Droplet digital polymerase chain reaction detection of KRAS mutations in pancreatic FNA samples: Technical and practical aspects for routine clinical implementation.

BACKGROUND: Pancreatic adenocarcinoma (PDAC) is associated with a 5-year survival rate of less than 6%, and current treatments have limited efficacy. The diagnosis of PDAC is mainly based on a cytologic analysis of endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) samples. However, the collected specimens may prove noncontributory in a significant number of cases, delaying patient management and treatment. The combination of EUS-FNA sample examination and KRAS mutation detection can improve the sensitivity for diagnosis. In this context, the material used for molecular analysis may condition performance. METHODS: The authors prospectively compared the performance of cytologic analysis combined with a KRAS droplet digital polymerase chain reaction (ddPCR) assay for PDAC diagnosis using either conventional formalin-fixed, paraffin-embedded cytologic samples or needle-rinsing fluids. RESULTS: Molecular testing of formalin-fixed, paraffin-embedded cytologic samples was easier to set up, but the authors observed that the treatment of preanalytic samples, in particular the fixation process, drastically reduced ddPCR sensitivity, increasing the risk of false-negative results. Conversely, the analysis of dedicated, fresh needle-rinsing fluid samples appeared to be ideal for ddPCR analysis; it had greater sensitivity and was easily to implement in clinical use. In particular, fluid collection by the endoscopist, transportation to the laboratory, and subsequent freezing did not affect DNA quantity or quality. Moreover, the addition of KRAS mutation detection to cytologic examination improved diagnosis performance, regardless of the source of the sample. CONCLUSIONS: Considering all of these aspects, the authors propose the use of an integrated flowchart for the KRAS molecular testing of EUS-FNA samples in clinical routine.

Factors associated with early failure of peroral endoscopic myotomy in achalasia.

BACKGROUND AND AIMS: Achalasia can be treated very effectively with peroral endoscopic myotomy (POEM), but factors associated with early failure remain to be determined, especially in European cohorts. METHODS: All consecutive adult patients who underwent a first POEM to treat primary achalasia were included in this multicenter retrospective study. Early failure was defined by an Eckardt score (ES) >3 at 3 months after POEM. When evaluating factors predictive of early failure, 2 cohorts were considered: one consisted of the total population, for whom only basic variables were collected, and the other a cohort built for a case-control study that included matched early-failure and early-success patients (ratio, 1:2). RESULTS: Among 746 patients, the early failure rate was 9.4%. Predictive factors were age ≤45 years (P = .019), achalasia types I and III (P < .001), and the development of a severe adverse event during the procedure (P = .023). In the case-control study, the only additional independent risk factor for early failure was a high pre-POEM ES (P = .001). Only the retrosternal pain subscore was significantly associated with the early failure rate. CONCLUSION: The early failure rate of POEM used to treat primary achalasia is <10%. Younger age, type I/III achalasia, and a high pre-POEM ES were significantly associated with failure.

Endoscopic Powered Resection Device for Residual Colonic Lesions: The First Multicenter, Prospective, International Clinical Study.

BACKGROUND AND AIMS: Endoscopic resection is standard treatment for adenomatous colorectal lesions. Depending on lesion morphology and resection technique, recurrence can occur. Scarred adenomas are challenging to resect and may require surgical management. This study evaluated safety and effectiveness of an endoscopic powered resection (EPR) system for scarred adenomatous colorectal lesions. METHODS: Single-arm, prospective, multicenter, study conducted from January 2018 to January 2021 at 12 sites. Patients with persistent flat or sessile colorectal lesions were enrolled. Primary endpoints were technical success (the ability of the device to resect the lesion(s) without use of other resection devices without device-related serious adverse events (SAE)) and safety (the occurrence of adverse events (AE) through 90 days). Secondary endpoints included endoscopic confirmation of resection completeness, occurrence of colon stenosis, disease persistence, and diagnostic value of resected specimens. RESULTS: Sixty-five patients were in the intent-to-treat / safety analysis population. Primary analysis was performed on 45 per-protocol (PP) patients with 48 lesions. All PP-patients were solely treated by the EndoRotor device. Technical success was achieved in 44 (98%) patients. Three (5%) SAEs occurred: 2 delayed self-limited bleeds and 1 perforation. Non-serious AEs included 4 (6%) cases of mild intraprocedural bleeding. Completeness of resection and histopathological diagnosis of tissue specimens were achieved in all patients, 21 (46.7%) patients had disease persistence after the first treatment, and there was no colon stenosis. CONCLUSIONS: EPR is a safe and effective for benign, persistent, large (>20mm) scarred, colorectal adenomas and should be considered as an alternative treatment in lieu of surgery. Persistence rate of 46.7% show that more than one treatment are necessary for effective endoscopic treatment.

