Dynamic evolution of fibroblasts revealed by single cell RNA sequencing of human pancreatic cancer.

Cancer progression and response to therapy are inextricably reliant on the co-evolution of a supportive tissue microenvironment. This is particularly evident in pancreatic ductal adenocarcinoma (PDAC), a tumor type characterized by expansive and heterogeneous stroma. Herein, we employed single cell RNAseq and spatial transcriptomics of normal, inflamed, and malignant pancreatic tissues to contextualize stromal dynamics associated with disease and treatment status, identifying temporal and spatial trajectories of fibroblast differentiation. Using analytical tools to infer cellular communication, together with a newly developed assay to annotate genomic alterations in cancer cells, we additionally explored the complex intercellular networks underlying tissue circuitry, highlighting a fibroblast-centric interactome that grows in strength and complexity in the context of malignant transformation. Our study yields new insights on the stromal remodeling events favoring the development of a tumor-supportive microenvironment and provides a powerful resource for the exploration of novel points of therapeutic intervention in PDAC.

Impact of neoadjuvant chemoradiotherapy on pathologic response in pancreatic ductal adenocarcinoma: A systematic review and meta-analysis.

BACKGROUND: The impact of chemoradiotherapy on pathologic response, resection margin, and survival benefit is still debated. The aim of this study was to compare the rate of pathologic complete response (pCR) in surgical resection following neoadjuvant chemotherapy vs. chemoradiotherapy, and secondarily, to compare the rate of R0 resection and Overall Survival (OS). METHODS: A systematic review on MEDLINE/PubMed, Embase, Cochrane, Web of Science and Google Scholar was conducted for studies published between 2012 and 2024 (PROSPERO CRD42022341467). All studies reporting clinical outcomes of patients with Pancreatic ductal adenocarcinoma (PDAC) following neoadjuvant therapy were considered eligible for inclusion. A meta-analysis comparing the rate of pCR, R0 resection rate, and 3-year OS following Chemotherapy vs chemoradiotherapy in patients was performed. The overall quality of evidence was evaluated using a GRADE approach. RESULTS: Out of 5194 potentially relevant studies, 29 studies were considered eligible for full-text assessment, and 11 studies were included in the systematic review and in the meta-analysis. Of these, five were retrospective single-center, five retrospective multi-center studies, and one was a phase II multi-center RCT. Overall, 1830 Chemotherapy patients and 2299 Chemoradiotherapy patients were included in the meta-analysis. A statistically significant increased rate of pCR and R0 resections were found in chemoradiotherapy patients (OR 3.58, 95 % CI 2.47-5.18, p ≤ 0.00001) (OR 1.49, 95 % CI 1.17-1.90, p = 0.001), whereas 3-year OS (OR 1.07, 95 % CI 0.84-1.36, p = 0.6) did not differ significantly. CONCLUSIONS: Chemoradiotherapy may have a positive impact on pathologic response and R0 resection rate, whereas a survival benefit was not reported.

Clinical and Financial Validation of the International Study Group for Pancreatic Surgery (ISGPS) Definition of Post-Pancreatectomy Acute Pancreatitis (PPAP): International Multicenter Prospective Study.

OBJECTIVE: To validate the ISGPS definition and grading system of PPAP after pancreatoduodenectomy (PD). SUMMARY BACKGROUND DATA: In 2022, the International Study Group for Pancreatic Surgery (ISGPS) defined post-pancreatectomy acute pancreatitis (PPAP) and recommended a prospective validation of its diagnostic criteria and grading system. METHODS: This was a prospective, international, multicenter study including patients undergoing PD at 17 referral pancreatic centers across Europe, Asia, Oceania, and the United States. PPAP diagnosis required the following three parameters: (1) postoperative serum hyperamylasemia /hyperlipasemia (POH) persisting on postoperative days 1 and 2, (2) radiologic alterations consistent with PPAP, and (3) a clinically relevant deterioration in the patient's condition. To validate the grading system, clinical and economic parameters were analyzed across all grades. RESULTS: Among 2902 patients undergoing PD, 7.5% (n=218) developed PPAP (6.3% grade B and 1.2% grade C). POH occurred in 24.1% of patients. Hospital stay was associated with PPAP grades (No POH/PPAP 10 days (IQR 7-17) days, grade B 22 days (IQR 15-34) days, and grade C 43 days (IQR 27-54) days; P<0.001), as well as intensive care unit admission (No POH/PPAP 5.4%, grade B 12.6%, grade C 82.9%; P<0.010), and hospital readmission rates (No POH/PPAP 7.3%, grade B 16.1%, grade C 18.5%; P<0.05). Costs of grade B and C PPAP were 2 and 11 times greater than uncomplicated clinical course, resp. (P<0.001). CONCLUSIONS: This first prospective, international validation study of the ISGPS definition and grading system for PPAP highlighted the relevant clinical and financial implications of this condition. These results stress the importance of routine screening for PPAP in patients undergoing PD.

