American Society for Gastrointestinal Endoscopy guideline on the role of endoscopy in familial adenomatous polyposis syndromes
2020; Elsevier BV; Volume: 91; Issue: 5 Linguagem: Inglês
10.1016/j.gie.2020.01.028
ISSN1097-6779
AutoresJulie Yang, Suryakanth R. Gurudu, Cathryn Koptiuch, Deepak Agrawal, James Buxbaum, Syed M. Abbas Fehmi, Douglas S. Fishman, Mouen A. Khashab, Laith H. Jamil, Terry L. Jue, Joanna K. Law, Jeffrey K. Lee, Mariam Naveed, Bashar Qumseya, Mandeep S. Sawhney, Nirav Thosani, Sachin Wani, N. Jewel Samadder,
Tópico(s)Gastric Cancer Management and Outcomes
ResumoFamilial adenomatous polyposis (FAP) syndrome is a complex entity, which includes FAP, attenuated FAP, and MUTYH-associated polyposis. These patients are at significant risk for colorectal cancer and carry additional risks for extracolonic malignancies. In this guideline, we reviewed the most recent literature to formulate recommendations on the role of endoscopy in this patient population. Relevant clinical questions were how to identify high-risk individuals warranting genetic testing, when to start screening examinations, what are appropriate surveillance intervals, how to identify endoscopically high-risk features, and what is the role of chemoprevention. A systematic literature search from 2005 to 2018 was performed, in addition to the inclusion of seminal historical studies. Most studies were from worldwide registries, which have compiled years of data regarding the natural history and cancer risks in this cohort. Given that most studies were retrospective, recommendations were based on epidemiologic data and expert opinion. Management of colorectal polyps in FAP has not changed much in recent years, as colectomy in FAP is the standard of care. What is new, however, is the developing body of literature on the role of endoscopy in managing upper GI and small-bowel polyposis, as patients are living longer and improved endoscopic technologies have emerged. Familial adenomatous polyposis (FAP) syndrome is a complex entity, which includes FAP, attenuated FAP, and MUTYH-associated polyposis. These patients are at significant risk for colorectal cancer and carry additional risks for extracolonic malignancies. In this guideline, we reviewed the most recent literature to formulate recommendations on the role of endoscopy in this patient population. Relevant clinical questions were how to identify high-risk individuals warranting genetic testing, when to start screening examinations, what are appropriate surveillance intervals, how to identify endoscopically high-risk features, and what is the role of chemoprevention. A systematic literature search from 2005 to 2018 was performed, in addition to the inclusion of seminal historical studies. Most studies were from worldwide registries, which have compiled years of data regarding the natural history and cancer risks in this cohort. Given that most studies were retrospective, recommendations were based on epidemiologic data and expert opinion. Management of colorectal polyps in FAP has not changed much in recent years, as colectomy in FAP is the standard of care. What is new, however, is the developing body of literature on the role of endoscopy in managing upper GI and small-bowel polyposis, as patients are living longer and improved endoscopic technologies have emerged. Colorectal cancer (CRC) is the third most common cancer and the second leading cause of death in both men and women in the United States.1Siegel R.L. Miller K.D. Jemal A. Cancer statistics, 2015.CA Cancer J Clin. 2015; 65: 5-29Crossref PubMed Scopus (9825) Google Scholar Hereditary CRC because of mutations and defects in certain genes comprises roughly 5% of all CRC. Familial adenomatous polyposis (FAP) is a classic example of hereditary CRC, accounting for 1% to 2% of all CRCs. The risk of CRC is nearly 100% in classic FAP and nearly 70% in attenuated forms of FAP (AFAP), in addition to an increased risk for extraintestinal malignancies.2Kanth P. Grimmett J. Champine M. et al.Hereditary colorectal polyposis and cancer syndromes: a primer on diagnosis and management.Am J Gastroenterol. 