Tumores de estroma gastrointestinal / Gastrointestinal stromal tumors

Objetivos: Nos últimos anos foram desenvolvidos diversos trabalhos visando entender o comportamento biológico e definir a melhor forma de abordagem para os Tumores de Estroma Gastrointestinal. Nessa revisão, são organizadas informações atualizadas sobre o assunto. Métodos: Foi realizado levantamento bibliográfico, sem restrição de período, nas bases de dados PubMed e LILACS. Foi utilizada a palavra- -chave "Tumores de Estroma Gastrointestinal", que deveria aparecer no título dos artigos. Foram encontrados 1619 artigos e, depois da leitura dos resumos, foram selecionados 20 artigos publicados entre 1998 e 2018. Resultados: Foram levantados dados relevantes e atualizados sobre a epidemiologia, histopatologia, apresentação clínica, diagnóstico, prognóstico e tratamento dos Tumores de Estroma Gastrointestinal. Conclusões: Apesar de ser considerada uma neoplasia rara, é um assunto que deve ser estudado e discutido pela definição recente do diagnóstico e da abordagem terapêutica.

Objectives: In recent years, several studies have been developed to understand the biological behavior and to define the best therapeutic approach for Gastrointestinal Stromal Tumor. In this review, we have organized up-to-date information on the subject. Methods: A bibliographic survey was carried out, without period restriction, in PubMed and LILACS databases. The key word "Gastrointestinal Stromal Tumors" was used, which should appear in the title of the articles. A total of 1619 articles were found and, after reading the abstracts, 20 papers published between 1998 and 2018 were selected. Results: We collected relevant and updated data on the epidemiology, histopathology, clinical presentation, diagnosis, prognosis and treatment of Gastrointestinal Stromal Tumors. Conclusions: Despite being considered a rare neoplasm, it is a subject that must be studied and discussed because of the recent definition of diagnosis and the therapeutic approach.

Polymerase chain reaction (PCR) as a laboratory tool for the evaluation of the parasitological cure in Chagas disease after specific treatment

The evaluation of the treatment for chronic Chagas disease faces the absence of any clear-cut criterion of cure. The low degree of parasitemia and the persistence of positive immunologic reactions represent some of the difficulties involved in addressing therapeutic efficacy. Our aim was to define whether PCR could be used as a laboratory method for evaluating cure in Chagas disease after specific treatment. We tested the utility of PCR amplification of the variable regions of minicircles from Trypanosoma cruzi kinetoplast DNA, in 76 xenopositive chronic Brazilian patients who been treated with benznidazole in Mambai (Goias State) and São Felipe (Bahia State). We observed a positive amplification result in only 25 out 76 treated patients (33 per cent). Therefore, the performance of one single PCR after therapy revealed parasite clearance in 67 per cent of the treated individuals, while xenodiagnosis was negative in 84 per cent. These observations suggest that PCR is the most sensitive technique available for directed detection of T. cruzi in chagasic patients and that it can be a very useful instrument for the follow-up of patients after specific chemotherapy. In this sense, we are now developing a quatitative approach based on the use of fluorogenic probes and reat-time measurements of the amplification reaction (TacMan Technology) in order to precisely estimate the parasite load in chronic chagasic patients before and after treatment. This may be the basis for the futuer establishment of reliable criteria of cure for patients undergoing therapy.