Chymotrypsin activity signals to intestinal epithelium by protease-activated receptor-dependent mechanisms.

BACKGROUND AND PURPOSE: Chymotrypsin is a pancreatic protease secreted into the lumen of the small intestine to digest food proteins. We hypothesized that chymotrypsin activity may be found close to epithelial cells and that chymotrypsin signals to them via protease-activated receptors (PARs). We deciphered molecular pharmacological mechanisms and gene expression regulation for chymotrypsin signalling in intestinal epithelial cells. EXPERIMENTAL APPROACH: The presence and activity of chymotrypsin were evaluated by Western blot and enzymatic activity tests in the luminal and mucosal compartments of murine and human gut samples. The ability of chymotrypsin to cleave the extracellular domain of PAR1 or PAR2 was assessed using cell lines expressing N-terminally tagged receptors. The cleavage site of chymotrypsin on PAR1 and PAR2 was determined by HPLC-MS analysis. The chymotrypsin signalling mechanism was investigated in CMT93 intestinal epithelial cells by calcium mobilization assays and Western blot analyses of (ERK1/2) phosphorylation. The transcriptional consequences of chymotrypsin signalling were analysed on colonic organoids. KEY RESULTS: We found that chymotrypsin was present and active in the vicinity of the colonic epithelium. Molecular pharmacological studies have shown that chymotrypsin cleaves both PAR1 and PAR2 receptors. Chymotrypsin activated calcium and ERK1/2 signalling pathways through PAR2, and this pathway promoted interleukin-10 (IL-10) up-regulation in colonic organoids. In contrast, chymotrypsin disarmed PAR1, preventing further activation by its canonical agonist, thrombin. CONCLUSION AND IMPLICATIONS: Our results highlight the ability of chymotrypsin to signal to intestinal epithelial cells via PARs, which may have important physiological consequences in gut homeostasis.

Curative surgical treatment of common bile duct stones: Retrospective cohort study.

BACKGROUND: In the event of symptomatic common bile duct (CBD) stones with dilated CBD, one possible curative treatment option is stone extraction through choledocotomy associated with cholecystectomy. Endoscopic treatment is only reserved for residual stones at 6 weeks. The aim of this study was to evaluate the results from laparoscopic curative surgical treatment of CBD stones with dilated CBD. METHODS: This is a retrospective single-centered cohort study. All consecutive patients admitted for laparoscopic cholecystectomy with evidence of CBD stones with dilated CBD from January 2010 to December 2020 at our center were included. Success was defined by CBD clearance at 6 weeks. Need for additional procedures, such as endoscopic sphincterotomy, immediate, and end-of-procedure morbi-mortality as well as factors associated with procedure failure, were also studied. RESULTS: A total of 246 patients who received curative treatment were included in the study. The success rate for the curative treatment was 93.1% (229 patients). Immediate postoperative morbidity was 24.4% with a 5.3% reintervention rate. Immediate and 6-week postoperative mortality rates were zero and 0.4%, respectively. The mean length of stay was 11.3 days. Factors associated with procedure failure appeared to be the occurrence of an early postoperative complication and the need for readmission during the period between surgery and drain removal. CONCLUSION: This study indicates that laparoscopic curative surgical treatment for symptomatic CBD stones may be performed with acceptable results without routine need for additional procedures.

Performance of a blood-based RNA signature for gemcitabine-based treatment in metastatic pancreatic adenocarcinoma.

