Hereditary Colorectal Cancer and Polyposis Syndromes Caused by Variants in Uncommon Genes.

A substantial number of hereditary colorectal cancer (CRC) and colonic polyposis cannot be explained by alteration in confirmed predisposition genes, such as mismatch repair (MMR) genes, APC and MUTYH. Recently, a certain number of potential predisposition genes have been suggested, involving each a small number of cases reported so far. Here, we describe the detection of rare variants in the NTLH1, AXIN2, RNF43, BUB1, and TP53 genes in nine unrelated patients who were suspected for inherited CRC and/or colonic polyposis. Seven of them were classified as pathogenic or likely pathogenic variants (PV/LPV). Clinical manifestations of carriers were largely consistent with reported cases with, nevertheless, distinct characteristics. PV/LPV in these uncommon gene can be responsible for up to 2.7% of inherited CRC or colonic polyposis syndromes. Our findings provide supporting evidence for the role of these genes in cancer predisposition, and contribute to the determination of related cancer spectrum and cancer risk for carriers, allowing for the establishment of appropriate screening strategy and genetic counseling in affected families.

Deciphering the clinical spectrum of gastric disease in patients with Juvenile Polyposis Syndrome.

BACKGROUND AND AIMS: Juvenile Polyposis Syndrome (JPS) is a rare hereditary autosomal dominant cancer-predisposition syndrome caused by germline pathogenic variants (PV) located in SMAD4 or BMPR1A genes. Precise clinical and endoscopic presentation as the evolution of gastric lesions remain ill-known. METHODS: Clinical, endoscopic, genetic, pathological data from patients with SMAD4 or BMPR1A PVs included between 2007 and 2020 in the French network on rare digestive polyposis (RENAPOL) database were prospectively collected to address uncertainties regarding gastric involvement. RESULTS: Thirty-six patients were included: 25 (69.5%) had SMAD4 PVs, 11 had BMPR1A PVs. For SMAD4 PV carriers, median age at inclusion was 43.0 years [range 10-78]. At baseline esophagogastroduodenoscopy (EGD), 22/25 (88%) exhibited at least one gastric juvenile polyp, 5/25 (20%) had macroscopic signs of inflammatory gastritis. Early gastric disease was mostly located under the cardia, then progressed to gastric antrum and body. During a mean follow-up period of 55.0 months, 12/25 had gastric disease progression (i.e. new juvenile polyps (91.6%), diffuse gastric involvement (41.6%), inflammatory flat progression (25%)). Among 62 biopsies, low-grade dysplasia was observed in 5 (7.5%) samples from 2 patients. Nine carriers (36%) underwent gastrectomy (mean age of 47.2 years) due to diffuse gastric involvement or worsening clinical symptoms. Gastric adenocarcinoma (T1) was found in one gastrectomy specimen. Among the 11 patients with BMPR1A PVs, 2 had gastric hamartomatomas at baseline EGD, none with dysplasia or symptoms. CONCLUSION: Gastric involvement in JPS appears to be progressive during life, initiating in the cardia area, and mostly concerns SMAD4 PV carriers.

Phenotypic characterisation of SMAD4 variant carriers.

BACKGROUND: Both hereditary haemorrhagic telangiectasia (HHT) and juvenile polyposis syndrome (JPS) are known to be caused by SMAD4 pathogenic variants, with overlapping symptoms for both disorders in some patients. Additional connective tissue disorders have also been reported. Here, we describe carriers of SMAD4 variants followed in an HHT reference centre to further delineate the phenotype. METHODS: Observational study based on data collected from the Clinical Investigation for the Rendu-Osler Cohort database. RESULTS: Thirty-three participants from 15 families, out of 1114 patients with HHT, had an SMAD4 variant (3%).Regarding HHT, 26 out of 33 participants (88%) had a definite clinical diagnosis based on Curaçao criteria. Complication frequencies were as follows: epistaxis (n=27/33, 82%), cutaneous telangiectases (n=19/33, 58%), pulmonary arteriovenous malformations (n=17/32, 53%), hepatic arteriovenous malformations (AVMs) (n=7/18, 39%), digestive angiodysplasia (n=13/22, 59%). No cerebral AVMs were diagnosed.Regarding juvenile polyposis, 25 out of 31 participants (81%) met the criteria defined by Jass et al for juvenile polyposis syndrome. Seven patients (21%) had a prophylactic gastrectomy due to an extensive gastric polyposis incompatible with endoscopic follow-up, and four patients (13%) developed a digestive cancer.Regarding connective tissue disorders, 20 (61%) had at least one symptom, and 4 (15%) participants who underwent echocardiography had an aortic dilation. CONCLUSION: We describe a large cohort of SMAD4 variant carriers in the context of HHT. Digestive complications are frequent, early and diffuse, justifying endoscopy every 2 years. The HHT phenotype, associating pulmonary and hepatic AVMs, warrants systematic screening. Connective tissue disorders broaden the phenotype associated with SMAD4 gene variants and justify systematic cardiac ultrasound and skeletal complications screening.

