ABSTRACT
BACKGROUND AND STUDY AIMS: Our aim was to determine the impact of the SARS-CoV-2 pandemic on the diagnosis and prognosis of colorectal cancer (CRC). PATIENTS AND METHODS: This prospective cohort study included individuals diagnosed with CRC between March 13, 2019 and June 20, 2021 across 21 Spanish hospitals. Two time periods were compared: prepandemic (from March 13, 2019 to March 13, 2020) and pandemic (from March 14, 2020 to June 20, 2021, lockdown period and 1 year after lockdown). RESULTS: We observed a 46.9% decrease in the number of CRC diagnoses (95% confidence interval (CI): 45.1%-48.7%) during the lockdown and 29.7% decrease (95% CI: 28.1%-31.4%) in the year after the lockdown. The proportion of patients diagnosed at stage I significantly decreased during the pandemic (21.7% vs. 19.0%; p = 0.025). Centers that applied universal preprocedure SARS-CoV-2 PCR testing experienced a higher reduction in the number of colonoscopies performed during the pandemic post-lockdown (34.0% reduction; 95% CI: 33.6%-34.4% vs. 13.7; 95% CI: 13.4%-13.9%) and in the number of CRCs diagnosed (34.1% reduction; 95% CI: 31.4%-36.8% vs. 26.7%; 95% CI: 24.6%-28.8%). Curative treatment was received by 87.5% of patients diagnosed with rectal cancer prepandemic and 80.7% of patients during the pandemic post-lockdown period (p = 0.002). CONCLUSIONS: The COVID-19 pandemic has led to a decrease in the number of diagnosed CRC cases and in the proportion of stage I CRC. The reduction in the number of colonoscopies and CRC diagnoses was higher in centers that applied universal SARS-CoV-2 PCR screening before colonoscopy. In addition, the COVID-19 pandemic has affected curative treatment of rectal cancers.
Subject(s)
COVID-19 , Colorectal Neoplasms , Rectal Neoplasms , Humans , SARS-CoV-2 , COVID-19/epidemiology , COVID-19/prevention & control , Pandemics , Prospective Studies , Communicable Disease Control , Prognosis , Colorectal Neoplasms/diagnosis , Colorectal Neoplasms/epidemiology , Retrospective Studies , COVID-19 TestingABSTRACT
BACKGROUND & AIMS: Among the characteristics of high-risk adenomas (HRAs), some may predict a higher risk of metachronous advanced lesions. Our aim was to assess which HRA characteristics are associated with high risk of metachronous colorectal cancer (CRC) or advanced adenomas (AAs). METHODS: We systematically searched Pubmed, EMBASE, and Cochrane for cohort studies and clinical trials of CRC or AA incidence at surveillance stratified by baseline lesion size, histology, and multiplicity. We calculated pooled relative risks (RRs) using a random-effects model. Heterogeneity was assessed with the I2 statistic. RESULTS: Fifty-five studies were included, with 936,540 patients with mean follow-up 5.4 ± 2.9 years. CRC incidence per 1000 person-years was 2.6 (2.1-3.0) for adenomas ≥20 mm, 2.7 (2.2-3.2) for high-grade dysplasia (HGD), 2.0 (1.8-2.3) for villous component, 0.8 (0.1-1.4) for ≥5 adenomas, 1.0 (0.7-1.2) for ≥3 adenomas. Metachronous CRC risk was higher in adenomas ≥20 mm vs 10 to 19 mm (RR, 2.08; 95% confidence interval [CI], 1.20-3.61), HGD vs low-grade dysplasia (RR, 2.89; 95% CI, 1.88-4.44), villous vs tubular (RR, 1.75; 95% CI, 1.33-2.31). No significant differences in CRC risk were found in ≥3 adenomas vs 1 to 2 (RR, 1.24; 95% CI, 0.84-1.83), nor in ≥5 adenomas vs 3 to 4 (RR, 0.79; 95% CI, 0.30-2.11). Compared with normal colonoscopy, RR for CRC risk was 2.61 (95% CI, 2.06-3.32) for ≥10mm, 6.62 (95% CI, 4.60-9.52) for HGD, 3.58 (95% CI, 2.24-5.73) for villous component, and 2.03 (95% CI, 1.40-2.94) for ≥3 adenomas. Similar trends were seen for metachronous AAs. CONCLUSION: Metachronous CRC risk is highest in patients with baseline adenomas with ≥20 mm or HGD. Multiplicity does not seem to be associated with substantially higher CRC risk in the near term.
