{ "schemaVersion": 2, "eyebrow": "Hereditary GI Oncology", "title": "Familial Adenomatous Polyposis", "summary": "Familial adenomatous polyposis requires early APC-directed family testing, intensive colorectal surveillance, timely risk-reducing colectomy, and lifelong upper gastrointestinal assessment with ampullary visualization to prevent colorectal and duodenal malignancy.", "seoDescription": "Physician guide to APC-associated familial adenomatous polyposis: genetic diagnosis, colorectal surveillance, colectomy triggers, and upper GI management.", "clinicalQuestion": "How should physicians diagnose, surveil, and select risk-reducing surgery for patients with familial adenomatous polyposis?", "specialty": "Gastroenterology", "audience": "U.S. physicians and medical trainees", "tags": [ "familial adenomatous polyposis", "FAP", "APC pathogenic variant", "attenuated FAP", "colectomy", "duodenal polyposis", "Spigelman classification" ], "keyTakeaways": [ "Confirm APC-associated polyposis with germline APC testing and use the familial pathogenic variant for predictive testing of at-risk relatives. [21]", "Begin colorectal surveillance in classic FAP at age 10-15 years; confirmed FAP surveillance intervals can be individualized to colon phenotype, generally every 1-3 years. [21][2]", "Move from endoscopic management to colectomy when adenomas larger than 10 mm cannot be reasonably removed, adenoma burden accelerates, high-grade dysplasia is present, or the colon cannot be adequately surveyed. [21]", "Perform EGD with ampullary visualization by age 20-25 years or before colon surgery; use Spigelman staging for duodenal adenomatous burden and consider complete small-bowel evaluation with advanced disease. [21][11]", "Do not use NSAIDs or erlotinib as substitutes for colectomy: adenoma regression has been observed, but no FDA-approved chemopreventive agent has established prevention of subsequent cancer. [21]" ], "sections": [ { "id": "establish-diagnosis-and-family-risk", "eyebrow": "Diagnosis", "heading": "Establish APC-associated polyposis and identify relatives who need early surveillance", "intro": "Genotype directs predictive testing and determines whether intensive surveillance should begin in childhood.", "paragraphs": [ "Establish an APC-associated polyposis condition by identifying a heterozygous germline pathogenic APC variant. Classic and attenuated FAP are APC-associated phenotypes; gastric adenocarcinoma and proximal polyposis of the stomach is also included in the APC-associated spectrum. [21]", "A clinical phenotype of more than 100 colorectal adenomatous polyps supports classic FAP; fewer than 100 adenomas with a family history of FAP also supports the diagnosis. Attenuated FAP generally has fewer than 100 adenomas, later polyp development, and a more proximal colonic distribution. [10][17]", "For a known familial APC pathogenic variant, offer predictive molecular testing to at-risk relatives early enough to determine whether childhood surveillance is necessary. In confirmed FAP after predictive testing, colonic surveillance should normally begin at age 12-14 years; GeneReviews recommends colonoscopy every 1-2 years beginning at age 10-15 years for classic FAP. [2][21]", "When a patient has multiple colorectal adenomas but no germline APC or MUTYH variant, retain concern for APC mosaicism rather than labeling the condition sporadic without further assessment. Low-level APC mosaicism accounts for a substantial fraction of otherwise unexplained adenomatous polyposis, and first-degree relatives may warrant colonoscopic risk assessment at referral or again at age 50 years, although this latter recommendation lacked guideline consensus. [1][2]" ], "bullets": [ "Use the known familial APC variant for predictive testing rather than relying on serial endoscopy alone when