How to suspect the presence of high-risk esophageal varices and when to start endoscopic surveillance in children with biliary atresia?

BACKGROUND AND AIM: Portal hypertension determines the outcome of children with biliary atresia (BA) and is common even after a successful Kasai portoenterostomy (KPE). However, there are no clear-cut guidelines on the age of starting surveillance and the modality (endoscopy vs non-invasive tests [NITs]). In this cohort study, we analyzed our database to find out the utility of NITs in detecting high-risk esophageal varices in BA. METHODS: From June 2010 to May 2022, consecutive children of BA who underwent upper gastrointestinal (UGI) endoscopy were included. Esophageal varices were classified as high-risk (grade II with red-color signs or grade III or IV irrespective of red-color signs. NITs such as splenomegaly (clinical and USG), platelet count, aspartate transaminase to platelet ratio index (APRI), and platelet-to-spleen diameter ratio were compared between cases with high-risk and low-risk varices. RESULTS: A total of 110 children, 75 boys (66 successful KPE and 44 failed/KPE not performed) were enrolled. The median age at KPE was 85 days (IQR 63-98). Thirteen (11.8%) children presented with UGI bleeding. The first endoscopy revealed gastroesophageal varices in 75.4% of cases, and 32% of them had high-risk varices. Multivariate analysis revealed failed KPE, history of UGI bleeding, bigger spleen size (> 3.5 cm), lower platelet count (< 150 000), and higher APRI (> 2) are independent predictors of the presence of high-risk esophageal varices. CONCLUSION: Endoscopy is the best in predicting the presence of high-risk varices that might bleed; hence, early surveillance endoscopy should be started in children with splenomegaly, thrombocytopenia, and high APRI score to prevent variceal bleeding.

Chronological Changes in Mucosal Deformity by Endoscopic Suturing after Gastric Endoscopic Submucosal Dissection: A Multicenter Retrospective Analysis.

INTRODUCTION: Endoscopic suturing of a mucosal defect is expected to prevent postoperative bleeding after endoscopic submucosal dissection (ESD). Endoscopic suturing causes mucosal deformity, which may interfere with endoscopic surveillance thereafter. We retrospectively investigated long-term chronological changes in mucosal suturing by endoscopic suturing. METHODS: Forty-three patients who underwent endoscopic hand suturing (EHS) after gastric ESD at three institutions were enrolled. First, our hypothesis that the suturing sites healed via inflammation, disappearance of mucosal inversion, and flattening was validated. Subsequently, the duration required to reach each healing step was evaluated. RESULTS: A total of 137 follow-up endoscopies were assessed, in which all cases showed the hypothesized chronological course on the suturing sites. The 95th percentiles of the duration when showing the disappearance of the inflammatory change and the inverted change were 63 days and 15.5 months after the procedure, respectively. DISCUSSION/CONCLUSION: The data show that the mucosal deformity induced by EHS disappeared within 16 months. Endoscopic suturing is thus considered to have a negligible effect on endoscopic surveillance following the procedure.

Risk and prognostic factors of invasive gastric cancer detection during surveillance endoscopy: Multi-institutional cross-sectional study.

OBJECTIVES: Esophagogastroduodenoscopy (EGD) is important for the detection of curable gastric cancer (GC). However, there are no appropriate surveillance data during routine endoscopic inspections. This study aimed to clarify the risk factors of pT1b or deeper GC detection during surveillance endoscopy. METHODS: This was a retrospective, multicenter, cross-sectional study conducted in 15 Japanese hospitals. We retrospectively analyzed patients with GC who had previously undergone surveillance endoscopy at each institution from January 2014 to March 2020. Patients who had undergone gastrectomy, non-infection of Helicobacter pylori (Hp), and those with intervals <3 months or >10 years from a previous endoscopy were excluded. RESULTS: In total, 1085 patients with GCs detected during surveillance endoscopy were enrolled. The multivariate logistic analysis revealed that current Hp infection (odds ratio [OR] 2.18; 95% confidence interval [CI] 1.50-3.16) and a surveillance interval of >1.5 years (OR 1.96; 95% CI 1.35-2.84) were independent risk factors for pT1b or deeper GC. The 5-year disease-specific survival (5y-DSS) rate of GC was significantly lower in patients with surveillance interval of >1.5 years than in those with surveillance interval of ≤1.5 years (93.7% vs. 98.3%, P < 0.001). Similarly, the 5y-DSS rate of GC was significantly lower in patients with active Hp infection than in those without (93.7% vs. 99.4%, P < 0.001). CONCLUSION: In this study, a surveillance interval of >1.5 years and current Hp infection were independent risk factors for detecting pT1b or deeper GC. Additionally, these factors were poor prognostic factors of the detected GC during surveillance endoscopy.

