RESUMO
BACKGROUND: Gastrointestinal polyposis syndromes are the second most common cause of hereditary colorectal carcinomas after Lynch syndrome (hereditary non-polyposis colon cancer, HNPCC). The detection of a causal germline mutation in an affected family member serves for differential diagnosis, assessment of the recurrence risk and predictive testing of healthy individuals at risk. OBJECTIVES: The present article aims to provide an overview of the differential diagnosis of different gastrointestinal polyposis syndromes based on the endoscopic findings, polyp histology, extraintestinal phenotype and molecular genetic diagnostics. MATERIALS AND METHODS: The present article is based on a literature search on gastrointestinal polyposis syndromes. RESULTS: In addition to familial adenomatous polyposis (FAP), there are further subtypes of adenomatous polyposis that can often only be distinguished by the detection of a causative germline mutation and are sometimes associated with different extracolonic manifestations. In hamartomatous polyposis syndromes, the clinical overlaps often cause differential diagnostic problems. Serratated polyposis syndrome is possibly the most frequent polyposis syndrome, although its cause is currently largely unexplained. CONCLUSIONS: Early detection and correct classification of polyposis is crucial for adequate prevention and therapy. Access to multidisciplinary expert centres is useful for the care of families.
Assuntos
Polipose Adenomatosa do Colo/diagnóstico , Polipose Adenomatosa do Colo/genética , Neoplasias Colorretais/diagnóstico , Neoplasias Colorretais/genética , Detecção Precoce de Câncer/métodos , Humanos , Fenótipo , SíndromeRESUMO
The present article summarises the relevant aspects of the S3 guidelines on endometrioid carcinomas. The recommendations include the processing rules of fractional currettings as well as for hysterectomy specimens and lymph node resections (including sentinel lymph nodes). Besides practical aspects, the guidelines consider the needs of the clinicians for appropriate surgical and radiotherapeutic treatment of the patients. Carcinosarcomas are assigned to the endometrial carcinoma as a special variant. For the first time, an algorithmic approach for evaluation of the tumour tissue for Lynch syndrome is given. Prognostic factors based on morphologic findings are summarised.
Assuntos
Carcinoma Endometrioide , Neoplasias do Endométrio , Endométrio , Feminino , Humanos , Excisão de LinfonodoRESUMO
BACKGROUND AND AIM: MUTYH-associated polyposis (MAP) is an autosomal recessive inherited disorder characterised by the development of polyposis in the upper and lower gastrointestinal tract and a high risk of colorectal cancer (CRC). We evaluated the natural history of the disease and the outcome of colorectal surveillance and management. METHODS: A large Western European dataset of biallelic MUTYH mutation carriers comprising 254 patients was used. Detailed information was collected on polyp and cancer development in the colorectum, and the outcome of surveillance and surgery. Survival methods were used to calculate the risk of CRC development. RESULTS: The mean follow-up was 9.8 years. Colorectal polyposis was diagnosed at a mean age of 44.8 years (range: 12-77 years). Most patients had <100 colorectal adenomas at diagnosis. CRC was diagnosed in 147 (58%) of the 254 patients (mean age at diagnosis: 48.5, range: 21-77 years). The cumulative lifetime risk of CRC was 63% at age 60 years. There was no correlation between the number of adenomas and the presence of CRC. The cumulative risk of CRC in patients presenting with polyps was 9% after 5 years of follow-up. Patients presenting with CRC had 11% risk of developing a metachronous CRC at 5 years after surgery. Thirty-seven per cent of patients with MAP with CRC who underwent partial colonic resection needed secondary surgery shortly afterwards. CONCLUSIONS: The high risk of developing CRC under surveillance in patients with MAP may suggest an accelerated carcinogenesis. Surveillance of these patients should therefore include colonoscopy at short intervals, for example, at 1-2-year intervals starting from the age of 18 to 20 years. If surgery for CRC is warranted, a (sub)total colectomy is recommended.