informative testing is available. [21]", "In a patient with 10 or more metachronous adenomas after clearing lesions larger than 5 mm, perform annual colonoscopy; if subsequent examinations show no polyp 10 mm or larger, extend to every 2 years. [2]" ], "subsections": [], "table": { "caption": "Phenotype and surveillance distinctions in APC-associated polyposis. [2][10][21]", "columns": [ "Clinical setting", "Actionable interpretation", "Next surveillance action" ], "rows": [ [ "Classic FAP phenotype", "More than 100 colorectal adenomatous polyps supports clinical FAP. [10]", "Begin colonoscopy at age 10-15 years; repeat every 1-2 years. [21]" ], [ "Attenuated FAP phenotype", "Usually fewer than 100 adenomas, often with later onset and proximal predominance. [17]", "Begin colorectal surveillance in late adolescence. [21]" ], [ "Confirmed FAP by predictive testing", "APC pathogenic variant identifies patients at high colorectal and upper GI risk. [21]", "Colonic surveillance may be individualized to phenotype every 1-3 years. [2]" ], [ "Multiple metachronous adenomas after clearance", "At least 10 metachronous adenomas indicates substantial recurrent adenoma burden. [2]", "Annual colonoscopy; extend to every 2 years only if no subsequent lesion is 10 mm or larger. [2]" ] ] } }, { "id": "manage-colorectal-burden", "eyebrow": "Colorectal cancer prevention", "heading": "Use colonoscopic burden and histology to time colectomy", "intro": "The operative decision is driven by endoscopic controllability and dysplasia, not by a fixed polyp count alone.", "paragraphs": [ "Continue colonoscopic surveillance while adenomas remain endoscopically manageable, but refer for colectomy planning when multiple adenomas larger than 10 mm cannot reasonably be removed, adenoma number increases substantially between examinations, high-grade dysplasia is identified, or innumerable diminutive adenomas prevent adequate colonic surveillance. Limited endoscopic access or inability to adhere to surveillance is also a relative indication for colectomy. [21]", "Colectomy is the preventive standard for classic FAP because it reduces colorectal cancer risk. The operation should be selected and timed through a colorectal surgery team able to integrate rectal polyp burden, endoscopic feasibility, patient reliability for lifelong surveillance, and competing extracolonic disease. [21]", "Surveillance materially changes outcomes. In a systematic review, symptomatic FAP presentation was associated with colorectal cancer in 33.6%-66.2% of patients versus 3.8%-9.4% among those under surveillance; surveillance delayed colorectal cancer development by up to 16 years and improved mean survival by up to 12 years. [9]", "Do not defer indicated surgery because pharmacologic polyp regression occurs. NSAIDs and erlotinib have reduced adenoma burden in studies, but no agent is FDA-approved for FAP chemoprevention because reduction in later cancer risk remains unclear. Colectomy or proctocolectomy remains initial standard care. [21][16]" ], "bullets": [ "Escalate to operative planning after high-grade dysplasia, rapid interval increase in adenoma burden, or failure to clear adenomas larger than 10 mm endoscopically. [21]", "Treat inability to maintain adequate colonoscopic surveillance as an oncologic risk factor, not solely a logistical issue. [21]", "Continue surveillance after prophylactic colorectal surgery because adenocarcinoma and pouch neoplasia have been reported after prophylactic operations. [1]" ], "subsections": [], "table": { "caption": "Colorectal decision triggers for FAP. [21]", "columns": [ "Finding", "Interpretation", "Action" ], "rows": [ [ "Adenomas controlled by endoscopic resection", "Colon remains adequately surveillable. [21]", "Continue phenotype-directed colonoscopic surveillance. [2][21]" ], [ "Multiple adenomas