Impact of Endoscopic Treatment in Severe Duodenal Polyposis: A National Study in Familial Adenomatous Polyposis Patients.

BACKGROUND & AIMS: The majority of patients with familial adenomatous polyposis (FAP) develop duodenal adenomas with a risk of progression to duodenal cancer. Endoscopic management of FAP duodenal adenomas has been proposed as a less-invasive option than surgery, but available data still are limited. Our aims were to assess the feasibility and safety of endoscopic treatment in duodenal polyposis and to evaluate its long-term efficacy in terms of recurrence and malignant degeneration. METHODS: FAP patients with stage IV duodenal polyposis were enrolled in 5 French centers as part of a national cohort and followed up for a median period of 5.66 years (interquartile range, 6.39 y). Primary outcomes were duodenal surgery-free and cancer-free survival. Two groups of patients were identified according to endoscopic procedures: group 1: resection and or destruction (by argon plasma coagulation) of duodenal polyps, and group 2: papillectomy. RESULTS: Fifty-eight patients were enrolled (29 men; median age, 44 y). Endoscopic therapy was performed in 37 patients in group 1 and in 19 patients in group 2. Duodenal cancer-free and surgery-free survival were 95.8% at 5 years and 92.6% at 10 years. Four patients required surgery and 2 patients developed cancers. In the 58 patients, the calculated Spigelman score decreased from 9.24 points at entry to 6.35 at 5 years and then plateaued. Complications (mostly bleeding and perforation) occurred in 20 patients. CONCLUSIONS: In this long-term cohort follow-up evaluation, endoscopic treatment of patients with severe duodenal polyposis appears relatively safe and effective as an alternative to surgery for the prevention of cancer.

Updates in the diagnosis and management of non-ampullary small-bowel polyposis.

Advances in endoscopic instruments and techniques changed the strategy of diagnosis and management for non-ampullary small-bowel polyposis. In patients with Peutz-Jeghers syndrome, gastrointestinal surveillance using capsule endoscopy should commence no later than eight years old. Small bowel polyps >15 mm should be treated to prevent intussusception. Recently, endoscopic ischemic polypectomy and endoscopic reduction of intussusception were described. In patients with familial adenomatous polyposis, the first endoscopic screening using a lateral viewing and a longer endoscope to check the proximal jejunum should be performed around 25 years. Some experts recommend a first duodenal examination with a first colonoscopy (13 years). The surveillance intervals for duodenal polyposis should be adjusted individually. ESGE recommended the resection of every adenoma larger than 1 cm. Cold snare polypectomy has the potential to change the threshold of size for endoscopic resection. In patients with Juvenile polyposis syndrome, small bowel involvement seems infrequent and mostly located in the duodenal part. There is no indication for distal small bowel investigation.

Coordinated prospective follow-up of Lynch syndrome is able to detect the majority of incident cancers.

BACKGROUND: Lynch syndrome is one of the most common genetic predispositions to many cancers, most of which do not have a consensus recommendation for screening. AIMS: We studied in our region the value of a systematized and coordinated follow-up program for patients with Lynch syndrome on all organs at risk. METHODS: A multicenter prospective cohort evaluation was performed, from January 2016 to June 2021. RESULTS: One hundred and seventy-eight patients were prospectively included (104 women (58%), median age 44 years, range 35-56 years) with a median follow-up of 4 years (range 2.5-5 years), corresponding to a total of 652 patient-years. The overall cancer incidence rate was 13.80 per 1000 patient-years. Seven of nine cancers (78%) were detected during the follow-up program, with all cancers identified at an early stage. The detection rate of adenomas during colonoscopies was 24%. CONCLUSION: These preliminary data suggest that coordinated prospective follow-up of Lynch syndrome is capable of detecting the majority of incident cancers, particularly for locations not covered by an international follow-up recommendation. However, these results need to be confirmed by larger-scale studies.

Personalized endoscopic surveillance and intervention protocols for patients with familial adenomatous polyposis: the European FAP Consortium strategy.

