Familial adenomatous polyposis

Familial adenomatous polyposis (FAP) is a dominantly inherited familial cancer syndrome characterized by an increased predisposition to colorectal cancer and other benign and malignant extra-colonic lesions. FAP has been linked to germline mutations of the adenomatous polyposis coli (APC) gene that encodes a protein with 2,843 amino acids that has important functions in the regulation of cell growth. A genotype-phenotype correlation has also been observed between mutations in the APC gene and polyp phenotype. We review the clinical and genetic features of this disorder and provide information on the diagnostic approaches and treatment options available for this disease.     

Familial adenomatous polyposis

ClinicalHistoryA41-year-oldfemalewasadmittedintoNanFangHospitalforsevereabdominalpainwithbloody-mucoidstoolforamonth.Thesymptomsstartedayearagowithoutobviouscausesandshedidnothaveanysystemictreatment.Thepatientfeltfatigueandlossofweightforthelastthre...     

Familial adenomatous polyposis and lung cancer

A 43-year-old man presented with a lung nodule 19 years after undergoing a total colectomy for familial adenomatous polyposis (FAP). There had been no evidence of malignant transformation in the colectomy specimen, and current gastrointestinal investigation did not reveal evidence of tumor. Pathological analysis of the lung nodule demonstrated adenocarcinoma of the lung of the fetal type. This is the first reported case of a lung neoplasm in a patient with FAP. The development of an unusual lung tumor in a patient with FAP, a condition associated with other extracolonic tumors, suggests that there may be an association between the two conditions. © 1995 Wiley-Liss, Inc.     

FAP with concurrent duodenal adenomatous polyposis and carcinoid tumor

We report a patient with familial adenomatous polyposis (FAP) who developed duodenal adenomatosis with high-grade dysplasia and a periampullary carcinoid tumor several years after total colectomy. Only two prior case reports exist revealing carcinoid tumors in association with FAP. No genetic basis exists explaining the link between FAP and carcinoid tumors. However, the presence of two rare entities in the same patient might suggest an association and further research may be indicated.     

Familial adenomatous polyposis of the colon

Familial adenomatous polyposis (FAP) is a well-defined autosomal dominant predisposition to the development of polyposis in the colon and rectum at unusually early ages. The first symptoms of FAP are diarrhea and blood in the stool. Weight loss and weaknesses occur after the development of advanced tumour. The incidence of the FAP disorder is one per 10000 newborns. There are high levels of heterogeneity with regard to the number and timing of the occurrence of polyps. The classical form of FAP is characterized by the presence of more than 100 polyps, which appear in the second decade of life. The average time of occurrence of polyps is 15 years. The earliest symptoms of polyposis have been observed in a three-year-old child. The polyps are characterized by large potential for the development towards malignant tumour. Malignancy can occur from late childhood onwards. Attenuated adenomatous polyposis coli is characterized by a more benign course of disease in contrast to classical FAP. The occurrence of FAP is associated with mutations in the APC tumour suppressor gene, which was described in 1991. The APC gene is located on chromosome 5q21 and is involved in cell proliferation control. A recessive form of adenomatous polyposis is caused by mutations in the base excision repair gene - MUTYH gene. The MUTYH gene is involved in repairing DNA lesions as a result of oxidative DNA damage. MUTYH associated polyposis (MAP) is a predisposition to the development of polyps of the colon but the number of polyps is lower in comparison to classical FAP. The high risks of cancer observed in these two diseases make them important medical issues. Molecular studies of colonic polyposis have been performed in Poland for over fifteen years. A DNA Bank for Polish FAP patients was established at the Institute of Human Genetics in Poznan in which DNA samples from 600 FAP families have been collected.     

家族性腺瘤性息肉病18例报道

探讨家族性腺瘤性息肉病的临床特点和治疗问题。方法 对1984-2002年收治的18例病人进行回顾性分析。结果 有家族史者9例,癌变8例。手术方式:全结肠直肠切除8例,其中回肠造口2例,回肠储袋肛管吻合6例;结肠次全切除6例,其中回肠直肠吻合5例,升结肠肛管吻合1例;结肠部分切除2例;Miles术1例,结肠会阴造口1例。结论 认识该病的临床特点,根据息肉的分布特点和有无癌变等选择不同的手术方式,首选结直肠全切回肠储袋肛管吻合术。     

构建血清蛋白质质谱模型判别家族性腺瘤性息肉病与散发性肠腺瘤

目的 筛选家族性腺瘤性息肉病(FAP)的特异表达蛋白,构建判别FAP与散发性肠腺瘤的血清蛋白指纹图谱诊断模型.方法 采集19例FAP和16例散发性肠腺瘤患者的血清,以表面增强激光解吸电离飞行时间质谱仪(SELDI-MS-TOF)和阴离子CM01蛋白质芯片检测并筛选两组对象间的血清差异表达蛋白质峰,以支持向量机方法构建判别模型.结果 FAP与散发性肠腺瘤相比,P<0.01的蛋白质峰有6个,其中质荷比为5640、3160、4180和4290的蛋白质峰在FAP中高表达,质荷比为3940和3400的蛋白质峰在散发性肠腺瘤患者中高表达.以质倚比分别为5640、3160和4290的蛋白质峰为基础,联合质荷比为3940、13 750和4300的蛋白质峰所建立的模型判别效果最佳,对FAP与散发性肠腺瘤的判别准确率分别为94.7%和93.7%.结论 SELDI-TOF-MS能有效筛选FAP与散发性肠腺瘤的差异表达蛋白,支持向量机方法所建立的质谱模型判别效果较好,为进一步研究FAP的分子发病机制提供了切入点.     

