RESUMO
OBJECTIVE@#To investigate the features and diagnosis way of small round cell tumor of nasal sinus and bases of skull.@*METHOD@#A retrospective analysis of 123 case with small round cell tumor of nasal sinus and bases of skull were carried out in our hospital in past ten year. Clinical, histological, radiological and immunohistochemical characters of these cases were studied.@*RESULT@#All cases usually complained of nasal obstruction, headache, diplopia, nasal mucus with bleeding, vision or weight loss. Expansible or infiltrative lumps were found in nasal sinus or bases of skull in radiological examination. A lot of small round cells were found in these tumors in histological pathology. At least 5-6 cell, tissue or tumor markers were examined immunohistochemically in most of cases before the final diagnosis were made. In some cases over 20 markers were examined. Five cases were carried out transmission electron microscope examination, special features such as desmosome and myofilament were found.@*CONCLUSION@#Clinical symptom, physical signs and radiological finding can supply malignant evidences of these tumors. Histological examination can make certain that they are small round cell tumors, but final diagnosis is still hard to make only by these. Immunohistochemical examination of various markers can tell the original characters of the specimen tissues, it is the key for final diagnosis. Transmission electron microscope examination is another helpful way for diagnosis.