polypose adénomateuse familiale atténuée
Le risque de cancer reste très important. Together with the fact that both germ-line and sporadic APC mutations cluster in the central region of the APC gene, this points to a dominant negative effect of certain APC mutants. 32 - N° 5P2 - p. 158-165 - Iconography : La polypose adénomateuse familiale (PAF) atténuée : une entité à connaître - EM|consulte Three patients with the I1307K allele were detected, each of Ashkenazi descent. The I1307K allele was found in 6.1% of unselected Ashkenazi No clearly pathogenic MTH1 or OGG1 mutations were identified. Six patients with multiple adenomas and eight patients with polyposis had biallelic germline MYH variants. Elle est caractérisée par le développement de centaines ou de milliers de polypes dans la paroi interne du côlon et du rectum dès l’adolescence. Total cell RNA was isolated from cultured lymphoblasts, and an in vitro protein synthesis assay was used to detect APC mutations. a polypose adénomateuse familiale (PAF), décrite depuis 1721, reste le chef de file des polyposes digestives, par sa fréquence et ses caractéristiques phénotypiques (tapis de polypes colorectaux, adénomes duodénaux, association au syndrome de Gardner). Polypose atténuée Skin and visceral neoplasms were tested for microsatellite instability and immunohistochemical status of mismatch repair (MMR), APC and MYH proteins. Sans ce suivi, tout peut très vite s’arrêter, c’est pourquoi le sérieux s’impose. Two novel AXIN2 variants were detected in one patient with multiple adenomas, but no clearly pathogenic mutation. Low frequency ofAXIN2 mutations and high frequency ofMUTYH mutations in patients with multiple polyposis, Colonoscopic Withdrawal Times and Adenoma Detection During Screening Colonoscopy, Germline MYH mutations in a clinic-based series of Canadian multiple colorectal adenoma patients, Similar Colorectal Cancer Risk in Patients with Monoallelic and Biallelic Mutations in the MYH Gene Identified in a Population with Adenomatous Polyposis, LA POLYPOSE FAMILIALE ADENOMATEUSE (PAF) ATTENUEE : UNE ENTITE A CONNAÎTRE. This report presents an interesting case of association between MYH-associated polyposis and sebaceous gland tumors. In contrast, nine different MUTYH mutations were detected in eight patients, including four novel mutations. Polypose adénomateuse familiale La polypose adénomateuse familiale (PAF) est une maladie héréditaire, autosomique dominante, dont la pénétrance est complète (la présence de la mutation entraîne quasi constamment l’apparition du phénotype). In contrast, mutant APC gene products that are associated with attenuated polyposis (codon 386 or 1465) interfered only weakly with wild-type APC activity. [dictionnaire.academie-medecine.fr] image info × Source. The tumour in Patient A was detected during evaluation of non-specific abdominal complaints. Présentes dans tous les organismes vivants, elles sont le support du patrimoine génétique héréditaire. In all AAPC kindreds, a predominance of right-sided colorectal adenomas and rectal polyp sparing was observed. We Upper gastrointestinal examination revealed fundic gland polyps in 15, gastric or duodenal adenomas in 4, and periampullary carcinoma in 1.Conclusion. Our aim was to determine their respective frequency, risk factors, and cumulative risk. Site gratuit de codes CIM-10 et CCAM, compatible AMELI, dédié au PMSI. Gastroentérologie Clinique et Biologique - Vol. There was a significant difference between the two groups with respect to the median duration of the examination (18.9 minutes in the control group vs. 27.1 minutes for the study group, P < 0.001). Our objective was to determine the significance of MYH mutations in a series of Canadian patients with multiple adenomas. In addition, four patients with truncating APC variants in exon 9 or in the 3′ part of the gene were identified. Familial adenomatous polyposis has been linked to germline mutations in the APC tumor suppressor gene. We report on a 42-year-old woman ascertained for a large desmoid tumor of the anterior chest wall with pleural involvement, which persistently recurred despite a decade of treatment including hormone therapy, chemotherapy, and surgery. To determine the frequency, mutation spectrum and phenotype of the recently described autosomal recessive MUTYH-associated polyposis (MAP), we performed a systematic search for MUTYH (MYH) mutations by sequencing the complete coding region of the gene in 329 unselected APC mutation-negative index patients with the clinical diagnosis of familial adenomatous polyposis (FAP) or attenuated FAP (AFAP). genotyped I1307K carriers and non-carriers and their first-degree relatives. In this large community-based