Background: Pancreatic ductal adenocarcinoma (PDAC) is a highly lethal cancer, and chemotherapy is a key treatment for advanced PDAC. Gemcitabine chemotherapy is still an important component of treatment; however, there is no routine biomarker to predict its efficacy. Predictive tests may help clinicians to decide on the best first-line chemotherapy. Methods: This study is a confirmatory study of a blood-based RNA signature, called the GemciTest. This test measures the expression levels of nine genes using real-time polymerase chain reaction (PCR) processes. Clinical validation was carried out, through a discovery and a validation phases, on 336 patients (mean 68.7 years; range, 37-88 years) for whom blood was collected from two prospective cohorts and two tumor biobanks. These cohorts included previously untreated advanced PDAC patients who received either a gemcitabine- or fluoropyrimidine-based regimen. Results: Gemcitabine-based treated patients with a positive GemciTest (22.9%) had a significantly longer progression-free survival (PFS) {5.3 vs. 2.8 months; hazard ratio (HR) =0.53 [95% confidence interval (CI): 0.31-0.92]; P=0.023} and overall survival (OS) [10.4 vs. 4.8 months; HR =0.49 (95% CI: 0.29-0.85); P=0.0091]. On the contrary, fluoropyrimidine-based treated patients showed no significant difference in PFS and OS using this blood signature. Conclusions: The GemciTest demonstrated that a blood-based RNA signature has the potential to aid in personalized therapy for PDAC, leading to better survival rates for patients receiving a gemcitabine-based first-line treatment.

Pancreatic Cancer in Chronic Pancreatitis: Pathogenesis and Diagnostic Approach.

Chronic pancreatitis is one of the main risk factors for pancreatic cancer, but it is a rare event. Inflammation and oncogenes work hand in hand as key promoters of this disease. Tobacco is another co-factor. During alcoholic chronic pancreatitis, the cumulative risk of cancer is estimated at 4% after 15 to 20 years. This cumulative risk is higher in hereditary pancreatitis: 19 and 12% in the case of PRSS1 and SPINK1 mutations, respectively, at an age of 60 years. The diagnosis is difficult due to: (i) clinical symptoms of cancer shared with those of chronic pancreatitis; (ii) the parenchymal and ductal remodeling of chronic pancreatitis rendering imaging analysis difficult; and (iii) differential diagnoses, such as pseudo-tumorous chronic pancreatitis and paraduodenal pancreatitis. Nevertheless, the occurrence of cancer during chronic pancreatitis must be suspected in the case of back pain, weight loss, unbalanced diabetes, and jaundice, despite alcohol withdrawal. Imaging must be systematically reviewed. Endoscopic ultrasound-guided fine-needle biopsy can contribute by targeting suspicious tissue areas with the help of molecular biology (search for KRAS, TP53, CDKN2A, DPC4 mutations). Short-term follow-up of patients is necessary at the clinical and paraclinical levels to try to diagnose cancer at a surgically curable stage. Pancreatic surgery is sometimes necessary if there is any doubt.

The PRSS3P2 and TRY7 deletion copy number variant modifies risk for chronic pancreatitis.

BACKGROUND: PRSS1 and PRSS2 constitute the only functional copies of a tandemly-arranged five-trypsinogen-gene cluster (i.e., PRSS1, PRSS3P1, PRSS3P2, TRY7 and PRSS2) on chromosome 7q35. Variants in PRSS1 and PRSS2, including missense and copy number variants (CNVs), have been reported to predispose to or protect against chronic pancreatitis (CP). We wondered whether a common trypsinogen pseudogene deletion CNV (that removes two of the three trypsinogen pseudogenes, PRSS3P2 and TRY7) might be associated with CP causation/predisposition. METHODS: We analyzed the common PRSS3P2 and TRY7 deletion CNV in a total of 1536 CP patients and 3506 controls from France, Germany, India and Japan by means of quantitative fluorescent multiplex polymerase chain reaction. RESULTS: We demonstrated that the deletion CNV variant was associated with a protective effect against CP in the French, German and Japanese cohorts whilst a trend toward the same association was noted in the Indian cohort. Meta-analysis under a dominant model yielded a pooled odds ratio (OR) of 0.68 (95% confidence interval (CI) 0.52-0.89; p = 0.005) whereas an allele-based meta-analysis yielded a pooled OR of 0.84 (95% CI 0.77-0.92; p = 0.0001). This protective effect is explicable by reference to the recent finding that the still functional PRSS3P2/TRY7 pseudogene enhancers upregulate pancreatic PRSS2 expression. CONCLUSIONS: The common PRSS3P2 and TRY7 deletion CNV was associated with a reduced risk for CP. This finding provides additional support for the emerging view that dysregulated PRSS2 expression represents a discrete mechanism underlying CP predisposition or protection.

Study of postoperative complications after the implementation of a multidisciplinary care pathway for patients with digestive endometriosis.