Young people's experiences of a CDH1 pathogenic variant: Decision-making about gastric cancer risk management.

The most effective option for gastric cancer risk management in individuals with a CDH1 germline pathogenic or likely pathogenic variant (PV) in Australia is prophylactic total gastrectomy (PTG). There is, however, increasing confidence in endoscopic surveillance as a risk management strategy thus affording individuals with a CDH1 PV with challenging decisions regarding their gastric cancer risk management. For young people, this decision-making comes at a complex development stage of emerging and young adulthood. This study aims to explore the factors that influence young people's decision-making about their gastric cancer risk management due to a CDH1 PV. Potential participants were identified and approached through the Parkville Familial Cancer Centre in Melbourne, Australia. Thematic analysis was used to interpret and analyze the data. Qualitative interviews were conducted with 13 people with a CDH1 PV aged 18 to 39 years, inclusive. The interviews found that participants' familial and shared experiences of cancer and risk management, perceived tolerance of uncertainty, and desire for control over their cancer risk were fundamental in their decision-making about their gastric cancer risk management. The participants' young adult life stage was also deemed particularly important in decisions about the timing of PTG. The findings of this study are vital to inform decisional counseling discussions with this unique population.

Intensive surveillance endoscopy for multiple gastrointestinal tumors in a patient with constitutional mismatch repair deficiency: case report.

BACKGROUND: Constitutional mismatch repair deficiency (CMMRD) is an extremely rare autosomal recessive hereditary disease characterized by the absence of mismatch repair gene activity from birth, which results in brain tumors, colonic polyposis, gastrointestinal cancers, and lymphomas later in life. An aggressive approach, including colectomy or proctocolectomy, is recommended for the treatment of colorectal cancer. Additionally, partial colectomy with subsequent endoscopic surveillance may be an alternative strategy due to poor patient's condition, although there is no evidence of surveillance endoscopy after partial colectomy for CMMRD. CASE PRESENTATION: A 13-year-old male patient with a history of T-lymphoblastic lymphoma underwent total gastrointestinal endoscopy, which revealed rectal cancer, colorectal polyposis, and duodenal adenoma. Differential diagnosis included constitutional mismatch repair deficiency according to its scoring system and microsatellite instability, and subsequent germline mutation testing for mismatch repair genes confirmed the diagnosis of constitutional mismatch repair deficiency based on a homozygous mutation in mutS homolog 6 (MSH6). The patient and his family refused colectomy due to the high risk of malignancies other than colorectal cancer, which could require radical surgery. Therefore, the patient underwent low anterior resection of the rectosigmoid colon for rectal cancer and intensive surveillance endoscopy for the remaining colon polyposis. During the 3-year period after initial surgery, 130 polyps were removed and the number of polyps gradually decreased during 6-months interval surveillance endoscopies, although only one polyp was diagnosed as invasive adenocarcinoma (pT1). CONCLUSIONS: Our experience of short surveillance endoscopy illustrates that this strategy might be one of options according to patient's condition.

Colorectal Cancer associated with pediatric inflammatory bowel disease: a case series.

BACKGROUND: Inflammatory bowel disease (IBD) is associated with an increased risk of Colorectal cancer (CRC), and its most important risk factors are the duration and extent of the disease. Pediatric-onset inflammatory bowel disease has a tendency for a more extensive, more severe, and longer predicted disease duration than adult-onset inflammatory bowel disease. This study aimed to identify the clinical characteristics of patients with CRC related to pediatric-onset IBD and consider the appropriateness of current surveillance endoscopy recommendations for the detection of premalignant lesions and early-stage CRC. METHODS: We searched a research platform based on the SUPREME electronic medical record data-mining system to identify cases of colorectal malignancy in patients with pediatric IBD that presented between 2000 and 2020. RESULTS: During the follow-up, 4 (1.29 per 1000 person years) out of 443 patients with PIBD was diagnosed with CRC. The median age at diagnosis of CRC was 18.5 (range: 15-24) years, and the median period from diagnosis of IBD to CRC was 9.42 (range: 0.44-11.96) years. The sigmoid colon was the most frequent location of CRC (in 3 of the 4 cases). Adenocarcinoma was the most common histological type (in 2 of the 4 cases). CONCLUSIONS: Patients with pediatric-onset IBD exhibited a much shorter disease duration than that of adult-onset IBD at the time of diagnosis of CRC, suggesting that surveillance endoscopy for the detection of precancerous lesions and early-stage cancer should be initiated earlier in pediatric patients than in adult patients.