gastroenterology practice, we observed greater rates of detection of adenomas among endoscopists who had longer mean times for withdrawal of the colonoscope. Spontaneous disappearance of the tumor was later noted after 1 year without any treatment and confirmed after 4 years of regular follow-up. The aim of this randomized prospective study was to determine whether a combination of chromoscopy and structure enhancement could increase the adenoma detection rate in high-risk patients. Les tumeurs malignes anorectales avec 61 cas (6,9%) occupaient la quatrième place après la maladie hémorroïdaire (45,6%), les anites (21,1%) et les fissures (13,9%). To further address the pathogenic significance of |1307K, we offered both a genetic test and a screening program to individuals considered to be at increased risk for colorectal cancer. Results: Molecular genetic analysis showed that 25 had biallelic mutations of the MYH gene. Tyrosine 82 is located in the pseudo-helix-hairpin-helix (HhH) motif and is predicted to function in mismatch specificity. Chromoscopy and structure enhancement diagnosed significantly more diminutive adenomas (< 5mm) in the right colon, compared with controls ( P = 0.039). Colorectal cancer fulfils the conditions required for mass screening. Studies in larger series of MAP patients are needed to investigate the risk of upper-gastro-intestinal malignancies and to determine further guidelines for endoscopical surveillance. La sensibilisation de la population et la prescription plus large de l'endoscopie digestive basse devraient permettre une meilleure prise en charge des patients. Vendredi 02 octobre 2015. The development of high-grade dysplasia (HGD) on duodenal or jejunal adenomas and of late-stage (stage IV) duodenal polyposis are major clinical events for familial adenomatous polyposis (FAP) patients. A total of 59 polyps were identified in 44 subjects. Rien ne sert de courir si l’on ne tient pas son suivi … N’oubliez pas, les médecins peuvent être des « magiciens » mais il est de notre responsabilité de les mettre en situation. AFAP is a phenotypically distinctive syndrome, differing from classic FAP by having fewer colonic adenomas that tend to be proximally distributed and flat rather than polypoid. The authors previously described a colon cancer-prone syndrome characterized by fewer adenomas (1–100), most located in the proximal colon, and upper gastrointestinal lesions, particularly fundic gland polyps and duodenal adenomas. Il s'agit d'une mutation bi-allélique, c'est-à-dire une mutation sur les deux gènes (d’origine paternelle et maternelle) chez les enfants malades. We compared the prevalence of polyps and their characteristics between carriers and noncarriers.Methods: Invitations to participate in a DNA and colonoscopy screening program were mailed, together with a family questionnaire, to 3540 households forming the Jewish Community in Ottawa. Le phénotype et le génotype de l'AFAP restent incertains. Endoscopic screening of the whole intestine should be carried out every two years for all MAP patients, starting from age 25-30 years. Heterozygous and homozygous MYH mutation carriers were both at high risk for synchronous cancers (24% in colorectum and 16% in the upper gastrointestinal tract), but did not demonstrate an increased risk for extradigestive tumors. The distribution of colonic adenomas also varied, with diffuse polyposis in 6 patients but relative polyp sparing in the more proximal colon in 6 others. We recorded the numbers, sizes, and histologic features of the neoplastic lesions detected during screening, as well as the duration of insertion and of withdrawal of the colonoscope during the procedure. This should help in the design of tailored clinical-management protocols in this subset of FAP patients. We screened for germline MYH mutations (by dHPLCO) in 20 clinic-based multiple adenoma patients who were adenomatous polyposis coli (APC) mutation-negative. Il est donc quelque peu capable de … Le nombre de polypes varie d’une dizaine à une centaine (en moyenne 30 polypes), prédominant au niveau du côlon proximal [2]. Cancer 1995;76:2427-33. Furthermore, with the exception of three prepubertal children all patients with mutations in codons 1445-1578 developed desmoid tumours. Few studies have determined whether or not the same genes harbour other, more common variants, which might have a lower penetrance and/or cause mild disease, perhaps indistinguishable from sporadic disease and accounting for a considerable proportion of the unexplained inherited risk of tumours in the general population. Upper gastrointestinal examination revealed fundic gland polyps in 15, gastric or duodenal adenomas in 4, and