Intraductal Papillary Mucinous Neoplasm Research Articles

Comprehensive Assessment of the Intrinsic Pancreatic Microbiome.

We sought to comprehensively profile tissue and cyst fluid in patients with benign, precancerous, and cancerous conditions of the pancreas to characterize the intrinsic pancreatic microbiome. Small studies in pancreatic ductal adenocarcinoma (PDAC) and intraductal papillary mucinous neoplasm (IPMN) have suggested that intra-pancreatic microbial dysbiosis may drive malignant transformation. Pancreatic samples were collected at the time of resection from 109 patients. Samples included tumor tissue (control, n=20; IPMN, n=20; PDAC, n=19) and pancreatic cyst fluid (IPMN, n=30; SCA, n=10; MCN, n=10). Assessment of bacterial DNA by quantitative PCR and 16S ribosomal RNA gene sequencing was performed. Downstream analyses determined the relative abundances of individual taxa between groups and compared intergroup diversity. Whole-genome sequencing data from 140 patients with PDAC in the National Cancer Institute's Clinical Proteomic Tumor Analysis Consortium (CPTAC) were analyzed to validate findings. Sequencing of pancreatic tissue yielded few microbial reads regardless of diagnosis, and analysis of pancreatic tissue showed no difference in the abundance and composition of bacterial taxa between normal pancreas, IPMN, or PDAC groups. Low-grade dysplasia (LGD) and high-grade dysplasia (HGD) IPMN were characterized by low bacterial abundances with no difference in tissue composition and a slight increase in Pseudomonas and Sediminibacterium in HGD cyst fluid. Decontamination analysis using the CPTAC database confirmed a low-biomass, low-diversity intrinsic pancreatic microbiome that did not differ by pathology. Our analysis of the pancreatic microbiome demonstrated very low intrinsic biomass that is relatively conserved across diverse neoplastic conditions and thus unlikely to drive malignant transformation.

Defining the Minimal and Optimal Thresholds for Lymph Node Resection and Examination for Intraductal Papillary Mucinous Neoplasm Derived Pancreatic Cancer: A Multicenter Retrospective Analysis.

To establish minimal and optimal lymphadenectomy thresholds for intraductal papillary mucinous neoplasm (IPMN)-derived pancreatic ductal adenocarcinoma (PDAC) and evaluate their prognostic value. Current guidelines recommend a minimum of 12-15 lymph nodes (LNs) in PDAC. This is largely based on pancreatic intraepithelial neoplasia (PanIN)-derived PDAC, a biologically distinct entity from IPMN-derived PDAC. Multicenter retrospective study including consecutive patients undergoing upfront surgery for IPMN-derived PDAC was conducted. The minimum cut-off for lymphadenectomy was defined as the maximum number of LNs where a significant node positivity difference was observed. Maximally selected log-rank statistic was used to derive the optimal lymphadenectomy cut-off (maximize survival). Kaplan-Meier curves and log-rank tests were used to analyze overall survival (OS) and recurrence-free survival (RFS). Multivariable Cox-regression was used to determine hazard ratios (HR) with 95% confidence intervals (95%CI). In 341 patients with resected IPMN-derived PDAC, the minimum number of LNs needed to ensure accurate nodal staging was 10 (P=0.040), whereas ≥20 LNs was the optimal number associated with improved OS (80.3 vs. 37.2mo, P<0.001). Optimal lymphadenectomy was associated with improved OS [HR:0.57 (95%CI 0.39-0.83)] and RFS [HR:0.70 (95%CI 0.51-0.97)] on multivariable Cox-regression. On sub-analysis the optimal lymphadenectomy cut-offs for pancreatoduodenectomy, distal pancreatectomy, and total pancreatectomy were 20 (P<0.001), 23 (P=0.160), and 25 (P=0.008). In IPMN-derived PDAC, lymphadenectomy with at least 10 lymph nodes mitigates under-staging, and at least 20 lymph nodes is associated with the improved survival. Specifically, for pancreatoduodenectomy and total pancreatectomy, 20 and 25 lymph nodes were the optimal cut-offs.

Effective abdominal ultrasonographic detection of pancreatic cystic lesions using artificial intelligence‐assisted noise reduction

AbstractIntroductionPatients with intraductal papillary mucinous neoplasms (IPMNs) exhibit a high incidence of pancreatic cancer. An IPMN presents as a pancreatic cystic lesion (PCL). Artificial intelligence (AI) can be used to enhance ultrasonographic images. We retrospectively evaluated the utility of AI‐assisted ultrasonography in terms of PCL detection.MethodsIn total, 969 patients who underwent artificial narrow intelligence‐assisted transabdominal ultrasound examinations (AI group) were compared with 943 patients who underwent non‐AI‐assisted examinations (control group). The morphological changes and the frequencies of newly detected PCLs were compared between the groups.ResultsThe PCL detection rate was significantly higher in the AI group than in the control group (1.25 ± 0.36 and 0.21 ± 0.15%, respectively; p = .008). AI‐assisted ultrasound evaluation was independently associated with enhanced PCL detection (odds ratio: 5.83, 95% confidence interval: 1.29–26.29, p = .02). PCLs smaller than 8 mm and all PCLs in the pancreatic tail were detected in the AI group.PCL morphological changes were more common in the AI group than in the control group (63.6 ± 14.5 and 16.7 ± 15.2%, respectively; p = .04).ConclusionAI‐assisted transabdominal ultrasonography enhances the PCL detection rate. The use of AI is likely to increase the IPMN detection rate.

