Abstract
Undifferentiated carcinoma of the temporal bone is an extremely rare disease, and has always been associated with metastatic disease from other sites. This is a case report of a 70-year-old gentleman presented initially with facial nerve palsy and features of chronic otitis media with cholesteatoma. He underwent mastoidectomy and was diagnosed with undifferentiated carcinoma of the temporal bone by the histopathological examination of the biopsied tissues from the mastoid and middle ear. A thorough assessment for possible primary lesion including blind biopsy of the nasopharynx was negative. He was treated with radical radiotherapy alone as he refused further surgery despite residual tumour in middle ear, and responded well with no recurrence noted clinically and radiologically after 5 years of follow-up. Primary undifferentiated carcinoma of the temporal bone is a possible new entity and may carry good prognosis as it responded well to radiotherapy as other undifferentiated carcinoma in head and neck.

Key words: Temporal bone, undifferentiated carcinoma, facial nerve, surgery, radiotherapy