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Molecular Aspects of Medicine Oct 2019The present article summarizes recent developments in the characterization of genetic predisposition to colorectal cancer (CRC). The main themes covered include new... (Review)
Review
The present article summarizes recent developments in the characterization of genetic predisposition to colorectal cancer (CRC). The main themes covered include new hereditary CRC and polyposis syndromes, non-CRC hereditary cancer genes found mutated in CRC patients, strategies used to identify novel causal genes, and review of candidate genes that have been proposed to predispose to CRC and/or colonic polyposis. We provide an overview of newly described genes and syndromes associated with predisposition to CRC and polyposis, including: polymerase proofreading-associated polyposis, NTHL1-associated polyposis, mismatch repair gene biallelic inactivation-related adenomatous polyposis (including MSH3- and MLH3-associated polyposes), GREM1-associated mixed polyposis, RNF43-associated serrated polyposis, and RPS20 mutations as a rare cause of hereditary nonpolyposis CRC. The implementation of next generation sequencing approaches for genetic testing has exposed the presence of pathogenic germline variants in genes associated with hereditary cancer syndromes not traditionally linked to CRC, which may have an impact on genetic testing, counseling and surveillance. The identification of new hereditary CRC and polyposis genes has not deemed an easy endeavor, even though known CRC-related genes explain a small proportion of the estimated familial risk. Whole-genome sequencing may offer a technology for increasing this proportion, particularly if applied on pedigree data allowing linkage type of analysis. The final section critically surveys the large number of candidate genes that have been recently proposed for CRC predisposition.
Topics: Adenomatous Polyposis Coli; Alleles; Biomarkers; Colorectal Neoplasms; Colorectal Neoplasms, Hereditary Nonpolyposis; Genetic Predisposition to Disease; Genetic Variation; Germ-Line Mutation; Humans
PubMed: 30862463
DOI: 10.1016/j.mam.2019.03.001 -
The American Journal of Gastroenterology Feb 2015This guideline presents recommendations for the management of patients with hereditary gastrointestinal cancer syndromes. The initial assessment is the collection of a... (Review)
Review
This guideline presents recommendations for the management of patients with hereditary gastrointestinal cancer syndromes. The initial assessment is the collection of a family history of cancers and premalignant gastrointestinal conditions and should provide enough information to develop a preliminary determination of the risk of a familial predisposition to cancer. Age at diagnosis and lineage (maternal and/or paternal) should be documented for all diagnoses, especially in first- and second-degree relatives. When indicated, genetic testing for a germline mutation should be done on the most informative candidate(s) identified through the family history evaluation and/or tumor analysis to confirm a diagnosis and allow for predictive testing of at-risk relatives. Genetic testing should be conducted in the context of pre- and post-test genetic counseling to ensure the patient's informed decision making. Patients who meet clinical criteria for a syndrome as well as those with identified pathogenic germline mutations should receive appropriate surveillance measures in order to minimize their overall risk of developing syndrome-specific cancers. This guideline specifically discusses genetic testing and management of Lynch syndrome, familial adenomatous polyposis (FAP), attenuated familial adenomatous polyposis (AFAP), MUTYH-associated polyposis (MAP), Peutz-Jeghers syndrome, juvenile polyposis syndrome, Cowden syndrome, serrated (hyperplastic) polyposis syndrome, hereditary pancreatic cancer, and hereditary gastric cancer.
