RESUMO
Las células envolventes olfatorias son células gliales que se encuentran en el bulbo y el nervio olfatorios. Las células de Schwann y las células envolventes del olfatorio presentan características morfológicas e inmunohistoquímicas similares. Sin embargo, las células de Schwann son positivas en la tinción con Leu-7(CD-57) mientras que las células envolventes lo son negativas. Presentamos el caso de un varón de 49 años con pérdida de agudeza visual e hiposmia. Los estudios de TC y RM craneal muestran una lesión extraaxial subfrontal quística, que erosiona la lámina cribosa derecha y capta contraste heterogéneamente. Con resección completa mediante craneotomía bifrontal, el estudio histológico inicial sugería schwannoma, con inmunorreactividad positiva para S100 y negativa para EMA. Sin embargo, la tinción con Leu-7 negativa y el diagnóstico definitivo fue de tumor de las células envolventes del olfatorio. Describimos el sexto caso de tumor de las células envolventes del olfatorio intracraneal subrayando la importancia de las técnicas inmunohistoquímicas en su diagnóstico (AU)
Olfactory ensheathing cells are glial cells located in the olfactory bulb and nerve. Microscopically, both olfactory ensheathing cells and Schwann cells have similar morphological and immunohistochemical features. However, olfactory ensheathing cells are negative for Leu-7(CD-57), whereas Schwann cells are positive. We present the case of a 49 year-old male with a history of visual impairment and hyposmia. Radiological CT and MRI studies showed a subfrontal cystic extra-axial mass, which eroded the right cribriform plate, with heterogeneous contrast enhancement. Total excision of the tumour was performed by bifrontal craniotomy. Histological examination initially suggested a schwannoma, with immunohistochemical staining being positive for S-100 protein and negative for epithelial membrane antigen (EMA). However, the tumour was negative for Leu-7. Accordingly, the final diagnosis was olfactory ensheathing cell tumour. Herein, we describe the sixth case of intracranial olfactory ensheathing cell tumour and stress the important role of immunohistochemical techniques in obtaining a definitive diagnosis
Assuntos
Humanos , Masculino , Pessoa de Meia-Idade , Bulbo Olfatório/patologia , Neoplasias Encefálicas/patologia , Glioma/patologia , Neurilemoma/patologia , Neoplasias de Bainha Neural/patologia , Proteínas S100/análise , Diagnóstico Diferencial , Transtornos da Visão/etiologiaRESUMO
Olfactory ensheathing cells are glial cells located in the olfactory bulb and nerve. Microscopically, both olfactory ensheathing cells and Schwann cells have similar morphological and immunohistochemical features. However, olfactory ensheathing cells are negative for Leu-7(CD-57), whereas Schwann cells are positive. We present the case of a 49 year-old male with a history of visual impairment and hyposmia. Radiological CT and MRI studies showed a subfrontal cystic extra-axial mass, which eroded the right cribriform plate, with heterogeneous contrast enhancement. Total excision of the tumour was performed by bifrontal craniotomy. Histological examination initially suggested a schwannoma, with immunohistochemical staining being positive for S-100 protein and negative for epithelial membrane antigen (EMA). However, the tumour was negative for Leu-7. Accordingly, the final diagnosis was olfactory ensheathing cell tumour. Herein, we describe the sixth case of intracranial olfactory ensheathing cell tumour and stress the important role of immunohistochemical techniques in obtaining a definitive diagnosis.