Assuntos
Adenoma/patologia , Neoplasias Colorretais/patologia , DNA Glicosilases/genética , Progressão da Doença , Polipose Intestinal/patologia , Adenoma/genética , Adenoma/cirurgia , Adolescente , Adulto , Idoso , Criança , Colectomia , Neoplasias Colorretais/genética , Neoplasias Colorretais/cirurgia , Feminino , Seguimentos , Marcadores Genéticos , Mutação em Linhagem Germinativa , Humanos , Polipose Intestinal/genética , Polipose Intestinal/cirurgia , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Vigilância da População , Reoperação , Resultado do Tratamento , Adulto JovemRESUMO
AIM: Patients with germline phosphatase and tensin homologue (PTEN) mutations develop hamartomatous lesions in several organs and are at increased risk of various malignancies. We assessed the lifetime risk of benign and malignant gastrointestinal lesions in patients with a proven PTEN mutation. METHOD: Data on gender, mutation, dates of birth, last contact, and diagnosis, location and type of gastrointestinal lesions were collected from nine countries. The lifetime risk of gastrointestinal lesions was calculated by Kaplan-Meier methods. RESULTS: A total of 156 patients (67 men, 43%) from 101 families with a PTEN mutation were included. Patients were born between 1928 and 2008. Benign gastrointestinal polyps were reported in 49 (31%) patients at a mean age of 38 years (range 18-62 years) and were most often hamartomas. Twenty-two (44%) patients had upper as well as lower gastrointestinal lesions, 14 (29%) had only colonic lesions and 13 (27%) had gastrointestinal lesions at unknown sites. The cumulative risk of developing benign gastrointestinal polyps was 70% at age 60. Four patients (two men) developed colorectal carcinoma at 53, 57, 59 and 62 years, respectively. The cumulative risk of developing colorectal carcinoma was 18% at age 60. Except for one carcinoid in the small intestine, no upper gastrointestinal cancers were observed. CONCLUSION: Benign gastrointestinal lesions are common in PTEN mutation carriers, and a three- to four-fold increased lifetime risk of colorectal cancer compared with the general population may exist. Colorectal screening of patients with germline PTEN mutations is recommended, starting at age 40 years.
Assuntos
Pólipos do Colo/genética , Neoplasias Colorretais/genética , Síndrome do Hamartoma Múltiplo/genética , PTEN Fosfo-Hidrolase/genética , Adolescente , Adulto , Idoso , Criança , Pré-Escolar , Estudos de Coortes , Pólipos do Colo/etiologia , Neoplasias Colorretais/etiologia , Feminino , Predisposição Genética para Doença , Mutação em Linhagem Germinativa , Síndrome do Hamartoma Múltiplo/complicações , Humanos , Lactente , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-IdadeRESUMO
Hereditary gastrointestinal polyposis syndromes account for around 1% of all colorectal cancers; most of them are associated with a broad spectrum of extracolonic tumors. The initial diagnosis is based on endoscopic findings and polyp histology. Molecular genetic screening is important for the delineation of conditions with a similar phenotype such as autosomal dominant familial adenomatous polyposis (FAP) and autosomal recessive MUTYH-associated polyposis (MAP). Identification of the germline mutation in an affected person is a prerequisite for the exact evaluation of the recurrence risk in relatives and the predictive testing of asymptomatic persons at risk. Beside cases with attenuated adenomatosis or few colorectal adenomas, diagnostic difficulties are common among the hamartomatous polyposes such as the juvenile polyposis syndrome due to their broad clinical overlap and uncertainties in histological assessment. Several poorly defined nonhereditary polyposis syndromes and those with an as yet unknown etiology exist including hyperplastic polyposis syndrome. Early detection and accurate classification are essential since effective methods for surveillance and treatment are available.