Subject(s)
Adenoma , Colonic Polyps , Colorectal Neoplasms , Neoplasms, Second Primary , Humans , Adenoma/pathology , Cohort Studies , Colonic Polyps/pathology , Colonoscopy/adverse effects , Colorectal Neoplasms/epidemiology , Neoplasms, Second Primary/epidemiology , Risk FactorsABSTRACT
Introduction: deep sedation controlled by the endoscopist is safe in patients with low anesthetic risk (ASA I-II). However, scarce evidence is available in patients with intermediate risk (ASA III).Objective: to evaluate the safety of deep sedation with propofol controlled by the usual endoscopy staff (endoscopist, nurse, assistant) in outpatients classified as ASA III and the risk factors for the occurrence of complications during deep sedation.Patients and methods: this observational and single-center cross-sectional study included consecutive patients undergoing non-complex procedures in which deep sedation was administered by the endoscopy staff. Patients were divided into group I (ASA = III) and group II (ASA < III).Results: a total of 562 patients were included and 80 (14.2 %) were in group I. Complications related to deep sedation were more frequent in group I (23.8 % vs 14.5 %; p = 0.036), mainly mild desaturations (13.8 % vs 7.5 %; p = 0.058). Emergency intervention or death were not registered. The adjusted analysis identified age as the only independent baseline risk factor for developing global adverse events.Conclusion: ASA III patients developed more sedation-related complications than ASA I-II patients. However, these complications were mild and did not prevent the correct performance of the procedure. (AU)
Subject(s)
Humans , Conscious Sedation/adverse effects , Deep Sedation/adverse effects , Deep Sedation/methods , Endoscopy, Gastrointestinal , Propofol/adverse effects , Cross-Sectional Studies , Hypnotics and Sedatives/adverse effects , Prospective StudiesABSTRACT
BACKGROUND AND AIMS: Even after two years of pandemic, there are still uncertainties on how to proceed when we schedule endoscopic procedures. During the COVID-19 pandemic, some scientific societies recommended universal preprocedural testing for all patients. However, other societies recommended against and considered enough to maintain strict infection control strategies. Our aim was to evaluate this approach in order to see if it was safe for both patients and healthcare workers to proceed with the endoscopies without performing a systematic PCR on all patients. METHODS: Retrospective chart review of all patients undergoing endoscopy without preprocedural COVID testing at our center from March 2020 to May 2021. PCR tests performed in the patients receiving an endoscopic procedure were analyzed, and patients who tested positive between 14 days before and after the endoscopic procedure were selected. The registry of the endoscopy unit members participating in these procedures was also analyzed. RESULTS: A total of 10,132 procedures were performed in the unit with 26 patients infected with SARS-CoV-2. Nineteen of these procedures were performed in patients with unknown SARS-CoV-2 carrier status. In 23 (88.5%) cases, transmission occurred through social or familial contact, and in 3 (11.5%), transmission occurred in the hospital. Four health care workers became infected during this period and none of them were related to the endoscopic procedures performed in patients with COVID-19. CONCLUSIONS: SARS-CoV-2 positive testing in asymptomatic ambulatory patients is rare and the adequate use of individual protective measures emerges as the main way to control the spread of COVID-19 infection in endoscopy centers.
ABSTRACT
INTRODUCTION: deep sedation controlled by the endoscopist is safe in patients with low anesthetic risk (ASA I-II). However, scarce evidence is available in patients with intermediate risk (ASA III). OBJECTIVE: to evaluate the safety of deep sedation with propofol controlled by the usual endoscopy staff (endoscopist, nurse, assistant) in outpatients classified as ASA III and the risk factors for the occurrence of complications during deep sedation. PATIENTS AND METHODS: this observational and single-center cross-sectional study included consecutive patients undergoing non-complex procedures in which deep sedation was administered by the endoscopy staff. Patients were divided into group I (ASA = III) and group II (ASA < III). RESULTS: a total of 562 patients were included and 80 (14.2 %) were in group I. Complications related to deep sedation were more frequent in group I (23.8 % vs 14.5 %; p = 0.036), mainly mild desaturations (13.8 % vs 7.5 %; p = 0.058). Emergency intervention or death were not registered. The adjusted analysis identified age as the only independent baseline risk factor for developing global adverse events. CONCLUSION: ASA III patients developed more sedation-related complications than ASA I-II patients. However, these complications were mild and did not prevent the correct performance of the procedure.