larger than 10 mm not reasonably removable", "Endoscopic clearance is inadequate. [21]", "Refer for risk-reducing colectomy planning. [21]" ], [ "High-grade dysplasia", "Advanced neoplastic change raises urgency of definitive colorectal management. [21]", "Proceed with colorectal surgical evaluation for colectomy. [21]" ], [ "Innumerable diminutive adenomas, poor access, or inability to comply with surveillance", "Adequate cancer surveillance cannot be ensured. [21]", "Treat as a relative indication for colectomy. [21]" ] ] } }, { "id": "upper-gi-surveillance", "eyebrow": "Duodenal and gastric risk", "heading": "Perform lifelong upper GI surveillance with ampullary assessment", "intro": "After colorectal risk reduction, duodenal and periampullary neoplasia become central management targets.", "paragraphs": [ "Perform esophagogastroduodenoscopy with visualization of the ampulla of Vater by age 20-25 years or before colon surgery. Upper GI surveillance should not omit ampullary inspection, because duodenal and ampullary adenomas can progress independently of the colorectal phenotype. [21][14]", "Stage duodenal adenomatosis using the Spigelman classification, which is recommended for risk stratification and has demonstrated excellent interobserver reliability among experienced endoscopists (intraclass correlation coefficient 0.95, 95% CI 0.91-0.98). In advanced Spigelman stage, consider complete small-bowel visualization. [11][21]", "The clinical stakes are substantial: duodenal adenomas develop in an estimated 88%-98% of patients with FAP, and estimated duodenal cancer risk reaches 18% by age 75 years. High-risk duodenal adenoma features are reported in 50% of patients by age 70 years. [9]", "Endoscopically remove duodenal polyps larger than 10 mm when feasible. Repeated endoscopic resection and ampullectomy can downstage severe disease, but high-grade dysplasia or unresectable lesions should trigger evaluation for radical surgery, including duodenectomy or pancreaticoduodenectomy when malignancy is threatening. [14][12]" ], "bullets": [ "Document the ampullary appearance at each surveillance examination because ampullary abnormalities increased from 18.3% at first EGD to 47.4% by the fourth EGD in one surveillance cohort. [12]", "Do not rely on Spigelman stage alone to exclude cancer risk: ampullary abnormality and patient age were among predictors of high-grade dysplasia in a large surveillance series. [12]", "Continue duodenal surveillance after total gastrectomy when anatomy permits; gastrectomy does not eliminate duodenal cancer risk. [14]" ], "subsections": [ { "heading": "Gastric polyposis that changes management", "paragraphs": [ "During EGD, characterize gastric polyps and obtain histology when dysplasia is suspected. In a 337-patient FAP cohort, the 10-year cumulative gastric cancer incidence was 0% with no polyps, 1% with polyps, 6% with low-grade dysplasia, 11% with polyps 2 cm or larger, and 20% with high-grade dysplasia; high-grade dysplasia and polyps at least 2 cm were strongly associated with gastric cancer. [15]", "Refer patients with gastric high-grade dysplasia or cancer for surgical evaluation. Total gastrectomy with Roux-en-Y esophagojejunostomy is indicated when gastric polyps harbor high-grade dysplasia or cancer. [14]" ], "bullets": [] } ], "table": { "caption": "Upper GI escalation in FAP. [11][12][14][15][21]", "columns": [ "Endoscopic or histologic finding", "Risk interpretation", "Next action" ], "rows": [ [ "FAP without prior upper GI assessment", "Upper GI neoplasia requires dedicated surveillance. [21]", "EGD with ampullary visualization by age 20-25 years or before colon surgery. [21]" ], [ "Advanced duodenal adenomatosis", "Spigelman staging supports risk stratification; advanced disease may justify complete small-bowel visualization. [11][21]", "Increase