RESUMEN
Primary central nervous system atypical teratoid/rhabdoid tumors mostly occur during early childhood and are almost invariably fatal. These tumors show similar histological and radiological features to primitive neuroectodermal tumor, medulloblastoma and choroid plexus carcinoma, but present different biological behaviors. We present the case of an 18 year-old man who presented headache, vomiting and ataxia. CT-scan and MRI revealed a posterior fossa tumor. A gross total resection was performed. An intraoperative study showed papillary-like tumors with large cells and mitotic features. Histological examination showed two different main growth patterns: solid sheets of undifferentiated polygonal cells with papillary features and rhabdoid cells. Immunohistochemically, these rhabdoid cells were positive for vimentin, epithelial membrane antigen, smooth-muscle actin, cytokeratin, S-100 protein, and glial fibrillary acidic protein. Electro-microscopically, the typical rhabdoid cells contained whorled bundles of intermediate filaments in their cytoplasm. A rhabdoid tumor is a clinical-pathological entity and emphasizes the necessity to distinguish this unique tumor from other pediatric central nervous system neoplasms. Cytopathological features, immunohistochemistry and electro-microscopy differential diagnoses are discussed.
Asunto(s)
Carcinoma/ultraestructura , Neoplasias del Plexo Coroideo/ultraestructura , Tumor Rabdoide/ultraestructura , Adolescente , Carcinoma/diagnóstico por imagen , Carcinoma/cirugía , Neoplasias del Plexo Coroideo/diagnóstico por imagen , Neoplasias del Plexo Coroideo/cirugía , Craneotomía , Humanos , Inmunohistoquímica , Masculino , Tumor Rabdoide/diagnóstico por imagen , Tumor Rabdoide/cirugía , Resultado del Tratamiento , UltrasonografíaRESUMEN
Primary central nervous system atypical teratoid/rhabdoid tumors mostly occur during early childhood and are almost invariably fatal. These tumors show similar histological and radiological features to primitive neuroectodermal tumor, meduloblastoma and choroid plexus carcinoma, but present different biological behaviors. We present the case of an 18 year-old man who presented headache, vomiting and ataxia. CT-scan and MRI revealed a posterior fossa tumor. A gross total resection was performed. An intraoperative study showed papillary-like tumors with large cells and mitotic features. Histological examination showed two different main growth patterns: solid sheets of undifferentiated polygonal cells with papillary features and rhabdoid cells. Immunohistochemically, these rhabdoid cells were positive for vimentin, epithelial membrane antigen, smooth-muscle actin, cytokeratin, S-100 protein, and glial fibrillary acidic protein. Electro-microscopically, the typical rhabdoid cells contained whorled bundles of intermediate filaments in their cytoplasm. A rhabdoid tumor is a clinicalpathological entity and emphasizes the necessity to distinguish this unique tumor from other pediatric central nervous system neoplasms. Cytopathological features, immunohistochemistry and electro-microscopy differential diagnoses are discussed.
Los tumores de tipo rabdoide primarios en cualquier sitio son raros y en el sistema nervioso central son extremadamente raros y ocurren principalmente en niños, el tumor teratoide/rabdoide es el tumor más frecuente dentro de este grupo y de evolución clínica fatal. El tumor neuroectodermico primitivo, medulobalstoma y al carcinoma de plexos coroides son tumores generalmente muestran aspectos clínicos radiológicos e histológicos similares, con evolución diferente. Presentamos el caso de un hombre joven de 18 años que inició con cefalea vómitos y ataxia. La imagen de TC muestra tumor en fosa posterior. Se realizó resección total del tumor. En el estudio transoperatorio se observó neoplasia maligna de células grandes con mitosis y que formaba estructuras papilares. Histológicamente se observaron dos patrones diferentes, uno formado por nidos sólidos de células poligonales indiferenciadas con formación de estructuras papilares y el otro con abundantes células grandes de aspecto rabdoide. Por inmunohistoquímica las células de aspecto rabdoide fueron positivas para vimentina, antigeno de membrana epitelial, actina de músculo liso, citoqueratina, y proteína S-100, La PGAF fue focalmente positiva. Se realizó microscopía electrónica de las células rabdoides que mostraban nidos irregulares de filamentos intermedios intracitoplasmicos y lamina basal. El tumor rabdoide cerebral es clínica como histológicamente una rara entidad en la población pediátrica. Se discute el aspecto citopatológicas de inmunohistoquímica y de microscopia electrónica y sus diagnósticos diferenciales.