Subject(s)
Deep Sedation , Propofol , Conscious Sedation/adverse effects , Cross-Sectional Studies , Deep Sedation/adverse effects , Deep Sedation/methods , Endoscopy, Gastrointestinal , Humans , Hypnotics and Sedatives/adverse effects , Propofol/adverse effects , Prospective StudiesABSTRACT
BACKGROUND: Patients with multiple or large adenomas are considered to be high-risk for metachronous colorectal cancer. OBJECTIVE: Evaluate the risks of detecting colorectal cancer, advanced adenoma, and advanced serrated polyps at 1-year surveillance colonoscopy in patients with >5 adenomas or adenomas >20 mm. DESIGN: Descriptive, retrospective, multicentric, cohort study. We calculated the absolute risk of developing colorectal cancer, advanced adenomas, and advanced serrated polyps at the 1-year surveillance colonoscopy. Potential risk factors for advanced neoplasia at follow-up were evaluated with univariable and multivariable logistic regression analyses. SETTINGS: This study included data from a multicenter cohort colorectal cancer screening program, conducted from January 2014 to December 2015, based on fecal immunochemical tests in Spain. PATIENTS: We included 2119 participants with at least 1 adenoma ≥20 mm or ≥5 adenomas of any size. MAIN OUTCOME MEASURES: We calculated the absolute risk of developing colorectal cancer, advanced adenomas, and advanced serrated polyps at the 1-year surveillance colonoscopy. Potential risk factors for advanced neoplasia at follow-up were evaluated with univariable and multivariable logistic regression analyses. RESULTS: At 1 year, participants displayed 6 colorectal cancers (0.3%), 228 advanced adenomas (10.5%), and 58 advanced serrated polyps (2.7%). The adjusted analysis identified 2 factors associated with advanced neoplasia: >5 adenomas (odds ratio 1.53; 95% CI: 1.15-2.03; p = 0.004) and polyps in a proximal location (OR 1.52; 95% CI: 1.15-2.02; p = 0.004). LIMITATIONS: First, the sample size was relatively small compared to other studies with similar aims. Another limitation was the lack of a comparison group, which could have provided more practical results in terms of surveillance recommendations. CONCLUSIONS: The colorectal cancer detection rate at a 1-year colonoscopy surveillance was low among patients classified at high risk of advanced neoplasia. The risk factors for advanced neoplasia were ≥5 adenomas and proximal polyps at baseline. See Video Abstract at http://links.lww.com/DCR/B820 . RIESGO DE CNCER COLORRECTAL Y DE PLIPOS AVANZADOS UN AO DESPUS DE LA RESECCIN DE ADENOMAS DE ALTO RIESGO: ANTECEDENTES:Los pacientes con adenomas múltiples o grandes se consideran de alto riesgo para desarrollar cáncer colorrectal metacrónico.OBJETIVO:Evaluar los riesgos de detectar cáncer colorrectal, adenoma avanzado y pólipos serrados avanzados en la colonoscopia de seguimiento al año, en pacientes con un número mayor o igual a 5 adenomas o adenomas de 20 mm o más.DISEÑO:Estudio descriptivo, retrospectivo, multicéntrico, de cohortes. Calculamos el riesgo absoluto de desarrollar cáncer colorrectal, adenomas avanzados y pólipos serrados avanzados en la colonoscopia de vigilancia al año. Los factores de riesgo potenciales para el desarrollo de una neoplasia avanzada en el seguimiento, fueron evaluados mediante un análisis de regresión logística univariable y multivariable.AJUSTES:Este estudio incluyó datos de un programa de cribado de cáncer colorrectal de cohorte multicéntrico, realizado entre enero de 2014 y diciembre de 2015, con base en pruebas inmunoquímicas de materia fecal, en España.PACIENTES:Incluimos 2119 participantes con al menos un adenoma ≥20 mm o con cinco o más adenomas de cualquier tamaño.PRINCIPALES MEDIDAS DE RESULTADO:Calculamos el riesgo absoluto de desarrollar cáncer colorrectal, adenomas avanzados y pólipos serrados avanzados en la colonoscopia de vigilancia al año. Los potenciales factores de riesgo para desarrollar una neoplasia avanzada en el seguimiento, se evaluaron mediante un análisis de regresión logística univariable y multivariable.RESULTADOS:Al año se encontraron en los pacientes participantes, 6 cánceres colorrectales (0,3%), 228 adenomas avanzados (10,5%) y 58 pólipos serrados avanzados (2,7%). Mediante el análisis ajustado se identificaron dos factores asociados con el desarrollo de neoplasia avanzada: un número igual o mayor a 5 adenomas (razón de probabilidades 1,53; IC del 95%: 1,15-2,03; p = 0,004) y la presencia de pólipos en una ubicación proximal (razón de probabilidades 1,52; IC del 95%: 1,15-2,02; p = 0,004).LIMITACIONES:Primero, el