ABCD1 as a Novel Diagnostic Marker for Solid Pseudopapillary Neoplasm of the Pancreas.

The diagnosis of solid pseudopapillary neoplasm of the pancreas (SPN) can be challenging due to potential confusion with other pancreatic neoplasms, particularly pancreatic neuroendocrine tumors (NETs), using current pathological diagnostic markers. We conducted a comprehensive analysis of bulk RNA sequencing data from SPNs, NETs, and normal pancreas, followed by experimental validation. This analysis revealed an increased accumulation of peroxisomes in SPNs. Moreover, we observed significant upregulation of the peroxisome marker ABCD1 in both primary and metastatic SPN samples compared with normal pancreas and NETs. To further investigate the potential utility of ABCD1 as a diagnostic marker for SPN via immunohistochemistry staining, we conducted verification in a large-scale patient cohort with pancreatic tumors, including 127 SPN (111 primary, 16 metastatic samples), 108 NET (98 nonfunctional pancreatic neuroendocrine tumor, NF-NET, and 10 functional pancreatic neuroendocrine tumor, F-NET), 9 acinar cell carcinoma (ACC), 3 pancreatoblastoma (PB), 54 pancreatic ductal adenocarcinoma (PDAC), 20 pancreatic serous cystadenoma (SCA), 19 pancreatic mucinous cystadenoma (MCA), 12 pancreatic ductal intraepithelial neoplasia (PanIN) and 5 intraductal papillary mucinous neoplasm (IPMN) samples. Our results indicate that ABCD1 holds promise as an easily applicable diagnostic marker with exceptional efficacy (AUC=0.999, sensitivity=99.10%, specificity=100%) for differentiating SPN from NET and other pancreatic neoplasms through immunohistochemical staining.

Magnetic resonance imaging short protocols for intraductal papillary mucinous neoplasm (IPMN) surveillance: The time has come

Background/ObjectivesTo analyze the diagnostic performance of three short magnetic resonance imaging (MRI) protocols for the follow-up of pancratic intraductal papillary mucinous neoplasms (IPMN). MethodsFollow-up MRI examinations of 287 patients with IPMN performed in two centers were retrospectively retrieved. Four MRI protocols were identified as follows: T1-weighted (T1w), T2-weighted (T2w), and MRCP sequences (protocol 1); T1w, T2w, MRCP, and diffusion-weighted (DWI) sequences (protocol 2); T1w, T2w, MRCP, and post-contrast T1w-sequences (protocol 3); and a comprehensive protocol including all previous sequences (protocol 4). Three radiologists with different experience in abdominal imaging expressed their opinion upon the optimal patient's management upon the evaluation of each protocol. Intra-and inter-observer agreement and concordance with the clinical decision expressed by a pancreatic surgeon were calculated with Cohen's kappa test. Results223 patients were included (66±10 years; 92 men, 131 women). 143 patients had branch-duct-IPMNs, 25 main-duct-IPMNs and 55 mixed-type-IPMNs. 79 patients underwent surgery, resulting in 52 high-grade dysplasia (HGD) and 27 low-grade dysplasia (LGD). Concordance for the expert reader between protocols 1, 2 and 3 and the actual clinical decision were 0.63, 0.72, and 0.74 respectively (95% CI, 0.53–0.73, 0.63–0.81, and 0.65–0.83). Inter-observer agreement between reader 1 and reader 2, reader 1 and reader 3, and reader 2 and reader 3 were: 0.71, 0.50, and 0.75 for protocol 1 (95% CI, 0.63–0.81, 0.40–0.60, and 0.66–0.84);0.68, 0.54, and 0.84 for protocol 2 (95% CI, 0.59–0.77, 0.44–0.64, and 0.76–0.91); and 0.77, 0.65, and 0.86 for protocol 3 (95% CI, 0.69–0.86, 0.55–0.74, and 0.80–0.93). ConclusionsShort MRI protocol is suitable for IPMN surveillance.

Neoplasias quísticas hepatobiliares productoras de mucina: claves diagnósticas para radiólogos

Mucin-producing cystic hepatobiliary neoplasms are rare neoplasms which include mucinous cystic neoplasms of the liver and intraductal papillary mucinous neoplasms of the bile duct.Mucinous cystic neoplasms of the liver are characterised by the presence of ovarian-like stroma, and are usually benign. They present as large, multiloculated, cystic masses without biliary communication and are more common among middle-aged women.Intraductal papillary mucinous neoplasms of the bile duct are premalignant lesions originating in the bile duct and presenting with biliary communication. There are 3 growth patterns: cystic, duct-ectatic and mass-forming. They tend to appear between the ages of 50 and 70, with no gender predilection. There is a high probability of malignancy, so segment-oriented hepatic resection is the treatment of choice.Both entities have overlapping and distinctive features, and it is important for the radiologist to be aware of these and be able to distinguish between them, as they have different prognoses and require different management approaches.