HCC spatial transcriptomic profiling reveals significant and potentially targetable cancer-endothelial interactions.

BACKGROUND: HCC is a highly vascular tumor, and many effective drug regimens target the tumor blood vessels. Prior bulk HCC subtyping data used bulk transcriptomes, which contained a mixture of parenchymal and stromal contributions. METHODS: We utilized computational deconvolution and cell-cell interaction analyses to cell type-specific (tumor-enriched and vessel-enriched) spatial transcriptomic data collected from 41 resected HCC tissue specimens. RESULTS: We report that the prior Hoshida bulk transcriptional subtyping schema is driven largely by an endothelial fraction, show an alternative tumor-specific schema has potential prognostic value, and use spatially paired ligand-receptor analyses to identify known and novel (LGALS9 tumor-HAVCR2 vessel) signaling relationships that drive HCC biology in a subtype-specific and potentially targetable manner. CONCLUSIONS: Our study leverages spatial gene expression profiling technologies to dissect HCC heterogeneity and identify heterogeneous signaling relationships between cancer cells and their endothelial cells. Future validation and expansion of these findings may validate novel cancer-endothelial cell interactions and related drug targets.

Accuracy of Clinical Staging in Early-Stage Pancreatic Ductal Adenocarcinoma.

This study evaluates the accuracy of clinical staging in early-stage pancreatic ductal adenocarcinoma.

Interobserver Variability in the International Study Group for Pancreas Surgery (ISGPS)-Defined Complications After Pancreatoduodenectomy: An International Cross-Sectional Multicenter Study.

OBJECTIVE: To determine the interobserver variability for complications of pancreatoduodenectomy as defined by the International Study Group for Pancreatic Surgery (ISGPS) and others. SUMMARY BACKGROUND DATA: Good interobserver variability for the definitions of surgical complications is of major importance in comparing surgical outcomes between and within centers. However, data on interobserver variability for pancreatoduodenectomy-specific complications are lacking. METHODS: International cross-sectional multicenter study including 52 raters from 13 high-volume pancreatic centers in 8 countries on 3 continents. Per center, 4 experienced raters scored 30 randomly selected patients after pancreatoduodenectomy. In addition, all raters scored six standardized case vignettes. This variability and the 'within centers' variability were calculated for twofold scoring (no complication/grade A vs grade B/C) and threefold scoring (no complication/grade A vs grade B vs grade C) of postoperative pancreatic fistula (POPF), post-pancreatoduodenectomy hemorrhage (PPH), chyle leak (CL), bile leak (BL), and delayed gastric emptying (DGE). Interobserver variability is presented with Gwet's AC-1 measure for agreement. RESULTS: Overall, 390 patients after pancreatoduodenectomy were included. The overall agreement rate for the standardized cases vignettes for twofold scoring was 68% (95%-CI: 55%-81%, AC1 score: moderate agreement) and for threefold scoring 55% (49%-62%, AC1 score: fair agreement). The mean 'within centers' agreement for twofold scoring was 84% (80%-87%, AC1 score; substantial agreement). CONCLUSION: The interobserver variability for the ISGPS defined complications of pancreatoduodenectomy was too high even though the 'within centers' agreement was acceptable. Since these findings will decrease the quality and validity of clinical studies, ISGPS has started efforts aimed at reducing the interobserver variability.

Complexity and Experience Grading to Guide Patient Selection for Minimally-invasive Pancreatoduodenectomy: An ISGPS Consensus.