Familial adenomatous polyposis: not all masses are desmoids

Familial adenomatous polyposis (FAP) is a multi-system disease characterised by the development of hundreds to thousands of colorectal adenomas which inevitably progress to carcinoma without treatment. It is commonly associated with extra colonic lesions including osteomas, epidermoid cysts and desmoid tumours. Desmoid tumours are troublesome due to their size and bulk and are a significant cause of morbidity and mortality in FAP. This series highlights three cases in which patients with FAP developed masses thought initially to be manifestations of the condition. Further investigation in fact demonstrated neurofibromatosis type 1 in all three patients. All masses in FAP patients cannot be assumed to be disease related (desmoid, osteoma, epidermoid cyst or carcinoma).     

Clinical management of familial adenomatous polyposis

Familial adenomatous polyposis is a generalized growth disorder. It manifests itself in a catastrophic way with the inevitable development of colorectal cancer if left untreated. The aim of clinical management should be to detect this disease at its earliest possible stage by treatment of the family as a unit and identification of those at risk with appropriate screening. Early surgical intervention with, most commonly, colectomy with ileorectal anastomosis or, in more advanced cases, with colectomy, rectal mucosectomy and ileoanal pouch procedure is appropriate. Following colorectal cancer the major risks of death from this disease include upper gastrointestinal cancer, desmoid tumour and a number of other malignancies throughout the body. The exact magnitude of the risk of malignant degeneration of these extracolonic manifestations is as yet uncertain. Surveillance is required particularly for upper gastrointestinal adenomas, as there is a significant risk for the development of duodenal carcinoma and it is obvious that prophylactic colectomy alone does not cure this disease predictably. The role of a familial polyposis registry in managing these patients is important not only in maintaining compliance with surveillance and therefore early detection of the disease but also in educating the family members and gaining long-term follow-up data on these cases to more accurately define the risk of death from extracolonic malignancy.     

Familial Adenomatous Polyposis (FAP) and Other Polyposis Syndromes

There have been significant advances in our knowledge about the molecular changes that precede and accompany the development of inherited predispositions to colorectal cancer. In this review the clinical relationship to the molecular changes associated with the polyposis syndromes is presented. The aim is to put into context the diverse findings that have been shown to be associated with the development of colorectal cancer in persons who harbor a predisposition to develop disease at unusually early ages. The main focus will be on familial adenomatous polyposis as it serves as a model disease and is the most extensively studied of all of the polyposis syndromes. In addition some information is provided that explains the relationship between a germline change in one gene and what consequences that can have for a particular cell and the development of disease.     

Detection of novel mitochondrial mutations in cytochrome C oxidase subunit 1 (COX1) in patients with familial adenomatous polyposis (FAP)

Familial adenomatous polyposis (FAP) is an Autosomal dominant inherited disorder and a rare form‌ of colorectal cancer (CRC) that is characterized by     

Familial adenomatous polyposis: the practical applications of clinical and molecular screening

Familial adenomatous polyposis (FAP) is an autosomal dominant condition mostly due to a mutation of the APC gene on the chromosome 5q. Carriers have an almost 100% chance of developing colorectal cancer after having multiple (typically 100s to 1000s) of adenomatous polyps. It is usually readily identified through this phenotype of multiple adenomas. Correlations between the location of the family-specific mutation on the APC gene and clinical manifestations of the disease are of some assistance in clinical management, though there is heterogeneity in clinical course even between family members with the same mutation. FAP is important to recognize, as there are diseasespecific management implications with respect to offering mutational analysis of the APC (and perhaps other) genes for predictive testing of other family members, endoscopic diagnostic procedures, surveillance planning, and surgical management. Extra-colonic manifestations, including duodenal polyposis, desmoid disease and other tumours, can dominate clinical care after colectomy. The inheritable and lethal nature of the disease, together with the availability of effective treatment strategies, makes a sensitive clinical and psychosocial approach important to maximize compliance and good outcomes for all members of affected families.     