The diagnostic value of abbreviated MRI protocol in the surveillance of Branch-Duct intraductal papillary mucinous neoplasm

PurposeTo assess the diagnostic value of abbreviated protocol (AP) MRI to detect the degeneration signs in branch-duct intraductal papillary mucinous neoplasms (BD-IPMNs) in patients undergoing a routine MRI follow-up. MethodsThis dual-center retrospective study include patients with BD-IPMN diagnosed on initial comprehensive protocol (CP) MRI who underwent routine MRI follow-up. CP included axial and coronal T2-weighted images (T2WI), axial T1-weighted images (T1WI) before and after contrast administration, 3D MR cholangiopancreatography (MRCP) and diffusion-weighted images (DWI). Two APs, eliminating dynamic sequences ± DWI, were extracted from CP. Two radiologists evaluated the APs separately for IPMN degeneration signs according to Fukuoka criteria and compared the results to the follow-up CP. In patients who underwent EUS, imaging findings were correlated with pathological results. Per-patient and per-lesion sensitivity, specificity, PPV, NPV, and accuracy of APs were calculated. Additionally, the acquisition time for different protocols was calculated. ResultsOne hundred-fourteen patients (56.1 % women, median age: 71 years) with 256 lesions were included. Degeneration signs were observed in 24.6 % and 12.1 % per-patient and per-lesion, respectively. Regarding APs, the per patient sensitivity, specificity, PPV, NPV, and accuracy in the detection of the degeneration signs were 100 %, 93.5 %, 83.3 %, 100 %, and 95.1 %, respectively. No additional role for DWI was detected. AP without DWI economized nearly half of CP acquisition time (388 versus 663 s, respectively). ConclusionAP can confidently replace CP for BD-IPMN follow-up with high sensitivity and PPV while offering benefits such as patient comfort, improved MRI accessibility, and reduced dedicated time for image analysis. DWI necessitates special consideration. Clinical Relevance StatementOur data suggest that APs safely detect all degeneration signs of IPMN. While there is an overestimation of mural nodules due to the lack of contrast injection, this occurs in a negligible number of patients.

High-resolution Optical Pancreatoscopy for Recurrent Main Duct Intraductal Papillary Mucinous Neoplasms

High-resolution Optical Pancreatoscopy for Recurrent Main Duct Intraductal Papillary Mucinous Neoplasms

Robotic Ultrasound-Guided Central Pancreatectomy with Main Pancreatic Duct Endoscopy Evaluation for High-Risk, Mixed-Type Intraductal Papillary Mucinous Neoplasm.

Central pancreatectomy (CP) is a parenchymal-sparing technique indicated for the resection of selected lesions of the neck or proximal body of the pancreas.1,2 The risk of postoperative complications is theoretically doubled because the surgeon has to manage two cut surfaces of the pancreas. The video shows a fully robotic CP to treat a 62-year-old male patient with a mixed-type intraductal papillary mucinous neoplasm (IPMN) of the pancreatic neck, using ultrasound (US) and Wirsung endoscopic evaluation to guide the pancreatic resection and ensure optimal resection margins. A US-guided robotic CP was carried out, and an intraoperative endoscopic evaluation of the MPD was performed to determine the distal transection level. A transmesocolic, end-to-side, robot-sewn Wirsung-jejunostomy with internal MPD stenting was then created. The procedure was completed with a side-to-side jejunojejunostomy. The operative time was 290min, with negligible blood loss. During the postoperative course, the patient experienced bleeding from a branch of the gastroduodenal artery with subsequent fluid collection, which was successfully treated with angioembolization and percutaneous drainage. He was discharged home on postoperative day 22. Final pathology revealed a non-invasive IPMN with low-grade dysplasia and free surgical margins. At 12 months of follow-up, the patient was doing well, with no evidence of local recurrence and endocrine or exocrine pancreatic insufficiency. The combination of robotic surgery with intraoperative US and Wirsungoscopy may offer distinct technical advantages for challenging pancreatectomies that follow the principles of parenchymal-sparing surgery.