Use of endoscopic submucosal dissection or full-thickness resection device to treat residual colorectal neoplasia after endoscopic resection: a multicenter historical cohort study.

INTRODUCTION : Residual colorectal neoplasia (RCN) after previous endoscopic mucosal resection is a frequent challenge. Different management techniques are feasible including endoscopic full-thickness resection using the full-thickness resection device (FTRD) system and endoscopic submucosal dissection (ESD). We aimed to compare the efficacy and safety of these two techniques for the treatment of such lesions. METHODS : All consecutive patients with RCN treated either using the FTRD or by ESD were retrospectively included in this multicenter study. The primary outcome was the R0 resection rate, defined as an en bloc resection with histologically tumor-free lateral and deep margins. RESULTS : 275 patients (median age 70 years; 160 men) who underwent 177 ESD and 98 FTRD procedures for RCN were included. R0 resection was achieved in 83.3 % and 77.6 % for ESD and FTRD, respectively (P = 0.25). Lesions treated by ESD were however larger than those treated by FTRD (P < 0.001). The R0 rates for lesions of 20-30 mm were 83.9 % and 57.1 % in the ESD and FTRD groups, respectively, and for lesions of 30-40 mm were 93.6 % and 33.3 %, respectively. On multivariable analysis, ESD procedures were associated with statistically higher en bloc and R0 resection rates after adjustment for lesion size (P = 0.02 and P < 0.001, respectively). The adverse event rate was higher in the ESD group (16.3 % vs. 5.1 %), mostly owing to intraoperative perforations. CONCLUSION: ESD is effective in achieving R0 resection for RCN whatever the size and location of the lesions. When residual lesions are smaller than 20 mm, the FTRD is an effective alternative.

Individual and population screening of varices needing treatment by a simple, safe and accurate test.

BACKGROUND: Several tests have been developed to screen varices needing treatment (VNT) in different screening settings. We aimed to develop simple estimators to quantify VNT risk and spare endoscopy while missing <5% of VNT, adapted to different screenings in the main etiologies. METHODS: 2,368 patients with chronic liver disease were included. The main VNT predictors were platelets, prothrombin index (PI) and LSM. Their interactions led to score construction, LIP: (LSM*45)/(PI*platelets), and BLIP: BMI-adjusted LIP in NAFLD. Scores were categorized either for population (VNT sensitivity ≥95%) or individual (negative predictive value ≥95%) VNT screening. RESULTS: 1) Scores diagnosing VNT. AUROCs were, PLER: 0.767 Anticipate: 0.773 (p=0.059 vs previous), LIP: 0.779 (p=0.136), PLEASE: 0.789 (p=0.196). 2) Population screening performance was in increasing order (with missed VNT rate), Baveno6 criteria: 23.9% (2.5%), Anticipate: 24.5%, p=0.367 vs previous (3.3%), PLER: 27.3%, p<0.001 (3.6%), LIP: 33.4%, p<0.001 (4.2%), PLEASE: 35.2%, p=0.006 (3.6%). In NAFLD, LIP: 38.6%, BLIP: 40.8%, p=0.038. 3) Individual screening performance was, expanded Baveno6 criteria: 42.7%, LIP: 54.1%, p<0.001. In NAFLD, performance was, NAFLD-cirrhosis criteria: 66.7%, BLIP: 74.6%, p<0.001. CONCLUSION: LIP combined simplicity, performance and safety in each etiology. In NAFLD, BMI-adjusted LIP outperformed other tests.

Efficacy of Organ Preservation Strategy by Adjuvant Chemoradiotherapy after Non-Curative Endoscopic Resection for Superficial SCC: A Multicenter Western Study.