Topics: Adenomatous Polyposis Coli; Colorectal Neoplasms, Hereditary Nonpolyposis; Disease Management; Gastrointestinal Neoplasms; Genetic Testing; Hamartoma Syndrome, Multiple; Humans; Intestinal Polyposis; Neoplastic Syndromes, Hereditary; Peutz-Jeghers Syndrome
PubMed: 25645574
DOI: 10.1038/ajg.2014.435 -
Best Practice & Research. Clinical... 2022Familial adenomatous polyposis (FAP) and MUTYH-associated polyposis (MAP) are rare inherited polyposis syndromes with a high colorectal cancer (CRC) risk. Therefore,... (Review)
Review
Familial adenomatous polyposis (FAP) and MUTYH-associated polyposis (MAP) are rare inherited polyposis syndromes with a high colorectal cancer (CRC) risk. Therefore, frequent endoscopic surveillance including polypectomy of relevant premalignant lesions from a young age is warranted in patients. In FAP and less often in MAP, prophylactic colectomy is indicated followed by lifelong endoscopic surveillance of the retained rectum after (sub)total colectomy and ileal pouch after proctocolectomy to prevent CRC. No consensus is reached on the right type and timing of colectomy. As patients with FAP and MAP nowadays have an almost normal life-expectancy due to adequate treatment of colorectal polyposis, challenges in the management of FAP and MAP have shifted towards the treatment of duodenal and gastric adenomas as well as desmoid treatment in FAP. Whereas up until recently upper gastrointestinal surveillance was mostly diagnostic and patients were referred for surgery once duodenal or gastric polyposis was advanced, nowadays endoscopic treatment of premalignant lesions is widely performed. Aiming to reduce polyp burden in the colorectum as well as in the upper gastrointestinal tract, several chemopreventive agents are currently being studied.
Topics: Adenomatous Polyposis Coli; Adenomatous Polyps; Colorectal Neoplasms; Humans; Stomach Neoplasms
PubMed: 35988966
DOI: 10.1016/j.bpg.2022.101793 -
Archives of Pathology & Laboratory... Nov 2019Familial adenomatous polyposis (FAP) is a rare genetic disorder with autosomal dominant inheritance, defined by numerous adenomatous polyps, which inevitably progress to... (Review)
Review
CONTEXT.—
Familial adenomatous polyposis (FAP) is a rare genetic disorder with autosomal dominant inheritance, defined by numerous adenomatous polyps, which inevitably progress to colorectal carcinoma unless detected and managed early. Greater than 70% of patients with this syndrome also develop extraintestinal manifestations, such as multiple osteomas, dental abnormalities, and a variety of other lesions located throughout the body. These manifestations have historically been subcategorized as Gardner syndrome, Turcot syndrome, or gastric adenocarcinoma and proximal polyposis of the stomach. Recent studies, however, correlate the severity of gastrointestinal disease and the prominence of extraintestinal findings to specific mutations within the adenomatous polyposis coli gene (), supporting a spectrum of disease as opposed to subcategorization. Advances in immunohistochemical and molecular techniques shed new light on the origin, classification, and progression risk of different entities associated with FAP.
OBJECTIVE.—
To provide a comprehensive clinicopathologic review of neoplastic and nonneoplastic entities associated with FAP syndrome, with emphasis on recent developments in immunohistochemical and molecular profiles of extraintestinal manifestations in the thyroid, skin, soft tissue, bone, central nervous system, liver, and pancreas, and the subsequent changes in classification schemes and risk stratification.
DATA SOURCES.—
This review will be based on peer-reviewed literature and the authors' experiences.
CONCLUSIONS.—
In this review we will provide an update on the clinicopathologic manifestations, immunohistochemical profiles, molecular features, and prognosis of entities seen in FAP, with a focus on routine recognition and appropriate workup of extraintestinal manifestations.
Topics: Adenomatous Polyposis Coli; Adenomatous Polyposis Coli Protein; Brain Neoplasms; Colorectal Neoplasms; Gardner Syndrome; Humans; Immunohistochemistry; Mutation; Neoplastic Syndromes, Hereditary; Prognosis; Skin
PubMed: 31070935
DOI: 10.5858/arpa.2018-0570-RA -
BJS Open May 2023Inheritance patterns show familial clustering of gastrointestinal cancers, and multiple germline conditions have now been identified that predispose to colorectal,... (Review)
Review
BACKGROUND
Inheritance patterns show familial clustering of gastrointestinal cancers, and multiple germline conditions have now been identified that predispose to colorectal, gastric, and pancreatic cancers.
