Survival Outcomes of Cytoreductive Surgery with HIPEC in Gastric Adenocarcinoma: A National Cancer Database Study.

BACKGROUND: This study aimed to assess the impact of cytoreductive surgery (CRS) with hyperthermic intraperitoneal chemotherapy (HIPEC) on the survival outcomes for patients with gastric cancer and peritoneal carcinomatosis (PC). METHODS: A retrospective analysis of the National Cancer Database from 2004 to 2020 identified patients with topography and histology codes consistent with gastric adenocarcinoma who underwent CRS/HIPEC. The exclusion criteria ruled out known other distant metastasis and missing key data. The study compared the CRS/HIPEC group with patients who had stage IV disease (with the same exclusions for distant metastases) and received systemic chemotherapy but no surgery to the primary site. RESULTS: The study included 148 patients who underwent CRS/HIPEC. Their median age was 57 years (interquartile range [IQR], 47-66 years), with 57.4% of the patients identifying as male and 73.6% identifying as white. Most of the CRS/HIPEC patients had locally advanced disease, with 33.8% having pT4 disease and 23% patients having pN3 status. The Charlson-Deyo scores were 0 for 77% and 1 for 16.9% of the patients. The overall survival (OS) among the stage IV patients managed with CRS/HIPEC was significantly longer than for the patients receiving only systemic chemotherapy (median survival, 18.1 vs 9.3 months; p < 0.001), and the 1-year OS was 72.6% versus 38.8% (p < 0.05)). Among the stage IV patients, CRS/HIPEC showed better survival than systemic chemotherapy (hazard ratio [HR], 0.57; 95% confidence interval [CI], 0.44-0.73; p < .001) when control was used for the Charlson Deyo score, histology, age, and sex. CONCLUSIONS: These results suggest the association of CRS/HIPEC with improved survival for selected patients with gastric adenocarcinoma and peritoneal disease. Some of this difference may have been due to selection bias, but the differences in the survival curves are robust.

Dynamic Anthropometrics in Pancreatic Cancer: Associations Between Body Composition Changes During Neoadjuvant Therapy and Survival Outcomes After Resection.

BACKGROUND: Assessment of individual tumor biology and response to systemic therapy in pancreatic ductal adenocarcinoma (PDAC) remains a clinical challenge. The significance of anthropometric (body composition) changes during chemotherapy as a surrogate for tumor biology in the setting of localized PDAC is unknown. METHODS: A retrospective, single-institution analysis of patients with PDAC who received neoadjuvant therapy (NAT) and pancreatectomy from 2017 to 2021 was performed. Radiologic anthropometric analysis used artificial intelligence-driven software to segment and compute total and sub-compartment muscle area, adipose tissue area, and attenuation values at the level of the L3 vertebra. Kaplan-Meier survival estimates, log-rank tests, and multivariable Cox regression models were used in survival analyses. RESULTS: The inclusion criteria were met by 138 patients. Although decreases in muscle and adipose tissue areas during NAT were predominant, a subset of patients experienced an increase in these compartments. Increases in muscle greater than 5% (hazard ratio [HR], 0.352; 95% confidence interval [CI] 0.135-0.918; p = 0.033) and increases in adipose tissue greater than 15% (HR, 0.375; 95% CI 0.144-0.978; p = 0.045), were significantly associated with improved survival, whereas loss of visceral fat greater than 15% was detrimental (HR 1.853; CI 1.099-3.124; p = 0.021). No significant associations with single time-point anthropometrics were observed. Gains in total muscle and adipose mass were associated with improved pathologic response to systemic therapy and less advanced pathologic tumor stage. CONCLUSIONS: Dynamic anthropometric analysis during NAT for PDAC is a stronger prognostic indicator than measurements taken at a single point in time. Repeated anthropometric analysis during preoperative chemotherapy may serve as a biomarker for individual tumor biology and response to therapy.

Pathological Features Associated with Lymph Node Disease in Patients with Appendiceal Neuroendocrine Tumors.