periampullary carcinoma in 1. Inactivation of the adenomatous polyposis coli (APC) gene product initiates colorectal tumorigenesis. In individuals with mutations in either region 2 or region 3, the average number of adenomas tended to be lower than those in individuals with mutations in region 1, although age at diagnosis was similar. A large proportion of non-FAP non-HNPCC patients with multiple colorectal adenomas have been reported to carry germline mutations on the MYH gene. La polypose adénomateuse associée à APC « polypose adénomateuse familiale » Génétique moléculaire Mutation du gène APC Transmission autosomique dominante Phénotype La polypose colorectale, profuse ou « atténuée » La polypose duodénale / adénoK duodénal Manifestations extradigestives Tumeurs desmoïdes In vitro analysis of the corresponding mutations in E.coli MutY revealed a reduction in the adenine glycosylase activity of the enzymes. Promouvoir et permettre le développement et la diffusion des recherches fondamentales biologiques, génétiques et thérapeutiques sur les polyposes familiales et les affections voisines; Faire connaître les résultats et les possibilités des différents traitements; Qu'est ce que la Polypose Adénomateuse Familiale. However; it is unclear whether the alteration predisposes to adenomas and whether the genetic information can be used in clinical practice. No difference was found in the percentage of biallelic mutation carriers between patients with 10-99 polyps or 100-1000 polyps (29% in both groups). Management should include genotyping of patients who are at risk, colonoscopic surveillance of genotypically positive persons, and prophylactic colectomy if several adenomas are found. Recently, however, DEFINITION : - Maladie héréditaire a transmission autosomique dominante, liée à la mutation du ... 2.2 PAF atténuée • < 100 polypes colorectaux, • Distribution proximale des polypes et cancers, polypes rectaux sont rares. Family history of colorectal cancer, or having familial adenomatous polyposis or Lynch syndrome. Bi-allelic germline mutations in the MUTYH gene give rise to multiple adenomas and an increased incidence of colorectal cancer. In conclusion, biallelic MUTYH mutations are the underlying genetic basis in a substantial fraction of patients with adenomatous polyposis. polyposis (FAP), a highly penetrant autosomal dominant disorder characterized Fifty percentage of the MAP patients had colorectal cancer at diagnosis. Polypose adénomateuse colique. Six of 20 (30%) patients carried pathogenic biallelic MYH mutations, 1 Y165C homozygote and 5 compound heterozygotes of other sequence variants. The patient underwent a surgical treatment. This relationship between certain extracolonic manifestations and site of the APC mutation points to a specific role of the APC protein in different tissues. A variant of FAP is attenuated adenomatous polyposis coli, which results from germ-line mutations in the 5′ and 3′ have studied a set of 164 patients with multiple colorectal adenomas and/or carcinoma and analyzed codons 1263–1377 (exon Attenuated familial adenomatous polyposis and Muir-Torre syndrome linked to compound biallelic constitutional MYH gene mutations.Peculiar dermatologic manifestations are present in several heritable gastrointestinal disorders. All affected members generated a 16-kDa polypeptide from the mutant allele, consistent with a 2-base pair deletion at the extreme 5' end of the APC gene. La polypose adénomateuse familiale atténuée (PAF atténuée) est un sous-type de la PAF. Il ne faut pas se laisser endormir et oublier qu’il y a la maladie et notamment le SUIVI à respecter. MYH-associated polyposis is a frequent inherited colorectal cancer predisposition with a strong dominance component. SAURIN, J.-C 1. The effect of variation in withdrawal times on lesion detection and the prevention of colorectal cancer in the context of widespread colonoscopic screening is not known. Histologically confirmed adenomatous polyps were diagnosed in 11.8% of carriers and 12.8% of non-carriers (P > 0.5). Polypose adénomateuse familiale — Polypose recto colique familiale Pour les articles homonymes, voir Polypose. Mutations were located in three different regions of the APC gene: (1) at the 5' end spanning exons 4 and 5, (2) within exon 9, and (3) at the 3' distal end of the gene. The 11-year-old daughter was carrier of the monoallelic constitutional mutation 379delC in the MYH gene; in the sister, the R168H MYH gene mutation was detected. In addition to three Ashkenazi patients with I1307K, we found seven patients with the E1317Q variant. There is increasing evidence that there exist germ-line variants of the APC gene that predispose to the development of