METHODS
A narrative review based on recent relevant literature was conducted.
RESULTS
Lynch syndrome, formerly known as hereditary non-polyposis colorectal cancer, increases the risk of several abdominal cancers, with the highest population prevalence. Familial adenomatous polyposis and some of the more infrequent polyposis syndromes have distinct characteristics affecting various organ-specific cancer risks. Hereditary gastric and pancreatic cancer syndromes include those also causing colorectal cancer, while additional genetic disorders predisposing only to upper gastrointestinal malignancies have been recognized more recently. Diagnosing and managing hereditary cancer syndromes requires multidisciplinary expertise and may be best managed in tertiary centres, with a need to consider patient preference and ensure shared decision-making.
CONCLUSION
Several germline conditions predispose to colorectal, gastric, and pancreatic cancer, which inform identification, surveillance regimens, prevention, cascade screening, counselling, and surgical management. The authors describe developments in the hereditary origin of colorectal, gastric, and pancreatic cancer with current recommendations in surveillance and surgical management.
Topics: Humans; Adenomatous Polyposis Coli; Neoplastic Syndromes, Hereditary; Colorectal Neoplasms; Gastrointestinal Neoplasms; Pancreatic Neoplasms
PubMed: 37165697
DOI: 10.1093/bjsopen/zrad023 -
International Journal of Molecular... Jan 2023Colorectal cancer is one of the most common tumors, and genetic predisposition is one of the key risk factors in the development of this malignancy. Lynch syndrome and... (Review)
Review
Colorectal cancer is one of the most common tumors, and genetic predisposition is one of the key risk factors in the development of this malignancy. Lynch syndrome and familial adenomatous polyposis are the best-known genetic diseases associated with hereditary colorectal cancer. However, some other genetic disorders confer an increased risk of colorectal cancer, such as Li-Fraumeni syndrome ( gene), -associated polyposis ( gene), Peutz-Jeghers syndrome ( gene), Cowden syndrome ( gene), and juvenile polyposis syndrome ( and genes). Moreover, the recent advances in molecular techniques, in particular Next-Generation Sequencing, have led to the identification of many new genes involved in the predisposition to colorectal cancers, such as , , , , , , and . In this review, we summarized the past and more recent findings in the field of cancer predisposition genes, with insights into the role of the encoded proteins and into the associated genetic disorders. Furthermore, we discussed the possible clinical utility of genetic testing in terms of prevention protocols and therapeutic approaches.
Topics: Humans; Genetic Predisposition to Disease; Adenomatous Polyposis Coli; Neoplastic Syndromes, Hereditary; Colorectal Neoplasms, Hereditary Nonpolyposis; Genetic Testing; Colorectal Neoplasms
PubMed: 36768460
DOI: 10.3390/ijms24032137 -
Orphanet Journal of Rare Diseases Oct 2009Familial adenomatous polyposis (FAP) is characterized by the development of many tens to thousands of adenomas in the rectum and colon during the second decade of life.... (Review)
Review
Familial adenomatous polyposis (FAP) is characterized by the development of many tens to thousands of adenomas in the rectum and colon during the second decade of life. FAP has an incidence at birth of about 1/8,300, it manifests equally in both sexes, and accounts for less than 1% of colorectal cancer (CRC) cases. In the European Union, prevalence has been estimated at 1/11,300-37,600. Most patients are asymptomatic for years until the adenomas are large and numerous, and cause rectal bleeding or even anemia, or cancer develops. Generally, cancers start to develop a decade after the appearance of the polyps. Nonspecific symptoms may include constipation or diarrhea, abdominal pain, palpable abdominal masses and weight loss. FAP may present with some extraintestinal manifestations such as osteomas, dental abnormalities (unerupted