This study aimed to evaluate the role of pathological features beyond tumor size in the risk of lymph node metastasis in appendiceal neuroendocrine tumors. Analyzing data from the national cancer database, we found that among 5353 cases, 18.8% had lymph node metastasis. Focusing on tumors smaller than 2 cm, a subject of considerable debate in treatment strategies, we identified lymphovascular invasion as one of the strongest predictors of lymph node disease. Interestingly, extension into the subserosa and beyond, a current factor in the staging system, was not a strong predictor. These findings suggest that careful interpretation of pathological features is needed when selecting therapeutic approaches using current staging systems.

Multi-omics profiling to identify early plasma biomarkers in pre-diagnostic pancreatic ductal adenocarcinoma: a nested case-control study.

Pancreatic ductal adenocarcinoma (PDAC) is an aggressive disease with poor survival. Novel biomarkers are urgently needed to improve the outcome through early detection. Here, we aimed to discover novel biomarkers for early PDAC detection using multi-omics profiling in pre-diagnostic plasma samples biobanked after routine health examinations. A nested case-control study within the Northern Sweden Health and Disease Study was designed. Pre-diagnostic plasma samples from 37 future PDAC patients collected within 2.3 years before diagnosis and 37 matched healthy controls were included. We analyzed metabolites using liquid chromatography mass spectrometry and gas chromatography mass spectrometry, microRNAs by HTG edgeseq, proteins by multiplex proximity extension assays, as well as three clinical biomarkers using milliplex technology. Supervised and unsupervised multi-omics integration were performed as well as univariate analyses for the different omics types and clinical biomarkers. Multiple hypothesis testing was corrected using Benjamini-Hochberg's method and a false discovery rate (FDR) below 0.1 was considered statistically significant. Carbohydrate antigen (CA) 19-9 was associated with PDAC risk (OR [95 % CI] = 3.09 [1.31-7.29], FDR = 0.03) and increased closer to PDAC diagnosis. Supervised multi-omics models resulted in poor discrimination between future PDAC cases and healthy controls with obtained accuracies between 0.429-0.500. No single metabolite, microRNA, or protein was differentially altered (FDR < 0.1) between future PDAC cases and healthy controls. CA 19-9 levels increase up to two years prior to PDAC diagnosis but extensive multi-omics analysis including metabolomics, microRNAomics and proteomics in this cohort did not identify novel early biomarkers for PDAC.

Pathological Complete Response in Patients With Resected Pancreatic Adenocarcinoma After Preoperative Chemotherapy.

Importance: Preoperative chemo(radio)therapy is increasingly used in patients with localized pancreatic adenocarcinoma, leading to pathological complete response (pCR) in a small subset of patients. However, multicenter studies with in-depth data about pCR are lacking. Objective: To investigate the incidence, outcome, and risk factors of pCR after preoperative chemo(radio)therapy. Design, Setting, and Participants: This observational, international, multicenter cohort study assessed all consecutive patients with pathology-proven localized pancreatic adenocarcinoma who underwent resection after 2 or more cycles of chemotherapy (with or without radiotherapy) in 19 centers from 8 countries (January 1, 2010, to December 31, 2018). Data collection was performed from February 1, 2020, to April 30, 2022, and analyses from January 1, 2022, to December 31, 2023. Median follow-up was 19 months. Exposures: Preoperative chemotherapy (with or without radiotherapy) followed by resection. Main Outcomes and Measures: The incidence of pCR (defined as absence of vital tumor cells in the sampled pancreas specimen after resection), its association with OS from surgery, and factors associated with pCR. Factors associated with overall survival (OS) and pCR were investigated with Cox proportional hazards and logistic regression models, respectively. Results: Overall, 1758 patients (mean [SD] age, 64 [9] years; 879 [50.0%] male) were studied. The rate of pCR was 4.8% (n = 85), and pCR was associated with OS (hazard ratio, 0.46; 95% CI, 0.26-0.83). The 1-, 3-, and 5-year OS rates were 95%, 82%, and 63% in patients with pCR vs 80%, 46%, and 30% in patients without pCR, respectively (P < .001). Factors associated with pCR included preoperative multiagent chemotherapy other than (m)FOLFIRINOX ([modified] leucovorin calcium [folinic acid], fluorouracil, irinotecan hydrochloride, and oxaliplatin) (odds ratio [OR], 0.48; 95% CI, 0.26-0.87), preoperative conventional radiotherapy (OR, 2.03; 95% CI, 1.00-4.10), preoperative stereotactic body radiotherapy (OR, 8.91; 95% CI, 4.17-19.05), radiologic response (OR, 13.00; 95% CI, 7.02-24.08), and normal(ized) serum carbohydrate antigen 19-9 after preoperative therapy (OR, 3.76; 95% CI, 1.79-7.89). Conclusions and Relevance: This international, retrospective cohort study found that pCR occurred in 4.8% of patients with resected localized pancreatic adenocarcinoma after preoperative chemo(radio)therapy. Although pCR does not reflect cure, it is associated with improved OS, with a doubled 5-year OS of 63% compared with 30% in patients without pCR. Factors associated with pCR related to preoperative chemo(radio)therapy regimens and anatomical and biological disease response features may have implications for treatment strategies that require validation in prospective studies because they may not universally apply to all patients with pancreatic adenocarcinoma.