Background and study aims Patients with familial adenomatous polyposis (FAP) undergo colectomy and lifelong endoscopic surveillance to prevent colorectal, duodenal and gastric cancer. Endoscopy has advanced significantly in recent years, including both detection technology as well as treatment options. For the lower gastrointestinal tract, current guidelines do not provide clear recommendations for surveillance intervals. Furthermore, the Spigelman staging system for duodenal polyposis has its limitations. We present a newly developed personalized endoscopic surveillance strategy for the lower and upper gastrointestinal tract, aiming to improve the care for patients with FAP. We aim to inform centers caring for FAP patients and encourage the discussion on optimizing endoscopic surveillance and treatment in this high-risk population. Methods The European FAP Consortium, consisting of endoscopists with expertise in FAP, collaboratively developed new surveillance protocols. The proposed strategy was consensus-based and a result of several consortium meetings, discussing current evidence and limitations of existing systems. This strategy provides clear indications for endoscopic polypectomy in the rectum, pouch, duodenum and stomach and defines new criteria for surveillance intervals. This strategy will be evaluated in a 5-year prospective study in nine FAP expert centers in Europe. Results We present a newly developed personalized endoscopic surveillance and endoscopic treatment strategy for patients with FAP aiming to prevent cancer, optimize endoscopic resources and limit the number of surgical interventions. Following this new strategy, prospectively collected data in a large cohort of patients will inform us on the efficacy and safety of the proposed approaches.

Small-bowel capsule endoscopy and device-assisted enteroscopy for diagnosis and treatment of small-bowel disorders: European Society of Gastrointestinal Endoscopy (ESGE) Guideline - Update 2022.

MR1: ESGE recommends small-bowel capsule endoscopy as the first-line examination, before consideration of other endoscopic and radiological diagnostic tests for suspected small-bowel bleeding, given the excellent safety profile of capsule endoscopy, its patient tolerability, and its potential to visualize the entire small-bowel mucosa.Strong recommendation, moderate quality evidence. MR2: ESGE recommends small-bowel capsule endoscopy in patients with overt suspected small-bowel bleeding as soon as possible after the bleeding episode, ideally within 48 hours, to maximize the diagnostic and subsequent therapeutic yield.Strong recommendation, high quality evidence. MR3: ESGE does not recommend routine second-look endoscopy prior to small-bowel capsule endoscopy in patients with suspected small-bowel bleeding or iron-deficiency anemia.Strong recommendation, low quality evidence. MR4: ESGE recommends conservative management in those patients with suspected small-bowel bleeding and high quality negative small-bowel capsule endoscopy.Strong recommendation, moderate quality evidence. MR5: ESGE recommends device-assisted enteroscopy to confirm and possibly treat lesions identified by small-bowel capsule endoscopy.Strong recommendation, high quality evidence. MR6: ESGE recommends the performance of small-bowel capsule endoscopy as a first-line examination in patients with iron-deficiency anemia when small bowel evaluation is indicated.Strong recommendation, high quality evidence. MR7: ESGE recommends small-bowel capsule endoscopy in patients with suspected Crohn's disease and negative ileocolonoscopy findings as the initial diagnostic modality for investigating the small bowel, in the absence of obstructive symptoms or known bowel stenosis.Strong recommendation, high quality evidence. MR8: ESGE recommends, in patients with unremarkable or nondiagnostic findings from dedicated small-bowel cross-sectional imaging, small-bowel capsule endoscopy as a subsequent investigation if deemed likely to influence patient management.Strong recommendation, low quality evidence. MR9: ESGE recommends, in patients with established Crohn's disease, the use of a patency capsule before small-bowel capsule endoscopy to decrease the capsule retention rate.Strong recommendation, moderate quality evidence. MR10: ESGE recommends device-assisted enteroscopy (DAE) as an alternative to surgery for foreign bodies retained in the small bowel requiring retrieval in patients without acute intestinal obstruction.Strong recommendation, moderate quality evidence. MR11: ESGE recommends DAE-endoscopic retrograde cholangiopancreatography (DAE-ERCP) as a first-line endoscopic approach to treat pancreaticobiliary diseases in patients with surgically altered anatomy (except for Billroth II patients).Strong recommendation, moderate quality evidence.

AXIN2 germline testing in a French cohort validates pathogenic variants as a rare cause of predisposition to colorectal polyposis and cancer.