teeth, congenital absence of one or more teeth, supernumerary teeth, dentigerous cysts and odontomas), congenital hypertrophy of the retinal pigment epithelium (CHRPE), desmoid tumors, and extracolonic cancers (thyroid, liver, bile ducts and central nervous system). A less aggressive variant of FAP, attenuated FAP (AFAP), is characterized by fewer colorectal adenomatous polyps (usually 10 to 100), later age of adenoma appearance and a lower cancer risk. Some lesions (skull and mandible osteomas, dental abnormalities, and fibromas on the scalp, shoulders, arms and back) are indicative of the Gardner variant of FAP. Classic FAP is inherited in an autosomal dominant manner and results from a germline mutation in the adenomatous polyposis (APC) gene. Most patients (~70%) have a family history of colorectal polyps and cancer. In a subset of individuals, a MUTYH mutation causes a recessively inherited polyposis condition, MUTYH-associated polyposis (MAP), which is characterized by a slightly increased risk of developing CRC and polyps/adenomas in both the upper and lower gastrointestinal tract. Diagnosis is based on a suggestive family history, clinical findings, and large bowel endoscopy or full colonoscopy. Whenever possible, the clinical diagnosis should be confirmed by genetic testing. When the APC mutation in the family has been identified, genetic testing of all first-degree relatives should be performed. Presymptomatic and prenatal (amniocentesis and chorionic villous sampling), and even preimplantation genetic testing is possible. Referral to a geneticist or genetic counselor is mandatory. Differential diagnoses include other disorders causing multiple polyps (such as Peutz-Jeghers syndrome, familial juvenile polyps or hyperplastic polyposis, hereditary mixed polyposis syndromes, and Lynch syndrome). Cancer prevention and maintaining a good quality of life are the main goals of management and regular and systematic follow-up and supportive care should be offered to all patients. By the late teens or early twenties, colorectal cancer prophylactic surgery is advocated. The recommended alternatives are total proctocolectomy and ileoanal pouch or ileorectal anastomosis for AFAP. Duodenal cancer and desmoids are the two main causes of mortality after total colectomy, they need to be identified early and treated. Upper endoscopy is necessary for surveillance to reduce the risk of ampullary and duodenal cancer. Patients with progressive tumors and unresectable disease may respond or stabilize with a combination of cytotoxic chemotherapy and surgery (when possible to perform). Adjunctive therapy with celecoxib has been approved by the US Food and Drug Administration and the European Medicines Agency in patients with FAP. Individuals with FAP carry a 100% risk of CRC; however, this risk is reduced significantly when patients enter a screening-treatment program.
Topics: Adenomatous Polyposis Coli; Animals; Female; Humans; Male
PubMed: 19822006
DOI: 10.1186/1750-1172-4-22 -
Journal of the National Cancer Institute Aug 2017Adenomatous polyposis coli (APC) is widely accepted as a tumor suppressor gene highly mutated in colorectal cancers (CRC). Mutation and inactivation of this gene is a... (Review)
Review
Adenomatous polyposis coli (APC) is widely accepted as a tumor suppressor gene highly mutated in colorectal cancers (CRC). Mutation and inactivation of this gene is a key and early event almost uniquely observed in colorectal tumorigenesis. Alterations in the APC gene generate truncated gene products, leading to activation of the Wnt signaling pathway and deregulation of multiple other cellular processes. It has been a mystery why most patients with CRC retain a truncated APC protein, but accumulating evidence suggest that these C terminally truncated APC proteins may have gain of function properties beyond the well-established loss of tumor suppressive function. Here, we will review the evidence for both the loss of function and the gain of function of APC truncations and how together they contribute to CRC initiation and progression.
