Broad phenotypic spectrum in familial adenomatous polyposis; from early onset and severe phenotypes to late onset of attenuated polyposis with the first manifestation at age 72

<p>Abstract</p> <p>Background</p> <p>Familial adenomatous polyposis (FAP) is typically characterized by multiple colonic polyps and frequent extracolonic features. Whereas the number of colonic polyps has been linked to the <it>APC </it>gene mutation, possible genotype-phenotype correlations largely remain to be defined for the extracolonic manifestations.</p> <p>Methods</p> <p>Full genomic sequencing combined with multiplex ligation-dependent probe amplification was used to identify <it>APC </it>gene mutations, which were correlated to the clinical presentations.</p> <p>Results</p> <p>10 novel <it>APC </it>gene mutations were identified in 11 families. A broad spectrum of extracolonic manifestations was identified in most of these individuals. Two sisters with an insertion in codon 528 (c.1582_1583insGC) both showed severe phenotypes with classical polyposis, upper gastrointestinal polyps and thyroid cancer. A woman with a 3'<it>APC </it>mutation (c.5030_5031insAA) developed colon cancer at age 72 as the first manifestation of attenuated FAP.</p> <p>Conclusion</p> <p>With an increasing number of FAP families diagnosed, a broad and variable tumor spectrum and a high frequency of extracolonic manifestations are gradually recognized. We report novel <it>APC </it>mutations and present two FAP cases that suggest familial aggregation of thyroid cancer and demonstrate the need to consider attenuated FAP also among elderly patients with colon cancer.</p

Polipose múltipla familiar: análise de 44 casos tratados no Hospital das Clínicas da FMRP-USP Familiar adenomatosis polyposis: analysis of forty-four cases from the school of medicine of Riberão preto Hospital and Clinics

Os autores apresentam análise retrospectiva de 44 pacientes com Polipose Múltipla Familiar tratados no Hospital das Clínicas da Faculdade de Medicina de Ribeirão Preto,Universidade de São Paulo, entre janeiro de 1991 a julho de 2005. Foram estudados aspectos epidemiológicos (idade, sexo), genéticos, principais sintomas, antecedentes pessoais e aspectos envolvendo tratamento cirúrgico e complicações pós-operatórias, comparando os achados com os da literatura correlata. Dos pacientes, 31 são do sexo masculino e 13 do feminino com idade média de 32 anos (14 - 60 anos). Os sintomas prevalentes foram: sangramento intestinal (62,5 %), alteração do hábito intestinal (60%), e com menor freqüência dor abdominal (45 %) e emagrecimento (30%). Relataram casos de polipose familiar 67,5% dos pacientes e 62,5% referiram parentes com antecedente de neoplasias (intestinal e extra-intestinal). Cerca de 32,5% dos pacientes já apresentavam neoplasia de cólon na época do diagnóstico da polipose,com idade média de 39 anos. O tratamento cirúrgico foi realizado em 95,4% dos pacientes: 35,7% foram submetidos à proctocolectomia total(9 casos com bolsa ileal em J e 6 casos com ileostomia definitiva) e 59,2% a colectomia total com ileorretoanastomose. Atualmente 57% dos pacientes avaliados ainda estão em seguimento com reavaliações periódicas, 7% faleceram e 27% abandonaram o tratamento.<br>The authors present a retrospective analysis of forty-four patients with familiar adenomatosis polyposis treated at the School of Medicine of Ribeirão Preto Hospital and Clinics - University of São Paulo, from January 1991 to July 2005. Epidemiologic (age and gender) and genetic aspects were investigated as well as main symptoms, personal history and surgical treatment outcome. Data obtained were compared to the available literature. Our results show that 31 patients were male and 13 female, with average age of 32 years-old (14 to 60 years-old). The main symptoms were intestinal bleeding (62.5 %) and intestinal habit alteration (60 %). Less frequently, patients showed abdominal pain (45 %) and loss of weight (30 %). Familiar adenomatosis polyposis was reported by 67.5 % of the patients and relatives with neoplasms (intestinal and extra-intestinal) were referred by 62.5 % of the patients. By the time of the polyposis diagnosis, 32.5 % of the patients have already been diagnosed for colon cancer, with average age of 39 years old. Surgical treatment was performed in 95.4 % of the patients, total proctocolectomy was performed in 35.7 % (9 cases with ileal J- pouch and 6 with permanent ileostomy) and total colectomy with ileo rectal anasthomosis in 59.2%. From all patients evaluated, 57 % are still under follow up, 7 % died and 27 % gave up treatment