Radiologic Occult Metastases in Pancreatic Cancer: Analysis of Risk Factors and Survival Outcomes in the Age of Contemporary Neoadjuvant Multi-agent Chemotherapy.

BACKGROUND: Radiologic occult metastatic disease (ROMD) in patients with pancreatic ductal adenocarcinoma (PDAC) who undergo contemporary neoadjuvant chemotherapy (NAC) has not been well studied. This study sought to analyze the incidence, risk factors, and oncologic outcomes for patients who underwent the NAC approach for PDAC. METHODS: A retrospective review analyzed a prospectively maintained database of patients who had potentially resectable PDAC treated with NAC and were offered pancreatectomy at our institution from 2011 to 2022. Multivariable regression analysis was performed to assess risk factors associated with ROMD. Kaplan-Meier curves with log-rank analyses were generated to estimate time-to-event end points. RESULTS: The study enrolled 366 patients. Upfront and borderline resectable anatomic staging comprised 80% of the cohort, whereas 20% had locally advanced disease. The most common NAC regimen was FOLFIRINOX (n = 274, 75%). For 55 patients (15%) who harbored ROMD, the most common site was liver-only metastases (n = 33, 60%). The independent risk factors for ROMD were increasing CA19-9 levels during NAC (odds ratio [OR], 7.01; confidence interval [CI], 1.97-24.96; p = 0.008), indeterminate liver lesions (OR, 2.19; CI, 1.09-4.39; p = 0.028), and enlarged para-aortic lymph nodes (OR, 6.87; CI, 2.07-22.74; p = 0.002) on preoperative cross-sectional imaging. Receipt of palliative chemotherapy (p < 0.001) and eventual formal pancreatectomy (p = 0.04) were associated with survival benefit in the log-rank analysis. The median overall survival (OS) of the patients with ROMD was nearly 15 months from the initial diagnosis, with radiologic evidence of metastases occurring after a median of 2 months. CONCLUSIONS: Radiologic occult metastatic disease remains a clinical challenge associated with poor outcomes for patients who have PDAC treated with multi-agent NAC.

Adjuvant Chemotherapy With or Without Radiotherapy for Resected Pancreatic Cancer After Multiagent Neoadjuvant Chemotherapy.