Thermal Ablation of Mucosal Defect Margins Reduces Adenoma Recurrence After Colonic Endoscopic Mucosal Resection.

BACKGROUND & AIMS: Colorectal cancer (CRC) can be prevented by colonoscopy and polypectomy. Endoscopic mucosal resection (EMR) is performed to remove large laterally spreading colonic lesions that have a high risk of progression to CRC. Endoscopically invisible micro-adenomas at the margins of the EMR site might contribute to adenoma recurrence, which occurs in 15% to 30% of patients who undergo surveillance. We aimed to determine the efficacy of adjuvant thermal ablation of the EMR mucosal defect margin in reducing polyp recurrence. METHODS: We performed a prospective study of 390 patients with large laterally spreading colonic lesions (≥ 20 mm, n = 416) referred for EMR at 4 tertiary centers in Australia. After complete lesion excision by EMR, lesions were randomly assigned to thermal ablation of the post-EMR mucosal defect margin (n = 210) or no additional treatment (controls, n = 206). We performed surveillance colonoscopies with standardized photo documentation and biopsies of the scar after 5 to 6 months. Patient, procedure, and lesion characteristics were similar between the groups. The primary endpoint was detection of lesion recurrence at first surveillance colonoscopy. RESULTS: A significantly lower proportion of patients who received thermal ablation of the post-EMR mucosal defect margin had evidence of recurrence at first surveillance colonoscopy (10/192, 5.2%) than controls (37/176, 21.0%) (P < .001). The relative risk of recurrence in the thermal ablation group was 0.25 compared with the control group (95% confidence interval 0.13-0.48). Rates of adverse events were similar between the groups. CONCLUSIONS: In a multicenter randomized trial, thermal ablation of the post-EMR mucosal defect margin significantly reduced polyp recurrence at first surveillance colonoscopy, compared with no additional treatment. Routine implementation of this simple and safe technique could increase the utility of EMR, decrease surveillance burdens, and reduce morbidity and mortality from CRC. ClinicalTrials.gov no: NCT01789749.

Suboptimal Adherence in Clinical Practice to Guidelines Recommendation to Screen for Lynch Syndrome.

BACKGROUND: Identification of Lynch syndrome (LS) followed by annual/biannual surveillance colonoscopy markedly reduces the risk of developing new colorectal cancer (CRC) among those with LS. AIMS: (1) To determine the current practice of identifying LS in the USA and Canada, and current surveillance and management practices for those diagnosed with LS; (2) to determine whether variances in current practice are physician/region dependent or influenced by ease of access to specialist clinics. METHODS: An online survey request was sent to practicing gastroenterologists through the Canadian Association of Gastroenterology and the American College of Gastroenterology. Fisher's exact tests were performed to determine the factors associated with screening for LS and separately for follow-up, surveillance, and management. RESULTS: A total of 249 participants were recruited, of which 237 were gastroenterologists and included in the analysis. Less than one-third of practicing gastroenterologists indicated that their CRC patients were undergoing screening tests to identify LS. While 42% (65/153) of participants from the USA stated that their patients were undergoing universal LS screening (i.e., among all diagnosed with CRC), only 12% (6/49) of participants from Canada reported this practice (p < 0.001). There was no difference in reported practice between the physicians that do and do not have access to hereditary clinics (35% vs. 34% testing; p = 0.54). Appropriate surveillance interval to look for CRC in patients with LS was recommended by most. CONCLUSION: This survey suggests there is a significant difference in practice between Canada and the USA in regard to identification of LS, with suboptimal practice throughout North America.

Helicobacter pylori Eradication Does Not Adversely Affect the Clinical Course of Gastric Cancer: A Multicenter Study on Screening Endoscopic Examination in Japan.