2017; 112: 1509-1525Crossref PubMed Scopus (22) Google Scholar MUTYH-associated polyposis (MAP) is a related autosomal recessive condition with slightly lower risks of CRC and upper GI cancers. Given the substantial cancer risk, patients with these conditions are advised to receive intensive endoscopic surveillance and/or prophylactic surgery as part of their clinical management. The role of genetic counseling also becomes important in managing these patients and their family members. The aim of this document is to provide evidence-based recommendations and clinical guidance in regard to the management of hereditary colorectal polyposis syndromes including FAP, AFAP, and MAP. We highlight the evidence supporting the use of endoscopy and potential chemoprevention strategies for the reduction of CRC and associated extracolonic malignancies. An insight into the best use of genetic counseling is discussed to provide busy clinicians tools to optimally manage this high-risk population. This document was prepared by a working group of the Standards of Practice committee of the American Society for Gastrointestinal Endoscopy (ASGE). It includes a systematic review of available literature along with guidelines for the role of endoscopy in the management of FAP syndromes. After evidence synthesis, recommendations were drafted by the full panel during a face-to-face meeting on March 18, 2018 and approved by the Standards of Practice committee members and the ASGE Governing Board. The panel was composed of 2 principal authors (J.Y., S.R.G.), a content expert (N.J.S.), a genetic counselor (C.K.), the committee chair (S.B.W.), and the members of the Standards of Practice committee. All panel members disclosed possible intellectual and financial conflicts of interest in concordance with ASGE policies (https://www.asge.org/docs/default-source/about-asge/mission-and-governance/asge-conflict-of-interest-and-disclosure-policy.pdf). For all clinical topics, potentially relevant patient-important outcomes were identified a priori and rated from “not important” to “critical” through a consensus process. Relevant clinical topics were to identify high-risk individuals warranting genetic testing, when to start screening examinations, appropriate surveillance intervals, endoscopic identification of high-risk features and role of chemoprevention. A systematic review of the literature was performed through the databases PubMed, EMBASE, Scopus, and Cochrane from January 2005 to May 2018 based on an update of the literature from the most recent European guideline addressing FAP.3Vasen H.F.A. Moslein G. Alonso A. et al.Guidelines for the clinical management of familial adenomatous polyposis.Gut. 2008; 57: 704-713Crossref PubMed Scopus (425) Google Scholar A medical librarian (L.M.) conducted a comprehensive search using the following terms that were developed by the principal authors and content experts (J.Y., S.R.G., N.J.S.): familial adenomatous polyposis, adenomatous polyposis coli, colonoscopy, sigmoidoscopy, endoscopy, enteroscopy, capsule endoscopy, diagnosis, and therapy. Inclusion criteria were articles in the English language with the exclusion of animal studies, reviews, letters, editorials, and comments. Given the rarity of the disease, case reports were included. Seminal papers before 2005 were also included. Details of the search strategy are reported in Appendix 1 (available online at www.giejournal.org). Citations were imported into EndNote (Thompson Reuters, Philadelphia, Pa, USA), and duplicates were removed. The EndNote library was then uploaded into Covidence (www.covidence.org). The eligibility of each study was reviewed by 2 independent authors with resolution of any conflicts from the third author. One hundred seventy-two studies were identified. Most studies lacked a prospective design, and randomized controlled trials were limited to the use of chemoprevention, with none found in the endoscopic management of these conditions. The overall quality of evidence was low. The certainty in the body of evidence (also known as quality of the evidence or confidence in the estimated effects) was assessed for each effect estimate of the outcomes of interest on the following domains: risk of bias, precision, consistency and magnitude of the estimates of effects, directness of the evidence, risk of publication bias, presence of dose–effect relationship, and an assessment of the effect of residual, opposing confounders. During an in-person meeting, the panel developed recommendations based on certainty in the evidence, balance of benefits and harms of the compared management options, assumptions about the values and preferences associated with the decision along with available data on resource utilization, and cost-effectiveness. The final wording of the recommendations (including direction and strength), remarks, and qualifications were decided by consensus using criteria highlighted in Table 14Guyatt G. Oxman A.D. Akl E.A. et al.GRADE guidelines: 1. Introduction—GRADE evidence profiles and summary of findings tables.J Clin Epidemiol. 