor its maximum growth rate during 5 years was associated with incident pancreatic carcinoma (ptrend>0.07). MPD diameter at 5 years was associated with incident pancreatic carcinoma (multivariable cause-specific HR per 2 mm increase, 2.12; 95% CI 1.72 to 2.63). A predictive nomogram was generated for calculating the risk of incident pancreatic carcinoma.

CONCLUSION

IPMN size and its growth rate predict future pancreatic carcinoma risk only during first 5 years of follow-up. MPD diameter at 5 years may identify patients who still harbour a high risk for pancreatic carcinoma.

Prediction of main pancreatic duct involvement in intraductal papillary mucinous neoplasms on magnetic resonance imaging

PURPOSE

To evaluate the measurement of main pancreatic duct (MPD) diameter on MRI for predicting MPD involvement in intraductal papillary mucinous neoplasms (IPMN).

METHODS

This retrospective study included 595 patients with surgically confirmed IPMN who underwent preoperative MRI from 2015 to 2022. Three independent readers measured the maximum MPD diameter on two-dimensional axial and coronal T2-weighted imaging. Inter-plane and inter-reader agreements were assessed using the intraclass correlation coefficient (ICC). Multivariable logistic regression identified clinical and radiological factors associated with MPD involvement. Accuracy, sensitivity, and specificity of MPD diameter cutoffs, including the 5-mm threshold from the 2024 International Consensus Guidelines, were calculated.

RESULTS

Of the 595 patients (mean age: 64.6 years ± 8.6, 394 men), 423 (71.1%) had IPMN with MPD involvement, whereas 172 (28.9%) did not have MPD involvement. The mean maximum MPD diameter was 7.9 ± 5.1 mm. Inter-plane agreement was excellent (ICC = 0.977-0.988), as was inter-reader agreement (ICC = 0.963). Only a large MPD diameter on MRI was independently associated with MPD involvement (odds ratio = 1.29 [95% confidence interval; 1.14-1.47], p <.01). Use of a maximum MPD diameter cutoff of ≥ 5 mm for MPD involvement yielded accuracy, sensitivity, and specificity of 76.0%, 79.2%, and 68.0%, respectively.

CONCLUSION

Despite excellent inter-plane and inter-reader agreement, the MRI-based prediction of MPD involvement in IPMN has limitations.

Diagnostic Accuracy of Detective Flow Imaging Endoscopic Ultrasonography for Evaluating Blood Flow Within Mural Nodules of Intraductal Papillary Mucinous Neoplasms

Background/Objectives: Detective flow imaging (DFI) endoscopic ultrasonography (EUS) can identify the microvascular flow imaging of a mural nodule (MN) in an intraductal papillary mucinous neoplasm (IPMN) without the use of contrast agents. This retrospective study evaluated the diagnostic accuracy of DFI-EUS and its ability to evaluate the blood flow of MNs in IPMNs. Methods: Between April 2021 and September 2023, 68 patients with MNs in IPMNs observed on EUS images were retrospectively analyzed. Both DFI-EUS and contrast-enhanced EUS (CE-EUS) were performed during the same session. Three expert endosonographers blinded to the patients' clinical data assessed the MN images obtained with CE-EUS and DFI-EUS. First, DFI-EUS images were evaluated using a predefined scoring system; thereafter, CE-EUS images were evaluated. The diagnostic capability of DFI-EUS to detect MN blood flow was assessed with CE-EUS as the gold standard. Secondary outcomes included inter-reader agreement, the correlation between MN size and detection rates, and the association between DFI blood flow signal patterns and malignancy of MNs in surgically resected cases. Results: CE-EUS showed a contrast effect in the MN in 24 cases. Among these, DFI-EUS detected blood flow signals in 20 cases; false-positive results were not observed. DFI-EUS demonstrated a sensitivity of 83%, specificity of 100%, and accuracy of 93% for detecting MN blood flow. Inter-reader agreement was substantial (kappa values, 0.6-0.8). The subgroup analysis revealed that all MNs ≥ 10 mm had detectable blood flow on DFI-EUS, whereas MNs < 10 mm had reduced detection rates (75%; 12/16 cases). No significant correlation between the DFI blood flow signal patterns and MN malignancy of resected cases was observed. Conclusions: DFI-EUS demonstrated high diagnostic accuracy for detecting MN blood flow. Because of its simplicity and cost-effectiveness, DFI-EUS could be an alternative to CE-EUS for patients with MNs inside IPMNs.