OBJECTIVE: The ISGPS aims to develop a universally accepted complexity and experience grading system to guide the safe implementation of robotic and laparoscopic minimally-invasive pancreatoduodenectomy (MIPD). BACKGROUND: Despite the perceived advantages of MIPD, its global adoption has been slow due to the inherent complexity of the procedure and challenges to acquiring surgical experience. Its wider adoption must be undertaken with an emphasis towards appropriate patient selection according to adequate surgeon and center experience. METHODS: The ISGPS developed a complexity and experience grading system to guide patient selection for MIPD based on an evidence-based review and a series of discussions. RESULTS: The ISGPS complexity and experience grading system for MIPD is subclassified into patient-related risk factors and provider experience-related variables. The patient-related risk factors include anatomical (main pancreatic and common bile duct diameters), tumor-specific (vascular contact), and conditional (obesity and previous complicated upper abdominal surgery/disease) factors, all incorporated in an A-B-C classification, graded as no, a single, and multiple risk factors. The surgeon and center experience-related variables include surgeon total MIPD experience (cut-offs 40 and 80) and center annual MIPD volume (cut-offs 10 and 30), all also incorporated in an A-B-C classification. CONCLUSION: This ISGPS complexity and experience grading system for robotic and laparoscopic MIPD may enable surgeons to optimally select patients after duly considering specific risk factors known to influence the complexity of the procedure. This grading system will likely allow for a thoughtful and stepwise implementation of MIPD and facilitate a fair comparison of outcome between centers and countries.

Generation of a biliary tract cancer cell line atlas reveals molecular subtypes and therapeutic targets.

Biliary tract cancers (BTCs) are a group of deadly malignancies encompassing intrahepatic and extrahepatic cholangiocarcinoma, gallbladder carcinoma, and ampullary carcinoma. Here, we present the integrative analysis of 63 BTC cell lines via multi-omics clustering and genome- scale CRISPR screens, providing a platform to illuminate BTC biology and inform therapeutic development. We identify dependencies broadly enriched in BTC compared to other cancers as well as dependencies selective to the anatomic subtypes. Notably, cholangiocarcinoma cell lines are stratified into distinct lineage subtypes based on biliary or dual biliary/hepatocyte marker signatures, associated with dependency on specific lineage survival factors. Transcriptional analysis of patient specimens demonstrates the prognostic significance of these lineage subtypes. Additionally, we delineate strategies to enhance targeted therapies or to overcome resistance in cell lines with key driver gene mutations. Furthermore, clustering based on dependencies and proteomics data elucidates unexpected functional relationships, including a BTC subgroup with partial squamous differentiation. Thus, this cell line atlas reveals potential therapeutic targets in molecularly defined BTCs, unveils biologically distinct disease subtypes, and offers a vital resource for BTC research.

Lymph Node Yield is Associated with Improved Overall Survival and Increased Time to Recurrence in Node-Negative Pancreatic Ductal Adenocarcinoma Following Neoadjuvant Therapy.

OBJECTIVE: To determine if lymph node yield (LNY) is associated with improved overall survival (OS) and time to recurrence (TTR) in patients with node-negative pancreatic ductal adenocarcinoma (PDAC) treated with neoadjuvant therapy (NAT). BACKGROUND: Lymph node yield has been associated with survival in solid gastrointestinal cancers, including PDAC. METHODS: Patients with pathological T stage I-III, node-negative (N0), PDAC treated with NAT followed by pancreatoduodenectomy were identified in the Massachusetts General Hospital (MGH) pancreatectomy database and the National Cancer Database (NCDB). A cutoff point of 22 nodes was identified in the NCDB using the point with the optimal (log-rank test) split. Overall survival and TTR were evaluated using univariate and multivariable analyses. RESULTS: In the MGH cohort, 233 node-negative patients following NAT were included. A LNY ≥ 22 was associated with prolonged median OS (59 months vs. 25 months, P<0.001) and prolonged TTR (32 months vs. 14 months, P=0.019). On multivariable analysis, LNY was an independent predictor of survival (HR 0.97, 95% CI 0.95-0.99, P=0.034) per sampled node. In the NCDB, 2,029 node-negative patients following NAT were included. A LNY ≥ 22 was associated with prolonged median OS (49 months vs. 33 months, P<0.001). On multivariable analysis, LNY was an independent predictor of survival (HR 0.99, 95% CI 0.98-0.99, P<0.001) per sampled node. CONCLUSION: Lymph node yield was associated with improved oncologic outcomes in patients treated with NAT followed by pancreatoduodenectomy in two independent datasets. Responsible mechanisms by which LNY impacts the outcomes of node-negative patients following NAT warrant further exploration.