Identification of spatially-resolved markers of malignant transformation in Intraductal Papillary Mucinous Neoplasms

The existing Intraductal Papillary Mucinous Neoplasm (IPMN) risk stratification relies on clinical and histological factors, resulting in inaccuracies and leading to suboptimal treatment. This is due to the lack of appropriate molecular markers that can guide patients toward the best therapeutic options. Here, we assess and confirm subtype-specific markers for IPMN across two independent cohorts of patients using two Spatial Transcriptomics (ST) technologies. Specifically, we identify HOXB3 and ZNF117 as markers for Low-Grade Dysplasia, SPDEF and gastric neck cell markers in borderline cases, and NKX6-2 and gastric isthmus cell markers in High-Grade-Dysplasia Gastric IPMN, highlighting the role of TNFα and MYC activation in IPMN progression and the role of NKX6-2 in the specific Gastric IPMN progression. In conclusion, our work provides a step forward in understanding the gene expression landscapes of IPMN and the critical transcriptional networks related to PDAC progression.

Abstract 446: Integrated spatial transcriptomics and lipidomics analyses of intraductal papillary mucinous neoplasm identifies enrichment of long chain sulfatide as an early metabolic alteration

Abstract Purpose: To define the metabolic alterations associated with malignant progression of intraductal papillary mucinous neoplasm (IPMN). Experimental Procedures: Matrix-assisted laser desorption/ionization (MALDI)-mass spectrometry (MS) was conducted for spatial characterization of lipid profiles on frozen tissue sections from resected human IPMN patients. The specimen set consisted of either low-grade dysplasia (LG) (n=15), high-grade (HG) dysplasia (n=4), or with an associated pancreatic ductal adenocarcinoma (PDAC) (n=4) as well as 15 PDAC tissues. Utilizing serial sections to the same human IPMN cases analyzed with MALDI-MS imaging, we used the Visium Spatial Gene Expression technology platform to characterize the spatiomolecular underpinnings of LG and HG IPMN. H&amp;E images of the same tissue section used for the Visium workflow, were used to annotate the spots in the dataset covering the epithelial lining of the IPMN lesions (“epilesional” areas) and the spots covering the adjacent microenvironment surrounding the lesion (“perilesiopecific” area). Findings were compared with lipidomic analyses of cystic fluid from 89 IPMN patients. The anti-cancer efficacy of UGT8-IN-1, a selective small molecule inhibitor of ceramide galactosyltransferase (CGT, also known as UGT8), was assessed in vitro and in mutant Kras;Gnas allografts. Results: MALDI/MS-based spatial imaging of human resected IPMN tissues and pancreata from a mutant Kras;Gnas mouse model of IPMN revealed long-chain hydroxylated sulfatides, particularly the C24:0(OH) and C24:1(OH) species, to be selectively enriched in the IPMN and PDAC neoplastic epithelium. Visium spatial transcriptomics data confirmed that the cognate transcripts engaged in sulfatide biosynthesis, including UGT8, Gal3St1, and FA2H, were co-localized with areas of sulfatide enrichment. Lipidomic analyses of cystic fluid from 89 patients with IPMN identified several sulfatide species to be significantly elevated in patients with IPMN/PDAC compared to those with low-grade IPMN. Inhibition of sulfatide metabolism via UGT8-IN-1 reduced viability of Kras;Gnas murine cell lines in vitro and attenuated tumor growth in an allograft IPMN model. UGT8-IN-1 treatment resulted in reduced levels of several sulfatide species, accompanied by a concomitant increase in a subset of quantified sulfatides precursor ceramides, accumulation of mitochondrial mass and reactive oxygen species and time-dependent increases in autophagy/mitophagy markers p62/SQSTM1 and LC-3B, suggesting impaired mitophagy. Conclusion: Enhanced sulfatide metabolism is an early alteration in cystic pre-cancerous lesions of the pancreas that persists through invasive neoplasia. Targeting sulfatide biosynthesis might represent an actionable vulnerability for cancer interception. Citation Format: Yihui Chen, Marta Sans, Fredrik Thege, Rongzhang Dou, Jimin Min, Michele Yip-Schneider, Jianjun Zhang, Ranran Wu, Ehsan Irajizad, Yuki Makino, Kimal Rajapakshe, Mark Hurd, Ricardo León-Letelier, Jody Vykoukal, Jennifer Dennison, Kim-Anh Do, Robert Wolff, Paola Guerrero, Michael Kim, Max Schmidt, Anirban Maitra, Samir Hanash, Johannes Fahrmann. Integrated spatial transcriptomics and lipidomics analyses of intraductal papillary mucinous neoplasm identifies enrichment of long chain sulfatide as an early metabolic alteration [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 446.

Abstract 6092: Three-dimensional multi-omic analysis of early invasion of human pancreatic ductal adenocarcinoma from IPMN