BACKGROUND: Adjuvant therapy is associated with improved pancreatic cancer survival after neoadjuvant chemotherapy and surgery. However, whether adjuvant treatment should include radiotherapy is unclear in this setting. METHODS: This study queried the National Cancer Database for pancreatic adenocarcinoma patients who underwent curative resection after multiagent neoadjuvant chemotherapy between 2010 and 2019 and received adjuvant treatment. Adjuvant chemotherapy plus radiotherapy (external beam, 45-50.4 gray) was compared with adjuvant chemotherapy alone. Uni- and multivariable Cox regression was used to assess survival associations. Analyses were repeated in a propensity score-matched subgroup. RESULTS: Of 1983 patients who received adjuvant treatment after multiagent neoadjuvant chemotherapy and resection, 1502 (75.7%) received adjuvant chemotherapy alone and 481 (24.3%) received concomitant adjuvant radiotherapy (chemoradiotherapy). The patients treated with adjuvant chemoradiotherapy were younger, were treated at non-academic facilities more often, and had higher rates of lymph node metastasis (ypN1-2), positive resection margins (R1), and lymphovascular invasion (LVI+). The median survival was shorter for the chemoradiotherapy-treated patients according to the unadjusted analysis (26.8 vs 33.2 months; p = 0.0017). After adjustment for confounders, chemoradiotherapy was associated with better outcomes in the multivariable model (hazard ratio [HR], 0.75; 95% confidence interval [CI], 0.61-0.93; p = 0.008). The association between chemoradiotherapy and improved outcomes was stronger for the patients with grade III tumors (HR, 0.53; 95% CI, 0.37-0.74) or LVI+ tumors (HR, 0.58; 95% CI, 0.44-0.75). In a subgroup of 396 propensity-matched patients, chemoradiotherapy was associated with a survival benefit only for the patients with LVI+ or grade III tumors. CONCLUSION: After multiagent neoadjuvant chemotherapy and resection for pancreatic cancer, additional adjuvant chemoradiotherapy versus adjuvant chemotherapy alone is associated with improved survival for patients with LVI+ or grade III tumors.

Metabolomics for early pancreatic cancer detection in plasma samples from a Swedish prospective population-based biobank.

Background: Pancreatic ductal adenocarcinoma (pancreatic cancer) is often detected at late stages resulting in poor overall survival. To improve survival, more patients need to be diagnosed early when curative surgery is feasible. We aimed to identify circulating metabolites that could be used as early pancreatic cancer biomarkers. Methods: We performed metabolomics by liquid and gas chromatography-mass spectrometry in plasma samples from 82 future pancreatic cancer patients and 82 matched healthy controls within the Northern Sweden Health and Disease Study (NSHDS). Logistic regression was used to assess univariate associations between metabolites and pancreatic cancer risk. Least absolute shrinkage and selection operator (LASSO) logistic regression was used to design a metabolite-based risk score. We used receiver operating characteristic (ROC) analyses to assess the discriminative performance of the metabolite-based risk score. Results: Among twelve risk-associated metabolites with a nominal P value <0.05, we defined a risk score of three metabolites [indoleacetate, 3-hydroxydecanoate (10:0-OH), and retention index (RI): 2,745.4] using LASSO. A logistic regression model containing these three metabolites, age, sex, body mass index (BMI), smoking status, sample date, fasting status, and carbohydrate antigen 19-9 (CA 19-9) yielded an internal area under curve (AUC) of 0.784 [95% confidence interval (CI): 0.714-0.854] compared to 0.681 (95% CI: 0.597-0.764) for a model without these metabolites (P value =0.007). Seventeen metabolites were significantly associated with pancreatic cancer survival [false discovery rate (FDR) <0.1]. Conclusions: Indoleacetate, 3-hydroxydecanoate (10:0-OH), and RI: 2,745.4 were identified as the top candidate biomarkers for early detection. However, continued efforts are warranted to determine the usefulness of these metabolites as early pancreatic cancer biomarkers.

Interactions between the Exocrine and the Endocrine Pancreas.

The pancreas has two main functions: to produce and secrete digestive enzymes (exocrine function) and to produce hormones that regulate blood glucose and splanchnic secretion (endocrine function). The endocrine and exocrine portions of the pancreas are central regulators in digestion and metabolism, with continuous crosstalk between their deeply interconnected components, which plays a role in disease. Pancreatic neoplasms, inflammation, trauma, and surgery can lead to the development of type 3c diabetes when an insult simultaneously damages both acini and islets, leading to exocrine and endocrine dysfunction. In diabetes mellitus patients, pancreatic exocrine insufficiency is highly prevalent, yet little is known about the associations between diabetes mellitus and pancreatic exocrine function. This review aims to provide an overview of the physiology of the pancreas, summarize the pathophysiology and diagnostic work-up of pancreatic exocrine insufficiency, and explore the relationships between exocrine pancreatic insufficiency and diabetes mellitus.