Assuntos
Polipose Adenomatosa do Colo/diagnóstico , Polipose Adenomatosa do Colo/genética , Detecção Precoce de Câncer/métodos , Testes Genéticos/métodos , HumanosRESUMO
Peutz-Jeghers syndrome (PJS, MIM175200) is an autosomal dominant condition defined by the development of characteristic polyps throughout the gastrointestinal tract and mucocutaneous pigmentation. The majority of patients that meet the clinical diagnostic criteria have a causative mutation in the STK11 gene, which is located at 19p13.3. The cancer risks in this condition are substantial, particularly for breast and gastrointestinal cancer, although ascertainment and publication bias may have led to overestimates in some publications. Current surveillance protocols are controversial and not evidence-based, due to the relative rarity of the condition. Initially, endoscopies are more likely to be done to detect polyps that may be a risk for future intussusception or obstruction rather than cancers, but surveillance for the various cancers for which these patients are susceptible is an important part of their later management. This review assesses the current literature on the clinical features and management of the condition, genotype-phenotype studies, and suggested guidelines for surveillance and management of individuals with PJS. The proposed guidelines contained in this article have been produced as a consensus statement on behalf of a group of European experts who met in Mallorca in 2007 and who have produced guidelines on the clinical management of Lynch syndrome and familial adenomatous polyposis.
Assuntos
Síndrome de Peutz-Jeghers/diagnóstico , Adulto , Idoso , Neoplasias da Mama/diagnóstico , Criança , Pré-Escolar , Endoscopia Gastrointestinal , Medicina Baseada em Evidências/métodos , Feminino , Neoplasias Gastrointestinais/diagnóstico , Neoplasias dos Genitais Femininos/diagnóstico , Genótipo , Humanos , Assistência de Longa Duração/métodos , Masculino , Programas de Rastreamento/métodos , Pessoa de Meia-Idade , Síndrome de Peutz-Jeghers/genética , Síndrome de Peutz-Jeghers/terapia , Fenótipo , Vigilância da População/métodos , Adulto JovemRESUMO
Backround and study aims Duodenal cancer is the cancer most often seen in patients with familial adenomatous polyposis (FAP) who have undergone risk-reducing colonic surgery. Almost all patients with FAP eventually develop duodenal adenomas and risk for duodenal cancer is up to 12â% with poor prognosis. In addition, there is a rising concern regarding increased gastric cancer risk in patients with FAP. Our aim was to enhance polyp detection by using CE (CE) with the application of indigo carmine dye. Patient and methods We conducted a prospective, blinded study of patients with FAP undergoing endoscopic examination of the upper gastrointestinal tract. First, a standard white-light examination (WLE) was done followed by an examination performed by an endoscopist who was blinded to the previous examination, using chromoendoscopy (CE) (0.4â% indigo carmine dye). Results Fifty patients were included in the study. Using WLE, a median number of 13 adenomas (range 0-90) was detected compared to 23 adenomas/patient (range 0-150; P â<â0.0001) detected after staining, leading to a higher Spigelman stage in 16 patients (32â%; P â=â0.0003). CE detected significantly more larger adenomas (>â10âmm) than WLE (12 vs. 19; P â=â0.0391). In the gastric antral region, a median number of 0 adenomas (range 0-6) before and 0.5 adenomas (range 0-7) after staining ( P â=â0.0025) were detected. Conclusion This prospective endoscopic trial, to our knowledge the largest in patients with FAP, showed a significant impact of CE on adenoma detection and therapeutic management in the upper gastrointestinal tract. This leads to more intensive surveillance intervals.