Abstract Background: Pancreatic ductal adenocarcinoma (PDAC) is a deadly cancer, with only 11% of patients surviving beyond 5 years. Intraductal papillary mucinous neoplasm (IPMN), a precancerous lesion and the most common type of neoplastic pancreatic cyst, presents a critical opportunity for cancer interception, but the drivers of malignant progression in IPMN are still largely unknown. Although the immunosuppressive microenvironment of PDAC has been well characterized, the timing of the development of these immune alterations in IPMNs is not well studied and could provide a rational foundation for cancer immuno-prevention. Moreover, the inception of invasive PDAC and its spread into the microenvironment from IPMN is complex, multifactorial, and, due to its unique anatomy, challenging to analyze with traditional 2-dimensional visualization. We sought to capture the precise point of transition from IPMN to invasive carcinoma utilizing CODA, a supervised deep learning tool for three-dimensional (3D) reconstruction of serially sectioned human tissue, in order to quantitatively assess the molecular and cellular alterations associated with malignant progression. Method: Formalin-fixed paraffin-embedded (FFPE) tissue blocks with PDAC arising from IPMN were serially sectioned, every third slide was stained with H&amp;E, and digitized at 20x magnification. Following pathologist-guided annotations on a subset of H&amp;E slides, CODA generated 3D models of each tissue block, including automated annotation of 9 pancreatic tissue components. Using these annotations, we identified the transition from IPMN to invasive carcinoma in each sample and selected regions for multi-omic profiling based on quantitative features of the cellular microenvironment. Multi-omic profiling of IPMN, transition zone, and PDAC included laser capture microdissection followed by whole exome sequencing to identify somatic DNA alterations, as well as spatial transcriptomics to identify alterations in gene expression in neoplastic cells and spatial proteomics to identify cellular alterations in the surrounding microenvironment. Results: CODA generated accurate annotation on all the H&amp;E slides from each case and robustly identified regions of interest for multi-omic profiling. Spatial proteomic profiling using imaging mass cytometry revealed a decrease in T cell density as IPMNs transition into PDAC. Sub- clustering of the T cell compartment identified decreases in multiple T cell subsets, including activated cytotoxic T cells and helper T cells, in the transition zone compared to IPMN. Conclusion: In this study, we integrated multi-omic profiling with CODA-generated high-resolution 3D tissue maps to identify molecular and cellular drivers of malignant progression in human PDAC. Citation Format: Shalini Datta, Sarah M. Shin, Jessie Kanacharoen, Michael Johannes Pflüger, Katsuya Hirose, André Forjaz, Sarah Graham, Pei-Hsun Wu, Ralph H. Hruban, Denis Wirtz, Won Jin Ho, Ashley L. Kiemen, Laura D. Wood. Three-dimensional multi-omic analysis of early invasion of human pancreatic ductal adenocarcinoma from IPMN [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 6092.

Long-term Outcomes following Resection of Adenocarcinoma Arising from Intraductal Papillary Mucinous Neoplasm (A-IPMN) versus Pancreatic Ductal Adenocarcinoma (PDAC): A Propensity-score Matched Analysis.

The aim of the present study was to compare long-term post-resection oncological outcomes between A-IPMN and PDAC. Knowledge of long term oncological outcomes (e.g recurrence and survival data) comparing between adenocarcinoma arising from intraductal papillary mucinous neoplasms (A-IPMN) and pancreatic ductal adenocarcinoma (PDAC) is scarce. Patients undergoing pancreatic resection (2010-2020) for A-IPMN were identified retrospectively from 18 academic pancreatic centres and compared with PDAC patients from the same time-period. Propensity-score matching (PSM) was performed and survival and recurrence were compared between A-IPMN and PDAC. 459 A-IPMN patients (median age,70; M:F,250:209) were compared with 476 PDAC patients (median age,69; M:F,262:214). A-IPMN patients had lower T-stage, lymphovascular invasion (51.4%vs. 75.6%), perineural invasion (55.8%vs. 71.2%), lymph node positivity (47.3vs. 72.3%) and R1 resection (38.6%vs. 56.3%) compared to PDAC(P<0.001). The median survival and time-to-recurrence for A-IPMN versus PDAC were 39.0 versus19.5months (P<0.001) and 33.1 versus 14.8months (P<0.001), respectively (median follow-up,78 vs.73 months). Ten-year overall survival for A-IPMN was 34.6%(27/78) and PDAC was 9%(6/67). A-IPMN had higher rates of peritoneal (23.0 vs. 9.1%, P<0.001) and lung recurrence (27.8% vs. 15.6%, P<0.001) but lower rates of locoregional recurrence (39.7% vs. 57.8%; P<0.001). Matched analysis demonstrated inferior overall survival (P=0.005), inferior disease-free survival (P=0.003) and higher locoregional recurrence (P<0.001) in PDAC compared to A-IPMN but no significant difference in systemic recurrence rates (P=0.695). PDACs have inferior survival and higher recurrence rates compared to A-IPMN in matched cohorts. Locoregional recurrence is higher in PDAC but systemic recurrence rates are comparable and constituted by their own distinctive site-specific recurrence patterns.