PURPOSE: To assess the quality of care following the establishment of a multidisciplinary care pathway for patient operated on for deep pelvic endometriosis with digestive impairment. METHODS: We conducted a retrospective monocentric study of patients suffering from deep infiltrating endometriosis, treated in Gynaecological Department at Toulouse University Hospital from January 2018 to December 2020. We compared our results to those of our previous study, Gornes et al. which showed a postoperative complication occurred in 37.8% of the cases and a postoperative severe complication according to the Clavien-Dindo classification (grades 3b) rate of 18.3%. RESULTS: 98 patients were included. Our study shows a clear decrease in postoperative complications with an overall complication rate of 19.4% and severe complications (grades 3b) of 4.1%. The rate of complication appeared to be significantly less frequent in the case of shaving in relation to other digestive procedures (p = 0.008) and in the case of a lesion of < 20 mm by MRI (p = 0.01). The use of multidisciplinary surgical care was more frequent in the case of multiple locations (66.7% vs. 41.8%, p = 0.07) and was more frequent in the case of transmural damage with echo endoscopy (and to a lesser degree in the case of damage of the muscularis or mucous membrane) (p = 0.05). CONCLUSIONS: Multidisciplinary care of endometriosis with digestive damage appears to be indispensable. The intraoperative intervention of a skilled digestive surgeon of bowel endometriosis helps create the best balance between effectiveness-complications-functional prognosis, with a reduction of severe postoperative complications.

Prevention of post-operative recurrence of Crohn's disease among patients with prior anti-TNFα failure: A retrospective multicenter study.

BACKGROUND: Anti-TNFα are recommended for preventing Crohn's disease (CD) postoperative recurrence (POR) in patients with risk factors. However, few data exploring anti-TNFα efficacy in patients with preoperative anti-TNFα failure are available so far. AIMS: The aim of the present study was to compare the efficacy of anti-TNFα with other biologics and immunosuppressants to prevent POR in this setting. METHODS: Consecutive CD patients who underwent bowel resection between January 2010 and December 2019 after failure of at least one anti-TNFα were retrospectively included among three tertiary centers if they started a postoperative medical prophylaxis within the three months after index surgery. The main outcome was to compare rates of objective recurrence (endoscopic or radiological recurrence in absence of colonoscopy) between patients treated with an anti-TNFα agent or another treatment as prevention of POR. RESULTS: Among the 119 patients included, 71 patients received an anti-TNFα (26 infliximab, 45 adalimumab) and 48 another treatment (18 ustekinumab, 7 vedolizumab, 20 azathioprine and 3 methotrexate) to prevent POR. Rates of objective recurrence at two years were 23.9% in patients treated with anti-TNFα and 44.9% in the others (p = 0.011). CONCLUSION: Anti-TNFα remained an effective option to prevent POR for patients operated upon with previous anti-TNFα failure.

Long-Term Follow-Up and Immunomonitoring of Relapsing Type 1 Autoimmune Pancreatitis Treated With Rituximab.

OBJECTIVES: To evaluate the efficacy and safety of rituximab in relapsing type 1 autoimmune pancreatitis especially the long-term clinical and immunologic impacts. METHODS: All consecutive patients with type 1 autoimmune pancreatitis were retrospectively included. The rituximab protocol was induction therapy of 375 mg·m -2 intravenous weekly for 4 weeks, followed by 500 mg intravenous every 6 months for 2 years. The follow-up included clinical examinations, biological tests, positron emission tomography scan, and immunomonitoring of lymphocyte CD 19+. RESULTS: Among the 43 patients included, 15 received rituximab induction therapy, followed by maintenance in 10 cases because of 1 or more relapses after steroids (whether or not followed by immunosuppressants) and multiple organ involvement. All patients had a clinical, biological and morphological response, a deep and persistent drop in serum immunoglobulin G4 levels, an extinction of both pancreatic and extra pancreatic hypermetabolic positron emission tomography scan signals, and a depletion of B lymphocyte CD19+. No relapse occurred during the follow-up (62.8 ± standard error of the mean of 11.1 months). CONCLUSIONS: Rituximab is an effective treatment for type 1 autoimmune pancreatitis that provides a rapid strong clinical, biological, and morphological response, which persists after discontinuation without any safety issues.