Neoadjuvant Chemotherapy Versus Upfront Surgery for Resectable Pancreatic Adenocarcinoma: An Updated Nationwide Study.

OBJECTIVE: The objective of this study was to assess the association of survival with neoadjuvant chemotherapy (NAC) in resectable pancreatic adenocarcinoma (PDAC). BACKGROUND: The early control of potential micrometastases and patient selection using NAC has been advocated for patients with PDAC. However, the role of NAC for resectable PDAC remains unclear. METHODS: Patients with clinical T1 and T2 PDAC were identified in the National Cancer Database from 2010 to 2017. Kaplan-Meier estimates, and Cox regression models were used to compare survival. To address immortal time bias, landmark analysis was performed. Interactions between preoperative factors and NAC were investigated in subgroup analyses. A propensity score analysis was performed to compare survival between multiagent NAC and upfront surgery. RESULTS: In total, 4041 patients were treated with upfront surgery and 1,175 patients were treated with NAC (79.4% multiagent NAC, 20.6% single-agent NAC). Using a landmark time of 6 months after diagnosis, patients treated with multiagent NAC had longer median overall survival compared with upfront surgery and single-agent NAC. (35.8 vs 27.1 vs 27.4 mo). Multiagent NAC was associated with lower mortality rates compared with upfront surgery (adjusted hazard ratio, 0.77; 95% CI, 0.70-0.85), whereas single-agent NAC was not. The association of survival with multiagent NAC were consistent in analyses using the matched data sets. Interaction analysis revealed that the association between multiagent NAC and a lower mortality rate did not significantly differ across age, facility type, tumor location, CA 19-9 levels, and clinical T/N stages. CONCLUSIONS: The findings suggest that multiagent NAC followed by resection is associated with improved survival compared with upfront surgery.

Portomesenteric venous contact ≤180° and overall survival in resectable head and body pancreatic adenocarcinoma treated with upfront surgery.

INTRODUCTION: Upfront surgery is the standard of care for resectable pancreatic cancer, defined as the absence of or ≤180° tumour contact with the portal/superior mesenteric vein. We hypothesized that portomesenteric venous tumour contact is prognostically unfavourable and aimed to assess whether it is associated with poorer survival compared with no venous contact in resectable head and body pancreatic cancer. METHODS: This single-centre retrospective study included patients undergoing upfront surgery for resectable head and body pancreatic cancer in 2010-2020 at Umeå University Hospital, Sweden. No venous contact was compared with portomesenteric venous contact of ≤180° based on preoperative imaging. Overall survival on an intention-to-treat basis was compared with Kaplan-Meier curves, a log-rank test and Cox proportional hazards models. RESULTS: The final study cohort included 39 patients with portomesenteric venous tumour contact and 144 patients without venous tumour contact. Patients with venous tumour contact had a median overall survival of 15.3 months compared to 23.0 months (log rank P = 0.059). Portomesenteric venous tumour contact was an independent negative prognostic factor for survival in the multivariable Cox model (HR 1.68; 95% CI 1.11-2.55, P = 0.014) and was associated with higher rates of microscopically non-radical resections (R1) (50% vs 26.1%, P = 0.012) and pathological lymph node metastasis (76.7% vs 56.8%, P = 0.012). There was no difference in adjuvant chemotherapy receipt or postoperative complications between the groups. CONCLUSIONS: Portomesenteric venous tumour contact is associated with poorer overall survival and higher rates of R1 resections and lymph node metastasis in patients with resectable head and body pancreatic cancer treated with upfront surgery.

Optimal balancing of xylem efficiency and safety explains plant vulnerability to drought.