Abstract 6167: Spatial transcriptomic analysis identifies pancreatic cancer cell surface markers for imaging and therapy

Abstract Pancreatic cysts and precancer lesions have been reported in up to 50% of adults; however, few of the precancer lesions develop into aggressive pancreatic ductal adenocarcinoma (PDAC). Strategies for the differentiation of precancers and PDAC are needed. Recently proposed molecular imaging targets to accomplish this goal include integrin αvβ6 and fibroblast activation protein (FAP). To discover and quantitatively evaluate potential imaging and therapeutic targets, we performed Visium spatial transcriptomic (ST) sequencing on human surgical sections of normal tissue adjacent to precancers, intraductal papillary mucinous neoplasms and PDAC. All human tissues were collected in accordance with the Stanford Institutional Review Board. The resulting data were correlated with immunohistochemistry (IHC) and combined with analysis with publicly available spatial and single cell PDAC datasets to create a quantitative PDAC cancer surfaceome score. Pseudotime and receiver operating characteristic (ROC) analyses were also performed. We found that clusters with high cancer surfacesome scores were spatially correlated with a cellular morphology consistent with cancer. In the cancer cluster, the expression of surface markers CLDN4, GPRC5A, TSPAN8, and CEACAM5 was enhanced more than 13-fold compared with the normal pancreas, while FAP and ITGB6 were differentially expressed by less than 4-fold. Within cancer clusters, the fraction of spots overexpressing CLDN4, S100P, ITGB6, MUC5AC, TFF1, CEACAM5, and FAP was 88%, 87%, 78%, 66%, 59%, 47%, and 38%, respectively. The Pearson’s correlation across space and expression intensity between CLDN4, S100P, GPRC5A, TSPAN8, MUC1 and TFF1 was greater than 0.6 for all combinations. The correlation of mRNA encoding ITGB6 and FAP with cancer surfaceome markers was smaller, e.g. 0.37 and 0.01 versus S100P, respectively. The area under the curve (AUC) for the differentiation of PDAC from normal or precancerous tissue for CLDN4, S100P, MUC5AC, TFF1, CEACAM5, and TSPAN8 was 0.9, 0.5, 0.3, 0.5, 0.8, and 0.4, respectively. From pseudotime trajectory analysis, we found that MUC5AC and TFF1 increased at a precancerous pseudotime whereas CLDN4 increased in time and space in spots corresponding to a PDAC-specific surfaceome score. This work demonstrates the feasibility of using spatial transcriptomics and IHC in human pancreatic cancer samples to discover and compare the expression of cell surface markers that can be employed in imaging and therapeutic protocols. Citation Format: James Wang, Aris J. Kare, Martn K. Schneider, Jai Woong Seo, Andrei Iagaru, Gregory W. Charville, Walter G. Park, Katherine W. Ferrara. Spatial transcriptomic analysis identifies pancreatic cancer cell surface markers for imaging and therapy [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 6167.

Abstract 1588: Identification of new signaling pathways between fibroblasts &amp; tumor cells in pancreatic cancer

Abstract We explore the unstudied role of nanoparticles (NPs), recently discovered secreted non-vesicular nanoparticles, in signaling between pre-cancer associated fibroblasts (preCAF), CAFs, and tumor cells. We generated two novel primary lines preCAF PFUM1 from a patient with high-grade intraductal papillary mucinous neoplasms and CAF FUM2 from a patient with pancreatic ductal adenocarcinoma, all tests performed between passages 2 and 3, fibroblast purity validated by RT-PCR and ACTA2 immunofluorescence. Small extracellular vesicles (sEVs), exomeres, and supermeres (the two main forms of NPs) were isolated by the ultracentrifugation method from PF-UM1 and F-UM2 with n=2-3 experiments. To validate the isolation, we used nanoparticle tracking, electron, and fluid-phase atomic force microscopy. Proteins were quantified by BCA assay. Liquid chromatography-mass spectrometry characterized the cargo from each fraction. Human cancer lines MIAPACA2 and SU8686 were treated with 10 μg of each fraction and cell proliferation was tested by phase-contrast images (Cytation 5), analyzed by Ilastik-based 1.4.0 machine-learning. We performed fluorescent Ki-67 and vimentin staining and quantified in QuPath 0.4.3. Non-parametric statistics were performed in Prism GraphPad. NPs constitute the major fraction of small particles released by fibroblasts, containing 80.5% (PFUM1) and 77.5% (FUM2) of the protein load by quantification. Mass spectrometry reveals enrichment of growth factors, epithelial-to-mesenchymal (EMT) transition, and metabolism-associated proteins in the NPs compared to sEVs. At 72 hours, cell proliferation for Su8686 reveals a proliferative effect for all fractions from both PFUM1 and FUM2 (19-63% increase compared to controls, p=0.049 to &amp;lt;0.0001). For MIAPACA2, only supermeres from PFUM1 and FUM2 consistently increased proliferation (9.5-35% increase, p=0.0051 to &amp;lt;0.0001). Ki-67 expression in MIAPACA2, increased by 9.6-23.0% following treatment by NPs (all p&amp;lt;0.0001) and by 2.9-9.2% with sEVs (p=0.011 to &amp;lt;0.0001). EMT was estimated by vimentin in MIAPACA2, as all preCAF fractions from PFUM1 reduced vimentin expression (p&amp;lt;0.001), while CAF FUM2 NPs increased vimentin expression (p&amp;lt;0.0001) while sEVs had no effect (p=0.075). In conclusion, the majority of pancreatic tumor-associated fibroblast small secretome is composed of NPs, exhibiting significant functional pro-tumoral effects. Citation Format: Ayman Al Shoukari, Maelle Batardiere, Nooshin Movahed, Camille beaussier, Jumanah Baig, Melissa gonzalez, Patricia Moraille, Eric Bonneil, Louise Rousseau, Simon turcotte, Kathleen Delgiorno, Marcus Tan, Anna Means, Elham Dianati Ajibisheh, Quoc-huy Trinh. Identification of new signaling pathways between fibroblasts &amp; tumor cells in pancreatic cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 1588.