Do Complications After Pancreatoduodenectomy Have an Impact on Long-Term Quality of Life and Functional Outcomes?

Objective: Our aim was to assess whether complications after pancreatoduodenectomy (PD) impact long-term quality of life (QoL) and functional outcomes. Background: There is an increasing number of long-term post-PD survivors, but few studies have evaluated long-term QoL outcomes. Methods: The EORTC QLQ-C30 and QLQ-PAN26 questionnaires were administered to patients who survived >5 years post-PD. Clinical relevance (CR) was scored as small (5-10), moderate (10-20), or large (>20). Patients were stratified based on whether they experienced a complication during the index hospitalization. Results: Of 305 patients >5 years post-PD survivors, with valid contact information, 248 completed the questionnaires, and 231 had complication data available. Twenty-nine percent of patients experienced a complication, of which 17 (7.4%) were grade 1, 27 (11.7%) were grade 2, and 25 (10.8%) were grade 3. Global health status and functional domain scores were similar between both groups. Patients experiencing complications reported lower fatigue (21.4 vs 28.1, P < 0.05, CR small) and diarrhea (15.9 vs 23.1, P < 0.05, CR small) symptom scores when compared to patients without complications. Patients experiencing complications also reported lower pancreatic pain (38.2 vs 43.4, P < 0.05, CR small) and altered bowel habits (30.1 vs 40.7, P < 0.01, CR moderate) symptom scores. There was a lower prevalence of worrying (36.2% vs 60.5%, P < 0.05) and bloating (42.0% vs 56.2%, P < 0.05) among PD survivors with complications. Conclusions: Post-PD complication rates were not associated with long-term global QoL or functionality, and may be associated with less severe pancreas-specific symptoms.

Advancements in Neuroendocrine Neoplasms: Imaging and Future Frontiers.

Neuroendocrine neoplasms (NENs) are a diverse group of tumors with varying clinical behaviors. Their incidence has risen due to increased awareness, improved diagnostics, and aging populations. The 2019 World Health Organization classification emphasizes integrating radiology and histopathology to characterize NENs and create personalized treatment plans. Imaging methods like CT, MRI, and PET/CT are crucial for detection, staging, treatment planning, and monitoring, but each of them poses different interpretative challenges and none are immune to pitfalls. Treatment options include surgery, targeted therapies, and chemotherapy, based on the tumor type, stage, and patient-specific factors. This review aims to provide insights into the latest developments and challenges in NEN imaging, diagnosis, and management.

ß2-microglobulin expression is associated with aggressive histology, activated tumor immune milieu, and outcome in colon carcinoma.

OBJECTIVES: We sought to assess the expression of human leukocyte antigen (HLA) proteins and ß2-microglobulin (B2M) in tumor cells and the relationship with immune microenvironment and outcome in colorectal cancer (CRC). METHODS: A total of 953 CRC cases were evaluated by immunohistochemistry for HLA class I, HLA class II, and B2M. The expression level of these biomarkers was correlated with clinicopathologic information, BRAF V600E and mismatch repair (MMR) proteins, and the quantitated expression levels of immune cells (CD8 and CD163) and immune regulatory proteins (FoxP3, programmed cell death 1 ligand 1 [PD-L1], and LAG3). RESULTS: We found that B2M-low tumors were statistically correlated with aggressive histologic features, including higher stage, higher grade, extramural venous invasion, perineural invasion, and distant metastasis. Expression of B2M was positively correlated (R2 = 0.3) and significantly associated with MMR-deficient tumors (P < .001); B2M-low tumors were also associated with an "immune cold"' microenvironment, including a reduced number of immune cells (CD8 and CD163), reduced expression of immune regulatory proteins by immune cells (PD-L1, FoxP3, and LAG3), and reduced tumor cell expression of PD-L1. These B2M-low tumors correlated with lower disease-specific survival (P = .018), a finding that maintained significance only for the proficient MMR cohort (P = .037). CONCLUSIONS: Our findings suggest that B2M expression may support predictive models for both outcome and checkpoint inhibitor therapy treatment response for colorectal adenocarcinoma.