tamaño de la muestra fue relativamente pequeño en comparación con otros estudios con objetivos similares. Otra limitación fue la falta de un grupo comparativo, que podría haber proporcionado resultados más prácticos, en términos de recomendaciones de vigilancia.CONCLUSIÓNES:La tasa de detección de cáncer colorrectal mediante una colonoscopia de vigilancia al año, fue baja entre los pacientes clasificados como de alto riesgo de neoplasia avanzada. Los factores de riesgo para desarrollar una neoplasia avanzada fueron; un número igual o mayor a 5 adenomas y la presencia de pólipos proximales en la colonoscopia inicial de base. Consulte Video Resumen en http://links.lww.com/DCR/B820 . ( Traducción-Eduardo Londoño-Schimmer ).
Subject(s)
Adenoma , Colonic Polyps , Colorectal Neoplasms , Adenoma/diagnosis , Adenoma/epidemiology , Adenoma/surgery , Cohort Studies , Colonic Polyps/diagnosis , Colonic Polyps/epidemiology , Colonic Polyps/surgery , Colorectal Neoplasms/diagnosis , Colorectal Neoplasms/epidemiology , Colorectal Neoplasms/surgery , Humans , Retrospective StudiesABSTRACT
BACKGROUND & AIMS: There is a lack of clinical studies to establish indications and methodology for tattooing, therefore technique and practice of tattooing is very variable. We aimed to establish a consensus on the indications and appropriate techniques for colonic tattoo through a modified Delphi process. METHODS: The baseline questionnaire was classified into 3 areas: where tattooing should not be used (1 domain, 6 questions), where tattooing should be used (4 domains, 20 questions), and how to perform tattooing (1 domain 20 questions). A total of 29 experts participated in the 3 rounds of the Delphi process. RESULTS: A total of 15 statements were approved. The statements that achieved the highest agreement were as follows: tattooing should always be used after endoscopic resection of a lesion with suspicion of submucosal invasion (agreement score, 4.59; degree of consensus, 97%). For a colorectal lesion that is left in situ but considered suitable for endoscopic resection, tattooing may be used if the lesion is considered difficult to detect at a subsequent endoscopy (agreement score, 4.62; degree of consensus, 100%). A tattoo should never be injected directly into or underneath a lesion that might be removed endoscopically at a later point in time (agreement score, 4.79; degree of consensus, 97%). Details of the tattoo injection should be stated clearly in the endoscopy report (agreement score, 4.76; degree of consensus, 100%). CONCLUSIONS: This expert consensus has developed different statements about where tattooing should not be used, when it should be used, and how that should be done.
Subject(s)
Tattooing , Colon , Endoscopy , HumansABSTRACT
BACKGROUND: Current guidelines regarding surveillance after screening colonoscopy assume adequate bowel preparation. However, follow-up intervals after suboptimal cleansing are highly heterogeneous. We aimed to determine the diagnostic yield of early repeat colonoscopy in patients with suboptimal bowel preparation in fecal immunochemical test (FIT)-based screening colonoscopy. METHODS: An observational study including patients who underwent colonoscopy with suboptimal bowel preparation after positive FIT screening and then repeat colonoscopy within 1 year. Suboptimal preparation was defined as a Boston Bowel Preparation Scale (BBPS) score of 1 in any segment. Patients with a BBPS score of 0 in any segment or incomplete examination were excluded. The adenoma detection rate (ADR), advanced ADR (AADR), and colorectal cancer rate were calculated for the index and repeat colonoscopies. RESULTS: Of the 2474 patients with FIT-positive colonoscopy at our center during this period, 314 (12.7â%) had suboptimal preparation. Of the 259 (82.5â%) patients who underwent repeat colonoscopy, suboptimal cleansing persisted in 22 (9â%). On repeat colonoscopy, the ADR was 38.7â% (95â%CI 32.6â% to 44.8â%) and the AADR was 14.9â% (95â%CI 10.5â% to 19.4â%). The per-adenoma miss rate was 27.7â% (95â%CI 24.0â% to 31.6â%), and the per-advanced adenoma miss rate was 17.6â% (95â%CI 13.3â% to 22.7â%). After repeat colonoscopy, the post-polypectomy surveillance recommendation changed from 10 to 3 years in 14.7â% of the patients with previous 10-year surveillance recommendation. CONCLUSIONS: Patients with suboptimal bowel preparation on FIT-positive colonoscopy present a high rate of advanced adenomas in repeat colonoscopy, with major changes in post-polypectomy surveillance recommendations.