Endoscopic ultrasound as a reliable tool for assessment of pancreatic adenocarcinoma treatment: Example of in situ gene therapy.

Background and study aims In pancreatic cancer, the antitumor effect can only be assessed by means of a computed tomography (CT) scan using RECIST (Response Evaluation Criteria in Solid Tumours) criteria. The aim of this study was to assess the intra-observer and interobserver agreement of endoscopic ultrasound (EUS) imaging in assessing tumor volume in primary pancreatic cancer. Patients and methods During a Phase 1 gene therapy trial, 21 patients had EUS before the first and second EUS-guided in situ gene therapy injections. All anonymized EUS files were then randomly distributed to three gastroenterologists/endosonographers and three radiologists (blind status). The largest tumor diameter was measured and the intraclass correlation coefficient (ICC) was determined. Results Intra-observer and interobserver agreements were good to excellent, regardless of operator experience (junior versus senior member of staff) (ICC: 0.65 to 0.84). A comparison of pretreatment and post-treatment measurements by the investigators highlighted a significant antitumor effect (-11 %; P  = 0.0098), similar to that obtained during the generic protocol (-10 %; P  = 0.0045). Conclusions Interobserver agreement regarding primary pancreatic adenocarcinoma measurements appears good to excellent, thus paving the way for the future inclusion of EUS assessments, particularly in trials assessing local therapies for pancreatic tumors.

Incidence and Risk Factors of Cancer in the Anal Transitional Zone and Ileal Pouch following Surgery for Ulcerative Colitis and Familial Adenomatous Polyposis.

Proctocolectomy with ileal pouch-anal anastomosis is the intervention of choice for ulcerative colitis and familial adenomatous polyposis requiring surgery. One of the long-term complications is pouch cancer, having a poor prognosis. The risk of high-grade dysplasia and cancer in the anal transitional zone and ileal pouch after 20 years is estimated to be 2 to 4.5% and 3 to 10% in ulcerative colitis and familial polyposis, respectively. The risk factors for ulcerative colitis are the presence of pre-operative dysplasia or cancer, disease duration > 10 years and severe villous atrophy. For familial polyposis, the risk factors are the number of pre-operative polyps > 1000, surgery with stapled anastomosis and the duration of follow-up. In the case of ulcerative colitis, a pouchoscopy should be performed annually if one of the following is present: dysplasia and cancer at surgery, primary sclerosing cholangitis, villous atrophy and active pouchitis (every 5 years without any of these factors). In the case of familial polyposis, endoscopy is recommended every year including chromoendoscopy. Even if anal transitional zone and ileal pouch cancers seldom occur following proctectomy for ulcerative colitis and familial adenomatous polyposis, the high mortality rate associated with this complication warrants endoscopic monitoring.

Adipose-Derived Stem Cells in the Treatment of Perianal Fistulas in Crohn's Disease: Rationale, Clinical Results and Perspectives.

Between 20 to 25% of Crohn's disease (CD) patients suffer from perianal fistulas, a marker of disease severity. Seton drainage combined with anti-TNFα can result in closure of the fistula in 70 to 75% of patients. For the remaining 25% of patients there is room for in situ injection of autologous or allogenic mesenchymal stem cells such as adipose-derived stem/stromal cells (ADSCs). ADSCs exert their effects on tissues and effector cells through paracrine phenomena, including the secretome and extracellular vesicles. They display anti-inflammatory, anti-apoptotic, pro-angiogenic, proliferative, and immunomodulatory properties, and a homing within the damaged tissue. They also have immuno-evasive properties allowing a clinical allogeneic approach. Numerous clinical trials have been conducted that demonstrate a complete cure rate of anoperineal fistulas in CD ranging from 46 to 90% of cases after in situ injection of autologous or allogenic ADSCs. A pivotal phase III-controlled trial using allogenic ADSCs (Alofisel®) demonstrated that prolonged clinical and radiological remission can be obtained in nearly 60% of cases with a good safety profile. Future studies should be conducted for a better knowledge of the local effect of ADSCs as well as for a standardization in terms of the number of injections and associated procedures.