Endoscopic Ultrasound-Guided Needle-Based Confocal Endomicroscopy as a Diagnostic Imaging Biomarker for Intraductal Papillary Mucinous Neoplasms.

Pancreatic cancer is on track to become the second leading cause of cancer-related deaths by 2030, yet there is a lack of accurate diagnostic tests for early detection. Intraductal papillary mucinous neoplasms (IPMNs) are precursors to pancreatic cancer and are increasingly being detected. Despite the development and refinement of multiple guidelines, diagnosing high-grade dysplasia or cancer in IPMNs using clinical, radiologic, endosonographic, and cyst fluid features still falls short in terms of accuracy, leading to both under- and overtreatment. EUS-guided needle-based confocal laser endomicroscopy (nCLE) is a novel technology that allows real-time optical biopsies of pancreatic cystic lesions. Emerging data has demonstrated that EUS-nCLE can diagnose and risk stratify IPMNs more accurately than conventional diagnostic tools. Implementing EUS-nCLE in clinical practice can potentially improve early diagnosis of pancreatic cancer, reduce unnecessary surgeries of IPMNs with low-grade dysplasia, and advance the field of digital pathomics. In this review, we summarize the current evidence that supports using EUS-nCLE as a diagnostic imaging biomarker for diagnosing IPMNs and for risk stratifying their degree of neoplasia. Moreover, we will present emerging data on the role of adding artificial intelligence (AI) algorithms to nCLE and integrating novel fluid biomarkers into nCLE.

Intraductal Papillary Mucinous Neoplasm Surveillance Leads to Early Diagnosis and Better Outcomes of Concomitant Cancer.

To examine whether long-term surveillance of intraductal papillary mucinous neoplasms (IPMNs) leads to early diagnosis and better clinical outcomes of pancreatic ductal adenocarcinomas (PDACs) developing concomitantly with IPMNs. Long-term image-based surveillance is recommended for patients with low-risk IPMNs. However, it is unknown whether the surveillance can improve surgical and survival outcomes of patients with concomitant PDACs. Using a prospective single-institutional cohort of 4,620 patients with pancreatic cysts including 3,638 IPMN patients, we identified 63 patients who developed concomitant PDAC during long-term surveillance. We compared overall survival (OS) of 46 cases with concomitant PDAC to that of 460 matched cases diagnosed with non-IPMN-associated PDAC at the same institution. Multivariable hazard ratios and 95% confidence intervals (CIs) for overall mortality were computed using the Cox regression model with adjustment for potential confounders. Concomitant PDACs were identified at an earlier cancer stage compared to non-IPMN-associated PDACs with 67% and 38% cases identified at stage 2 or earlier, respectively (P<0.001) and 57% and 21% cases with R0 resection, respectively (P<0.001). Compared to non-IPMN-associated PDACs, concomitant PDACs were associated with longer OS (P=0.034) with a multivariable hazard ratio of 0.61 (95% CI, 0.39-0.96). The 5-year survival rate of patients with concomitant PDAC was higher compared to patients with non-IPMN-associated PDAC (34% vs. 18%, respectively; P=0.018). The surveillance for patients with IPMNs was associated with early identification of concomitant PDACs and longer survival of patients diagnosed with this malignancy.

O77: Invasive intraductal oncocytic papillary neoplasms (IOPN) and adenocarcinomas arising from Intraductal papillary mucinous neoplasms (IPMN): adjuvant chemotherapy, patterns of recurrence and survival