BACKGROUND: In case of high risk of lymph node invasion after endoscopic resection (ER) of superficial esophageal squamous cell carcinoma (SCC), adjuvant chemoradiotherapy (CRT) can be an alternative to surgery. We assessed long-term clinical outcomes of adjuvant therapy by CRT after non-curative ER for superficial SCC. METHODS: We performed a retrospective multicenter study. From April 1999 to April 2018, all consecutive patients who underwent ER for SCC with tumor infiltration beyond the muscularis mucosae were included. RESULTS: A total of 137 ER were analyzed. The overall nodal or metastatic recurrence-free survival rate at 5 years was 88% and specific recurrence-free survival rates at 5 years with and without adjuvant therapy were, respectively, 97.9% and 79.1% (p = 0.011). Independent factors for nodal and/or distal metastatic recurrence were age (HR = 1.075, p = 0.031), Sm infiltration depth > 200 µm (HR = 4.129, p = 0.040), and the absence of adjuvant CRT or surgery (HR = 11.322, p = 0.029). CONCLUSION: In this study, adjuvant therapy is associated with a higher recurrence-free survival rate at 5 years after non-curative ER. This result suggests this approach may be considered as an alternative to surgery in selected patients.

Risk factors for clinical failure of peroral endoscopic myotomy in achalasia.

The recent development of per oral endoscopic myotomy (POEM) has been a game changer in the management of patients with achalasia. However, approximately 1 in 10 patients will not experience clinical success. The aim of this mini-review is to describe the current state of knowledge about the risk factors associated with POEM failure for the treatment of achalasia. Suspected risk factors are detailed into pre-, intra-, and post-procedural factors and put into perspective. Pre-procedural factors have been described, such as pre-treatment Eckardt score, previous treatments for achalasia, sigmoid type esophagus, significant esophageal dilatation, non-type II achalasia, young age and long duration of symptoms. An intra-procedural factor, mucosal injury during POEM, has also been associated with POEM failure. The occurrence of post-POEM GERD was identified as a controversial post-procedural factor associated with failure. The presumed mechanisms of POEM failure are incomplete myotomy or ineffective LES disruption, as confirmed by high-resolution manometry. However, when manometry confirms a significant decrease in LES pressure, it is likely that either impaired peristalsis or a morphologic abnormality such as extreme esophageal dilatation or severe tortuosity, which are not treated by POEM, should be suspected. Notably, a recently described adverse effect of POEM is the formation of a pseudo-diverticulum at the site of the myotomy (blown out myotomy). We finally stress the importance of performing a complete workup in case of POEM failure as different mechanisms of POEM failure should lead to different management.

A single dedicated vaccination visit improves vaccination coverage of patients with inflammatory bowel disease.

Introduction: Patients treated with biologics for inflammatory bowel disease (IBD) have an increased risk of severe infections. Real-life vaccination coverage in this population remains low despite international vaccination guidelines. The aim of this study was to evaluate the impact of a dedicated vaccination visit on vaccination coverage. Methods: A dedicated vaccination visit was offered to all patients admitted for an infusion of a biologic in a tertiary IBD center during a 4-week period. At baseline, vaccination status was collected. Patients received specific information on recommended vaccinations. Perceived utility of both vaccination and the dedicated visit were assessed by visual analogue scale (VAS). Vaccination coverage was reassessed 6 months later by phone call. Results: Among the 207 patients analyzed (1 patient declined), rates of vaccination at baseline and 6 months later against diphtheria were 52.7% and 68.6% (p < 0.001), tetanus 55.1% and 70% (p < 0.001), poliomyelitis 51.7% and 68.6% (p < 0.001), pertussis 33.3% and 51.2% (p < 0.001), hepatitis B virus (HBV) 61.4% and 66.7% (p < 0.01), pneumococcus 15.5% and 42.0% (p < 0.001), influenza 29.5% and 36.2% (p < 0.01), and meningococcus C 11.6% and 13.0% (p = 0.083), respectively. A quarter of the patients declined at least one recommended vaccination after the visit. The main reason for this refusal was distrust toward one or more vaccines. Conclusion: A single visit dedicated to vaccination significantly increases rates of vaccination in patients with IBD treated with biologics.

Comparison of screening strategies with two new tests to score and diagnose varices needing treatment.