Reappraising the Role of Intraoperative Neck Margin Revision in Post-Neoadjuvant Pancreatoduodenectomy for Pancreatic Ductal Adenocarcinoma: A Multi-Institutional Analysis.

OBJECTIVE: To investigate whether revision of pancreatic neck margin based on intraoperative frozen section analysis has oncologic value in post-neoadjuvant pancreatoduodenectomy (PD) for pancreatic ductal adenocarcinoma (PDAC). SUMMARY BACKGROUND DATA: The role of intraoperative neck margin revision has been controversial, with little information specific to post-neoadjuvant PD. METHODS: Patients who underwent post-neoadjuvant PD (2013-2019) for conventional PDAC with frozen section analysis of neck margin at three academic institutions were included. Overall survival (OS) and recurrence-free survival (RFS) were compared across three groups: complete resection achieved en-bloc (CR-EB), complete resection achieved non-en-bloc (CR-NEB), and incomplete resection (IR). RESULTS: Among the 671 patients included, 524 (78.1%) underwent CR-EB, 119 (17.7%) CR-NEB and 28 (4.2%) IR. Patients undergoing CR-NEB and IR exhibited larger tumors and lower rates of RECIST response, requiring vascular resections more often. Likewise, CR-NEB and IR were associated with a worse pathological profile than CR-EB. The incidence of postoperative complications and access to adjuvant treatment were comparable among groups. A CR-EB was associated with the longest OS duration (34.3 mo). In patients with positive neck margin, obtaining a CR-NEB via re-excision was associated with a comparable OS relative to patients with an IR (26.9 vs. 27.1 mo, P=0.901). Similar results were observed for RFS. At multivariable analysis, neck margin status was not independently associated with survival and recurrence. CONCLUSION: Conversion of an initially positive pancreatic neck margin by additional resection is not associated with oncologic benefits in post-neoadjuvant PD and cannot be routinely recommended.

Common hepatic artery lymph node metastasis in pancreatic ductal adenocarcinoma: an analysis of actual survival.

BACKGROUND: The common hepatic artery lymph node (CHALN) represents a second-echelon node for tumors in the head of the pancreas. Although early studies suggested survival was comparable between the CHALN and remote metastasis in pancreatic ductal adenocarcinoma (PDAC), whether the lymph node is associated with adverse survival remains equivocal. Here, we examined a prospective cohort of patients calculating actual survival to better understand implications of this specific lymph node metastasis. METHODS: We studied 215 patients with pancreatic head PDAC, who underwent pancreaticoduodenectomies at a single institution between 2010 and 2017, wherein the CHALNs were excised. We performed actual and actuarial overall survival and disease-free survival (DFS) analyses, with subsequent univariate and multivariate analyses in node-positive patients. RESULTS: Of this cohort, 7.3% of patients had involvement of the CHALN, and all of them had metastatic spread to first-echelon nodes. Actual median survival of patients with no lymph node involvement was 49 months. In patients with any nodal involvement, the survival was no different when comparing the lymph node positive and negative (13 and 20 months, respectively). Univariate and multivariate analyses likewise attached no significance to the lymph node metastasis, while demonstrating worse survival with positive margin status and poorly differentiated histology. Our DFS analyses yielded similar results. CONCLUSION: We found no difference in actual survival in node-positive patients regardless of the CHALN involvement and recommended against its assessment in prognosticating survival or guiding surgical treatment.

Chimeric Antigen Receptor T Cell with an Inducible Caspase-9 Suicide Gene Eradicates Uveal Melanoma Liver Metastases via B7-H3 Targeting.