2011; 64: 383-394Abstract Full Text Full Text PDF PubMed Scopus (2588) Google Scholar and were approved by all members of the panel. The strength of individual recommendations is based on the aggregate evidence quality and an assessment of the anticipated benefits and harms. Weaker recommendations are indicated by phrases such as “we suggest…”, whereas stronger recommendations are typically stated as “we recommend…”.Table 1System for rating the quality of evidence for guidelinesQuality of evidenceDefinitionSymbolHigh qualityWe are very confident that the true effect lies close to that of the estimate of effect.⊕ ⊕ ⊕ ⊕Moderate qualityWe are moderately confident in the effect estimate: The true effect is likely to be close to the estimate of effect, but there is a possibility that it is substantially different.⊕ ⊕ ⊕ ○Low qualityOur confidence in the effect estimate is limited: The true effect may be substantially different from the estimate of effect.⊕ ⊕ ○ ○Very low qualityWe have very little confidence in the effect estimate: The true effect is likely to be substantially different from the estimate of effect.⊕ ○ ○ ○Adapted from Guyatt et al.4Guyatt G. Oxman A.D. Akl E.A. et al.GRADE guidelines: 1. Introduction—GRADE evidence profiles and summary of findings tables.J Clin Epidemiol. 2011; 64: 383-394Abstract Full Text Full Text PDF PubMed Scopus (2588) Google Scholar Open table in a new tab Adapted from Guyatt et al.4Guyatt G. Oxman A.D. Akl E.A. et al.GRADE guidelines: 1. Introduction—GRADE evidence profiles and summary of findings tables.J Clin Epidemiol. 2011; 64: 383-394Abstract Full Text Full Text PDF PubMed Scopus (2588) Google Scholar FAP is an autosomal dominant disease characterized by the development of hundreds of colorectal adenomatous polyps that progress to CRC in nearly 100% of persons if left untreated (Fig. 1A-D). FAP is very rare, with a global prevalence of 1 in 10,000 live births.5Jarvinen H.J. Epidemiology of familial adenomatous polyposis in Finland: impact of family screening on the colorectal cancer rate and survival.Gut. 1992; 33: 357-360Crossref PubMed Google Scholar, 6Bisgaard M.L. Fenger K. Bülow S. et al.Familial adenomatous polyposis (FAP): frequency, penetrance, and mutation rate.Hum Mutat. 1994; 3: 121-125Crossref PubMed Google Scholar, 7Bülow S. Faurschou Nielsen T. et al.The incidence rate of familial adenomatous polyposis. Results from the Danish Polyposis Register.Int J Colorectal Dis. 1996; 11: 88-91Crossref PubMed Google Scholar FAP is the second most common hereditary monogenic CRC syndrome and accounts for approximately 1% of all CRCs. FAP classically presents in early adolescence with rectal bleeding or other nonspecific GI symptoms, and without intervention nearly 100% will develop CRC. In addition, there is a lower risk for extracolonic cancers including that of stomach, duodenum, thyroid, hepatoblastoma, osteomas, pancreas, and desmoid tumors (Table 2).8Jasperson K.W. Tuohy T.M. Neklason D.W. et al.Hereditary and familial colon cancer.Gastroenterology. 2010; 138: 2044-2058Abstract Full Text Full Text PDF PubMed Scopus (551) Google ScholarTable 2Cancer risks and genes associated with hereditary polyposis syndromesSyndromeGeneInheritance patternLifetime cancer risksPercentageFamilial adenomatous polyposisAPCAutosomal dominantColorectumDuodenum/ampullaStomachPancreasThyroidLiver (hepatoblastoma)Central nervous system (medulloblastoma)Nearly 1004-12121-21-2<1Attenuated FAPAPCAutosomal dominantColorectumDuodenum/ampullaThyroid704-121-2MUTYH-associated polyposisMUTYHAutosomal recessiveColorectumDuodenumStomach8041 Open table in a new tab AFAP is a less severe form of the disease. It is characterized by later onset of adenomas, fewer adenomas (0-100 colon adenomatous polyps with an average of 30), a lower lifetime risk of CRC (70%), and a predilection for proximal colon polyps and cancer.9Burt R.W. Leppert M.F. Slattery M.L. et al.Genetic testing and phenotype in a large kindred with attenuated familial adenomatous polyposis.Gastroenterology. 