BACKGROUND: Since gastric cancers (GCs) detected after Helicobacter pylori (HP) eradication present with different morphological characteristics from conventional HP-positive GCs, delayed detection of early-stage GCs may be observed. This study aimed to investigate the clinical impact of HP eradication on diagnosing GC during screening endoscopy. METHODS: Eleven health checkup institutions in Japan participated in the present study. All GC cases newly diagnosed by screening endoscopy between January 2016 and December 2020 were included. After propensity score matching, multivariable regression analysis was performed to estimate the effect of HP eradication on deep tumor invasion among HP-eradicated and HP-positive GC cases. RESULTS: A total of 231 patients with GCs (134 HP-eradicated and 97 HP-positive cases) were enrolled. After propensity score matching, there were 81 cases in each group. The distribution of the depth of tumor invasion (pT1a, pT1b1, pT1b2, and pT2) between the HP-eradicated group and HP-positive group was similar (p = 0.82). In the propensity analysis, with HP-positive as the reference value, HP eradication was not significantly associated with T1b-T4-GCs and T1b2-T4-GCs, with odds ratios (95% confidence intervals) of 1.16 (0.48-2.81) and 1.16 (0.42-3.19), respectively. CONCLUSIONS: HP eradication does not adversely affect the clinical course of GCs, supporting the recommendation of HP eradication in screening programs to reduce the total number of GC cases without delaying diagnosis.

360º optoacoustic capsule endoscopy at 50 Hz for esophageal imaging.

Gastrointestinal (GI) endoscopy is a common medical diagnostic procedure used for esophageal cancer detection. Current emerging capsule optoacoustic endoscopes, however, suffer from low pulse repetition rates and slow scanning units limit attainable imaging frame rates. Consequently, motion artifacts result in inaccurate spatial mapping and misinterpretation of data. To overcome these limitations, we report a 360º, 50 Hz frame rate, distal scanning capsule optoacoustic endoscope. The translational capability of the instrument for human GI tract imaging was characterized with an Archimedean spiral phantom consisting of twelve 100 µm sutures, a stainless steel mesh with a pitch of 3 mm and an ex vivo pig esophagus sample. We estimated an imaging penetration depth of ~0.84 mm in vivo by immersing the mesh phantom in intralipid solution to simulate light scattering in human esophageal tissue and validated our findings ex vivo using pig esophagus. This proof-of-concept study demonstrates the translational potential of the proposed video-rate endoscope for human GI tract imaging.

Familial and hereditary gastric cancer, an overview.

There are three major hereditable syndromes that affect primarily the stomach: hereditary diffuse gastric cancer (HDGC), gastric adenocarcinoma and proximal polyposis of the stomach (GAPPS) and familial intestinal gastric cancer (FIGC). HDGC is caused by germline mutations in CDH1 gene that occur in 10-40% of HDGC families and, in a minority of cases, by mutations in CTNNA1 gene. GAPPS is caused by germline mutations in the promoter 1B of APC gene, and the genetic cause of FIGC is not fully elucidated. Gastric cancer can also be observed as part of other inherited cancer disorders, namely in familial adenomatous polyposis, MUTYH-associated polyposis, Peutz-Jeghers syndrome, juvenile polyposis syndrome, Lynch syndrome, Li-Fraumeni syndrome, Cowden syndrome, and hereditary breast and ovarian cancer syndrome. In this article, the state of the art of familial gastric cancer regarding the clinical, molecular and pathology features is reviewed, as well as the practical aspects for a correct diagnosis and clinical management.

Cost-effectiveness of bariatric and metabolic surgery, and implications of COVID-19 in the United Kingdom.

