[Undifferentiated carcinoma of the maxillary sinus. Clinical case].

A poorly differentiated squamous cell carcinoma arising in the left maxilla of a seventy year-old female is reported in the present paper. The patient was seeking treatment for a maintained nose bleeding which appeared several days before. In addition to the report of the clinical case, the authors rewied the main features of the disease, emphasizing the low frequency of the condition, as compared to other neoplasic involvement arising in the head and neck. Due to the advanced stage of the case herewith reported, the patient underwent no treatment.