RESUMO
BACKGROUND: Familial adenomatous polyposis (FAP) is a well-described inherited syndrome, which is responsible for <1% of all colorectal cancer (CRC) cases. The syndrome is characterised by the development of hundreds to thousands of adenomas in the colorectum. Almost all patients will develop CRC if they are not identified and treated at an early stage. The syndrome is inherited as an autosomal dominant trait and caused by mutations in the APC gene. Recently, a second gene has been identified that also gives rise to colonic adenomatous polyposis, although the phenotype is less severe than typical FAP. The gene is the MUTYH gene and the inheritance is autosomal recessive. In April 2006 and February 2007, a workshop was organised in Mallorca by European experts on hereditary gastrointestinal cancer aiming to establish guidelines for the clinical management of FAP and to initiate collaborative studies. Thirty-one experts from nine European countries participated in these workshops. Prior to the meeting, various participants examined the most important management issues according to the latest publications. A systematic literature search using Pubmed and reference lists of retrieved articles, and manual searches of relevant articles, was performed. During the workshop, all recommendations were discussed in detail. Because most of the studies that form the basis for the recommendations were descriptive and/or retrospective in nature, many of them were based on expert opinion. The guidelines described herein may be helpful in the appropriate management of FAP families. In order to improve the care of these families further, prospective controlled studies should be undertaken.
Assuntos
Polipose Adenomatosa do Colo/terapia , Polipose Adenomatosa do Colo/diagnóstico , Polipose Adenomatosa do Colo/genética , Idade de Início , Anti-Inflamatórios não Esteroides/uso terapêutico , Neoplasias Duodenais/diagnóstico , Neoplasias Duodenais/terapia , Feminino , Fibromatose Agressiva/diagnóstico , Fibromatose Agressiva/terapia , Genes APC , Predisposição Genética para Doença , Testes Genéticos/métodos , Humanos , Masculino , Fatores de RiscoRESUMO
BACKGROUND: In patients with juvenile polyposis syndrome (JPS) the frequency of large genomic deletions in the SMAD4 and BMPR1A genes was unknown. METHODS: Mutation and phenotype analysis was used in 80 unrelated patients of whom 65 met the clinical criteria for JPS (typical JPS) and 15 were suspected to have JPS. RESULTS: By direct sequencing of the two genes, point mutations were identified in 30 patients (46% of typical JPS). Using MLPA, large genomic deletions were found in 14% of all patients with typical JPS (six deletions in SMAD4 and three deletions in BMPR1A). Mutation analysis of the PTEN gene in the remaining 41 mutation negative cases uncovered a point mutation in two patients (5%). SMAD4 mutation carriers had a significantly higher frequency of gastric polyposis (73%) than did patients with BMPR1A mutations (8%) (p<0.001); all seven cases of gastric cancer occurred in families with SMAD4 mutations. SMAD4 mutation carriers with gastric polyps were significantly older at gastroscopy than those without (p<0.001). In 22% of the 23 unrelated SMAD4 mutation carriers, hereditary hemorrhagic telangiectasia (HHT) was also diagnosed clinically. The documented histologic findings encompassed a wide distribution of different polyp types, comparable with that described in hereditary mixed polyposis syndromes (HMPS). CONCLUSIONS: Screening for large deletions raised the mutation detection rate to 60% in the 65 patients with typical JPS. A strong genotype-phenotype correlation for gastric polyposis, gastric cancer, and HHT was identified, which should have implications for counselling and surveillance. Histopathological results in hamartomatous polyposis syndromes must be critically interpreted.