Pancreatic cancer intrinsic PI3Kα activity accelerates metastasis and rewires macrophage component.

Pancreatic ductal adenocarcinoma (PDAC) patients frequently suffer from undetected micro-metastatic disease. This clinical situation would greatly benefit from additional investigation. Therefore, we set out to identify key signalling events that drive metastatic evolution from the pancreas. We searched for a gene signature that discriminate localised PDAC from confirmed metastatic PDAC and devised a preclinical protocol using circulating cell-free DNA (cfDNA) as an early biomarker of micro-metastatic disease to validate the identification of key signalling events. An unbiased approach identified, amongst actionable markers of disease progression, the PI3K pathway and a distinctive PI3Kα activation signature as predictive of PDAC aggressiveness and prognosis. Pharmacological or tumour-restricted genetic PI3Kα-selective inhibition prevented macro-metastatic evolution by hindering tumoural cell migratory behaviour independently of genetic alterations. We found that PI3Kα inhibition altered the quantity and the species composition of the produced lipid second messenger PIP3 , with a selective decrease of C36:2 PI-3,4,5-P3 . Tumoural PI3Kα inactivation prevented the accumulation of pro-tumoural CD206-positive macrophages in the tumour-adjacent tissue. Tumour cell-intrinsic PI3Kα promotes pro-metastatic features that could be pharmacologically targeted to delay macro-metastatic evolution.

Primary Intestinal Lymphangiectasia: Diagnostic Accuracy of 99mTc-Labeled Human Serum Albumin Nanocolloid SPECT/CT Before Biopsy.

Primary intestinal lymphangiectasia is an unusual cause of protein losing enteropathy due to either congenital malformation or obstruction of lymphatics of intestine. The disease can affect all or only a small part of the small intestine. Peripheral lymphedema may be associated. The diagnosis is based on endoscopic and histopathological findings. A 30-year-old woman presents lower extremity edema with hypoproteinemia, hypoalbuminemia, and hypogammaglobulinemia. Tc-labeled human serum albumin nanocolloid lymphoscintigraphy of the lower extremity demonstrated a dermal backflow in the right extremity consistent with lymphedema and an unusual ileal uptake on SPECT/CT. Diagnosis is confirmed on histopathological evaluation of biopsy of ileum.

Increased Mucosal Thrombin is Associated with Crohn's Disease and Causes Inflammatory Damage through Protease-activated Receptors Activation.

BACKGROUND AND AIMS: Thrombin levels in the colon of Crohn's disease patients have recently been found to be elevated 100-fold compared with healthy controls. Our aim was to determine whether and how dysregulated thrombin activity could contribute to local tissue malfunctions associated with Crohn's disease. METHODS: Thrombin activity was studied in tissues from Crohn's disease patients and healthy controls. Intracolonic administration of thrombin to wild-type or protease-activated receptor-deficient mice was used to assess the effects and mechanisms of local thrombin upregulation. Colitis was induced in rats and mice by the intracolonic administration of trinitrobenzene sulphonic acid. RESULTS: Active forms of thrombin were increased in Crohn's disease patient tissues. Elevated thrombin expression and activity were associated with intestinal epithelial cells. Increased thrombin activity and expression were also a feature of experimental colitis in rats. Colonic exposure to doses of active thrombin comparable to what is found in inflammatory bowel disease tissues caused mucosal damage and tissue dysfunctions in mice, through a mechanism involving both protease-activated receptors -1 and -4. Intracolonic administration of the thrombin inhibitor dabigatran, as well as inhibition of protease-activated receptor-1, prevented trinitrobenzene sulphonic acid-induced colitis in rodent models. CONCLUSIONS: Our data demonstrated that increased local thrombin activity, as it occurs in the colon of patients with inflammatory bowel disease, causes mucosal damage and inflammation. Colonic thrombin and protease-activated receptor-1 appear as possible mechanisms involved in mucosal damage and loss of function and therefore represent potential therapeutic targets for treating inflammatory bowel disease.