expert endoscopic assessment and consider complete small-bowel evaluation. [21]" ], [ "Duodenal polyp larger than 10 mm", "Larger lesions warrant therapeutic endoscopic consideration. [14]", "Remove endoscopically when feasible. [14]" ], [ "High-grade dysplasia or unresectable duodenal/ampullary lesion", "Malignancy risk may exceed what iterative endoscopic therapy can control. [12]", "Refer for radical surgical evaluation, including duodenectomy or pancreaticoduodenectomy. [12]" ], [ "Gastric high-grade dysplasia or gastric cancer", "High-grade dysplasia carries a 20% 10-year cumulative gastric cancer incidence in one cohort. [15]", "Obtain surgical evaluation; total gastrectomy is indicated for gastric polyps with high-grade dysplasia or cancer. [14]" ] ] } }, { "id": "extraintestinal-risk", "eyebrow": "Extracolonic disease", "heading": "Recognize desmoid disease and pediatric hepatoblastoma risk", "intro": "Extraintestinal manifestations can alter surgical timing and prompt targeted evaluation.", "paragraphs": [ "Maintain a low threshold to evaluate new abdominal mass symptoms in FAP for intra-abdominal desmoid tumor, particularly after abdominal surgery. Desmoid tumors are locally aggressive and infiltrative but rarely metastasize; reported FAP incidence is 10%-20%, and family history, surgery, and APC mutation are recognized risk factors. [19][18]", "For children known to carry an APC pathogenic variant or at 50% familial risk, annual hepatoblastoma screening from birth through age 5 years has been recommended. [10]", "Do not automatically infer FAP from an isolated desmoid tumor. Although 5%-15% of desmoids are associated with FAP, reported yield of identifying FAP among patients with intra-abdominal or truncal desmoids without prior history was 4%-5%; a selective colonoscopy or genetic-testing strategy is therefore more appropriate than universal screening. [19]" ], "bullets": [ "In FAP with a new mesenteric or retroperitoneal mass, include desmoid-type fibromatosis in the immediate differential because it can invade adjacent structures without metastatic spread. [19]", "In an isolated desmoid presentation, prioritize FAP assessment when multiple desmoids or other clinical features increase pretest probability. [19]" ], "subsections": [], "table": { "caption": "Targeted extracolonic actions in FAP. [10][18][19]", "columns": [ "Clinical scenario", "Action", "Reason" ], "rows": [ [ "Known APC pathogenic variant or 50% FAP risk, birth through age 5 years", "Perform annual hepatoblastoma screening. [10]", "This is the recommended pediatric surveillance window. [10]" ], [ "FAP with postoperative or new abdominal mass symptoms", "Evaluate for intra-abdominal desmoid tumor. [18][19]", "FAP-associated desmoids are frequently intra-abdominal and surgery is a risk factor. [18][19]" ], [ "Isolated intra-abdominal or truncal desmoid without known FAP", "Use selective, phenotype-driven colonoscopy or genetic testing rather than universal FAP screening. [19]", "Detection yield for occult FAP is reported at 4%-5%. [19]" ] ] } }, { "id": "longitudinal-care", "eyebrow": "Care coordination", "heading": "Build surveillance around irreversible risk and procedural feasibility", "intro": "Management requires parallel colorectal, upper GI, surgical, and family-based follow-up.", "paragraphs": [ "At each surveillance encounter, document three variables that change management: colorectal adenoma size and removability, interval change in adenoma number, and dysplasia grade. These determine whether continued endoscopic control remains reasonable or colectomy should be advanced. [21]", "Coordinate colorectal and upper GI planning rather than treating them as sequential problems. EGD should occur by age 20-25 years or before colon surgery, and advanced duodenal disease may require complete