2004; 127: 444-451Abstract Full Text Full Text PDF PubMed Scopus (114) Google Scholar, 10Knudsen A.L. Bülow S. Tomlinson I. et al.Attenuated familial adenomatous polyposis: results from an international collaborative study.Colorectal Dis. 2010; 12: 243-249Crossref PubMed Scopus (0) Google Scholar, 11Ibrahim A. Barnes D.R. Dunlop J. et al.Attenuated familial adenomatous polyposis manifests as autosomal dominant late-onset colorectal cancer.Eur J Hum Genet. 2014; 22: 1330-1333Crossref PubMed Scopus (0) Google Scholar Both FAP and AFAP are caused by germline mutations in the adenomatous polyposis coli (APC) gene, which encodes a tumor suppressor.8Jasperson K.W. Tuohy T.M. Neklason D.W. et al.Hereditary and familial colon cancer.Gastroenterology. 2010; 138: 2044-2058Abstract Full Text Full Text PDF PubMed Scopus (551) Google Scholar,12Giardiello F.M. Brensinger J.D. Petersen G.M. AGA technical review on hereditary colorectal cancer and genetic testing.Gastroenterology. 2001; 121: 198-213Abstract Full Text PDF PubMed Google Scholar Mutations throughout the gene are associated with FAP, with a predilection for AFAP when the mutation is located in the 5’ or 3’ region of the gene. Although patients usually have a family history of FAP, up to 30% of FAP and AFAP cases are because of new (“de novo”) germline mutations in the APC gene.6Bisgaard M.L. Fenger K. Bülow S. et al.Familial adenomatous polyposis (FAP): frequency, penetrance, and mutation rate.Hum Mutat. 1994; 3: 121-125Crossref PubMed Google Scholar,13Nielsen M. Hes F.J. Nagengast F.M. et al.Germline mutations in APC and MUTYH are responsible for the majority of families with attenuated familial adenomatous polyposis.Clin Genet. 2007; 71: 427-433Crossref PubMed Scopus (108) Google Scholar, 14Neklason D.W. Stevens J. Boucher K.M. et al.American founder mutation for attenuated familial adenomatous polyposis.Clin Gastroenterol Hepatol. 2008; 6: 46-52Abstract Full Text Full Text PDF PubMed Scopus (0) Google Scholar, 15Lynch H.T. Smyrk T. McGinn T. et al.Attenuated familial adenomatous polyposis (AFAP). A phenotypically and genotypically distinctive variant of FAP.Cancer. 1995; 76: 2427-2433Crossref PubMed Scopus (220) Google Scholar, 16Hernegger G.S. Moore H.G. Guillem J.G. Attenuated familial adenomatous polyposis: an evolving and poorly understood entity.Dis Colon Rectum. 2002; 45 (discussion 134-6): 127-134Crossref PubMed Scopus (120) Google Scholar, 17Aretz S. Uhlhaas S. Caspari R. et al.Frequency and parental origin of de novo APC mutations in familial adenomatous polyposis.Eur J Hum Genet. 2004; 12: 52-58Crossref PubMed Scopus (94) Google Scholar Therefore, family history may not always be present, and genetic testing is recommended to make a molecular confirmatory diagnosis of FAP before proceeding with morbid surgery or invasive endoscopic screening. Genetic testing is also recommended in the following circumstances: (1) when 10 or more cumulative adenomatous polyps are noted on a single colonoscopy, (2) if an individual has 10 or more adenomas and a personal history of CRC, or (3) if an individual has 20 or more adenomatous polyps in his or her lifetime.18Grover S. Kastrinos F. Steyerberg E.W. et al.Prevalence and phenotypes of APC and MUTYH mutations in patients with multiple colorectal adenomas.JAMA. 2012; 308: 485-492Crossref PubMed Scopus (99) Google Scholar Even after genetic testing, up to 30% of individuals with a clinical diagnosis of FAP will not have an identifiable pathogenic mutation in the APC gene. Numerous reasons for this observation are reviewed elsewhere.19Adam R. Spier I. Zhao B. et al.Exome sequencing identifies biallelic MSH3 germline mutations as a recessive subtype of colorectal adenomatous polyposis.Am J Hum Genet. 2016; 99: 337-351Abstract Full Text Full Text PDF PubMed Scopus (78) Google Scholar There are also several newly discovered genes with polyposis phenotypes similar to FAP and AFAP, including POLE, POLD1, and GREM1.20Bellido F. Pineda M. Aiza G. et al.POLE and POLD1 mutations in 529 kindred with familial colorectal cancer and/or polyposis: review of reported cases and recommendations for genetic testing and surveillance.Genet Med. 2016; 18: 325-332Abstract Full Text Full Text PDF PubMed Scopus (92) Google Scholar,21Esteban-Jurado C. Garre P. Vila M. et al.New genes emerging for colorectal cancer predisposition.World J Gastroenterol. 