Familial adenomatous polyposis at the Tel Aviv Medical Center: demographic and clinical features

Familial adenomatous polyposis (FAP) is an uncommon, but widespread genetic disorder that develops multiple colonic adenomatous polyps and, if untreated, can lead to large bowel cancer. Little is known about its occurrence and characteristics in the Israeli population. Aims: To evaluate FAP prevalence, phenotypic manifestations and compliance for diagnosis and follow-up in our registry. Methods: Since 1993 approximately one-half of FAP patients in Israel have been seen and followed-up by us before and/or after colectomy. They and their families were encouraged to have mutation analysis, genetic and/or endoscopic screening. Results: 37 pedigrees were identified, including 2 non-Jewish. The Jewish ethnic distribution was similar to that of the general population and the point prevalence rate estimated as 28.4/one million Jewish inhabitants. There were 461 first-degree relatives at-risk for FAP. Genetic screening was completed and successful in 28 pedigrees (87.5%), and 73 FAP patients entered the registry. Marked intra-familial phenotypic variations with minimal disease manifestation were noted in 11 patients belonging to 4 pedigrees. Cancer occurred in 15.1% (11 patients), in 10 before FAP diagnosis or during follow-up elsewhere, but one non-compliant patient developed duodenal cancer. One other patient died from a massive, neglected, intra-abdominal desmoid. Compliance for evaluation and follow-up of pedigree members and individual FAP patients was inadequate in 29% and 27%, respectively. Conclusions: FAP occurs in the Israeli Jewish population at the expected rate, but is inadequately recognized in non-Jews. The inadequate compliance for screening and post-surgical follow-up needs to be addressed by educating the public, health care workers and Health Insurers.     

A novel pathogenic germline mutation in the adenomatous polyposis coli gene in a Tunisian family with FAP

Familial adenomatous polyposis (FAP) is an autosomal dominant disorder which typically presents with colorectal cancer in early adult life, secondary to extensive adenomatous polyps of the colon. In addition to the colonic manifestations, the syndrome presents several extracolonic features including, congenital hypertrophy of the retinal pigment, osteomata and desmoid tumors. In this study, we aimed to investigate the clinical and genetic features in a Tunisian family with FAP. Sequence of the APC gene (Adenomatous Polyposis Coli) revealed a novel mutation (c.2016-2017 del TA) in exon 15, present in all affected individuals in an heterozygous state. The frameshift mutation generates a premature stop codon at amino acid 677 of the APC protein (p. H672Qfs X5). The unaffected family members did not harbor this mutation, however, a first degree relative of the patient aged of 32 year-old was phenotypically normal but carries the c.2016-2017 del TA mutation. This discrepancy can be explained by the effect of modifier gene which can affect the expressivity of the disease.     

Hepatoblastoma and familial adenomatous polyposis

Eleven children have been identified as having hepatoblastoma and a family history of adenomatous polyposis, and 14 additional instances of this association have been collected from the literature. Among the 11 survivors of hepatoblastoma in the combined series, adenomatous lesions have been sought in seven and detected in six patients at ages 7 to 25 years. Five of these patients also have congenital hypertrophy of the retinal pigment epithelium, a marker for carriers of the polyposis gene. These findings strengthen the association between hepatoblastoma and familial adenomatous polyposis and have led to the establishment of the Hepatoblastoma-Adenomatous Polyposis Registry.     

Gonadal mosaicism and familial adenomatous polyposis

De novo mutations in the adenomatous polyposis coli (APC) gene are estimated to constitute approximately 25% of familial adenomatous polyposis (FAP) cases. A small percentage of these arise in the mosaic form, affecting only a subset of cells in the affected individual. A family is described here whereby an unaffected mother with no detectible mutation in APC, transmitted the identical APC c.4729G>T (p.Glu1577X) mutation to two children. A third child, with the same APC allelic haplotype received a normal APC allele, suggesting that the mutation originated in the gonadal tissues of the mother. These results underscore the utility of mutation-specific genetic testing for the parents and siblings of a proband of an adult-onset disease, even if the proband appears to have a de novo mutation. Parents who test negative for the mutation should be counseled about the possibility of having another affected child due to gonadal mosaicism.     

Familial adenomatous polyposis and changes in the gut microbiota: New insights into colorectal cancer carcinogenesis

Patients with familial adenomatous polyposis (FAP), an autosomal dominant hereditary colorectal cancer syndrome, have a lifetime risk of developing cancer of nearly 100%. Recent studies have pointed out that the gut microbiota could play a crucial role in the development of colorectal adenomas and the consequent progression to colorectal cancer. Some gut bacteria, such as Fusobacterium nucleatum, Escherichia coli, Clostridium difficile, Peptostreptococcus, and enterotoxigenic Bacteroides fragilis, could be implicated in colorectal carcinogenesis through different mechanisms, including the maintenance of a chronic inflammatory state, production of bioactive tumorigenic metabolites, and DNA damage. Studies using the adenomatous polyposis coli^Min/+ mouse model, which resembles FAP in most respects, have shown that specific changes in the intestinal microbial community could influence a multistep progression, the intestinal “adenoma-carcinoma sequence”, which involves mucosal barrier injury, low-grade inflammation, activation of the Wnt pathway. Therefore, modulation of gut microbiota might represent a novel therapeutic target for patients with FAP. Administration of probiotics, prebiotics, antibiotics, and nonsteroidal anti-inflammatory drugs could potentially prevent the progression of the adenoma-carcinoma sequence in FAP. The aim of this review was to summarize the best available knowledge on the role of gut microbiota in colorectal carcinogenesis in patients with FAP.