Only a few patients with germline AXIN2 variants and colorectal adenomatous polyposis or cancer have been described, raising questions about the actual contribution of this gene to colorectal cancer (CRC) susceptibility. To assess the clinical relevance for AXIN2 testing in patients suspected of genetic predisposition to CRC, we collected clinical and molecular data from the French Oncogenetics laboratories analyzing AXIN2 in this context. Between 2004 and June 2020, 10 different pathogenic/likely pathogenic AXIN2 variants were identified in 11 unrelated individuals. Eight variants were from a consecutive series of 3322 patients, which represents a frequency of 0.24%. However, loss-of-function AXIN2 variants were strongly associated with genetic predisposition to CRC as compared with controls (odds ratio: 11.89, 95% confidence interval: 5.103-28.93). Most of the variants were predicted to produce an AXIN2 protein devoid of the SMAD3-binding and DIX domains, but preserving the ß-catenin-binding domain. Ninety-one percent of the AXIN2 variant carriers who underwent colonoscopy had adenomatous polyposis. Forty percent of the variant carriers developed colorectal or/and other digestive cancer. Multiple tooth agenesis was present in at least 60% of them. Our report provides further evidence for a role of AXIN2 in CRC susceptibility, arguing for AXIN2 testing in patients with colorectal adenomatous polyposis or cancer.

Juvenile polyposis: Focus on less described manifestations.

Juvenile polyposis represents an heterogeneous disease as different genetic dominant backgrounds have been evidenced leading to different clinical presentations. It is associated in some patients with a different syndrome, Hereditary Hemorragic Telangiectasia, justifying a complementary and different management. Recent international recommendations help in managing this very rare disease, and this management should probably be restricted to expert centers able to take care of the multiple manifestations and risks of these patients and families. This paper will focus on the poorly known and evaluated aspects of juvenile polyposis, excluding the colonic involvement and epidemiology that are addressed in a different article of this issue.

Desmoid tumors located in the abdomen or associated with adenomatous polyposis: French intergroup clinical practice guidelines for diagnosis, treatment, and follow-up (SNFGE, FFCD, GERCOR, UNICANCER, SFCD, SFED, SFRO, ACHBT, SFR).

INTRODUCTION: Desmoid tumor (DT) of the abdomen is a challenging and rare disease. The level of evidence available to document their treatment is relatively low, however, recent publications of prospective studies have allowed to precise their management. METHODS: This document is a summary of the French intergroup guidelines realized by all French medical and surgical societies involved in the management of DT located in the abdomen or associated with adenomatous polyposis. Recommendations are graded in four categories (A, B, C and D), according to the level of evidence found in the literature until January 2021. RESULTS: When the diagnosis of DT is suspected a percutaneous biopsy should be performed when possible. A molecular analysis looking for pathogenic mutations of the CTNNB1 and APC genes should be systematically performed. When a somatic pathogenic variant of the APC gene is present, an intestinal polyposis should be searched. Due to a high rate of spontaneous regression, non-complicated DT should first benefit from an active surveillance with MRI within 2 months after diagnosis to assess the dynamic of tumor growth. The treatment decision must be discussed in an expert center, favoring the less toxic treatments which can include broad spectrum tyrosine kinase inhibitor or conventional chemotherapy (methotrexate-vinblastine). Surgery, outside the context of emergency, should only be considered for favorable location in an expert center. CONCLUSION: French guidelines for DT management were elaborated to help offering the best personalized therapeutic strategy in daily clinical practice as the DT therapeutic landscape is complexifying. Each individual case must be discussed within a multidisciplinary expert team.

Digestive perforations related to endoscopy procedures: a local management charter based on local evidence and experts' opinion.

Background and study aims Perforations are a known adverse event of endoscopy procedures; a proposal for appropriate management should be available in each center as recommended by the European Society of Gastrointestinal Endoscopy. The objective of this study was to establish a charter for the management of endoscopic perforations, based on local evidence. Patients and methods Patients were included if they experienced partial or complete perforation during an endoscopic procedure between 2008 and 2018 (retrospectively until 2016, then prospectively). Perforations (size, location, closure) and management (imagery, antibiotics, surgery) were analyzed. Using these results, a panel of experts was asked to propose a consensual management charter. Results A total of 105 patients were included. Perforations occurred mainly during therapeutic procedures (91, 86.7%). Of the perforations, 78 (74.3 %) were diagnosed immediately and managed during the procedure; 69 of 78 (88.5 %) were successfully closed. Closures were more effective during therapeutic procedures (60 of 66, 90.9 %) than during diagnostic procedures (9 of 12, 75.0 %, P  = 0.06). Endoscopic closure was effective for 37 of 38 perforations (97.4 %) < 0.5 cm, and for 26 of 34 perforations (76.5 %) ≥ 0.5 cm ( P  < 0.05). For perforations < 0.5 cm, systematic computed tomography (CT) scan, antibiotics, or surgical evaluation did not improve the outcome. Four of 105 deaths (3.8 %) occurred after perforation, one of which was attributable to the perforation itself. Conclusions Detection and closure of perforations during endoscopic procedure had a better outcome compared to delayed perforations; perforations < 0.5 cm had a very good prognosis and CT scan, surgeon evaluation, or antibiotics are probably not necessary when the endoscopic closure is confidently performed. This work led to proposal of a local management charter.