Subject(s)
Adenoma , Colonic Neoplasms , Colorectal Neoplasms , Adenoma/diagnostic imaging , Colonoscopy , Colorectal Neoplasms/diagnostic imaging , Early Detection of Cancer , Humans , IntestinesSubject(s)
Embolization, Therapeutic , Hemostasis, Endoscopic , Endosonography , Gastrointestinal Hemorrhage/diagnostic imaging , Gastrointestinal Hemorrhage/etiology , Gastrointestinal Hemorrhage/therapy , Humans , Peptic Ulcer Hemorrhage/etiology , Peptic Ulcer Hemorrhage/therapy , Recurrence , UlcerABSTRACT
Percutaneous endoscopic gastrostomy (PEG) is the method of choice for feeding and nutritional support in patients with a normal gastrointestinal function who require long-term enteral nutrition. We report our experience regarding an alternative endoscopic ultrasound (EUS)-guided PEG technique. A retrospective clinical experience case series study was conducted from January 2019 to November 2019 at a tertiary center. Adult patients deemed unfit for conventional PEG due to absence of transillumination or previous gastric surgery were enrolled. An EUS target was created by filling a glove with saline and placing it in the abdomen. EUS was performed and the target identified from the stomach. The abdominal wall was punctured from the stomach and a guidewire was advanced. The guidewire was knotted to a string, which was passed into the stomach and drawn back through the mouth. The procedure was continued following the traditional technique. Four patients underwent EUS-PEG in our center during the study period. Mean age was 65 years and 50% were male. Two patients (50%) had a body mass index over 30. PEG indications were tongue malignancies (50%), cerebrovascular disease (25%) and dementia (25%). One patient had a Roux-en-Y gastric bypass and percutaneous endoscopic jejunostomy was performed. Technical success rate was 100% and no complications occurred. This case series shows that the EUS-guided PEG technique is a safe alternative in patients deemed unfit for conventional PEG.
Subject(s)
Gastrostomy , Jejunostomy , Ultrasonography, Interventional , Adult , Aged , Enteral Nutrition , Female , Gastrostomy/methods , Humans , Male , Retrospective StudiesABSTRACT
OBJETIVO: Desarrollar un modelo de sepsis abdominal en animal de experimentación. MATERIAL Y MÉTODOS: Se utilizan ratas Sprague-Dawley(R), machos de 5 semanas con pesos entre 270-280 g en el momento de la inoculación (N=39). Inicialmente se realiza un estudio piloto (N=9), distribuyéndolas en 3 grupos (3/3/3) con inóculo de 1cc de Escherichia coli ATCC 25922 intraperitoneal en concentraciones de 10E8, 10E9 y 10E10 UFC. En un segundo estudio (N=6) con distribución en dos grupos (3/3) se utilizan 1cc una concentración de E. coli 10E10 UFC que se diluyen en 10 y 15 ml de agua destilada para su inoculación. Por último se inicia un ensayo experimental con aleatorización de 24 ratas en tres grupos de tratamiento tras la infección intraperitoneal: Grupo I con suero fisiológico (N=6), Grupo II con antibiótico (ceftriaxona) (N=9), Grupo III con antibiótico más adyuvante (ceftriaxona más alicina) (N=9). Se realizan muestras microbiológicas de sangre y líquido peritoneal, así como estudio histopatológico de órganos intraperitoneales (hígado, diafragma y peritoneo). RESULTADOS: Se observa muerte en el 100% de las ratas infectadas con la concentración de E. coli 10E10 UFC con la dilución de 15 ml de agua destilada y sin antibiótico. El hemocultivo y cultivo de líquido peritoneal es positivo a la misma cepa en todas ellas. Se observa la formación de abscesos en la superficie del hígado e infiltración por polimorfonucleares en los tejidos. CONCLUSIÓN: Se establece que la dosis letal de E. coli es 10E10 UFC diluida en 15 ml agua destilada en inyección intraperitoneal