Retrospective analysis of pathological types and imaging features in pancreatic cancer: A comprehensive study

BACKGROUND

Pancreatic cancer remains one of the most lethal malignancies worldwide, with a poor prognosis often attributed to late diagnosis. Understanding the correlation between pathological type and imaging features is crucial for early detection and appropriate treatment planning.

AIM

To retrospectively analyze the relationship between different pathological types of pancreatic cancer and their corresponding imaging features.

METHODS

We retrospectively analyzed the data of 500 patients diagnosed with pancreatic cancer between January 2010 and December 2020 at our institution. Pathological types were determined by histopathological examination of the surgical specimens or biopsy samples. The imaging features were assessed using computed tomography, magnetic resonance imaging, and endoscopic ultrasound. Statistical analyses were performed to identify significant associations between pathological types and specific imaging characteristics.

RESULTS

There were 320 (64%) cases of pancreatic ductal adenocarcinoma, 75 (15%) of intraductal papillary mucinous neoplasms, 50 (10%) of neuroendocrine tumors, and 55 (11%) of other rare types. Distinct imaging features were identified in each pathological type. Pancreatic ductal adenocarcinoma typically presents as a hypodense mass with poorly defined borders on computed tomography, whereas intraductal papillary mucinous neoplasms present as characteristic cystic lesions with mural nodules. Neuroendocrine tumors often appear as hypervascular lesions in contrast-enhanced imaging. Statistical analysis revealed significant correlations between specific imaging features and pathological types (P < 0.001).

CONCLUSION

This study demonstrated a strong association between the pathological types of pancreatic cancer and imaging features. These findings can enhance the accuracy of noninvasive diagnosis and guide personalized treatment approaches.

Endoscopic-Ultrasound-Guided Radiofrequency Ablation for Pancreatic Tumors

Endoscopic ultrasound (EUS)-guided radiofrequency ablation (RFA) is a promising minimally invasive technique for the treatment of pancreatic lesions. This review first focuses on the technical aspects in EUS-RFA: the procedure typically employs EUS probes with integrated radiofrequency electrodes, enabling accurate targeting and ablation of pancreatic lesions. Different types of RFA devices, monopolar and bipolar energy delivery systems, are discussed, along with considerations for optimal ablation, including energy settings, procedure time, and pre- and post-procedural management. This paper presents a comprehensive literature review of EUS-RFA applied to both solid and cystic pancreatic lesions, including functioning and non-functioning pancreatic neuroendocrine tumors (pNETs), pancreatic cystic lesions (PCLs), pancreatic ductal adenocarcinoma (PDAC), and pancreatic metastases (PMs), discussing current evidence on safety, efficacy, clinical outcomes, and adverse events (AEs). EUS-RFA is an emerging technique with expanding potential for the treatment of both benign and malignant conditions; however, further studies are needed to better define patient selection criteria, assess long-term benefits, and establish definitive indications for its use.

Artificial Intelligence in Pancreatic Intraductal Papillary Mucinous Neoplasm Imaging: A Systematic Review

Background

Based on the Fukuoka and Kyoto international consensus guidelines, the current clinical management of intraductal papillary mucinous neoplasm (IPMN) largely depends on imaging features. While these criteria are highly sensitive in detecting high-risk IPMN, they lack specificity, resulting in surgical overtreatment. Artificial Intelligence (AI)-based medical image analysis has the potential to augment the clinical management of IPMNs by improving diagnostic accuracy.