2014; 20: 1961-1971Crossref PubMed Scopus (26) Google Scholar Genetic counseling is recommended for all patients with or suspected to have an adenomatous polyposis syndrome.22Syngal S. Brand R.E. Church J.M. et al.ACG clinical guidelines: genetic testing and management of hereditary gastrointestinal cancer syndromes.Am J Gastroenterol. 2015; 110: 223-262Crossref PubMed Google Scholar Patients with hereditary adenomatous polyposis desire to receive care from healthcare providers who understand their condition and can provide guidance and support for this complex disease.23Fritzell K. Persson C. Björk J. et al.Patients’ views of surgery and surveillance for familial adenomatous polyposis.Cancer Nurs. 2010; 33: 17-23Crossref PubMed Scopus (0) Google Scholar Genetic counselors play a key role in the patient’s diagnosis as well as clinical care for patients’ ongoing needs. This includes education regarding the implications for both affected individuals and their family members, inheritance of the condition, and the meaning of their genetic test results. At-risk family members are identified for testing, family communication is facilitated, and multidisciplinary care is coordinated for screening patients and children based on polyposis phenotype and the parents’ decision. Patients and their children are also assessed for psychological support.24Gjone H. Diseth T.H. Fausa O. et al.Familial adenomatous polyposis: mental health, psychosocial functioning and reactions to genetic risk in adolescents.Clin Genet. 2011; 79: 35-43Crossref PubMed Scopus (10) Google Scholar Because patients are often tested in adolescence and childhood, their needs for resources change as they approach various life stages, especially during college and family planning. Continued involvement of genetic counselors in the care of polyposis patients creates an opportunity to share up-to-date information regarding cancer risks, current recommendations, improvements in genetic testing technology (for those without previously detectable mutations), affordability, screening modalities, reproductive services, and research opportunities. If a facility does not have its own genetic counselor, providers can search www.NSGC.org (National Society of Genetic Counselors) or www.ABGC.net (American Board of Genetic Counseling) to find an available counselor in the area. The primary goal of screening and surveillance endoscopy in FAP patients is early detection of cancer, prevention of cancer through polypectomy, and thereby reduction in cancer incidence and mortality. The risk of CRC is nearly 100% in FAP patients who do not undergo endoscopic or surgical treatment. Although there are no randomized or prospective studies regarding different screening strategies, multiple observational studies and a systematic review have demonstrated a reduction in CRC incidence and mortality in patients participating in screening programs.5Jarvinen H.J. Epidemiology of familial adenomatous polyposis in Finland: impact of family screening on the colorectal cancer rate and survival.Gut. 1992; 33: 357-360Crossref PubMed Google Scholar,25Barrow P. Khan M. Lalloo F. et al.Systematic review of the impact of registration and screening on colorectal cancer incidence and mortality in familial adenomatous polyposis and Lynch syndrome.Br J Surg. 2013; 100: 1719-1731Crossref PubMed Scopus (61) Google Scholar, 26Alm T. Surgical treatment of hereditary adenomatosis of the colon and rectum in Sweden.Acta Chir Scan. 1975; 141: 228-237PubMed Google Scholar, 27Bussey H.J. Familial polyposis coli. The Johns Hopkins University Press, Baltimore, MD1975Google Scholar, 28Bülow S. Clinical features in familial polyposis coli. Results of the Danish Polyposis Register.Dis Colon Rectum. 1986; 29: 102-107Crossref PubMed Google Scholar, 29Vasen H.F. Griffioen G. Offerhaus G.J. et al.The value of screening and central registration of families with FAP. A study of 82 families in Netherlands.Dis Colon Rectum. 