small-bowel visualization or referral for therapeutic endoscopy and surgery. [21][12]", "After colorectal surgery, continue surveillance of remaining at-risk gastrointestinal mucosa and maintain upper GI monitoring. Post-prophylactic adenocarcinomas and neoplastic change in ileal pouches have been reported, while duodenal cancer becomes a major malignancy after colectomy. [1][14]" ], "bullets": [ "Refer early to a multidisciplinary hereditary cancer program when colectomy is being considered, when high-grade dysplasia is identified, or when duodenal/ampullary lesions require advanced resection. [12][21]", "Separate adenoma-burden reduction from proven cancer prevention when discussing medication: no chemopreventive agent is FDA-approved for FAP. [21]" ], "subsections": [], "table": { "caption": "Longitudinal checkpoint framework for FAP. [1][12][21]", "columns": [ "Checkpoint", "Required decision", "Escalation trigger" ], "rows": [ [ "Colonoscopy", "Can the colon still be completely and reliably surveilled? [21]", "Unremovable adenomas larger than 10 mm, high-grade dysplasia, accelerating burden, or inadequate surveillance. [21]" ], [ "EGD with ampullary visualization", "What is the duodenal and ampullary neoplasia burden? [11][21]", "Advanced disease, high-grade dysplasia, or unresectable lesions. [12]" ], [ "After prophylactic colorectal surgery", "Which residual mucosa remains at risk? [1]", "New neoplasia in retained or pouch mucosa requires continued endoscopic management. 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Verify recommendations against current guidance and patient-specific factors.", "citations": [ { "number": 1, "title": "Guidelines for the management of hereditary colorectal cancer ... - Gut", "detail": "gut.bmj.com", "url": "https://gut.bmj.com/content/gutjnl/early/2019/11/28/gutjnl-2019-319915.full.pdf", "authors": "gut.bmj.com", "host": "gut.bmj.com", "snippet": "D, Axilbund J, et al. Clinical characteristics of multiple colorectal adenoma patients without germline APC or MYH mutations. J Clin Gastroenterol 2016;50:584–8. 205 Kallenberg FGJ, Latchford A, Lips NC, et al. Duodenal adenomas in patients with multiple colorectal adenomas without germline APC or M", "score": 0.6907474 }, { "number": 2, "title": "Guidelines for the management of hereditary colorectal cancer from the British Society of Gastroenterology (BSG)/Association of Coloproctology of Great Britain and Ireland (ACPGBI)/United Kingdom Cancer Genetics Group (UKCGG) | Gut", "detail": "gut.bmj.com", "url": "https://gut.bmj.com/content/69/3/411", "authors": "gut.bmj.com", "host": "gut.bmj.com", "snippet": "## Familial adenomatous polyposis\n\nFAP is defined by the presence of pathogenic variants in the APC gene with a prevalence of about 1/8500. It is a dominantly inherited multisystem cancer predisposition syndrome with a characteristic phenotype characterised by colorectal and upper GI polyposis.\n\n###", "score": 0.6496014 }, { "number": 3, "title": "The Use and Interpretation of Commercial APC Gene Testing for ...", "detail": "www.nejm.org", "url": "https://www.nejm.org/doi/full/10.1056/NEJM199703203361202", "authors": "www.nejm.org", "host": "www.nejm.org", "snippet": "Familial adenomatous polyposis is an autosomal dominant disease caused by a germ-line mutation of the adenomatous polyposis coli (APC ) gene", "score": 0.5481178 }, { "number": 4, "title": "The Molecular Basis of Turcot's Syndrome", "detail": "www.nejm.org", "url": "https://www.nejm.org/doi/full/10.1056/NEJM199503303321302", "authors": "www.nejm.org", "host": "www.nejm.org", "snippet": "In familial adenomatous polyposis there is a germ-line alteration of the adenomatous polyposis coli (APC) gene; mutations of the gene can be", "score": 0.54492307 }, { "number": 5, "title": "Primary Chemoprevention of Familial Adenomatous