BACKGROUND: People living with obesity have been among those most disproportionately impacted by the COVID-19 pandemic, highlighting the urgent need for increased provision of bariatric and metabolic surgery (BMS). OBJECTIVES: To evaluate the possible clinical and economic benefits of BMS compared with nonsurgical treatment options in the UK, considering the broader impact that COVID-19 has on people living with obesity. SETTING: Single-payer healthcare system (National Health Service, England). METHODS: A Markov model compared lifetime costs and outcomes of BMS and conventional treatment among patients with body mass index (BMI) ≥ 40 kg/m2, BMI ≥ 35 kg/m2 with obesity-related co-morbidities (Group A), or BMI ≥ 35 kg/m2 with type 2 diabetes (T2D; Group B). Inputs were sourced from clinical audit data and literature sources; direct and indirect costs were considered. Model outputs included costs and quality-adjusted life years (QALYs). Scenario analyses whereby patients experienced COVID-19 infection, BMS was delayed by five years, and BMS patients underwent endoscopy were conducted. RESULTS: In both groups, BMS was dominant versus conventional treatment, at a willingness-to-pay threshold of £25,000/QALY. When COVID-19 infections were considered, BMS remained dominant and, across 1000 patients, prevented 117 deaths, 124 hospitalizations, and 161 intensive care unit admissions in Group A, and 64 deaths, 65 hospitalizations, and 90 intensive care unit admissions in Group B. Delaying BMS by 5 years resulted in higher costs and lower QALYs in both groups compared with not delaying treatment. CONCLUSION: Increased provision of BMS would be expected to reduce COVID-19-related morbidity and mortality, as well as obesity-related co-morbidities, ultimately reducing the clinical and economic burden of obesity.

Differential cytokine and chemokine expression during rejection and infection following intestinal transplantation.

BACKGROUND/OBJECTIVES: Rejection and infectious enteritis in intestinal transplant (ITx) patients present with virtually identical symptoms. Currently, the gold standard for differentiating between these two conditions is endoscopy, which is invasive and costly. Our primary aim was to identify differences in peripheral blood cytokines during episodes of acute cellular rejection (ACR) and infectious enteritis in patients with intestinal transplants. METHODS: This was a prospective, cross-sectional study involving ITx patients transplanted between 2000 and 2016. We studied 63 blood samples collected from 29 ITx patients during periods of normal (n = 24) and abnormal (n = 17) allograft function. PBMCs from whole blood samples were cultured under unstimulated or stimulated conditions with phytohemagglutinin (PHA). The supernatant from these cultures were collected to measure cytokine and chemokine levels using a 38-plex luminex panel. RESULTS: Our study found that cytokines and chemokines are differentially expressed in normal, ACR, and infectious enteritis samples under unstimulated conditions based on heatmap analysis. Although each cohort displayed distinctive signatures, only MDC (p = 0.037) was found to be significantly different between ACR and infectious enteritis. Upon stimulation of PBMCs, patients with ACR demonstrated increased immune reactivity compared to infectious enteritis; though this did not reach statistical significance. CONCLUSIONS: To our knowledge, this is the first comprehensive study comparing cytokine expression during acute rejection and infectious enteritis in intestinal transplant recipients. Our results suggest that cytokines have the potential to be used as clinical markers for risk stratification and/or diagnosis of ACR and infectious enteritis.

Should Surveillance Endoscopy Be Routine After One Anastomosis Gastric Bypass to Detect Marginal Ulcers: Initial Outcomes in a Tertiary Referral Centre.

PURPOSE: Encouraged by the excellent outcomes of one anastomosis gastric bypass (OAGB) reported by many authors, we added this procedure to our bariatric armamentarium in 2015. Here we present our initial experience of 68 cases and findings from routine upper gastrointestinal endoscopy at 1 year. MATERIALS AND METHODS: This is a retrospective analysis of a prospectively maintained database of a single surgical unit in a tertiary referral centre. Patients undergoing OAGB from January 2015 to May 2019 were included. A fixed biliopancreatic (BP) limb length of 200 cm was used in all patients. Surveillance endoscopy was done at 1-year follow-up. RESULTS: Sixty-eight patients, of whom 67.6% were females, were analysed. Mean age was 40.8 ± 1 years. Mean preoperative weight and body mass index (BMI) were 131 ± 24.7 kg and 51 ± 7 kg/m2, respectively. Median follow-up was 23 months (range 9-55 months), with 88% follow-up at 6 months and 1 year. At 1 year, mean total weight loss (TWL) and excess weight loss (EWL) were 35% and 71%, respectively. Endoscopy at 1 year revealed a 9.5% rate of marginal ulcers, majority of which healed with conservative treatment. Eighty-eight percent patients had complete remission of diabetes, and 94% had complete remission of hypertension. There was no 30-day mortality. CONCLUSION: OAGB is a safe and effective bariatric procedure with excellent short-term outcomes in terms of weight loss, resolution of obesity-related co-morbidities and complications. Routine surveillance endoscopy at 1 year may detect asymptomatic marginal ulcers and, thus, prevent ulcer-related complications.