Assuntos
Receptores de Proteínas Morfogenéticas Ósseas Tipo I/genética , Deleção Cromossômica , Neoplasias Gastrointestinais/genética , Polipose Intestinal/genética , Síndromes Neoplásicas Hereditárias/genética , PTEN Fosfo-Hidrolase/genética , Proteína Smad4/genética , Adolescente , Adulto , Idade de Início , Antígenos CD , Receptores de Proteínas Morfogenéticas Ósseas Tipo I/deficiência , Caderinas/genética , Criança , Pré-Escolar , Análise Mutacional de DNA , Feminino , Neoplasias Gastrointestinais/epidemiologia , Heterogeneidade Genética , Genótipo , Alemanha/epidemiologia , Humanos , Lactente , Polipose Intestinal/epidemiologia , Masculino , Síndromes Neoplásicas Hereditárias/epidemiologia , Técnicas de Amplificação de Ácido Nucleico , PTEN Fosfo-Hidrolase/deficiência , Fenótipo , Mutação Puntual , Proteína Smad4/deficiência , Telangiectasia Hemorrágica Hereditária/epidemiologia , Telangiectasia Hemorrágica Hereditária/genéticaRESUMO
BACKGROUND: Attenuated familial adenomatous polyposis (AFAP) is associated with germline mutations in the 5', 3', and exon 9 of the adenomatous polyposis coli (APC) gene. These mutations probably encode a limited amount of functional APC protein. METHODS AND RESULTS: We found that colonic polyp number varied greatly among AFAP patients but members of the same family tended to have more similar disease severity. 5' Mutants generally had more polyps than other patients. We analysed somatic APC mutations/loss of heterozygosity (LOH) in 235 tumours from 35 patients (16 families) with a variety of AFAP associated germline mutations. In common with two previous studies of individual kindreds, we found biallelic changes ("third hits") in some polyps. We found that the "third hit" probably initiated tumorigenesis. Somatic mutation spectra were similar in 5' and 3' mutant patients, often resembling classical FAP. In exon 9 mutants, in contrast, "third hits" were more common. Most "third hits" left three 20 amino acid repeats (20AARs) on the germline mutant APC allele, with LOH (or proximal somatic mutation) of the wild-type allele; but some polyps had loss of the germline mutant with mutation leaving one 20AAR on the wild-type allele. CONCLUSIONS: We propose that mutations, such as nt4661insA, that leave three 20AARs are preferentially selected in cis with some AFAP mutations because the residual protein function is near optimal for tumorigenesis. Not all AFAP polyps appear to need "three hits" however. AFAP is phenotypically and genetically heterogeneous. In addition to effects of different germline mutations, modifier genes may be acting on the AFAP phenotype, perhaps influencing the quantity of functional protein produced by the germline mutant allele.
Assuntos
Polipose Adenomatosa do Colo/genética , Mutação em Linhagem Germinativa/genética , Proteína da Polipose Adenomatosa do Colo/genética , Adulto , Idoso , Análise Mutacional de DNA , Éxons , Feminino , Humanos , Perda de Heterozigosidade , Masculino , Pessoa de Meia-Idade , Fenótipo , Polimorfismo de Nucleotídeo ÚnicoRESUMO
Sternoclavicular (SC) dislocation is an injury that is very rare in the newborn. Thus far there have been no reports describing this in neonates after a traumatic birth injury. This condition can be difficult to differentiate from epiphyseal separation, which occurs more often in older children. For successful treatment, early diagnosis is essential. Timely surgical reposition and fixation with following immobilization is recommended in instances of complete (SC) dislocation. We report a trauma-induced case of SC dislocation in a neonate successfully managed by polydioxanon cord fixation.