Primary Thromboprophylaxis in Ambulatory Pancreatic Cancer Patients Receiving Chemotherapy: A Systematic Review and Meta-Analysis of Randomized Controlled Trials.

Patients with pancreatic cancer (PC) carry the highest risk of venous thromboembolism (VTE) amongst all cancer patients. Appropriate use of primary thromboprophylaxis might significantly and safely reduce its burden. We performed a systematic review of published studies and meeting abstracts using MEDLINE and EMBASE through July 2020 to evaluate the efficacy and safety of primary thromboprophylaxis in ambulatory PC patients receiving chemotherapy. The Mantel-Haenszel random effect model was used to estimate the pooled event-based risk ratio (RR) and the pooled absolute risk difference (RD) with a 95% confidence interval (CI). Five randomized controlled studies with 1003 PC patients were included in this meta-analysis. Compared to placebo, thromboprophylaxis significantly decreased the risk of VTE (pooled RR 0.31, 95% CI 0.19-0.51, p < 0.00001, I2 = 8%; absolute RD -0.08, 95% CI -0.12--0.05, p < 0.00001, I2 = 0%), with an estimated number needed to treat of 11.9 patients to prevent one VTE event. Similar reductions of VTE were observed in studies with parenteral (RR 0.30, 95% CI 0.17-0.53) versus oral anticoagulants (RR 0.37, 95% CI 0.14-0.99) and in studies using prophylactic doses of anticoagulants (RR 0.34, 95% CI 0.17-0.70) versus supra-prophylactic doses of anticoagulants (RR 0.27, 95% CI 0.08-0.90). The pooled RR for major bleeding was 1.08 (95% CI 0.47-2.52, p = 0.85, I2 = 0%) and the absolute RD was 0.00 (95% CI -0.02-0.03, p = 0.85, I2 = 0%). Evidence supports a net clinical benefit of thromboprophylaxis in ambulatory PC patients receiving chemotherapy. Adequately powered randomized phase III studies assessing the most effective anticoagulant and the optimal dose, schedule and duration of thromboprophylaxis to be used are warranted.

Establishment of a pancreatic adenocarcinoma molecular gradient (PAMG) that predicts the clinical outcome of pancreatic cancer.

BACKGROUND: A significant gap in pancreatic ductal adenocarcinoma (PDAC) patient's care is the lack of molecular parameters characterizing tumours and allowing a personalized treatment. METHODS: Patient-derived xenografts (PDX) were obtained from 76 consecutive PDAC and classified according to their histology into five groups. A PDAC molecular gradient (PAMG) was constructed from PDX transcriptomes recapitulating the five histological groups along a continuous gradient. The prognostic and predictive value for PMAG was evaluated in: i/ two independent series (n = 598) of resected tumours; ii/ 60 advanced tumours obtained by diagnostic EUS-guided biopsy needle flushing and iii/ on 28 biopsies from mFOLFIRINOX treated metastatic tumours. FINDINGS: A unique transcriptomic signature (PAGM) was generated with significant and independent prognostic value. PAMG significantly improves the characterization of PDAC heterogeneity compared to non-overlapping classifications as validated in 4 independent series of tumours (e.g. 308 consecutive resected PDAC, uHR=0.321 95% CI [0.207-0.5] and 60 locally-advanced or metastatic PDAC, uHR=0.308 95% CI [0.113-0.836]). The PAMG signature is also associated with progression under mFOLFIRINOX treatment (Pearson correlation to tumour response: -0.67, p-value < 0.001). INTERPRETATION: PAMG unify all PDAC pre-existing classifications inducing a shift in the actual paradigm of binary classifications towards a better characterization in a gradient. FUNDING: Project funding was provided by INCa (Grants number 2018-078 and 2018-079, BACAP BCB INCa_6294), Canceropole PACA, DGOS (labellisation SIRIC), Amidex Foundation, Fondation de France, INSERM and Ligue Contre le Cancer.

Primary Thromboprophylaxis in Pancreatic Cancer Patients: Why Clinical Practice Guidelines Should Be Implemented.