Splenic stiffness and platelet count to predict varices needing treatment in pediatric extrahepatic portal vein obstruction.

BACKGROUND: Surveillance endoscopy to detect varices needing treatment (VNT) is important to prevent bleeding and morbidity in portal hypertension. In adult and pediatric cirrhosis, platelet count and liver stiffness measurement (LSM) are useful in selecting patients for endoscopy. Such recommendations do not exist for extrahepatic portal vein obstruction (EHPVO). Splenic stiffness measurement (SSM) has been studied in adult and pediatric EHPVO with conflicting results and methodological errors. This study evaluates the role of platelet counts and SSM to predict VNT and bleeding in pediatric EHPVO while comparing LSM and SSM between pediatric EHPVO and controls. METHODS: One hundred and seven children (55 with EHPVO and 52 controls) were recruited. Clinical, biochemical, hematological, and radiographic parameters of all children were noted. All children with EHPVO underwent endoscopy. RESULTS: Of the 55 children with EHPVO, 48 (87.3%) had VNT. There was no difference in the platelet counts (85,000/mm3 vs. 120,000/mm3, p = 0.58) and SSM (3.62 vs. 3.19, p = 0.05) between EHPVO children with VNT and those without. They had poor sensitivity and specificity to predict VNT. EHPVO children with bleeding had higher SSM that those without. LSM was higher among EHPVO than among controls (1.19 vs. 1.10, p = 0.003). Those with LSM higher than controls had normal liver histology. CONCLUSION: SSM is higher in EHPVO bleeders but SSM and platelet counts are unreliable to predict VNT in pediatric EHPVO. Surveillance endoscopies may be needed in all pediatric EHPVO until better screening strategies are available. TRIAL REGISTRATION: Not applicable.

Metachronous Gastric Cancer Following Curative Endoscopic Resection of Early Gastric Cancer.

This review article summarizes knowledge about metachronous gastric cancer (MGC) occurring after curative endoscopic resection (ER) of early gastric cancer (EGC), treatment outcomes of patients who developed MGC, and efficacy of Helicobacter pylori eradication to prevent MGC. The incidence of MGC following curative ER increases over time and is higher than in patients undergoing gastrectomy. Increasing age and multifocal EGC are independent risk factors for developing MGC. An MGC following curative ER is usually a small (<20 mm) and differentiated intramucosal cancer. Most MGC lesions are found at an early stage on semiannual or annual surveillance endoscopy and are successfully treated by further ER, with excellent long-term outcomes. Eradication of H. pylori may reduce the risk of MGC following ER of EGC, but further prospective studies with long-term outcomes are required. Surveillance endoscopy following gastric ER should be continued indefinitely, due to the risk of MGC even after successful H. pylori eradication. Risk stratification and tailored endoscopic surveillance schedules need to be developed.

The potential for medical therapy to reduce the risk of colorectal cancer and optimize surveillance in inflammatory bowel disease.

It has been proposed that effective disease control through abrogation of inflammation in IBD may also reduce CRC risk in these individual patients. This article summarizes the potential for medical therapy to reduce the risk of CRC via primary and secondary prevention, and offers practical ways in which a goal of mucosal improvement or healing may be incorporated into clinical practice.

Hereditary diffuse gastric cancer - pathophysiology and clinical management.

Hereditary Diffuse Gastric Cancer is an autosomal dominant inherited gastric cancer syndrome caused by germline alterations in CDH1 (E-cadherin) and CTNNA1 (alpha-E-catenin) genes. Germline CDH1 alterations encompass small frameshifts, splice-site, nonsense, and missense mutations, as well as large rearrangements. Most CDH1 truncating mutations are pathogenic, and several missense CDH1 mutations have a deleterious effect on E-cadherin function. CDH1 testing should be performed in probands. Screening of at-risk individuals is indicated from the age of consent following counselling with a multidisciplinary team. In mutation-positive individuals prophylactic gastrectomy is recommended. Endoscopic surveillance is an option for those refusing/postponing gastrectomy, those with mutations of undetermined significance, and in CDH1-negative families. Ongoing research focus on the search of genetic causes other than CDH1 or CTNNA1 germline defects; assessment of the pathogenicity and penetrance of CDH1 missense mutations and identification of somatic mechanisms behind the progression from early (indolent) lesions to invasive (lethal) carcinomas.