Primitive neuroectodermal tumor of paranasal sinuses: diagnosis and treatment/Tumor neuroectodermico de seios paranasais: diagnostico e tratamento

Primitive neuroectodermal tumours (PNET) are rare and highly aggressive neoplasms found mainly in children and young adults. They are classified in peripheral or central according to their origin. The diagnosis is based on clinical history, computed tomography and magnetic resonance imaging, but the pathological study is the only way to confirm it. It's very important to distinguish the PNET from other small cell round cell tumors--such as lymphoma, Ewing's sarcoma and rhabdomyosarcoma --through immunohistochemical specific markers. The treatment includes surgical resection, chemotherapy and irradiation. The prognosis is poor and the survival rate is variable. This article aims to discuss the clinical, imaging and histological features of the primitive neuroectodermal tumors and their treatment. KEYWORDS: Neuroectodermal tumors, primitive, peripheral; Ewing's sarcoma/pathology; Paranasal sinuses Tumores neuroectodermicos primitivos (PNET) sao neoplasias raras e extremamente agressivas encontradas principalmente em criancas e adultos jovens. Sao classificados em perifericos ou centrais, de acordo com sua origem. O diagnostico baseia-se na historia clinica, sendo essenciais exames de imagem, como tomografia computadorizada e ressonancia magnetica, e, para a confirmacao, estudo anatomopatologico. E importante distingui-los de outros tumores de celulas redondas pequenas, como linfoma, sarcoma de Ewing extraosseo e rabdomiossarcoma, exigindo diferenciacao imunoistoquimica atraves de marcadores especificos. O tratamento envolve cirurgia, quimioterapia e radioterapia, sendo o prognostico pobre e a sobrevida bastante reservada. O objetivo deste artigo e discutir as caracteristicas clinicas, radiograficas e histologicas dos tumores neuroectodermicos primitivos e seu tratamento. DESCRITORES: Tumores neuroectodermicos primitivos perifericos/patologia; Sarcoma de Ewing/patologia; Seios paranasais