1990; 33: 227-230Crossref PubMed Scopus (0) Google Scholar Barrow et al25Barrow P. Khan M. Lalloo F. et al.Systematic review of the impact of registration and screening on colorectal cancer incidence and mortality in familial adenomatous polyposis and Lynch syndrome.Br J Surg. 2013; 100: 1719-1731Crossref PubMed Scopus (61) Google Scholar reviewed results from 27 studies comparing CRC incidence between symptomatic and screened patients. All but 1 study showed a statistically significant reduction in CRC incidence in the screening population with an odds ratio of less than 1.00 in all studies. Eight studies compared CRC-related mortality between screened and symptomatic groups in FAP. All studies showed a significant reduction in CRC-related mortality with screening. Bülow et al30Bülow S. Bulow C. Nielsen T.F. et al.Centralized registration, prophylactic examinations, and treatment results in improved prognosis in FAP. Results of Danish Polyposis register.Scand J Gastroenterol. 1995; 30: 989-993Crossref PubMed Scopus (0) Google Scholar reported improved 10- year survival in patients with FAP who were participants of the centralized registration, prophylactic examination, and treatment. Several other registry studies have also shown an improved survival in patients who were undergoing surveillance colonoscopies or received prophylactic colectomy.31Bertario L. Presciuttini S. Sala P. et al.Causes of death and postsurgical survival in familial adenomatous polyposis: results from Italian Registry. Italian Registry of Familial Polyposis Writing Committee.Semin Surg Oncol. 1994; 10: 225-234Crossref PubMed Scopus (0) Google Scholar, 32Heiskanen I. Luostarinen T. Jarvinen H.J. Impact of screening examinations on survival in FAP.Scan J Gastroenterol. 2000; 35: 1284-1287Crossref PubMed Scopus (0) Google Scholar, 33Arvantis M.L. Jagelman D.G. Fazio V.W. et al.Mortality in patients with FAP.Dis Colon Rectum. 1990; 33: 639-642Crossref PubMed Scopus (0) Google Scholar, 34Mallinson E.K. Newton K.F. Bowen J. et al.The impact of screening and genetic registration on mortality and colorectal cancer incidence in FAP.Gut. 2010; 59: 1378-1382Crossref PubMed Scopus (0) Google Scholar, 35Bülow S. Results of national registration of familial adenomatous polyposis.Gut. 2003; 52: 742-746Crossref PubMed Scopus (156) Google Scholar, 36Gibsons D.C. Sinha A. Phillips R.K. et al.Colorectal cancer: no longer the issue in familial adenomatous polyposis?.Fam Cancer. 2011; 10: 11-20Crossref PubMed Scopus (25) Google Scholar Based on data from multiple registries, experts recommend APC gene testing and screening examinations in children at ages 10 to 12 years because CRC development is rare before this age.3Vasen H.F.A. Moslein G. Alonso A. et al.Guidelines for the clinical management of familial adenomatous polyposis.Gut. 2008; 57: 704-713Crossref PubMed Scopus (425) Google Scholar Younger children (6 months to 5 years) can undergo confirmatory APC genetic testing if parents are agreeable to screen for hepatoblastoma with α-fetoprotein and liver US every 6 months. Otherwise, testing is deferred until ages 10 to 12 years. Children who do not carry an APC gene mutation are recommended to follow average-risk screening guidelines. Combined data from European registries of FAP revealed no CRC before age 10 years, .2% developed cancer before age 15 years, and 1.3% developed cancer before age 20 years.3Vasen H.F.A. Moslein G. Alonso A. et al.Guidelines for the clinical management of familial adenomatous polyposis.Gut. 2008; 57: 704-713Crossref PubMed Scopus (425) Google Scholar A survey by Church et al37Church J.M. McGannon E. Burke C. et al.Teenagers with familial adenomatous polyposis: What is their risk for colorectal cancer?.Dis Colon Rectum. 