Assuntos
Traumatismos do Nascimento , Luxações Articulares/etiologia , Articulação Esternoclavicular/lesões , Traumatismos do Nascimento/cirurgia , Humanos , Recém-Nascido , Luxações Articulares/cirurgia , Articulação Esternoclavicular/cirurgiaRESUMO
Synovial sarcoma is a high-grade soft tissue malignancy characterized by a specific reciprocal translocation t(X;18), which leads to the fusion of the SS18 (SYT) gene to one of three SSX genes (SSX1, SSX2 or SSX4). The resulting chimeric SS18-SSX protein is suggested to act as an oncogenic transcriptional regulator. Despite multimodal therapeutic approaches, metastatic disease is often lethal and the development of novel targeted therapeutic strategies is required. Several expression-profiling studies identified distinct gene expression signatures, implying a consistent role of Wnt/ß-catenin signaling in synovial sarcoma tumorigenesis. Here we investigate the functional and therapeutic relevance of Wnt/ß-catenin pathway activation in vitro and in vivo. Immunohistochemical analyses of nuclear ß-catenin and Wnt downstream targets revealed activation of canonical Wnt signaling in a significant subset of 30 primary synovial sarcoma specimens. Functional aspects of Wnt signaling including dependence of Tcf/ß-catenin complex activity on the SS18-SSX fusion proteins were analyzed. Efficient SS18-SSX-dependent activation of the Tcf/ß-catenin transcriptional complex was confirmed by TOPflash reporter luciferase assays and immunoblotting. In five human synovial sarcoma cell lines, inhibition of the Tcf/ß-catenin protein-protein interaction significantly blocked the canonical Wnt/ß-catenin signaling cascade, accompanied by the effective downregulation of Wnt targets (AXIN2, CDC25A, c-MYC, DKK1, CyclinD1 and Survivin) and the specific suppression of cell viability associated with the induction of apoptosis. In SYO-1 synovial sarcoma xenografts, administration of small molecule Tcf/ß-catenin complex inhibitors significantly reduced tumor growth, associated with diminished AXIN2 protein levels. In summary, SS18-SSX-induced Wnt/ß-catenin signaling appears to be of crucial biological importance in synovial sarcoma tumorigenesis and progression, representing a potential molecular target for the development of novel therapeutic strategies.
Assuntos
Proteínas de Fusão Oncogênica/fisiologia , Sarcoma Sinovial/metabolismo , Via de Sinalização Wnt , Animais , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Núcleo Celular/metabolismo , Sobrevivência Celular/efeitos dos fármacos , Expressão Gênica , Células HEK293 , Humanos , Masculino , Camundongos Endogâmicos BALB C , Camundongos Nus , Perileno/análogos & derivados , Perileno/farmacologia , Pirimidinonas/farmacologia , Sarcoma Sinovial/tratamento farmacológico , Triazinas/farmacologia , Ensaios Antitumorais Modelo de Xenoenxerto , beta Catenina/genética , beta Catenina/metabolismoRESUMO
We present a case of a 54-year-old woman who was diagnosed with a KRAS positive adenocarcinoma of the lung on the basis of a Peutz-Jeghers syndrome (PJS), which was unknown before. PJS is a rare hereditary disease, which may be associated with the development of poor outcome adenocarcinomas and LKB1-gene mutations. A very rare type of a LKB1 mutation was found, not previously described in lung cancer. Although seldom screened for LKB-1 mutations are found in up to 30% of lung adenocarcinomas and may be druggable therapeutic targets, in particular in KRAS mutant tumours in the near future as recent preclinical results with nucleotides demonstrate.
Assuntos
Adenocarcinoma/complicações , Adenocarcinoma/genética , Neoplasias Pulmonares/complicações , Neoplasias Pulmonares/genética , Síndrome de Peutz-Jeghers/complicações , Proteínas Serina-Treonina Quinases/genética , Proteínas ras/genética , Quinases Proteína-Quinases Ativadas por AMP , Adenocarcinoma/diagnóstico , Adenocarcinoma de Pulmão , Evolução Fatal , Feminino , Humanos , Hiperpigmentação , Lábio/patologia , Pulmão/diagnóstico por imagem , Pulmão/patologia , Neoplasias Pulmonares/diagnóstico , Pessoa de Meia-Idade , Tomografia Computadorizada por Raios XRESUMO
The universal energy source adenosine triphosphate (ATP)is reduced by approximately 30 % in the retinal pigment epithelium (RPE) of elderly persons. Increased oxidative stress and decreased antioxidative capacity, such as glutathione in aging eyes cause impairment of energy-dependent RPE processes and lead to loss of visual function. We developed a cell culture model of aging RPE using atractyloside to inhibit mitochondrial ATP synthesis and tert-butyl hydroperoxide as oxidant. The ATP levels were reduced by 30 % and oxidative damaged proteins and DNA increased whereas antioxidative glutathione decreased. Autophagy as an internal cellular repair mechanism and phagocytosis of photoreceptors were impaired. Antioxidative and mitochondria-activating Ginkgo biloba extract EGb 761 increased the intracellular ATP level and antioxidative glutathione. This cell culture model seems to be suitable to investigate in vitro the effect of protective substances and their compounds on aging processes in RPE.