OBJECTIVE: The aim of the study was to develop a model of abdominal sepsis in the experimental animal. MATERIAL AND METHODS: Sprague-Dawley male rats of 5 weeks (N=39) were used. Initially, a pilot study (N = 9) was performed and distributed in 3 groups with 1cc inoculum of Escherichia coli ATCC 25922 intraperitoneally at concentrations of 10E8, 10E9 and 10E10 CFU. Subsequently, concentrations of 10E10 CFU are used in two groups of 3 rats with dilutions of 10 cc and 15 cc of distilled water respectively. Finally, a randomized trial of 24 rats was started in three treatment groups after intraperitoneal infection: Group I with physiological serum (N = 6), Group II with ceftriaxone (N = 9), Group III with ceftriaxone plus allicin (N = 9). Microbiological samples of blood and peritoneal fluid were made, as well as histopathological study of intraperitoneal organs (liver, diaphragm and peritoneum). RESULTS: Death of 100% of the rats infected with 10E10 E. coli UFC concentration with the dilution of 15 ml of distilled water and without antibiotic was oberved. The blood culture and peritoneal fluid culture was positive for the same strain in all of them. The formation of abscesses on the liver surface and polymorphonuclear infiltration in tissues were observed. CONCLUSION: The lethal dose of E. coli is 10E10 CFU diluted in 15 cc distilled water by intraperitoneal injection
Subject(s)
Animals , Male , Rats , Bacterial Load , Disease Models, Animal , Escherichia coli Infections/microbiology , Peritonitis/microbiology , Anti-Bacterial Agents/therapeutic use , Escherichia coli Infections/drug therapy , Escherichia coli Infections/pathology , Liver Abscess/microbiology , Liver Abscess/pathology , Peritonitis/drug therapy , Peritonitis/pathology , Pilot Projects , Random Allocation , Rats, Sprague-DawleyABSTRACT
BACKGROUND & AIMS: Guidelines recommend that individuals with familial colorectal cancer undergo colonoscopy surveillance instead of average-risk screening. However, these recommendations vary widely. To substantiate appropriate surveillance strategies, precise and valid evidence-based risk estimates are needed for individuals with a family history of colorectal cancer (CRC). METHODS: We systematically searched MEDLINE, EMBASE, and Cochrane from inception to July 2018 for case-control and cohort studies investigating the effect of family history on CRC risk. We calculated summary estimates of pooled relative risks (RRs) using a random-effects model. Life tables were created to convert RR estimates into absolute risk estimates. RESULTS: We screened 4417 articles and identified 42 eligible case-control and 20 cohort studies. In case-control studies, the RR for CRC in patients with 1 first-degree relative (FDR with CRC) was 1.92 (95% CI, 1.53-2.41) and 1.37 (95% CI, 0.76-2.46) for cohort studies. For individuals with 2 or more FDRs with CRC, the RR was 2.81 in case-control studies (95% CI, 1.73-4.55) and 2.40 in cohort studies (95% CI, 1.76-3.28). For individuals having a FDR diagnosed with CRC at an age younger than 50 years, the RR for CRC in their FDRs was 3.57 in case-control studies (95% CI, 1.07-11.85) and 3.26 in cohort studies (95% CI, 2.82-3.77). The cumulative absolute risks for CRC at 85 years in Western Europe were 4.8% for persons with 1 FDR with CRC (95% CI, 2.7%-8.3%), 8.2% for individuals with 2 or more FDRs (95% CI, 6.1%-10.9%), and 11% for persons with a FDR diagnosed with CRC at an age younger than 50 years (95% CI, 9.5%-12.4%). CONCLUSIONS: In this systematic review and meta-analysis, we found that the RR of CRC among FDRs is lower than previously expected, especially based on cohort studies. Risk estimates are affected by the number of relatives with CRC and their age at diagnosis. Intensified colonoscopy surveillance strategies could be considered for high-risk groups. PROSPERO trial identification no: CRD42018103058.