multiple colorectal adenomas and carcinoma, but without the florid phenotype of classical FAP, and possibly with importance for colorectal cancer risk in the general population. Il s'agit le plus souvent d'une polypose adénomateuse atténuée (nombres de polypes colorectaux inférieur à 100) se révélant à l'âge adulte (45 ans environ). The current work reveals a reduced ability of the hMYH variants compared to wild-type (WT) hMYH to complement the activity of E.coli MutY in mutY((-)) E.coli. Aide au Codage CIM 10 polypose colique colon - CCAM et CIM10 en Français. AXIN2 and MUTYH genes were screened for germline mutations by PCR and direct sequencing in 39 unrelated patients with multiple adenomas or colorectal cancer without evidence of APC mutation nor mismatch repair defect. We found that the "third hit" probably initiated tumorigenesis. Colorectal cancers occurred predominantly in the rectosigmoid (80%) but also in the more proximal colon. 3' 15G) of the APC gene for germ-line variants. The I1307K allele of the APC gene has been shown to confer a modestly elevated risk of colorectal cancer in the Ashkenazi Jewish population (relative risk, 1.5-1.7). The usual manifestation of familial adenomatous polyposis (FAP) is hundreds or thousands of colonic adenomas. C'est une association de loi 1901, sans but lucratif et gérée exclusivement par des bénévoles.Ses objectifs sont les suivants: Une question sur les polyposes familiales? Both lesions presented the characteristic morphological and immunohistochemical features of pyloric adenoma, including the expression of MUC6. Polypose adénomateuse familiale atténuée. Here we report a mutation (T to A at APC nucleotide 3920) found in 6% of Ashkenazi Jews and about 28% of Ashkenazim with a family history of CRC. La polypose adénomateuse familiale (PAF) atténuée : une entité à connaître. During a median (+/- standard deviation) follow-up of 47.9 +/- 15.6 months, 35 patients with at least two consecutive examinations had 107 duodenojejunal examinations. The Escherichia coli adenine glycosylase MutY and its human homolog (hMYH) play an important role in the prevention of mutations associated with OG by removing misincorporated adenine residues from OG:A mismatches. Mutation of the APC gene and family history of FAP in a patient with apparently sporadic desmoid tumors Attenuated familial adenomatous polyposis (AFAP). To test our hypothesis, we obtained genotypic information on 81 family members with respect to seven polymorphic DNA markers previously shown to be linked to the locus for familial polyposis coli. Multilocus analysis of the data demonstrated genetic linkage (lod score, 5.58) between these markers and the locus responsible for the defined syndrome of colonic polyps or colorectal cancer in this kindred. Two well-defined syndromes, familial adenomatous polyposis (FAP) and hereditary non-polyposis colorectal cancer (HNPCC), account for up to 5% of the total new cases of CRC. The distribution of polyps was frequently right-sided in patients in proximal 5' families (P = 0.001). polypose adénomateuse familiale atténuée Une polypose adénomateuse familiale doit être suspectée dès qu’il existe plus de 10 adénomes synchrones (plus de 100 adénomes coliques pour la PAF et plus de 10 pour la polypose adénomateuse familiale atténuée). 225 families with FAP were screened for mutations. To assess the performance of screening colonoscopy in everyday practice, we conducted a study of the rates of detection of adenomas and the amount of time taken to withdraw the colonoscope among endoscopists in a large community-based practice. Durant la période de notre étude, 645 patients ont été examinés en anorectoscopie et 882 cas d'affections anorectales colligés. Variability in the number of colorectal adenomas was most apparent in individuals with mutations in region 1, and upper-gastrointestinal manifestations were more severe in them. In addition, duodenal adenomas and other extra-colonic manifestations have been described in MUTYH-associated polyposis (MAP) patients. traduzione di familial adenomatous polyposis nel dizionario Inglese - Francese, consulta anche , esempi, coniugazione, pronuncia The authors previously described a colon cancer-prone syndrome characterized by fewer adenomas (1-100), most located in the proximal colon, and upper gastrointestinal lesions, particularly fundic gland polyps and duodenal adenomas. Tumors from affected persons displayed excess somatic transversions of a guanine-cytosine pair to a thymine-adenine pair (G:C-->T:A) in the APC gene. In patients with the 5 base-pair deletion at codon 1309, gastrointestinal symptoms and death from colorectal cancer occurred about 10 years earlier than in