BACKGROUND AND AIMS: We aimed to improve non-invasive screening of varices needing treatment (VNT) and compare different screening strategies. METHODS: 2,290 patients with chronic liver disease were included in a retrospective study. Etiologies were: virus: 50.0%, NAFLD: 29.5%, alcohol: 20.5%, VNT: 14.9%. Test descriptors were performance (spared endoscopy) and safety (missed VNT). VNT tests were evaluated according to their safety levels either for individual screening (95% negative predictive value (NPV)), population screening (95% sensitivity) or undifferentiated screening (100% sensitivity/NPV) without missed VNT. The tests provided three categories: missed VNT <5%, VNT 100% specificity (new category), both sparing endoscopies, and intermediate (endoscopy required). RESULTS: Independent VNT predictors (etiology, sex, age, platelets, prothrombin index, albumin, ALT, liver stiffness) were included in two tests: VNT virus alcohol NAFLD test (VANT) and varice risk score (VARS). We report results of the whole population. Considering population screening, performances were, Baveno VI criteria: 24.1%, Anticipate: 24.7%, VariScreen: 35.3%, VANT: 40.2% (p<0.001 vs other tests). VANT spared 58.0% more endoscopies in the whole population than Baveno criteria in compensated advanced chronic liver diseases. Considering individual screening, VARS performance was, in all patients: 62.0% vs 42.9% for the expanded Baveno VI criteria (p<0.001), and, in NAFLD: 72.8% vs 65.1% for the NAFLD cirrhosis criteria (p<0.001). Considering undifferentiated screening, VARS performance was 12%. The VARS score estimated VNT probability from 0 to 100% (AUROC: 0.826). CONCLUSION: VANT and VARS spared from 12% (undifferentiated screening) to 40% (population screening) or 62% (individual screening) of endoscopies in main-etiology patients without ascites.

Efficacy and safety of endoscopic papillectomy: a multicenter, retrospective, cohort study on 227 patients.

Background: Endoscopic papillectomy is a minimally invasive treatment for benign tumors of the ampulla of Vater or early ampullary carcinoma. However, reported recurrence rates are significant and risk factors for recurrence are unclear. Objective: The aims of this study were to evaluate the efficacy and safety of endoscopic papillectomy and to identify risk factors for recurrence and adverse events. Methods: All patients who underwent endoscopic papillectomy at five tertiary referral centers between January 2008 and December 2018 were included. Recurrence was defined as the detection of residue on one of the follow-up endoscopies. Treatment success was defined as the absence of tumor residue on the last follow-up endoscopy. Results: A total of 227 patients were included. The resections were en bloc in 64.8% of cases. The mean lesion size was 20 mm (range: 3-80) with lateral extension in 23.3% of cases. R0 resection was achieved in 45.3% of cases. The recurrence rate was 30.6%, and 60.7% of recurrences were successfully treated with additional endoscopic treatment. Finally, treatment success was achieved in 82.8% of patients with a median follow-up time of 22.3 months. R1 resection, intraductal invasion, and tumor size > 2 cm were associated with local recurrence. Adverse events occurred in 36.6% of patients and included pancreatitis (17.6%), post-procedural hemorrhage (11.0%), perforation (5.2%), and biliary stenosis (2.6%). The mortality rate was 0.9%. Conclusion: Endoscopic papillectomy is an effective and relatively well-tolerated treatment for localized ampullary tumors. In this series, R1 resection, intraductal invasion, and lesion size > 2 cm were associated with local recurrence.

Spin in the Scientific Literature on Bariatric Endoscopy: a Systematic Review of Randomized Controlled Trials.

Bariatric endoscopy (BE) is an emerging treatment option for people with obesity. Spin (i.e., the practice of frequent misrepresentation or overinterpretation of study findings) may lead to imbalanced and unjustified optimism in the interpretation of the results. The aim of this systematic review was to determine the frequency and type of spin in randomized controlled trials (RCTs) of endoscopic primary weight loss techniques with statistically significant and nonsignificant primary outcomes. In conclusion, spin is observed in the abstract and main text of BE reports and can lead to misinterpretation or overinterpretation of the results. Since BE challenges the available non-endoscopic treatments for obesity, further research is needed to better qualify these techniques, as being effective and safe, as well as predefined hypotheses and analyses.

