Expressão antigênica em carcinomas do plexo coróide humano: relato de dois casos

Abstract

Primary neoplasms of choroid plexus are rare. Six morphological variants have been described: papillary, cystic, acinar, mucus-secreting, oncocytic, and anaplastic. The anaplastic variant, the so-called choroid plexus carcinoma, is the rarest of all and can metastasize. The differential diagnosis of the anaplastic variant of choroid plexus neoplasms with adenocarcinomas, melanomas and undifferentiated neoplasms can be troublesome chiefly in adults. The now large use of immunocytochemical techniques in tissue section has become a powerful tool in the analysis of cell lineages, tumoral and non-tumoral. Nevertheless, the choroid plexus neoplasms have shown a complex and a somewhat confusing pattern of antigenic expression. In two choroid plexus carcinomas (one localized in the right lateral ventricle from a boy of 1 year and 9 months old, and the other localized in the left lateral ventricle from a girl of 3 years old) the following antigens were searched (using the avidin-biotin-peroxidase complex): glial fibrillary acidic protein (GFAP) with monoclonal and polyclonal antibodies; cytokeratins of 40-50kDa, cytokeratins of 60-70kDA (callus cytokeratin), neuronal specific enolase (NSE) and S-100 protein with monoclonal antibodies. The two neoplasms showed immunoreactivity against NSE, S-100 protein and cytokeratin of 40-50kDA. The neoplasm of the boy exhibited glial differentiation having immunoreactivity against GFAP with monoclonal and polyclonal antibodies.

Carcinoma de plexo coróide: relato de quinze casos

“…A análise imuno-histoquímica dos CPC continua sendo objeto de estudo, devido à sua relativa falta de especificidade e sensibilidade. Em diferentes estudos, a positividade para CK varia de 83-100%, para a S-100 de 40-94%, para VIM de 16-88%, para a EMA de 69-71%, para a GFAP de 22-85% e para a ENE de 20-100% 2,[8][9][10][11]16,17 . A negatividade para o CEA é útil na diferenciação com os adenocarcinomas metastáticos, embora alguns estudos relatem uma positividade em até 50% dos casos dos CPC 2,9 .…”

“…Em adultos, como um de nossos casos, adenocarcinomas metastáticos e melanomas devem ser excluídos, antes de se firmar o diagnóstico de CPC 11 .…”

“…Até a presente data, somente uma grande série (sete casos) foi publicada há mais de 10 anos na literatura latino-americana 10 , além de esparsos relatos isolados 5,11,12 .…”