Assuntos
Trifosfato de Adenosina/metabolismo , Envelhecimento/fisiologia , Metabolismo Energético/fisiologia , Espécies Reativas de Oxigênio/metabolismo , Epitélio Pigmentado da Retina/metabolismo , Células Cultivadas , HumanosRESUMO
Familial colorectal cancer (CRC) accounts for 10-15% of all CRCs. In about 5% of all cases, CRC is associated with a highly penetrant dominant inherited syndrome. The most common inherited form of non-polyposis CRC is the Lynch syndrome which is responsible for about 2-4% of all cases. Surveillance of individuals at high risk for CRC prevents the development of advanced CRC. About 1 million individuals in Western Europe are at risk for Lynch syndrome. We performed a survey to evaluate the strategies currently used to identify individuals at high risk for CRC in 14 Western European countries. Questionnaires were distributed amongst members of a European collaborative group of experts that aims to improve the prognosis of families with hereditary CRC. The survey showed that in all countries obtaining a family history followed by referral to clinical genetics centres of suspected cases was the main strategy to identify familial and hereditary CRC. In five out of seven countries with a (regional or national) CRC population screening program, attention was paid in the program to the detection of familial CRC. In only one country were special campaigns organized to increase the awareness of familial CRC among the general population. In almost all countries, the family history is assessed when a patient visits a general practitioner or hospital. However, the quality of family history taking was felt to be rather poor. Microsatellite instability testing (MSI) or immunohistochemical analysis (IHC) of CRC are usually recommended as tools to select high-risk patients for genetic testing and are performed in most countries in patients suspected of Lynch syndrome. In one country, IHC was recommended in all new cases of CRC. In most countries there are no specific programs on cancer genetics in the teaching curriculum for medical doctors. In conclusion, the outcome of this survey and the discussions within an European expert group may be used to improve the strategies to identify individuals at high risk of CRC. More attention should be given to increasing the awareness of the general population of hereditary CRC. Immunohistochemical analysis or MSI-analysis of all CRCs may be an effective tool for identifying all Lynch syndrome families. The cost-effectiveness of this approach should be further evaluated. All countries with a CRC population screening program should obtain a full family history as part of patient assessment.
Assuntos
Neoplasias Colorretais Hereditárias sem Polipose/diagnóstico , Neoplasias Colorretais/diagnóstico , Neoplasias Colorretais/epidemiologia , Neoplasias Colorretais/genética , Neoplasias Colorretais Hereditárias sem Polipose/epidemiologia , Reparo de Erro de Pareamento de DNA , Europa (Continente)/epidemiologia , Aconselhamento Genético , Predisposição Genética para Doença , Testes Genéticos , Diretrizes para o Planejamento em Saúde , Humanos , Anamnese , Proteína 2 Homóloga a MutS/genética , Mutação , Linhagem , Fatores de RiscoRESUMO
Somatic epimutations in the MLH1 promoter mimic the phenotype of Lynch syndrome. To date, no somatic hypermethylation of the MLH1 promoter in the carrier of a pathogenic MLH1 germline mutation has been identified, prompting the recommendation that a germline mutation in MLH1 should only be sought in the absence of tumour tissue methylation. We aimed to determine whether methylation of the MLH1 promoter may coexist in carriers of a pathogenic germline mutation in MLH1. We examined the methylation status of the MLH1 promoter in 123 tumour tissue samples, demonstrating high microsatellite instability and loss of expression of a mismatch repair protein (60 cases with MLH1 germline mutation, 25 cases without mutation, 38 cases with MSH2 mutations), using combined bisulphite restriction analysis (COBRA) and SNaPshot analysis. Methylation of the MLH1 promoter was found in two patients with pathogenic germline mutations, one a carrier of a MLH1 mutation and the other a carrier of a MSH2 mutation. Our results demonstrate that methylation of the MLH1 promoter region does not exclude the presence of a germline mutation in a mismatch repair (MMR) gene. Hypermethylation of the MLH1 promoter may be present in most cases of sporadic colorectal cancers, but this does not exclude a diagnosis of Lynch syndrome.
