Genética do câncer colorretal

Colorectal cancer (CRC) is one of the most important neoplasms not only for its prevalence but also for its incidence, accounting for 10% of all the neoplasms in the USA. However, its mortality remained unaffected in the last 50 years. Since Morson described the adenoma-carcinoma sequence for the first time in 1978, the elucidation of the molecular mechanisms involved in the pathogenesis of CRC became intensively studied and many progresses were obtained. Several genes, like APC, DCC and p53, among others, were identified as participants of the adenoma-carcinoma sequence. They are involved in the multi-step process of the tumorigenesis, where the accumulation of genetic mutations in unstable cells represents the most important factor, which ends up rising the cancer. There are two basic types of CRC : the sporadic, that accounts for 85% of the total of cases of CRC ; and the familal, with about 15 % of the cases, which includes the Adenomatous Polyposi of the Colum (APC) and the Hereditary Non-Polyposis Colorectal Câncer (HNPCC). The mechanisms of action of such genes are now being described and research is being made to determine their prognostic value. One expect that the complete elucidation of such mechanisms will allow a decrease not only on the mortality, but also on the social impact imposed by such disease. Moreover, altemative treatments for surgery seems possible by gene therapy. Therefore, it is imperative for gastrointestinal surgeons and physicians to be familiarized with the genetics of the colorectal cancer.O câncer colorretal (CCR) é uma das neoplasias de maior importância atualmente, tanto por sua prevalência como por sua incidência, correspondendo a 10% de todas as neoplasias nos EUA. Contudo, nos últimos 50 anos, sua mortalidade permaneceu praticamente inalterada. Desde que Morson, em 1978, descreveu pela primeira vez a seqüênciaadenoma-carcinoma, a elucidação da genética molecular envolvida na patogênese do CCR passou a ser estudada intensamente e muitos avanços foram obtidos. Vários genes como APC, DCC e p53, entre outros, foram identificados como participantes da seqüência adenoma-carcinoma, estando envolvidos na gênese tumoral baseada na teoria de múltiplos passos, onde o acúmulo de mutações genéticas em células instáveis é o fator principal que acaba por originar o câncer. Há dois tipos básicos de CCR: o esporádico, que corresponde a 85% do total de casos de CCR; e o familiar, com cerca de 15% dos casos e destaque para a Polipose Adenomatosa Familiar (PAF) e o Câncer Colorretal Hereditário não-poliposo (HNPCC). As pesquisas atuais vêm decifrando o mecanismo de ação de tais genes, buscando determinar a importância e valor prognóstico dos mesmos. Espera-se que a elucidação completa de tais mecanismos permita uma diminuição não só da mortalidade do CCR, mas também do impacto social imposto por tal doença. Ademais, a elaboraçãode tratamentos alternativos à cirurgia parece possível, através da terapia genética. Portanto, familiarizar-se com a Genética do Câncer Colorretal e os avanços nessa área torna-se imperativo para clínicos e cirurgiões da área digestiva

Diagnóstico e manejo do câncer gástrico familiar

Embora a neoplasia gástrica maligna constitua-se numa das principais causas de mortalidade por câncer, as bases moleculares desta enfermidade permanecem ainda pouco compreendidas. Recentemente, a identificação de lesões gástricas difusas ocorrendo em famílias com padrão de transmissão tipicamente mendeliano, resultou no achado de um evento molecular único: mutações no gene da caderina-E. Esta entidade foi denominada câncer gástrico hereditário. Apesar de rara, a sua identificação deve ser suspeitada na prática clínica, já que é possível detectar-se casos precoces de câncer nestas famílias em alto risco. Como a análise mutacional do gene da caderina-E só é realizada em pouquíssimos centros no mundo, é importante tentar identificar estas famílias por meio de critérios de fácil acesso para qualquer profissional de saúde. Este trabalho comenta os critérios sugeridos pelo International Gastric Cancer Linkage Consortium (IGCLC), propostos em 1999, além de tentar estabelecer algumas diretrizes para o rastreamento das pessoas em risco

Initial experience with stapled hemorrhoidopexy for treatment of hemorrhoids

BACKGROUND: Introduction of stapled hemorrhoidopexy by Longo in 1998 represented a radical change in the treatment of hemorrhoids. By avoiding multiple excisions and suture lines in the perianal region, stapled hemorrhoidopexy is intended to offer less postoperative pain than with conventional techniques. OBJECTIVE: To report and analyze the intra and postoperative results gained during initial experience with stapled hemorrhoidopexy. METHODS: One hundred and fifty five patients (67 males) with average age of 39.5 years (21-67 years) underwent stapled hemorrhoidopexy between June 2000 and December 2003 with symptomatic third-degree (n = 74) and fourth-degree (n = 81) hemorrhoids. Mean follow-up period was 20 months (14-60 months). RESULTS: Preoperative symptoms were prolapse (96.7%) and anal bleeding (96.1%). Overall mean operative time was 23 minutes (16-48 minutes). We observed one case of stapler failure and one case of failure to introduce the stapler occurred in a patient with previous anal surgery. Additional sutures for hemostasis were required in 103 patients (66.5%). Resection of skin tags was performed in 45 cases (29%). Postoperatively scheduled analgesia with oral dipyrone and celecoxib was enough for pain control in 131 patients (84.5%). Rescue analgesia was necessary in 24 cases (15.5%). Five patients needed opiates for pain control. Hospital discharge took place on the first postoperative day in 140 patients (90.3%). First defecation without pain was reported by 118 patients (76.1%). Postoperative complications were anal bleeding (10.3%), severe pain (3.2%), urinary retention (3.9%), fever without any signs of perianal infection (1.9%), incontinence for flatus (1.9%), hemorrhoidal thrombosis (1.3%). Two patients presented symptoms of recurrent hemorrhoidal disease and were successfully treated by conventional hemorrhoidectomy. They were no cases of anal stenosis, permanent incontinence, chronic pain or deaths in this series. CONCLUSIONS: Hemorrhoidopexy can be considered a feasible and safe alternative technique to conventional hemorroidectomy for select patients