Circumferential esophageal replacement by a decellularized esophageal matrix in a porcine model.

BACKGROUND: Tissue engineering is an attractive alternative to conventional esophageal replacement techniques using intra-abdominal organs which are associated with a substantial morbidity. The objective was to evaluate the feasibility of esophageal replacement by an allogenic decellularized esophagus in a porcine model. Secondary objectives were to evaluate the benefit of decellularized esophagus recellularization with autologous bone marrow mesenchymal stromal cells and omental maturation of the decellularized esophagus. METHODS: Eighteen pigs divided into 4 experimental groups according to mesenchymal stromal cells recellularization and omental maturation underwent a 5-cm long circumferential replacement of the thoracic esophagus. Turbo green florescent protein labelling was used for in vivo mesenchymal stromal cells tracking. The graft area was covered by a stent for 3 months. Clinical and histologic outcomes were analyzed over a 6-month period. RESULTS: The median follow-up was 112 days [5; 205]. Two animals died during the first postoperative month, 2 experienced an anastomotic leakage, 13 experienced a graft area stenosis following stent migration of which 3 were sacrificed as initially planned after successful endoscopic treatment. The stent could be removed in 2 animals: the graft area showed a continuous mucosa without stenosis. After 3 months, the graft area showed a tissue specific regeneration with a mature epithelium and muscular cells. Clinical and histologic results were similar across experimental groups. CONCLUSION: Circumferential esophageal replacement by a decellularized esophagus was feasible and allowed tissue remodeling toward an esophageal phenotype. We could not demonstrate any benefit provided by the omental maturation of the decellularized esophagus nor its recellularization with mesenchymal stromal cells.

Extracellular vesicles from adipose stromal cells combined with a thermoresponsive hydrogel prevent esophageal stricture after extensive endoscopic submucosal dissection in a porcine model.

In this study, we investigated the combination of extracellular (nano) vesicles (EVs) from pig adipose tissue-derived stromal cells (ADSCs) and a thermoresponsive gel, Pluronic® F-127 (PF-127), to prevent stricture formation after endoscopic resection in a porcine model. ADSC EVs were produced at a liter scale by a high-yielding turbulence approach from ADSCs 3D cultured in bioreactors and characterized in terms of size, morphology and membrane markers. The thermoresponsive property of the PF-127 gel was assessed by rheology. The pro-regenerative potency of ADSC EVs was investigated ex vivo in esophageal biopsies under starvation. In vivo tests were performed in a porcine model after extended esophageal endoscopic mucosal dissection (ESD). Pigs were randomized into 3 groups: control (n = 6), gel (n = 6) or a combination of 1.45 × 1012 EVs + gel (n = 6). Application of gel ± EVs was performed just after ESD with a follow-up finalized on day 21 post-ESD. There was a trend towards less feeding disorder in the EV + gel group in comparison with the gel and the control groups (16.67% vs. 66.7% vs. 83.33%, respectively) but without reaching a statistically significant difference. A significant decrease in the esophageal stricture rate was confirmed by endoscopic, radiological and histological examination for the EV + gel group. A decrease in the mean fibrosis area and larger regenerated muscularis mucosae were observed for the EV + gel group. In summary, the application of EVs + gel after extended esophageal endoscopic resection succeeded in preventing stricture formation with an anti-fibrotic effect. This nano-therapy may be of interest to tackle an unmet medical need considering that esophageal stricture is the most challenging delayed complication after extended superficial cancer resection by endoscopy.

A novel bowel rehabilitation programme after total mesorectal excision for rectal cancer: the BOREAL pilot study.