Exocrine pancreatic ductal adenocarcinoma, simply referred to as pancreatic cancer (PC) has the worst prognosis of any malignancy. Despite recent advances in the use of adjuvant chemotherapy in PC, the prognosis remains poor, with fewer than 8% of patients being alive at 5 years after diagnosis. The prevalence of PC has steadily increased over the past decades, and it is projected to become the second-leading cause of cancer-related death by 2030. In this context, optimizing and integrating supportive care is important to improve quality of life and survival. Venous thromboembolism (VTE) is a common but preventable complication in PC patients. VTE occurs in one out of five PC patients and is associated with significantly reduced progression-free survival and overall survival. The appropriate use of primary thromboprophylaxis can drastically and safely reduce the rates of VTE in PC patients as shown from subgroup analysis of non-PC targeted placebo-controlled randomized trials of cancer patients and from two dedicated controlled randomized trials in locally advanced PC patients receiving chemotherapy. Therefore, primary thromboprophylaxis with a Grade 1B evidence level is recommended in locally advanced PC patients receiving chemotherapy by the International Initiative on Cancer and Thrombosis clinical practice guidelines since 2013. However, its use and potential significant clinical benefit continues to be underrecognized worldwide. This narrative review aims to summarize the main recent advances in the field including on the use of individualized risk assessment models to stratify the risk of VTE in each patient with individual available treatment options.

A New Score to Predict the Resectability of Pancreatic Adenocarcinoma: The BACAP Score.

Surgery remains the only curative treatment for pancreatic ductal adenocarcinoma (PDAC). Therefore, a predictive score for resectability on diagnosis is needed. A total of 814 patients were included between 2014 and 2017 from 15 centers included in the BACAP (the national Anatomo-Clinical Database on Pancreatic Adenocarcinoma) prospective cohort. Three groups were defined: resectable (Res), locally advanced (LA), and metastatic (Met). Variables were analyzed and a predictive score was devised. Of the 814 patients included, 703 could be evaluated: 164 Res, 266 LA, and 273 Met. The median ages of the patients were 69, 71, and 69, respectively. The median survival times were 21, 15, and nine months, respectively. Six criteria were significantly associated with a lower probability of resectability in multivariate analysis: venous/arterial thrombosis (p = 0.017), performance status 1 (p = 0.032) or ≥ 2 (p = 0.010), pain (p = 0.003), weight loss ≥ 8% (p = 0.019), topography of the tumor (body/tail) (p = 0.005), and maximal tumor size 20-33 mm (p < 0.013) or >33 mm (p < 0.001). The BACAP score was devised using these criteria (http://jdlp.fr/resectability/) with an accuracy of 81.17% and an area under the receive operating characteristic (ROC) curve of 0.82 (95% confidence interval (CI): 0.78; 0.86). The presence of pejorative criteria or a BACAP score < 50% indicates that further investigations and even neoadjuvant treatment might be warranted. Trial registration: NCT02818829.

Role of oncogenic KRAS in the diagnosis, prognosis and treatment of pancreatic cancer.

Pancreatic ductal adenocarcinoma (PDAC) is predicted to be the second most common cause of death within the next 10 years. The prognosis for this disease is poor despite diagnostic progress and new chemotherapeutic regimens. The oncogenic KRAS mutation is the major event in pancreatic cancer; it confers permanent activation of the KRAS protein, which acts as a molecular switch to activate various intracellular signalling pathways and transcription factors inducing cell proliferation, migration, transformation and survival. Several laboratory methods have been developed to detect KRAS mutations in biological samples, including digital droplet PCR (which displays high sensitivity). Clinical studies have revealed that a KRAS mutation assay in fine-needle aspiration material combined with cytopathology increases the sensitivity, accuracy and negative predictive value of cytopathology for a positive diagnosis of pancreatic cancer. In addition, the presence of KRAS mutations in serum and plasma (liquid biopsies) correlates with a worse prognosis. The presence of mutated KRAS can also have therapeutic implications, whether at the gene level per se, during its post-translational maturation, interaction with nucleotides and after activation of the various oncogenic signals. Further pharmacokinetic and toxicological studies on new molecules are required, especially small synthetic molecules, before they can be used in the therapeutic arsenal for pancreatic ductal adenocarcinoma.