Abstract Introduction Invasive intraductal oncocytic papillary neoplasms (IOPNs) are extremely rare and are increasingly being recognised as their own entity, distinct from intraductal papilliary mucinous neoplasism subtypes (IPMN). Their clinicopathologic behaviour, recurrence patterns, response to adjuvant chemotherapy and long-term survival outcomes are unknown compared to adenocarcinomas arising from IPMN but were investigated in the present study. Methods Patients undergoing pancreatic resection between 2010-2020 for invasive IOPNs and adenocarcinoma arising from IPMNs were identified retrospectively from 18 academic pancreatic centers worldwide. Survival analyses were conducted to compare outcome measures between IOPNs and IPMN precursor epithelial subtypes and invasive components. Results Of the 459 patients with invasive IOPN/IPMNs, 20 patients had an invasive IOPN (median age,69; male,n=11), the majority of which were in the pancreatic head (75%) and underwent either a Whipples procedure (40%) or PPPD (35%). After a median follow-up of 6 years, 45% of invasive IOPNs developed recurrence (1-year,30.0%; 5-year,69.2%) and 40% survived follow-up (2-year survival 55.0%, 5-year survival, 30.8%). Recurrence rates and survival of invasive IOPNs were higher than colloid IPMNs (n=64) (p=0.031 and p=0.007) and comparable with ductal IPMNs (n=331) as well as gastric (n=54) and pancreatobiliary (n=111) IPMN subtypes. Invasive IOPN had significantly lower cancer-specific survival compared to colloid carcinomas (p&amp;lt;0.001). Adjuvant chemotherapy did not improve rates of recurrence in invasive IOPN and IPMN subtypes (p&amp;gt;0.05). Conclusions Invasive IOPNs are more aggressive than previously suspected and should be regarded as their own entity. Adjuvant chemotherapy does not reduce rates of recurrence regardless of neoplasm type.

Aberrant Glycosylation in Pancreatic Ductal Adenocarcinoma 3D Organoids Is Mediated by KRAS Mutations.

Aberrant glycosylation in tumor cells is a hallmark during carcinogenesis. KRAS gene mutations are the most well-known oncogenic abnormalities but their association with glycan alterations in pancreatic ductal adenocarcinoma (PDAC) is largely unknown. We employed patient-derived 3D organoids to culture pure live PDAC cells, excluding contamination by fibroblasts and immune cells, to gasp the comprehensive cancer cell surface glycan expression profile using lectin microarray and transcriptomic analyses. Surgical specimens from 24 PDAC patients were digested and embedded into a 3D culture system. Surface-bound glycans of 3D organoids were analyzed by high-density, 96-lectin microarrays. KRAS mutation status and expression of various glycosyltransferases were analyzed by RNA-seq. We successfully established 16 3D organoids: 14 PDAC, 1 intraductal papillary mucinous neoplasm (IPMN), and 1 normal pancreatic duct. KRAS was mutated in 13 (7 G12V, 5 G12D, 1 Q61L) and wild in 3 organoids (1 normal duct, 1 IPMN, 1 PDAC). Lectin reactivity of AAL (Aleuria aurantia) and AOL (Aspergillus oryzae) with binding activity to α1-3 fucose was higher in organoids with KRAS mutants than those with KRAS wild-type. FUT6 (α1-3fucosyltransferase 6) and FUT3 (α1-3/4 fucosyltransferase 3) expression was also higher in KRAS mutants than wild-type. Meanwhile, mannose-binding lectin (rRSL [Ralstonia solanacearum] and rBC2LA [Burkholderia cenocepacia]) signals were higher while those of galactose-binding lectins (rGal3C and rCGL2) were lower in the KRAS mutants. We demonstrated here that PDAC 3D-cultured organoids with KRAS mutations were dominantly covered in increased fucosylated glycans, pointing towards novel treatment targets and/or tumor markers.

Identification of breath volatile organic compounds to distinguish pancreatic adenocarcinoma, pancreatic cystic neoplasm, and patients without pancreatic lesions.

Volatile organic compounds (VOCs) are a promising potential biomarker that may be able to identify the presence of cancers. To identify exhaled breath VOCs that distinguish pancreatic ductal adenocarcinoma (PDAC) from intraductal papillary mucinous neoplasm (IPMN) and healthy volunteers. We collected exhaled breath from histologically proven PDAC patients, radiological diagnosis IPMN, and healthy volunteers using the ReCIVA® device between 10/2021-11/2022. VOCs were identified by thermal desorption-gas chromatography/field-asymmetric ion mobility spectrometry and compared between groups. A total of 156 participants (44% male, mean age 62.6 ± 10.6) were enrolled (54 PDAC, 42 IPMN, and 60 controls). Among the nine VOCs identified, two VOCs that showed differences between groups were dimethyl sulfide [0.73 vs 0.74 vs 0.94 arbitrary units (AU), respectively; P = 0.008] and acetone dimers (3.95 vs 4.49 vs 5.19 AU, respectively; P < 0.001). After adjusting for the imbalance parameters, PDAC showed higher dimethyl sulfide levels than the control and IPMN groups, with adjusted odds ratio (aOR) of 6.98 (95%CI: 1.15-42.17) and 4.56 (1.03-20.20), respectively (P < 0.05 both). Acetone dimer levels were also higher in PDAC compared to controls and IPMN (aOR: 5.12 (1.80-14.57) and aOR: 3.35 (1.47-7.63), respectively (P < 0.05 both). Acetone dimer, but not dimethyl sulfide, performed better than CA19-9 in PDAC diagnosis (AUROC 0.910 vs 0.796). The AUROC of acetone dimer increased to 0.936 when combined with CA19-9, which was better than CA19-9 alone (P < 0.05). Dimethyl sulfide and acetone dimer are VOCs that potentially distinguish PDAC from IPMN and healthy participants. Additional prospective studies are required to validate these findings.