2002; 45: 887-889Crossref PubMed Scopus (0) Google Scholar included data from 26 registries and found only 1 case of invasive cancer reported before age 17 years. In general, the risk of CRC in patients with FAP starts in the second decade and increases with age. Because the rectum is almost always involved in patients with classic FAP, sigmoidoscopy is adequate for screening purposes (Table 3).27Bussey H.J. Familial polyposis coli. The Johns Hopkins University Press, Baltimore, MD1975Google Scholar Patients who do not have polyps on initial sigmoidoscopy should be offered screening at 2-year intervals. Children found to harbor polyps in the rectosigmoid colon should undergo a complete colonoscopy to assess the severity of polyposis and to resect large polyps. It is also reasonable to initially screen children with colonoscopy, given the specific challenges with bowel preparation and need for sedation even when performing a sigmoidoscopy. Polyps in FAP follow the adenoma–carcinoma sequence and take approximately 15 to 20 years for the development of malignancy.27Bussey H.J. Familial polyposis coli. The Johns Hopkins University Press, Baltimore, MD1975Google Scholar In patients with FAP and a manageable polyp burden, surveillance colonoscopy has been shown to reduce the risk of CRC.5Jarvinen H.J. Epidemiology of familial adenomatous polyposis in Finland: impact of family screening on the colorectal cancer rate and survival.Gut. 1992; 33: 357-360Crossref PubMed Google Scholar,7Bülow S. Faurschou Nielsen T. et al.The incidence rate of familial adenomatous polyposis. Results from the Danish Polyposis Register.Int J Colorectal Dis. 1996; 11: 88-91Crossref PubMed Google Scholar,34Mallinson E.K. Newton K.F. Bowen J. et al.The impact of screening and genetic registration on mortality and colorectal cancer incidence in FAP.Gut. 2010; 59: 1378-1382Crossref PubMed Scopus (0) Google Scholar,38Ishikawa H. Mutoh M. Iwama T. et al.Endoscopic management of FAP in patients refusing colectomy.Endoscopy. 2016; 48: 51-55PubMed Google Scholar Once the polyp burden becomes difficult to manage endoscopically, surgical colectomy is recommended. In high-risk patients with a genetic mutation and no polyps on initial sigmoidoscopy or colonoscopy, a follow-up screening colonoscopy should be offered in late teenage years and continued every 2 years until 40 years of age.39Balmana J. Castells A. Cervantes A. Familial colorectal cancer risk: ESMO clinical practice guidelines.Ann Oncol. 2010; 21: 78-81Abstract Full Text Full Text PDF PubMed Scopus (33) Google Scholar,40Provenzale D. Gupta S. Ahnen D. et al.Genetic/familial high-risk assessment: colorectal version 1.2016. Clinical practice guidelines in oncology.J Natl Compr Cancer Netw. 2016; 14: 1010-1030Crossref PubMed Google Scholar If there are no adenomas, screening intervals can be gradually extended.Table 3Colorectal screening/surveillance recommendations in patients and family members at risk for FAP, attenuated FAP, and MUTYH polyposisConditionScreening examinationStarting age at screeningSurveillance intervalQuality of evidenceFAPSigmoidoscopy or colonoscopyColonoscopy when polyps are found10-12 y1-2 y⊕ ⊕ ⊕ ○Attenuated FAPColonoscopy18-20 y1-2 y⊕ ⊕ ○ ○MUTYH- associated polyposisColonoscopy18-20 y1-2 y⊕ ⊕ ○ ○MUTYH heterozygote + first-degree relative with CRCColonoscopy40 y, or before 10 y age of first-degree relative’s age of CRC diagnosis5 y⊕ ○ ○ ○MUTYH heterozygote without family history of CRCUnknownUnknownUnknown_After total colectomy with IPAAPouch endoscopy1 y after surgery1-2 y6 mo if advanced adenoma including HGD⊕ ○ ○ ○After subtotal colectomy and ileorectal anastomosisSigmoidoscopy6 mo after surgery6 mo to 1 y⊕ ○ ○ ○FAP, Familial adenomatous polyposis; CRC, colorectal cancer; IPAA, ileal pouch anal anastomosis; HGD, high-grade dysplasia. Open table in a new tab FAP, Familial adenomatous polyposis; CRC, colorectal cancer; IPAA, ileal pouch anal anastomosis; HGD, high-grade dysplasia. The use of chromoendoscopy in FAP has also been studied. In a small case series, chromoendoscopy detected a significantly higher number of colon polyps (43.3 ± 38.5) when compared with white-light endoscopy (12.2 ± 13.9, P = .005).41Matsumato T. Esaki M. Fujisawa et al.Chromoendoscopy, NBI colonoscopy, and autofluoresence colonoscopy for detection of diminutive colorectal neoplasia in FAP.Dis Colon Rectum. 2009; 52: 1160-1165Crossref PubMed Scopus (26) Google Scholar However, unlike in hereditary nonpolyposis colon cancer syndrome, polyps are not subtle in FAP; hence, additional detection of small adenomas is unlikely to change overall management and referral for eventual colectomy. Further studies are warranted to determine the role, if any, of chromoendoscopy and other advanced imaging techniques in this patient population. Currently, it is not recommended for routine use. Compliance with screening and surveilla
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