Assuntos
Proteínas Adaptadoras de Transdução de Sinal/genética , Neoplasias Colorretais Hereditárias sem Polipose/genética , Mutação em Linhagem Germinativa , Proteínas Nucleares/genética , Regiões Promotoras Genéticas/genética , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Neoplasias Colorretais Hereditárias sem Polipose/metabolismo , Metilação de DNA , Reparo de Erro de Pareamento de DNA , Análise Mutacional de DNA/métodos , DNA de Neoplasias/genética , Humanos , Instabilidade de Microssatélites , Proteína 1 Homóloga a MutL , Proteínas de Neoplasias/genética , Proteínas de Neoplasias/metabolismo , Proteínas Nucleares/metabolismoRESUMO
After the successful sequencing of the human genome the genetic variation between individuals will be worked out in the near future. The genetic differences are the basis for different predispositions to diseases. The next goal is to correlate the host of genetic variants with phenotypes. This endeavor has already been successful for monogenic diseases; however, it will also be possible in genetically complex diseases. If a trait follows a monogenic mode of inheritance, a phenotype results nearly completely from a single mutation; in genetically complex diseases there exists only a statistical relationship. Predictive genetic diagnostics should only be considered after genetic counseling; it makes sense, if there exists efficient prevention or therapy, respectively. This applies e. g. to various familial cancer predispositions. In the future, medical doctors should be able to apply genetic risk figures and to convey them to their patients.
Assuntos
Doenças Genéticas Inatas/diagnóstico , Predisposição Genética para Doença/genética , Técnicas Genéticas/tendências , Aconselhamento Genético/tendências , Doenças Genéticas Inatas/genética , Testes Genéticos/tendências , Variação Genética/genética , Humanos , Neoplasias/genética , Neoplasias/prevenção & controle , Linhagem , Fenótipo , Medição de RiscoRESUMO
HISTORY AND CLINICAL FINDINGS: A 75-year-old man was admitted with increasing dyspnoea and recurrent left-sided chest pain, at first during exercise and later at rest. No cardiovascular risk factors could be found. His past medical history revealed mastectomy and radiotherapy for breast cancer and an operation for benign prostate hyperplasia. At admission the patient was in very poor conditions with marked orthopnoea. Bilateral moist rales were heard over both lungs with a 3/6 diastolic murmur an cardiac auscultation. INVESTIGATIONS: Anterolateral ST segment depression in the ECG and signs of pulmonary oedema in chest X-ray were also noted. Echocardiography discovered global reduced left ventricular contractility with aortic insufficiency (II degree) in mild aortic valve sclerosis. Coronary angiography demonstrated marked dilatation of the coronary arteries without stenosis. The ascending aorta was dilated without angiographic signs of a dissection. DIAGNOSIS, TREATMENT AND COURSE: After medical treatment and a short period without symptoms the patient had to be resuscitated and died after a intense attack of dyspnoea and chest pain. The autopsy revealed a focal dissection of the ascending aorta with a small aortic rupture caused by idiopathic Erdheim's medial necrosis. CONCLUSION: Erdheim's medical necrosis is an important cause of aortic dissection and aortic rupture. If symptoms of acute severe chest pain are present and a coronary syndrome can be excluded, possible disease of the aorta should be investigated. The reported case demonstrates the short time window between onset of symptoms and the necessary treatment.