PURPOSE: Uveal melanoma (UM) is the most common intraocular malignant tumor. Despite successful treatment of the primary tumor, about 50% of patients will recur with systemic diseases for which there are no effective treatment strategies. Here we investigated the preclinical efficacy of a chimeric antigen receptor (CAR) T-cell-based immunotherapy targeting B7-H3. EXPERIMENTAL DESIGN: B7-H3 expression on primary and metastatic human UM samples and cell lines was assessed by RNA sequencing, flow cytometry, and immunohistochemistry. Antitumor activity of CAR T cells targeting B7-H3 was tested in vitro with UM cell lines, patient-derived organotypic tumor spheroids from patients with metastatic UM, and in immunodeficient and humanized murine models. RESULTS: B7-H3 is expressed at high levels in >95% UM tumor cells in vitro and in vivo. We generated a B7-H3 CAR with an inducible caspase-9 (iCas9) suicide gene controlled by the chemical inducer of dimerization AP1903, which effectively kills UM cells in vitro and eradicates UM liver metastases in murine models. Delivery of iCas9.B7-H3 CAR T cells in experimental models of UM liver metastases demonstrates a durable antitumor response, even upon tumor rechallenge or in the presence of a significant metastatic disease burden. We demonstrate effective iCas9.B7-H3 CAR T-cell elimination in vitro and in vivo in response to AP1903. Our studies demonstrate more effective tumor suppression with iCas9.B7-H3 CAR T cells as compared to a B7-H3-targeted humanized monoclonal antibody. CONCLUSIONS: These studies support a phase I clinical trial with iCas9.B7-H3 CAR T cells to treat patients with metastatic UM.

Imaging of Neuroendocrine Neoplasms; Principles of Treatment Strategies. What Referring Clinicians Want to Know.

ABSTRACT: Neuroendocrine neoplasms (NENs) are a diverse group of tumors that express neuroendocrine markers and primarily affect the lungs and digestive system. The incidence of NENs has increased over time due to advancements in imaging and diagnostic techniques. Effective management of NENs requires a multidisciplinary approach, considering factors such as tumor location, grade, stage, symptoms, and imaging findings. Treatment strategies vary depending on the specific subtype of NEN. In this review, we will focus on treatment strategies and therapies including the information relevant to clinicians in order to undertake optimal management and treatment decisions, the implications of different therapies on imaging, and how to ascertain their possible complications and treatment effects.

Disrupting CD38-driven T cell dysfunction restores sensitivity to cancer immunotherapy.

A central problem in cancer immunotherapy with immune checkpoint blockade (ICB) is the development of resistance, which affects 50% of patients with metastatic melanoma1,2. T cell exhaustion, resulting from chronic antigen exposure in the tumour microenvironment, is a major driver of ICB resistance3. Here, we show that CD38, an ecto-enzyme involved in nicotinamide adenine dinucleotide (NAD+) catabolism, is highly expressed in exhausted CD8+ T cells in melanoma and is associated with ICB resistance. Tumour-derived CD38hiCD8+ T cells are dysfunctional, characterised by impaired proliferative capacity, effector function, and dysregulated mitochondrial bioenergetics. Genetic and pharmacological blockade of CD38 in murine and patient-derived organotypic tumour models (MDOTS/PDOTS) enhanced tumour immunity and overcame ICB resistance. Mechanistically, disrupting CD38 activity in T cells restored cellular NAD+ pools, improved mitochondrial function, increased proliferation, augmented effector function, and restored ICB sensitivity. Taken together, these data demonstrate a role for the CD38-NAD+ axis in promoting T cell exhaustion and ICB resistance, and establish the efficacy of CD38 directed therapeutic strategies to overcome ICB resistance using clinically relevant, patient-derived 3D tumour models.

Interplay between B7-H3 and HLA class I in the clinical course of pancreatic ductal adenocarcinoma.

Human leukocyte antigen (HLA) class I defects are associated with cancer progression. However, their prognostic significance is controversial and may be modulated by immune checkpoints. Here, we investigated whether the checkpoint B7-H3 modulates the relationship between HLA class I and pancreatic ductal adenocarcinoma (PDAC) prognosis. PDAC tumors were analyzed for the expression of B7-H3, HLA class I, HLA class II molecules, and for the presence of tumor-infiltrating immune cells. We observed defective HLA class I and HLA class II expressions in 75% and 59% of PDAC samples, respectively. HLA class I and B7-H3 expression were positively related at mRNA and protein level, potentially because of shared regulation by RELA, a sub-unit of NF-kB. High B7-H3 expression and low CD8+ T cell density were indicators of poor survival, while HLA class I was not. Defective HLA class I expression was associated with unfavorable survival only in patients with low B7-H3 expression. Favorable survival was observed only when HLA class I expression was high and B7-H3 expression low. Our results provide the rationale for targeting B7-H3 in patients with PDAC tumors displaying high HLA class I levels.