In vast areas of the world, forests and vegetation are water limited and plant survival depends on the ability to avoid catastrophic hydraulic failure. Therefore, it is remarkable that plants take hydraulic risks by operating at water potentials (ψ) that induce partial failure of the water conduits (xylem). Here we present an eco-evolutionary optimality principle for xylem conduit design that explains this phenomenon based on the hypothesis that conductive efficiency and safety are optimally co-adapted to the environment. The model explains the relationship between the tolerance to negative water potential (ψ50 ) and the environmentally dependent minimum ψ (ψmin ) across a large number of species, and along the xylem pathway within individuals of two species studied. The wider hydraulic safety margin in gymnosperms compared to angiosperms can be explained as an adaptation to a higher susceptibility to accumulation of embolism. The model provides a novel optimality-based perspective on the relationship between xylem safety and efficiency.

Management of Localized Small- and Large-Cell Pancreatic Neuroendocrine Carcinoma in the National Cancer Database.

BACKGROUND: The role of curative-intent resection and perioperative chemotherapy for nonmetastatic pancreatic neuroendocrine carcinoma (PanNEC) remains unclear due to their biological aggressiveness and rarity. This study aimed to evaluate the association of resection and perioperative chemotherapy with overall survival for nonmetastatic PanNEC. STUDY DESIGN: Patients with localized (cT1-3, M0), small- and large-cell PanNEC were identified in the National Cancer Database from 2004 to 2017. The changing trends in terms of the annual proportions of resection and adjuvant chemotherapy were assessed. The survival of patients who received resection and those who received adjuvant chemotherapy were investigated using Kaplan-Meier estimates and Cox regression models. RESULTS: In total, 199 patients with localized small- and large-cell PanNEC were identified; 50.3% of those were resected, and 45.0% of the resected patients received adjuvant chemotherapy. Rate of resection and adjuvant treatment has trended upward since 2011. The resected group was younger, was more often treated at academic institutions, had more distal tumors, and had a lower number of small-cell PanNEC. The median overall survival was longer in the resected group compared to the unresected group (29.4 months vs 8.6 months, p < 0.001). Resection was associated with improved survival in a multivariable Cox regression model adjusting for preoperative factors (adjusted hazard ratio 0.58, 95% CI 0.37 to 0.92), while adjuvant therapy was not. CONCLUSIONS: This nationwide retrospective study suggests that resection is associated with improved survival in patients with localized PanNEC. The role of adjuvant chemotherapy needs more investigation.

Re-examining the evidence for the mother tree hypothesis - resource sharing among trees via ectomycorrhizal networks.

Seminal scientific papers positing that mycorrhizal fungal networks can distribute carbon (C) among plants have stimulated a popular narrative that overstory trees, or 'mother trees', support the growth of seedlings in this way. This narrative has far-reaching implications for our understanding of forest ecology and has been controversial in the scientific community. We review the current understanding of ectomycorrhizal C metabolism and observations on forest regeneration that make the mother tree narrative debatable. We then re-examine data and conclusions from publications that underlie the mother tree hypothesis. Isotopic labeling methods are uniquely suited for studying element fluxes through ecosystems, but the complexity of mycorrhizal symbiosis, low detection limits, and small carbon discrimination in biological processes can cause researchers to make important inferences based on miniscule shifts in isotopic abundance, which can be misleading. We conclude that evidence of a significant net C transfer via common mycorrhizal networks that benefits the recipients is still lacking. Furthermore, a role for fungi as a C pipeline between trees is difficult to reconcile with any adaptive advantages for the fungi. Finally, the hypothesis is neither supported by boreal forest regeneration patterns nor consistent with the understanding of physiological mechanisms controlling mycorrhizal symbiosis.

Extracellular Galectin 4 Drives Immune Evasion and Promotes T-cell Apoptosis in Pancreatic Cancer.