AIM: Low anterior resection syndrome (LARS) following sphincter-preserving surgery for rectal cancer has a high prevalence, with an impact on long-term bowel dysfunction and quality of life. We designed the bowel rehabilitation programme (BOREAL) as a proactive strategy to assess and treat patients with LARS. The BOREAL programme consists of a stepwise approach of escalating treatments: medical management (steps 0-1), pelvic floor physiotherapy, biofeedback and transanal irrigation (step 2), sacral nerve neuromodulation (step 3), percutaneous endoscopic caecostomy and anterograde enema (step 4) and definitive colostomy (step 5). METHODS: A pilot study was undertaken to assess the feasibility of collecting LARS data routinely with the parallel implementation of the BOREAL programme. All patients who underwent total mesorectal excision for rectal cancer between February 2017 and March 2019 were included. LARS was assessed using the LARS score and the Wexner Faecal Incontinence score at 30 days and 3, 6, 9 and 12 months postoperatively. A good functional result was considered to be a combined LARS score <20 and/or a Wexner score <4. RESULTS: In all, 137 patients were included. Overall compliance with the BOREAL programme was 72.9%. Major LARS decreased from 48% at 30 days postoperatively to 12% at 12 months, with a concomitant improvement in overall good function from 33% to 77%, P < 0.001. The majority of patients (n = 106, 77%) required medical management of their LARS. CONCLUSION: The BOREAL programme demonstrates the acceptability, feasibility and effectiveness of implementing a responsive, stepwise programme for detecting and treating LARS.

Regenerative medicine for digestive fistulae therapy: Benefits, challenges and promises of stem/stromal cells and emergent perspectives via their extracellular vesicles.

Despite current management strategies, digestive fistulae remain extremely debilitating complications associated with significant morbidity and mortality, generating a need to develop innovative therapies in these indications. A number of clinical trials and experimental studies have thus investigated the potential of stem/stromal cells (SCs) or SC-derived extracellular vesicles (EVs) administration for post-surgical and Crohn's-associated fistulae. This review summarizes the physiopathology and current standards-of-care for digestive fistulae, along with relevant evidence from animal and clinical studies regarding SC or EV treatment for post-surgical digestive fistulae. Additionally, existing preclinical models of fistulizing Crohn's disease and results of SC therapy trials in this indication will be presented. The optimal formulation and administration protocol of SC therapy products for gastrointestinal fistula treatment and the challenges for a widespread use of darvadstrocel (Alofisel) in clinical practice will be discussed. Finally, the potential advantages of EV therapy and the obstacles towards their clinical translation will be introduced.

A predictive score of inadequate bowel preparation based on a self-administered questionnaire: PREPA-CO.

INTRODUCTION: Inadequate bowel preparation before colonoscopy has a 20-30% rate and impedes on the quality of the procedure. The aim of this study was to develop a predictive score of inadequate bowel preparation, using a patient questionnaire on potential risk factors. METHODS: In this single center study, consecutive patients with colonoscopy indication were enrolled. The primary outcome was inadequate bowel preparation defined by Boston Bowel Preparation Scale (BBPS) score <7 or a score ≤1 in any of the 3 colonic segments. RESULTS: A total of 561 patients were included. Inadequate bowel preparation was seen in 25.0% of cases. Seven risk factors were selected into the prediction model of inadequate bowel preparation: diabetes or obesity, irregular physical activity, cirrhosis, use of antidepressants or neuroleptics, use of opiate medication, history of surgery and history of inadequate bowel preparation. The risk score, named PREPA-CO, had an AUROC of 0.621, adequately predicted bowel cleanliness in 68.3% of cases, with a specificity of 75.8% and a negative predictive value of 80.8%. CONCLUSION: We developed a predictive score named "Prepa-Co", allowing the identification of patients at high risk of inadequate bowel preparation. In clinical practice, this score could help tailor the prescription of the preparation to the patient.

Including Ratio of Platelets to Liver Stiffness Improves Accuracy of Screening for Esophageal Varices That Require Treatment.