patients with other mutations. The tumor appears when this constitutional mutation continues somatically on the other APC allele [30,31]. Results: Mutations that were proximal to codon 158 were found in 7 of 112 families (6%). Although the number of adenomas appears to be dependent on the number of mutated MYH alleles present in a patient, little is known on the relation of this number with cancer risk. Among patients with multiple adenomas, biallelic MYH mutations account for approximately 30% of APC mutation negative cases and two thirds of these carry mutations other than the "common" Y165C and G382D variants. Cox regression and linear regression analysis were used to determine risk factors for HGD development and the cumulative risk of stage IV duodenal polyposis, respectively. Elle a été décrite pour la première fois en 2002. Germ-line mutations in the base-excision-repair gene MYH have been associated with recessive inheritance of multiple colorectal adenomas. Le site de l'association vous décrit cette affection et son traitement The aim of this study was to further assess the contribution of AXIN2 and MUTYH to hereditary colorectal cancer susceptibility. We compared rates of detection of neoplastic lesions among gastroenterologists who had mean colonoscopic withdrawal times of less than 6 minutes with the rates of those who had mean withdrawal times of 6 minutes or more. Germline mutation in the adenomatous polyposis coli (APC) gene on chromosome 5 causes familial adenomatous polyposis. These positions are highly conserved in MutY across phylogeny. Sujets participants. Compliance must be over 50%. La polypose adénomateuse familiale présente une forme atténuée où les polypes sont moins nombreux, plus petits et apparaissent plus tard. of CRC (ref. Introduction: Desmoid tumors are rare entities, can occur at any age and may be located intra or extra-abdominal. Invitations to participate in a DNA and colonoscopy screening program were mailed, together with a family questionnaire, to 3540 households forming the Jewish Community in Ottawa. Here, we provide experimental evidence for a dominant negative effect of APC gene products associated with severe polyposis. We report here two cases of gastric adenomas of pyloric type diagnosed during the follow-up of familial adenomatous polyposis (FAP). Hépatogastroentérologie, pavillon 2C, centre hospitalier de Lyon-Sud, 165, chemin du Grand-Revoyet, 69495 Pierre-Bénite cedex, France. Colorectal cancer was found in 26 of the 40 patients with MAP (65%) within the age range 21 to 67 years (median 45). Clinical care of patients with biallelic MYH mutations should be similar to that of patients with classic or attenuated familial adenomatous polyposis. Alternative Meanings 415 alternative PAF meanings. Five novel germ-line APC mutations were identified in seven kindreds. exemple d'une famille [Familial adenomatous polyposis (FAP): integration of clinical and genetic parameters in the screening of subjects at risk. Traductions en contexte de "polypose" en français-allemand avec Reverso Context : Utilisation selon la revendication 6, dans laquelle la lésion précancéreuse est la polypose adénomateuse familiale ou une kératose actinique. Previously, biallelic mutations of hMYH have been identified in a British family (Family N) with symptoms characteristic of familial adenomatous polyposis (FAP), which is typically associated with mutations in the adenomatous polyposis coli (APC) gene. The pedigree revealed other isolated or familial adenomatous polyposis-associated cases of desmoid tumors. Sex, age at diagnosis of familial adenomatous polyposis, number of polyps at first examination of the colon, distribution of polyps, age at diagnosis of colorectal cancer, and location of colorectal cancer. This study evaluated the phenotype of 74 patients with familial adenomatous polyposis from 11 unrelated families with an identical 5-base pair deletion at codon 1309 of the APC gene. Risk of developing colorectal, breast and other cancers were compared between Another group of patients with multiple adenomas has no mutations in the APC gene, and their phenotype probably results from variation at a locus, or loci, elsewhere in the genome. A higher proportion of heterozygous gene carriers was found in the subgroup of colon cancer survivors (27%) than among asymptomatic individuals (8%, P < 0.02). distinctive variant of FAP [see comments]. These observations suggest that a dominant negative effect altering cell migration is exerted by the truncated APC protein present in the Min/+ mouse. We found no difference in enterocyte migration, proliferation, apoptosis, or beta-catenin levels in the Apc1638N mouse when compared to wild-type