Pancreatic ductal adenocarcinoma (PDAC) is characterized by rich deposits of extracellular matrix (ECM), affecting the pathophysiology of the disease. Here, we identified galectin 4 (gal 4) as a cancer cell-produced protein that was deposited into the ECM of PDAC tumors and detected high-circulating levels of gal 4 in patients with PDAC. In orthotopic transplantation experiments, we observed increased infiltration of T cells and prolonged survival in immunocompetent mice transplanted with cancer cells with reduced expression of gal 4. Increased survival was not observed in immunodeficient RAG1-/- mice, demonstrating that the effect was mediated by the adaptive immune system. By performing single-cell RNA-sequencing, we found that the myeloid compartment and cancer-associated fibroblast (CAF) subtypes were altered in the transplanted tumors. Reduced gal 4 expression associated with a higher proportion of myofibroblastic CAFs and reduced numbers of inflammatory CAFs. We also found higher proportions of M1 macrophages, T cells, and antigen-presenting dendritic cells in tumors with reduced gal 4 expression. Using a coculture system, we observed that extracellular gal 4 induced apoptosis in T cells by binding N-glycosylation residues on CD3ε/δ. Hence, we show that gal 4 is involved in immune evasion and identify gal 4 as a promising drug target for overcoming immunosuppression in PDAC.

A Cross-Sectional and Longitudinal Analysis of Pre-Diagnostic Blood Plasma Biomarkers for Early Detection of Pancreatic Cancer.

Pancreatic ductal adenocarcinoma (PDAC) is a major cause of cancer death that typically presents at an advanced stage. No reliable markers for early detection presently exist. The prominent tumor stroma represents a source of circulating biomarkers for use together with cancer cell-derived biomarkers for earlier PDAC diagnosis. CA19-9 and CEA (cancer cell-derived biomarkers), together with endostatin and collagen IV (stroma-derived) were examined alone, or together, by multivariable modelling, using pre-diagnostic plasma samples (n = 259 samples) from the Northern Sweden Health and Disease Study biobank. Serial samples were available for a subgroup of future patients. Marker efficacy for future PDAC case prediction (n = 154 future cases) was examined by both cross-sectional (ROC analysis) and longitudinal analyses. CA19-9 performed well at, and within, six months to diagnosis and multivariable modelling was not superior to CA19-9 alone in cross-sectional analysis. Within six months to diagnosis, CA19-9 (AUC = 0.92) outperformed the multivariable model (AUC = 0.81) at a cross-sectional level. At diagnosis, CA19-9 (AUC = 0.995) and the model (AUC = 0.977) performed similarly. Longitudinal analysis revealed increases in CA19-9 up to two years to diagnosis which indicates a window of opportunity for early detection of PDAC.

Circulating Tissue Polypeptide-Specific Antigen in Pre-Diagnostic Pancreatic Cancer Samples.

Early detection of pancreatic ductal adenocarcinoma (PDAC) is challenging, and late diagnosis partly explains the low 5-year survival. Novel and sensitive biomarkers are needed to enable early PDAC detection and improve patient outcomes. Tissue polypeptide specific antigen (TPS) has been studied as a biomarker in PDAC diagnostics, and it has previously been shown to reflect clinical status better than the 'golden standard' biomarker carbohydrate antigen 19-9 (CA 19-9) that is most widely used in the clinical setting. In this cross-sectional case-control study using pre-diagnostic plasma samples, we aim to evaluate the potential of TPS as a biomarker for early PDAC detection. Furthermore, in a subset of individuals with multiple samples available at different time points before diagnosis, a longitudinal analysis was used. We assessed plasma TPS levels using enzyme-linked immunosorbent assay (ELISA) in 267 pre-diagnostic PDAC plasma samples taken up to 18.8 years before clinical PDAC diagnosis and in 320 matched healthy controls. TPS levels were also assessed in 25 samples at PDAC diagnosis. Circulating TPS levels were low both in pre-diagnostic samples of future PDAC patients and in healthy controls, whereas TPS levels at PDAC diagnosis were significantly increased (odds ratio 1.03; 95% confidence interval: 1.01-1.05) in a logistic regression model adjusted for age. In conclusion, TPS levels increase late in PDAC progression and hold no potential as a biomarker for early detection.