Methods

Based on a systematic review of the academic literature on AI in IPMN imaging, 1041 publications were identified of which 25 published studies were included in the analysis. The studies were stratified based on prediction target, underlying data type and imaging modality, patient cohort size, and stage of clinical translation and were subsequently analyzed to identify trends and gaps in the field.

Results

Research on AI in IPMN imaging has been increasing in recent years. The majority of studies utilized CT imaging to train computational models. Most studies presented computational models developed on single-center datasets (n=11,44%) and included less than 250 patients (n=18,72%). Methodologically, convolutional neural network (CNN)-based algorithms were most commonly used. Thematically, most studies reported models augmenting differential diagnosis (n=9,36%) or risk stratification (n=10,40%) rather than IPMN detection (n=5,20%) or IPMN segmentation (n=2,8%).

Conclusion

This systematic review provides a comprehensive overview of the research landscape of AI in IPMN imaging. Computational models have potential to enhance the accurate and precise stratification of patients with IPMN. Multicenter collaboration and datasets comprising various modalities are necessary to fully utilize this potential, alongside concerted efforts towards clinical translation.

Advances in Endoscopic Ultrasonography-Based Diagnosis of Pancreatic Lesions: Narrative Review

Pancreatic cancer is the fourth deadliest cancer in the U [...].

Endoscopic techniques for the diagnosis of pancreatic cystic lesions

Pancreatic cysts are mostly incidental findings on computed tomography or magnetic resonance imaging scans, with few patients presenting with abdominal pain or other symptoms. The accurate diagnosis of cysts is important as management depends on the type (neoplastic or non-neoplastic). Cross-sectional imaging is fast being replaced with endoscopic ultrasound (EUS) and various techniques based on that such as EUS-guided fine needle aspiration, EUS-guided needle confocal laser endomicroscopy, EUS-through-the-needle biopsy, and contrast-enhanced EUS. Clinical studies have reported varying diagnostic and adverse event rates with these modalities. In addition, American, European, and Kyoto guidelines for the diagnosis and management of pancreatic cysts have provided different recommendations. In this editorial, we elaborate on the clinical guidelines, recent studies, and comparison of different endoscopic methods for the diagnosis of pancreatic cysts.

Acute pancreatitis in intraductal papillary mucinous neoplasm: Associations with epithelial subtype, degree of dysplasia, and risk of recurrence

BACKGROUND

Acute pancreatitis is an uncommon presentation of intraductal papillary mucinous neoplasm; however, it is considered a worrisome feature in current guidelines and can be an indication for surgery. There is controversy regarding its association with malignancy, and there is little information regarding the recurrence of pancreatitis after surgical resection.

METHODS

We retrospectively reviewed patients who underwent resection for intraductal papillary mucinous neoplasm at a single institution between January 1990 and December 2023. Patients with and without acute pancreatitis as part of the clinical presentation were compared.

RESULTS

A total of 812 patients were reviewed. Of these, 156 patients (19.2%) had intraductal papillary mucinous neoplasms associated with acute pancreatitis, and in 92% of them pancreatitis was the symptom leading to the diagnosis. Half of the patients had a single episode of pancreatitis (n = 77, 49.4%), and 42 (26.9%) had had 3 or more episodes before diagnosis. Acute pancreatitis was significantly associated with high-grade dysplasia (odds ratio 2.07) but had a lower likelihood of invasive cancer (odds ratio 0.62). It was also significantly associated with main duct and mixed duct-type intraductal papillary mucinous neoplasm (odds ratio 1.97) and intestinal epithelial subtype (odds ratio 2.28). Median follow-up for all patients was 61 months, and the likelihood of recurrent pancreatitis after surgical resection was 9% (14 patients), whereas pancreatitis after resection in patients without prior history occurred in only 0.9% (6 patients, P < .001).

CONCLUSIONS

Almost 1 in 5 patients undergoing resection for intraductal papillary mucinous neoplasm have a history of acute pancreatitis and are twice as likely to have high-grade dysplasia, supporting its categorization as a worrisome feature. Recurrence of pancreatitis after resection was 9%.