BACKGROUND & AIMS: Based on platelets and liver stiffness measurements, the Baveno VI criteria (B6C), the expanded B6C (EB6C), and the ANTICIPATE score can be used to rule out varices needing treatment (VNT) in patients with compensated chronic liver disease. We aimed to improve these tests by including data on the ratio of platelets to liver stiffness. METHODS: In a retrospective analysis of data from 10 study populations, collected from 2004 through 2018, we randomly assigned data from 2368 patients with chronic liver disease of different etiologies to a derivation population (n = 1579; 15.1% with VNT, 50.2% with viral hepatitis, 28.9% with nonalcoholic fatty liver disease, 20.8% with alcohol-associated liver disease, with model for end-stage liver disease scores of 9.5 ± 3.0, and 93.0% with liver stiffness measurements ≥10 kPa) or a validation population (n = 789). Test results were compared with results from a sequential algorithm (VariScreen). VariScreen incorporated data on platelets or liver stiffness measurements and then the ratio of platelets to liver stiffness measurement, adjusted for etiology, patient sex, and international normalized ratio. RESULTS: In the derivation population, endoscopies were spared for 23.9% of patients using the B6C (VNT missed in 2.9%), 24.3% of patients using the ANTICIPATE score (VNT missed in 4.6%), 34.5% of patients using VariScreen (VNT missed in 2.9%), and 41.9% of patients using the EB6C (VNT missed in 10.9%). Differences in spared endoscopy rates were significant (P ≤ .001), except for B6C vs ANTICIPATE and in missed VNT only for EB6C vs the others (P ≤ .009). VariScreen was the only safe test regardless of sex or etiology (missed VNT ≤5%). Moreover, VariScreen secured screening without missed VNT in patients with model for end-stage liver disease scores higher than 10. This overall strategy performed better than a selective strategy restricted to patients with compensated liver disease. Test performance and safety did not differ significantly among populations. CONCLUSIONS: In a retrospective study of data from 2368 patients with chronic liver disease, we found that the B6C are safe whereas the EB6C are unsafe, based on missed VNT. The VariScreen algorithm performed well in patients with chronic liver disease of any etiology or severity. It is the only test that safely rules out VNT and can be used in clinical practice.

Enhancing digestive fistula healing by the off-label use of a thermoresponsive vessel occluder polymer associated with esophageal stent placement: A case report.

This case report relates to the first-in-man use of a vessel occluder gel medical device as a fistula occluder in a repurposing strategy. A patient with chronic colocutaneous fistula received an off-label treatment with a thermoresponsive Poloxamer 407 gel (20%) via percutaneous administration and injected under endoscopic control. Treatment consisted in the association of esophageal stent placement and gel injection. The product was administered just after the stent placement at<20°C in its liquid form, gelling at body temperature to form a fistula plug. However, the stent was removed at day 26 because of major pain and the fistula was still present. Treatment was continued a total of 14 administrations of thermoresponsive Poloxamer 407 gel during 7 weeks via the external fistula orifice. The treatment reduced fistula orifice diameter from 4.0±0.5 to 1mm and fistula daily output decreased from 425±65 to 23±4mL, when comparing the months before and after treatment. Gel administration was not associated with any toxic effects. The therapeutic outcome remained stable 1 year after treatment. The external fistula diameter and the fistula output were similar to what was observed after the last Poloxamer 407 gel administration.

Local administration of stem cell-derived extracellular vesicles in a thermoresponsive hydrogel promotes a pro-healing effect in a rat model of colo-cutaneous post-surgical fistula.

Extracellular vesicles (EVs), especially from stem/stromal cells (SCs), represent a cell-free alternative in regenerative medicine holding promises to promote tissue healing while providing safety and logistic advantages in comparison to cellular counterparts. Herein, we hypothesize that SC EVs, administered locally in a thermoresponsive gel, is a therapeutic strategy for managing post-surgical colo-cutaneous fistulas. This disease is a neglected and challenging condition associated to low remission rates and high refractoriness. Herein, EVs from a murine SC line were produced by a high-yield scalable method in bioreactors. The post-surgical intestinal fistula model was induced via a surgical cecostomy communicating the cecum and the skin in Wistar rats. Animals were treated just after cecostomy with PBS, thermoresponsive Pluronic F-127 hydrogel alone or containing SC EVs. A PET-monitored biodistribution investigation of SC EVs labelled with 89Zr was performed. Fistula external orifice and output assessment, probe-based confocal laser endomicroscopy, MRI and histology were carried out for therapy follow-up. The relevance of percutaneous EV administration embedded in the hydrogel vehicle was indicated by the PET-biodistribution study. Local administration of SC EVs in the hydrogel reduced colo-cutaneous fistula diameter, output, fibrosis and inflammation while increasing the density of neo-vessels when compared to the PBS and gel groups. This multi-modal investigation pointed-out the therapeutic potential of SC EVs administered locally and in a thermoresponsive hydrogel for the management of challenging post-surgical colon fistulas in a minimally-invasive cell-free strategy.