Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0033036 (APC)
 10,214 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The clinical differentiation between hereditary nonpolyposis colorectal cancer (HNPCC) and attenuated familial adenomatous polyposis (AFAP) is very difficult. The 62-yr-old proband presented with duodenal adenocarcinoma. His history of subtotal colectomy for colon cancer, the rarity of duodenal adenocarcinoma in the general population, and his family history of colon cancer made us suspect that he might have FAP. We investigated this family by obtaining medical records and performing gene analysis. The proband had only 10 adenomatous colon polyps when he underwent subtotal colectomy for the cancer, so classic FAP was excluded. His family history included rectal cancer in his brother at 69 yr of age, colon cancer in his mother at 75 yr, and colon cancer in one maternal cousin at 42 yr. Three months after we started to study this family, the proband's 32-yr-old son presented with rectal cancer. His family fulfilled the Amsterdam criteria for HNPCC, but AFAP could not be excluded. Upon gene testing, the proband was negative for APC gene germline mutation, which made AFAP highly unlikely. Moreover, high microsatellite instability (MSI) was detected in his adenomas and cancer tissues. The fulfillment of Amsterdam criteria, the exclusion of FAP and AFAP, and the high MSI established the diagnosis of HNPCC in this family. We also summarize the differences between FAP, AFAP, and HNPCC; extend the graphic description of the MSI mechanism; and propose a diagnostic strategy for HNPCC.
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PMID:Challenge in the differentiation between attenuated familial adenomatous polyposis and hereditary nonpolyposis colorectal cancer: case report with review of the literature. 1213 43

Desmoid tumours (DT) are slow-growing tumours that consist of proliferations of well-differentiated fibroblasts. Although the typical characteristics of malignant tumours, such as distant metastases, are absent, the tumours are locally aggressive and grow into neighbouring structures. The prevalence of desmoid tumours in patients with FAP is 7-12%. The lifetime risk of developing desmoid tumours is about 20%. In FAP, most tumours are intra-abdominal or located in the abdominal wall. Next to colorectal cancer, desmoid tumours are the most frequent cause of death in FAP. Possible risk factors for the development of desmoid tumours are previous surgical procedures, pregnancy, female sex, a family history of desmoid tumours, and specific mutations in the APC-gene. Both CT scanning and MRI can be used to detect the tumours. An excision biopsy is needed to establish the diagnosis. Medicinal treatment with NSAIDs is the treatment of first choice, followed by hormonal treatment (e.g., tamoxifen) in combination with NSAIDs. Both forms of treatment lead to a response in about 30-50% of the patients. Surgery is the preferred treatment for extra-abdominal tumours or tumours located in the abdominal wall. Surgical treatment of intra-abdominal tumours is only indicated in patients with obstruction of the bowel or ureter. Chemotherapy is indicated in patients with progressive desmoid tumours when non-cytotoxic treatment has failed. Radiotherapy may play a role in the treatment of irresectable extra-abdominal or abdominal wall tumours, or as adjuvant treatment of tumours with positive margins.
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PMID:[Desmoid tumors in patients with familial adenomatous polyposis]. 1216 72

We have recently demonstrated that inherited defects of the base excision repair gene MYH predispose to multiple colorectal adenomas and carcinoma. Three affected siblings from a single British family were identified as Y165C/G382D compound heterozygotes and both missense mutations were shown to be functionally compromised. Here, we report the identification of seven further unrelated patients with >100 colorectal adenomas (six with colorectal cancer) and biallelic germline mutations in MYH: four were homozygous for truncating mutations, two were homozygous for Y165C and one was a Y165C/G382D compound heterozygote. As predicted from studies of the bacterial and yeast orthologues of MYH, colorectal tumours from affected individuals displayed a significant excess of somatic G:C-->T:A mutations in APC, as compared to sporadic ( chi(2)=242.96, P<10(-20)) or FAP-associated ( chi(2)=194.85, P<10(-20)) colorectal tumours. The sequence immediately downstream of the somatic G:C-->T:A mutations was predominantly AA, irrespective of the nature of the germline MYH mutations. These findings confirm the role of MYH in colorectal adenoma and carcinoma predisposition.
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PMID:Biallelic germline mutations in MYH predispose to multiple colorectal adenoma and somatic G:C-->T:A mutations. 1239 7