littermates bearing two normal Apc alleles. N3-AUTOINDEXEE. Mendelian tumour syndromes are caused by rare mutations, which usually lead to protein inactivation. Methods: La forme atténuée (AFAP) a été associée à des sites spécifiques de mutation du gène APC. About one-fifth (20%) of the 64 unrelated MAP patients harboured none of the 2 hot-spot missense mutations Y165C and/or G382D. The germline T-to-A transversion Objet: La polypose adénomateuse familiale est une maladie phénotypiquement hétérogène prédisposant au cancer colorectal. Both are caused by inherited mutations in the APC gene, and management includes genetic testing, colonoscopic surveillance, and prophylactic surgery for the relatives of index cases. Histologically confirmed adenomatous polyps were diagnosed in 11.8% of carriers and 12.8% of noncarriers (P > 0.5). Moreover, biallelic mutations in the base excision repair gene MUTYH have been associated with polyposis and early-onset colorectal cancer. These findings suggest that patients with MTS phenotype that include colonic polyposis should be screened for MYH gene mutations. - La polypose adénomateuse familiale atténuée (PAFA) est une variante moins grave de la PAF. La PAF est à … Rather than altering the function of the encoded protein, this mutation creates a small hypermutable region of the gene, indirectly causing cancer predisposition. Elle présente moins de polypes au niveau du côlon (<100), une présentation ultérieure d'adénomes et un cancer colorectal. stemming. Screenings rely on biennial testing in between 50 and 74average risk subjects. 32 - N° 5P2 - p. 158-165 - La polypose adénomateuse familiale (PAF) atténuée : une entité à connaître - EM consulte We compared the prevalence of polyps and their characteristics between carriers and noncarriers. Homozygous and compound heterozygous MYH mutations were identified in 40 patients (24%). La définition floue de la polypose adénomateuse familiale atténuée était surtout caractérisée par les faibles antécédents familiaux, un age d’apparition des polypes plus tardifs et l’absence de manifestations extra-coliques. At the first examination of the colon, 8 of 17 (47%) patients in proximal 5' families and 9 of 48 (19%) patients of similar ages in distal 5' families were found to have fewer than 100 adenomas (P = 0.029). J Clin Pathol 2006;59:1212-5. Elles regroupaient les cancers du rectum (4,2%) et les cancers de l'anus (2,7%). This rare histological lesion has been only recently described in this particular context and its clinical and pathological spectrum remains to be evaluated. Email: contact@polyposes-familiales.fr
Background & Aims: The |1307K allele of the APC gene has been shown to confer a modestly elevated risk of colorectal cancer in the Ashkenazi Jewish population (relative risk, 1.5–1.7). Pyloric adenoma belongs to the spectrum of gastric polyps associated with FAP; its prognosis and evolution remain to be evaluated. AAPC is recognized by the occurrence of <100 colonic adenomas and a later onset of colorectal cancer (age >40 years). Generalisation of screening has become a reality in France. familial adenomatous polyposis translation in English - French Reverso dictionary, see also 'familiar',familiarise',familiarity',familiarize', examples, definition, conjugation To read the full-text of this research, you can request a copy directly from the author. clinique. Other title. The position of the APC germline mutation appears to allow for the molecular differentiation between FAP and the attenuated variant in that the extreme 5' APC mutations are associated with the latter. Suspected mutations were confirmed by sequence analysis. As compared with colonoscopists with mean withdrawal times of less than 6 minutes, those with mean withdrawal times of 6 minutes or more had higher rates of detection of any neoplasia (28.3% vs. 11.8%, P<0.001) and of advanced neoplasia (6.4% vs. 2.6%, P=0.005). La polypose adénomateuse familiale, FAP est une maladie connue depuis longtemps, qui se caractérise par le développement de plusieurs centaines, voire plusieurs milliers de polypes adénomateux sur le colon et le rectum. Un membre de la famille peut présenter plus de 100 polypes alors qu'un autre peut n'en avoir qu'un seul. La polypose adénomateuse Familliale est une maladie rare, Devenez bénévoles, parlez de l'association autour de vous, faites un don... L'association a été créée en 1991 par des malades, pour des malades et leur famille. polyposis. Proctosigmoidoscopic examination of 51 family members identified only 2 with familial polyposis coli, which strongly predisposes those who have it to colorectal cancer and which is defined as the presence of more than 100 polyps in the colon.