[Cytogenetic analysis of choroidal melanoma]. / Análisis citogenético del melanoma de coroides.

PURPOSE: To investigate the presence of known cytogenetic alterations of choroidal melanoma in a series of patients diagnosed and treated in our Ocular Oncology Service. A review of the present literature on this topic is also presented. METHODS: Microsatellite analysis (MSA) studies on loss of heterozygosity (LOH) of chromosome 3, as well as multiplex ligation prove amplification (MLPA) on chromosomes 1, 3, 6 and 8, were performed on enucleation or local resection samples obtained from a total of 27 patients, over a 2 year period. RESULTS: Twenty patients showed at least one of the cytogenetic alterations looked for. A total of 11 cases were found that showed LOH of chromosome 3 (44%), 8 gains of chromosome 8 (30%), 8 gains of chromosome 6p (30%), and 7 partial or total losses of chromosome 1 (26%). CONCLUSIONS: This is the first study on the cytogenetics of choroidal melanoma performed in our country. The results are similar to that published in the literature. Cytogenetic analysis provides more accurate knowledge on a vital individual prognosis. It also may become a valuable tool for establishing the most adequate follow-up regimes, and the need for adjuvant therapies.

Estudos sobre a aplicabilidade da citopatologia no diagnóstico precoce do câncer bucal / Studies on the applicability of cytopathology in the early diagnosis of oral cancer

O câncer bucal é uma doença que afeta principalmente homens acima de 40 anos com hábito de fumar e beber. Em geral, esses pacientes têm o diagnóstico da enfermidade realizado tardiamente, acarretando tratamentos complexos, mutilantes e de alto custo tanto financeiro como social e de prognóstico sombrio a ponto do câncer bucal apresentar uma taxa de sobrevida em 5 anos inferior a 50%. O diagnóstico precoce representa uma alternativa importante para alterar esse panorama. Os recursos de que os profissionais da área da saúde, principalmente os cirurgiões-dentistas, dispõem são o diagnóstico clínico de lesões estabelecidas acompanhado da biópsia com exame histopatológico.Outra alternativa para o diagnóstico precoce dos carcinomas espinocelulares ocorre quando estes são precedidos de lesões cancerizáveis. Nas duas últimas décadas, a utilização da citopatologia como método de diagnóstico de danos celulares prévios ao aparecimento de lesões clínicas possibilitou sua utilização em mucosa bucal. Os estudos apresentados tratam especificamente desta aplicação clínica, abordando: a) os aspectos genéticos do câncer bucal; b) a correlação histocitopatológica de lesões cancerizáveis em câncer bucal e na mucosa normal exposta aos carcinógenos; c) a validação das amostras citopatológicas; d) a padronização da técnica de extração de DNA em células esfoliadas da mucosa bucal...

Oral cancer affects mainly men over 40 years who are exposed to tobacco and alcohol. These patients usually receive a late diagnosis, which results in complex, mutilating treatments with high financial and social costs, poor prognosis, and, therefore, a 5-year survival rate lower than 50%. Early diagnosis is critical to change this situation. The resources currently available to healthcare professionals, particularly dentists, are the clinical diagnosis of lesions and biopsies for histopathologic examination. Another alternative for the early diagnosis of squamous cell carcinomas is the identification of precursor lesions. In the last two decades, cytopathology has been used as a method to diagnose cell damage that precedes the appearance of clinical lesions, and this use can be extended to the oral mucosa. The studies reported here deal specifically with this clinical application, and discuss: A) the genetic factors in oral cancer; B) the cytohistologic correlation of cancer precursor lesions and the normal mucosa exposed to carcinogens; C) the validation of cytopathologic samples; D) the standardization of the technique to extract DNA of cells exfoliated from the oral mucosa...