Biallelic germline mutations in the base excision repair gene MYH have been reported in patients with multiple colorectal adenomas and cancer and in sporadic FAP patients not showing a detectable APC germline mutation. In this study, the prevalence of the common Y165C and G382D germline variants of the MYH gene was examined in 70 FAP/AAPC patients with no detectable APC mutation and a family history compatible with recessive inheritance. In addition, 141 normal-population adenoma patients (mean number of adenomas, 2.8; range, 1-9) and 52 clean colon controls were studied. The entire coding region of the MYH gene was analyzed in Y165C or G382D heterozygous patients. Since the same second mutational event (a 3 bp deletion in exon 14, 1395delGGA) was detected in 3 patients, the prevalence of this variant was also examined in all groups. In all, 14 of 70 patients in the FAP/AAPC group (20%; 95% CI = 11.7-31.6%) had biallelic germline MYH variants and 3 were heterozygotes (4.3%). None of the 141 normal-population adenoma patients carried biallelic germline MYH variants (95% CI = 0.06-4.1%) and 3 were heterozygotes (2.1%). In the control group, no MYH variants were detected. These results indicated that MYH-associated polyposis (MAP) is present in about 20% of Italian FAP/AAPC patients, in whom no germline APC mutation is detectable and showing a family history compatible with recessive inheritance, and in a small fraction of patients with colorectal adenomas in the general population. In addition, our data suggest that mutation 1395delGGA is a subpolymorphic MYH mutational event in some Caucasian populations.
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PMID:Prevalence of the Y165C, G382D and 1395delGGA germline mutations of the MYH gene in Italian patients with adenomatous polyposis coli and colorectal adenomas. 1499 74

The MYH gene has recently been shown to be associated with a recessive form of colorectal adenomatous polyposis. Two common mutations in the MYH gene have been identified that lend themselves to rapid screening. We have examined a series of 302 individuals comprising 120 control subjects, 120 patients diagnosed with adenomatous polyposis but without germline mutations in the APC gene and 62 patients diagnosed with familial adenomatous polyposis all harbouring confirmed causative APC germline mutations. The results reveal that MYH accounts for 16 percent of polyposis patients without germline mutations in the APC gene and that it does not appear to be a modifier gene in FAP patients diagnosed with APC germline mutations.
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PMID:Mutation analysis of the MYH gene in an Australian series of colorectal polyposis patients with or without germline APC mutations. 1576 60

HNPCC and FAP are inherited diseases with a lifetime risk of colorectal cancer (CRC) of 80-100% in gene carriers. Disease-causing mutations have been identified in the APC gene at FAP and in MMR genes at HNPCC. In FAP-patients, screening has reduced the prevalence of CRC by 55%, and the survival rate has improved considerably. For HNPCC-patients, 77% of CRCs found by screening were Duke' A or B, and survival after CRC has improved significantly since 1990. Continuous central registration in the HNPCC and Polyposis registers is recommended to ensure identification of high-risk families and evaluate the effect of screening.
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PMID:[Hereditary colorectal cancer]. 1626 67

The authors present a case of FAP, familial adenomatous polyposis. This condition comprises 3 different syndromes characterized by the development of numerous polyps in the colon. Other different expressions of the same genetic anomaly are: familial adenomatous polyposis coli, Gardner's syndrome and Turcot's syndrome. The main risk for these pathologies consists in the frequent cancer outcome, which usually occurs between the 4th and the 5th decade of life and, however, after about 12 years from the first diagnosis. The patient came to the authors' observation in the surgery room of the department of geriatrics, in the university of Catania, where patients from South Italy and Sicily are treated. He had a severe anemic condition and poor general health. At the time of the diagnosis the patient, 56 years old, was subjected to endoscopic investigations which showed extensive polyposis of the entire colon and of the stomach, later on typified as ''Familial polyposis''. He was then subjected to total colectomy and gastric polypectomy. Besides, the patient and his direct family members (4 children and 2 sisters) were also genetically screened. The results proved that the patient and 3 of his children presented a genetic mutation located in connection with one of the two alleles of the APC gene. The potentially cancerous evolution makes it necessary to perform a genetic screening of all direct relatives of patients affected by FAP in order to both uncover the genetic anomaly responsible for this pathology and to prevent cancer, which is the natural outcome of this disease.
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PMID:About a case of familial adenomatous polyposis. 1649 38