Motorized spiral enteroscopy: results of an international multicenter prospective observational clinical study in patients with normal and altered gastrointestinal anatomy.

BACKGROUND : Motorized spiral enteroscopy (MSE) has been shown to be safe and effective for deep enteroscopy in studies performed at expert centers with limited numbers of patients without previous abdominal surgery. This study aimed to investigate the safety, efficacy, and learning curve associated with MSE in a real-life scenario, with the inclusion of patients after abdominal surgery and with altered anatomy. METHODS : Patients with indications for deep enteroscopy were enrolled in a prospective observational multicenter study. The primary objective was the serious adverse event (SAE) rate; secondary objectives were the diagnostic and therapeutic yield, procedural success, time, and insertion depth. Data analysis was subdivided into training and core (post-training) study phases at centers with different levels of MSE experience. RESULTS : 298 patients (120 women; median age 68, range 19-92) were enrolled. In the post-training phase, 21.5 % (n = 54) had previous abdominal surgery, 10.0 % (n = 25) had surgically altered anatomy. Overall, SAEs occurred in 2.3 % (7/298; 95 %CI 0.9 %-4.8 %). The SAE rate was 2.0 % (5/251) in the core group and 4.3 % (2/47) in the training group, and was not increased after abdominal surgery (1.9 %). Total enteroscopy was achieved in half of the patients (n = 42) undergoing planned total enteroscopy. In 295/337 procedures (87.5 %), the anatomical region of interest could be reached. CONCLUSIONS : This prospective multicenter study showed that MSE was feasible and safe in a large cohort of patients in a real-life setting, after a short learning curve. MSE was shown to be feasible in postsurgical patients, including those with altered anatomy, without an increase in the SAE rate.

Endoscopic characterization of colorectal neoplasia with different published classifications: comparative study involving CONECCT classification.

Background and study aims The aim of this study was to validate the COlorectal NEoplasia Classification to Choose the Treatment (CONECCT) classification that groups all published criteria (including covert signs of carcinoma) in a single table. Patients and methods For this multicenter comparative study an expert endoscopist created an image library (n = 206 lesions; from hyperplastic to deep invasive cancers) with at least white light Imaging and chromoendoscopy images (virtual ± dye based). Lesions were resected/biopsied to assess histology. Participants characterized lesions using the Paris, Laterally Spreading Tumours, Kudo, Sano, NBI International Colorectal Endoscopic Classification (NICE), Workgroup serrAted polypS and Polyposis (WASP), and CONECCT classifications, and assessed the quality of images on a web-based platform. Krippendorff alpha and Cohen's Kappa were used to assess interobserver and intra-observer agreement, respectively. Answers were cross-referenced with histology. Results Eleven experts, 19 non-experts, and 10 gastroenterology fellows participated. The CONECCT classification had a higher interobserver agreement (Krippendorff alpha = 0.738) than for all the other classifications and increased with expertise and with quality of pictures. CONECCT classification had a higher intra-observer agreement than all other existing classifications except WASP (only describing Sessile Serrated Adenoma Polyp). Specificity of CONECCT IIA (89.2, 95 % CI [80.4;94.9]) to diagnose adenomas was higher than the NICE2 category (71.1, 95 % CI [60.1;80.5]). The sensitivity of Kudo Vi, Sano IIIa, NICE 2 and CONECCT IIC to detect adenocarcinoma were statistically different ( P  < 0.001): the highest sensitivities were for NICE 2 (84.2 %) and CONECCT IIC (78.9 %), and the lowest for Kudo Vi (31.6 %). Conclusions The CONECCT classification currently offers the best interobserver and intra-observer agreement, including between experts and non-experts. CONECCT IIA is the best classification for excluding presence of adenocarcinoma in a colorectal lesion and CONECCT IIC offers the better compromise for diagnosing superficial adenocarcinoma.