Topics: Adenomatous Polyposis Coli Protein; Cell Transformation, Neoplastic; Colorectal Neoplasms; Genetic Predisposition to Disease; Humans; Models, Genetic; Mutation; Tumor Suppressor Proteins; Wnt Signaling Pathway; beta Catenin
PubMed: 28423402
DOI: 10.1093/jnci/djw332 -
Cells Sep 2020The Wnt/β-catenin signaling pathway exerts integral roles in embryogenesis and adult homeostasis. Aberrant activation of the pathway is implicated in growth-associated... (Review)
Review
The Wnt/β-catenin signaling pathway exerts integral roles in embryogenesis and adult homeostasis. Aberrant activation of the pathway is implicated in growth-associated diseases and cancers, especially as a key driver in the initiation and progression of colorectal cancer (CRC). Loss or inactivation of Adenomatous polyposis coli (APC) results in constitutive activation of Wnt/β-catenin signaling, which is considered as an initiating event in the development of CRC. Increased Wnt/β-catenin signaling is observed in virtually all CRC patients, underscoring the importance of this pathway for therapeutic intervention. Prior studies have deciphered the regulatory networks required for the cytoplasmic stabilisation or degradation of the Wnt pathway effector, β-catenin. However, the mechanism whereby nuclear β-catenin drives or inhibits expression of Wnt target genes is more diverse and less well characterised. Here, we describe a brief synopsis of the core canonical Wnt pathway components, set the spotlight on nuclear mediators and highlight the emerging role of chromatin regulators as modulators of β-catenin-dependent transcription activity and oncogenic output.
Topics: Adenomatous Polyposis Coli Protein; Carcinogenesis; Chromatin; Colorectal Neoplasms; Disease Progression; Epigenesis, Genetic; Gene Expression Regulation, Neoplastic; Histones; Humans; Proteasome Endopeptidase Complex; Proteolysis; Signal Transduction; TCF Transcription Factors; Transcription, Genetic; Wnt Proteins; beta Catenin
PubMed: 32961708
DOI: 10.3390/cells9092125 -
Gut Mar 2020Heritable factors account for approximately 35% of colorectal cancer (CRC) risk, and almost 30% of the population in the UK have a family history of CRC. The...
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).
Heritable factors account for approximately 35% of colorectal cancer (CRC) risk, and almost 30% of the population in the UK have a family history of CRC. The quantification of an individual's lifetime risk of gastrointestinal cancer may incorporate clinical and molecular data, and depends on accurate phenotypic assessment and genetic diagnosis. In turn this may facilitate targeted risk-reducing interventions, including endoscopic surveillance, preventative surgery and chemoprophylaxis, which provide opportunities for cancer prevention. This guideline is an update from the 2010 British Society of Gastroenterology/Association of Coloproctology of Great Britain and Ireland (BSG/ACPGBI) guidelines for colorectal screening and surveillance in moderate and high-risk groups; however, this guideline is concerned specifically with people who have increased lifetime risk of CRC due to hereditary factors, including those with Lynch syndrome, polyposis or a family history of CRC. On this occasion we invited the UK Cancer Genetics Group (UKCGG), a subgroup within the British Society of Genetic Medicine (BSGM), as a partner to BSG and ACPGBI in the multidisciplinary guideline development process. We also invited external review through the Delphi process by members of the public as well as the steering committees of the European Hereditary Tumour Group (EHTG) and the European Society of Gastrointestinal Endoscopy (ESGE). A systematic review of 10 189 publications was undertaken to develop 67 evidence and expert opinion-based recommendations for the management of hereditary CRC risk. Ten research recommendations are also prioritised to inform clinical management of people at hereditary CRC risk.
Topics: Adenomatous Polyposis Coli; Colonoscopy; Colorectal Neoplasms; Colorectal Neoplasms, Hereditary Nonpolyposis; DNA Glycosylases; Family Health; Humans; Intestinal Polyposis; Ireland; Life Style; Neoplastic Syndromes, Hereditary; Peutz-Jeghers Syndrome; Population Surveillance; Referral and Consultation; Risk Factors; United Kingdom
PubMed: 31780574
DOI: 10.1136/gutjnl-2019-319915