Polyposis with ...", "detail": "www.nejm.org", "url": "https://www.nejm.org/doi/full/10.1056/NEJMoa012015", "authors": "www.nejm.org", "host": "www.nejm.org", "snippet": "Familial adenomatous polyposis is an autosomal dominant syndrome caused by a germ-line mutation of the adenomatous polyposis coli (APC) gene", "score": 0.54303354 }, { "number": 6, "title": "The management of gastric polyps - Gut", "detail": "gut.bmj.com", "url": "https://gut.bmj.com/content/gutjnl/59/9/1270.full.pdf", "authors": "gut.bmj.com", "host": "gut.bmj.com", "snippet": "Familial adenomatous polyposis (FAP) is caused by a germline mutation in the adenomatous polyposis coli APC gene on chromosome 5q21 and has an", "score": 0.528169 }, { "number": 7, "title": "Multiple Colorectal Adenomas, Classic Adenomatous Polyposis ...", "detail": "www.nejm.org", "url": "https://www.nejm.org/doi/full/10.1056/NEJMoa025283", "authors": "www.nejm.org", "host": "www.nejm.org", "snippet": "familial adenomatous polyposis ・ no germ-line APC mutation can be found in some patients ・ molecular methods should be used to classify disease in patients", "score": 0.51603514 }, { "number": 8, "title": "British Society of Gastroenterology guidelines on colorectal ... - Gut", "detail": "gut.bmj.com", "url": "https://gut.bmj.com/content/75/3/442", "authors": "gut.bmj.com", "host": "gut.bmj.com", "snippet": "IBD and hereditary CRC syndromes\n\nIBD and hereditary CRC syndromes such Lynch, familial adenomatous polyposis, MYH-associated polyposis (MAP), serrated polyposis syndrome and hamartomatous polyposis syndromes are independently associated with an increased risk of CRC.100 126 127 It is uncertain whet", "score": 0.486015 }, { "number": 9, "title": "Role of endoscopy in patients with familial adenomatous polyposis", "detail": "fg.bmj.com", "url": "https://fg.bmj.com/content/13/e1/e72", "authors": "fg.bmj.com", "host": "fg.bmj.com", "snippet": "The studies in the systemic review from the United Kingdom (UK) demonstrated an incidence of CRC in 33.6%–66.2% in FAP patients presenting symptomatically compared with 3.8%–9.4% in those FAP under surveillance with a delay in CRC development of up to 16 years and mean survival improved by up to12 y", "score": 0.73322314 }, { "number": 10, "title": "Familial Adenomatous Polyposis - an overview | ScienceDirect Topics", "detail": "sciencedirect.com", "url": "https://sciencedirect.com/topics/pharmacology-toxicology-and-pharmaceutical-science/familial-adenomatous-polyposis", "authors": "sciencedirect.com", "host": "sciencedirect.com", "snippet": "The American Gastroenterological Association55 recommends surveillance of individuals with a known APC mutation or who are at 50% risk of FAP based on a family history. This surveillance includes the following:\n\nAnnual screening for hepatoblastoma from birth to 5 years of age\n\nSigmoidoscopy every 1–", "score": 0.6780931 }, { "number": 11, "title": "Validation of the Endoscopic Part of the Spigelman... : Official journal of the American College of Gastroenterology | ACG", "detail": "journals.lww.com", "url": "https://journals.lww.com/ajg/fulltext/2022/02000/validation_of_the_endoscopic_part_of_the_spigelman.27.aspx", "authors": "journals.lww.com", "host": "journals.lww.com", "snippet": "Title: Validation of the Endoscopic Part of the Spigelman... : Official journal of the American College of Gastroenterology | ACG\n# Validation of the Endoscopic Part of the Spigelman Classification for Evaluating Duodenal Adenomatosis in Familial Adenomatous Polyposis: A Prospective Study of Interra", "score": 0.6549173 }, { "number": 12, "title": "Surveillance of Duodenal Polyposis in Familial... : Diseases of the Colon & Rectum", "detail": "journals.lww.com", "url": "https://journals.lww.com/dcrjournal/fulltext/2017/11000/surveillance_of_duodenal_polyposis_in_familial.6.aspx?Ppt=Article%7Cdcrjournal%3A2017%3A11000%3A00006%7C10.1097%2Fdcr.0000000000000903%7C", "authors": "journals.lww.com", "host": "journals.lww.com", "snippet": "Title: Surveillance of Duodenal Polyposis in Familial... : Diseases of the Colon & Rectum\n# Surveillance of Duodenal Polyposis in Familial Adenomatous Polyposis: Should the Spigelman Score Be Modified? Duodenal polyposis is a manifestation of adenomatous polyposis that predisposes to duodenal or amp", "score": 0.6490677 }, { "number": 13, "title": "Spigelman stage IV duodenal polyposis does not precede most duodenal cancer cases in patients with familial adenomatous polyposis - ScienceDirect", "detail": "www.sciencedirect.com", "url": "https://www.sciencedirect.com/science/article/abs/pii/S0016510718329006", "authors": "www.sciencedirect.com", "host": "www.sciencedirect.com", "snippet": "### Gastrointest Endosc\n\n### Upper gastrointestinal cancer in patients with familial adenomatous polyposis\n\n### Lancet\n\n### Periampullary adenomas and adenocarcinomas in familial adenomatous polyposis: cumulative risks and APC gene mutations\n\n### Gastroenterology\n\n### Features of duodenal cancer in ", "score": 0.6479992 }, { "number": 14, "title": "Endoscopic Surveillance of Duodenal Polyposis... : ACG Case Reports Journal", "detail": "journals.lww.com", "url": "https://journals.lww.com/acgcr/fulltext/2020/08000/endoscopic_surveillance_of_duodenal_polyposis.14.aspx", "authors": "journals.lww.com", "host": "journals.lww.com", "snippet": "Title: Endoscopic Surveillance of Duodenal Polyposis... : ACG Case Reports Journal\n# Endoscopic Surveillance of Duodenal Polyposis After Total Gastrectomy in Familial Adenomatous Polyposis. The lifetime incidence of duodenal polyposis in familial adenomatous polyposis (FAP) approaches 100%, and duod", "score": 0.6437107 }, { "number": 15, "title": "Gastric polyposis and risk of gastric cancer in patients with familial adenomatous polyposis", "detail": "www.sciencedirect.com", "url": "https://www.sciencedirect.com/science/article/abs/pii/S1091255X24005924", "authors": "www.sciencedirect.com", "host": "www.sciencedirect.com", "snippet": "management of people with suspected or confirmed hereditary syndromes related to increased risk of upper GI cancers, with particular reference to indication for genetic testing, age of start of endoscopic screening, best practice in relation to endoscopic surveillance and indication for surgery. [..", "score": 0.6227582 }, { "number": 16, "title": "Combination of Sulindac and Eflornithine Delays... - Lippincott", "detail": "journals.lww.com", "url": "https://journals.lww.com/dcrjournal/fulltext/2022/04000/combination_of_sulindac_and_eflornithine_delays.14.aspx", "authors": "journals.lww.com", "host": "journals.lww.com", "snippet": "Colectomy and proctocolectomy are the initial standard of care for patients with familial adenomatous polyposis. Pharmacotherapy to prevent the progression of", "score": 0.61668247 }, { "number": 17, "title": "Detecting and managing hereditary colorectal cancer syndromes in ...", "detail": "www.ccjm.org", "url": "https://www.ccjm.org/content/ccjom/79/11/787.full.pdf", "authors": "www.ccjm.org", "host": "www.ccjm.org", "snippet": "■ ■Familial Adenomatous Polyposis Familial adenomatous polyposis is caused by mutations in the APC gene. Its prevalence is 2.29 to 3.2 per 100,000 individuals.25,26 Genetics of familial adenomatous polyposis APC is the only gene known to cause famil-ial adenomatous polyposis. Mutations in APC are in", "score": 0.60610276 }, { "number": 18, "title": "[PDF] Jejunal Desmoid Tumor after Roux-en-Y Gastric Bypass Mimicking ...", "detail": "www.facs.org", "url": "https://www.facs.org/media/rmqfmwjz/14-pinson-jejunal-desmoid-tumor.pdf", "authors": "www.facs.org", "host": "www.facs.org", "snippet": "9. Perez Y, Webber JD, Edelman D. Mesenteric fibromatosis of the small bowel mesentery after gastric bypass surgery. CRSLS. 