Better preoperative characterization of patients with pancreatic ductal adenocarcinoma (PDAC) would aid in treatment optimization. Extracellular vesicles (EV) are promising, largely unexplored biomarkers in PDAC. This study aimed to evaluate if plasma EV characteristics are associated with PDAC clinical characteristics and overall survival (OS). The prospective cohort included 34 PDAC patients undergoing surgery with curative intent. Patient data and plasma samples were collected preoperatively, intraoperatively and one month postoperatively. Small plasma EV (sEV) concentration and size were determined by nanoparticle-tracking analysis. A Mann–Whitney test, Spearman’s rho and Cox regression were used in statistical analysis. Preoperatively, patients with poorly differentiated tumors had significantly larger plasma sEVs when compared to patients with well/moderately differentiated tumors (mean diameter 176.9 vs. 149.2 nm, p = 0.021), the sEV size even enabling discrimination of the two groups (AUC = 0.742, 95% CI = 0.560–0.923). Plasma sEV characteristics were also a predictor of OS in multivariable analysis. Patients with a more than 33.8% increase in sEV concentration after one month had 7.2 months shorter median OS (p = 0.002), while patients with a more than 28.0% decrease in sEV size had 9.2 months shorter median OS (p = 0.045). Plasma sEV concentration and size correlate with tumor differentiation and may predict OS in PDAC patients. In the future, plasma sEV characteristics could contribute to improved patient stratification for optimized treatment.
Due to possible diagnostic misjudgment of tumor resectability, patients with pancreatic ductal adenocarcinoma (PDAC) might be exposed to non-radical resection or unnecessary laparotomy. With small extracellular vesicles (sEV) obtained by liquid biopsy, we aimed to evaluate their potential as biomarkers of tumor resectability, radicality of resection and overall survival (OS). Our prospective study included 83 PDAC patients undergoing surgery with curative intent followed-up longitudinally. sEV were isolated from plasma, and their concentration and size were determined. Fifty patients underwent PDAC resection, and thirty-three had no resection. Preoperatively, patients undergoing resection had higher sEV concentrations than those without resection (p = 0.023). Resection was predicted at the cutoff value of 1.88 × 109/mL for preoperative sEV concentration (p = 0.023) and the cutoff value of 194.8 nm for preoperative mean diameter (p = 0.057). Furthermore, patients with R0 resection demonstrated higher preoperative plasma sEV concentrations than patients with R1/R2 resection (p = 0.014). If sEV concentration was above 1.88 × 109/mL or if the mean diameter was below 194.8 nm, patients had significantly longer OS (p = 0.018 and p = 0.030, respectively). Our proof-of-principle study identified preoperative sEV characteristics as putative biomarkers of feasibility and radicality of PDAC resection that also enable discrimination of patients with worse OS. Liquid biopsy with sEV could aid in PDAC patient stratification and treatment optimization in the future.
Autoimmune pancreatitis is a rare form of chronic pancreatitis of presumed autoimmune etiology. Due to significant overlap in clinical and imaging characteristics, misdiagnosis as a pancreatic malignancy is common. As a result, a significant number of patients undergo a major pancreatic resection, associated with considerable morbidity, for a disease process that generally responds well to corticosteroid therapy. In the past ten years, important advances have been made in understanding the disease. Several diagnostic criteria have been developed to aid in diagnosis. Despite this, pancreatic resection may still be required in a subset of patients to reliably exclude pancreatic malignancy and establish a definite diagnosis of autoimmune pancreatitis. This article aimed to define the role of surgery in autoimmune pancreatitis, if any. For this purpose, published case series of patients with a diagnosis of autoimmune pancreatitis, based on the histopathological examination of surgical specimens, were reviewed and patients’ clinical, radiological and serological details were assessed. At the end, histopathologic examinations of patients who underwent pancreatic resection at our department in the last 10 years were retrospectively reviewed in order to identify patients with autoimmune pancreatitis and assess their clinical characteristics.
Somatic mutations in KRAS and TP53 are among the most common genetic alterations in pancreatic ductal adenocarcinoma (PDAC). Advances in PCR-based technologies now enable the detection of these mutations in tumor tissue and cell-free DNA (cfDNA), providing a minimally invasive approach to assess tumor burden. However, in resectable PDAC, circulating tumor DNA (ctDNA) may represent less than 0.1% of total cfDNA, requiring highly sensitive detection methods. The aim of our study was to assess two PCR-based assays—competitive allele-specific PCR (castPCR) and digital PCR (dPCR)—for detecting selected somatic mutations in tumor tissue, cfDNA, and extracellular vesicle-associated DNA (EV-DNA) from plasma. Matched primary tumor and preoperative plasma samples were collected from 50 patients undergoing upfront resection for PDAC. CastPCR was used for detecting selected KRAS, TP53, SMAD4, and CDKN2A mutations in tumor DNA. Additionally, dPCR was used to analyze KRAS and TP53 mutations in tumor DNA as well as cfDNA and EV-DNA. The concordance between both platforms was 71.4% for KRAS p.G12D and 58.3% for the analysis of TP53 p.R273H mutations in tumor tissue. However, dPCR detected these mutations in an additional 28.6% and 39.6% of samples, respectively. In cfDNA, dPCR identified KRAS p.G12D in 10.2% and TP53 p.R273H in 2.0% of samples. Mutation detection in EV-DNA was limited by low DNA yield. Both platforms proved effective for tumor DNA analysis, with dPCR offering greater sensitivity. Somatic mutation detection from liquid biopsy using dPCR further supports its potential utility in the preoperative setting.
Acquired haemophilia is a rare coagulation disorder characterized by autoantibodies against coagulation factor VIII leading to severe and potentially life-threatening haemorrhages. The underlying disorder causing the development of an autoimmune phenomenon is not always known, but 10%-15% could be linked to malignancies. Patients with cancer who require surgical resection represent a treatment challenge not solely due to increased risk of bleeding but also due to adverse events of immunosuppressive therapy. We present the case of a 67-year-old man with non-metastatic adenocarcinoma of the distal bile duct who developed concomitant acquired haemophilia a month after having been diagnosed with malignant disease. Haemostasis was established with recombinant activated factor VII, and immunosuppressive therapy was started immediately. An extensive surgical procedure was performed in order to remove the cancer and, therefore, eliminate the inhibitory autoantibodies. Due to a complicated postoperative course, relatively short period of treatment and likelihood of micrometastases, no improvement in the patient’s status was observed. Diagnosis and treatment of acquired haemophilia as well as other coagulation disorders in patients with cancer are discussed. Prompt diagnosis of acquired haemophilia is required in order to start appropriate treatment and reduce mortality. Among patients with cancer, other causes of abnormal bleeding related to malignancy should be considered.