Some of the APC negative FAP and AFAP cases have recently been found to be attributable to MYH associated polyposis (MAP). MAP is an autosomal recessive syndrome associated with 5-100 colorectal adenomas and caused by mutation in the MYH gene. Here, we screened for germline MYH mutations in 82 APC-mutation-negative probands with classical and attenuated familial adenomatous polyposis using the denaturing high performance liquid chromatography (DHPLC) method in combination with sequencing. Altogether 12 previously reported changes and four novel genetic alterations, mostly in intronic sequences, were identified. The results revealed the presence of biallelic germline MYH mutations in two patients. These patients were compound heterozygotes for two of the most common germline mutations c.494 A>G (p.Y165C); c.1,145 G>A (p.G382D). These variants are established to be associated with adenomatous polyposis and colorectal cancer. No novel pathogenic mutation has been identified in our study.
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PMID:Mutation analysis of the MYH gene in unrelated Czech APC mutation-negative polyposis patients. 1752 38

A large proportion of non-FAP non-HNPCC patients with multiple colorectal adenomas have been reported to carry germline mutations on the MYH gene. 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. Four hundred fifty-three APC-negative patients with more than five colorectal adenomas were screened for mutations on the entire coding sequence of the MYH gene. Pathogenic mutations were initially found in 74 patients without extradigestive tumors (22.5%) and subsequently in 75 at-risk relatives. Polyposis was more severe in cases with biallelic mutations. However, mutation copy number was correlated neither with the age at diagnosis of adenomas or adenocarcinomas, nor with the presence of a family history of colorectal tumors. 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. MYH-associated polyposis is a frequent inherited colorectal cancer predisposition with a strong dominance component. From age 25-30, MYH mutation carriers should be proposed an early screening program, which includes endoscopies of the upper digestive tract and the colorectum every 2 years.
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PMID:Similar colorectal cancer risk in patients with monoallelic and biallelic mutations in the MYH gene identified in a population with adenomatous polyposis. 1794 94

Hereditary forms of colorectal cancer, as is the case with virtually all forms of hereditary cancer, show extensive phenotypic and genotypic heterogeneity, a phenomenon discussed throughout this special issue of Familial Cancer. Clearly, the family physician, oncology specialist, genetic counselor, and cancer geneticist must know fully the complexity of hereditary cancer syndromes, their differential diagnosis, in order to establish a diagnosis, direct highly-targeted surveillance and management, and then be able to communicate effectively with the molecular geneticist so that an at-risk patient's DNA can be tested in accord with the syndrome of concern. Thus, a family with features of the Lynch syndrome will merit microsatellite instability testing, consideration for immunohistochemistry evaluation, and mismatch repair gene testing, while, in contrast, a patient with FAP will require APC testing. However, other germline mutations, yet to be identified, may be important should testing for these mutations prove to be absent and, therein, unrewarding to the patient. Nevertheless, our position is that if the patient's family history is consistent with one of these syndromes, but a mutation is not found in the family, we still recommend the same surveillance and management strategies for patients from families with an established cancer-causing germline mutation. Our purpose in this paper is to provide a concise coverage of the major hereditary colorectal cancer syndromes, to discuss genetic counseling, molecular genetic evaluation, highly targeted surveillance and management, so that cancer control can be maximized for these high hereditary cancer risk patients.
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PMID:Hereditary colorectal cancer syndromes: molecular genetics, genetic counseling, diagnosis and management. 1799 61


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