Abstract: A 19 years old man was diagnosed withdermatomyositis according to the results of muscle enzyme examination, skin biopsy and muscle biopsy three months ago. The common clinical symptoms of nasopharyngeal carcinoma were not fond during the course of the illness.The serum EB virus antibody and the imaging results of head and neck of the patient were abnormal . Histopathological examination of nasopharynx biopsy tissue showed the features of poorly differentiated squamous cell carcinoma (lymphoepithelial carcinoma). Then the patient was treated with methylprednisolone, hydroxychloroquine?sulfate and radiation therapy. The patient is still in follow-up.

Key words: dermatomyositis, nasopharyngeal carcinoma