2015. 10. Nieuwenhuis MH, Lefevre JH, Bülow S, et al. Family histo­ ry, surgery, and APC mutation are risk factors for desmoid tumors in familial adenomatous polyposis: an int", "score": 0.5414337 }, { "number": 19, "title": "Jejunal Desmoid Tumor After Roux-en-Y Gastric Bypass Mimicking GIST | ACS", "detail": "www.facs.org", "url": "https://www.facs.org/for-medical-professionals/news-publications/journals/case-reviews/issues/v4n6/14-pinson-jejunal-desmoid-tumor", "authors": "www.facs.org", "host": "www.facs.org", "snippet": "Intraabdominal desmoid tumors (also known as desmoid-type fibromatosis or aggressive fibromatosis) are locally aggressive neoplasms arising primarily in the mesentery or retroperitoneum. These tumors infiltrate adjacent tissues but rarely metastasize.8,9 Patients with familial adenomatous polyposis ", "score": 0.31434566 }, { "number": 20, "title": "Hereditary Gastrointestinal Cancer Syndromes: Role of Imaging in ...", "detail": "pubs.rsna.org", "url": "https://pubs.rsna.org/doi/10.1148/rg.2019180185", "authors": "pubs.rsna.org", "host": "pubs.rsna.org", "snippet": "FAP is an autosomal dominant condition caused by germline mutations in the adenomatous polyposis coli (APC) gene on chromosome 5q21, although one-third of new", "score": 0.26461646 }, { "number": 21, "title": "APC-Associated Polyposis Conditions - GeneReviews® - NCBI Bookshelf", "detail": "www.ncbi.nlm.nih.gov", "url": "https://www.ncbi.nlm.nih.gov/portal/utils/pageresolver.fcgi?recordid=6a03c15f7c2ed0724dcfbb9f", "authors": "www.ncbi.nlm.nih.gov", "host": "www.ncbi.nlm.nih.gov", "snippet": "Title: APC-Associated Polyposis Conditions - GeneReviews® - NCBI Bookshelf\n# *APC*-Associated Polyposis Conditions. *APC*-associated polyposis conditions include (classic or attenuated) familial adenomatous polyposis (FAP) and gastric adenocarcinoma and proximal polyposis of the stomach (GAPPS). The", "score": 0.8588255 }, { "number": 22, "title": "Genetic characterization of the APC locus involved in familial adenomatous polyposis - Gastroenterology", "detail": "www.gastrojournal.org", "url": "https://www.gastrojournal.org/article/0016-5085(91)90472-W/abstract", "authors": "www.gastrojournal.org", "host": "www.gastrojournal.org", "snippet": "# Genetic characterization of the APC locus involved in familial adenomatous polyposis. a,b,c,d,e,f ∙ Barbara Weiffenbach. a,b,c,d,e,f ∙ … ∙ Thomas Melot. a,b,c,d,e,f ∙ Anne Vassal. a,b,c,d,e,f ∙ Katherine Falls. a,b,c,d,e,f ∙ Remy J. a,b,c,d,e,f ∙ Roland Parc. a,b,c,d,e,f ∙ Louise Strong. a,b,c,d,e", "score": 0.7785319 }, { "number": 23, "title": "ASCO/SSO Review of Current Role of Risk-Reducing Surgery in ...", "detail": "ascopubs.org", "url": "https://ascopubs.org/doi/10.1200/JCO.2005.04.5260", "authors": "ascopubs.org", "host": "ascopubs.org", "snippet": "Primary chemoprevention of familial adenomatous polyposis with sulindac. Noncytotoxic drug therapy for intra-abdominal desmoid tumor in", "score": 0.56690645 }, { "number": 24, "title": "[PDF] Colorectal Cancer Glossary - CDC Archive", "detail": "archive.cdc.gov", "url": "https://archive.cdc.gov/www_cdc_gov/genomics/gtesting/file/print/fbr/CC_Glossary.pdf", "authors": "archive.cdc.gov", "host": "archive.cdc.gov", "snippet": "Giardiello FM, Yang VW, Hylind LM, Krush AJ, Petersen GM, Trimbath JD, et al. 2002. Pri­ mary chemoprevention of familial adenomatous polyposis with sulindac. N Engl J Med 346:1054-1059. Gryfe R, Kim H, Hsieh ET, Aronson MD, Holowaty EJ, Bull SB, et al. 2000. Tumor microsatel-342:69-77. Genetic Arch", "score": 0.67192334 } ], "publishedAt": "2026-09-16T00:55:24.613283+00:00", "updatedAt": "2026-09-16T00:55:24.613283+00:00", "readingMinutes": 6, "slug": "familial-adenomatous-polyposis" }