Title: Squamous Cell Carcinoma of the External Ear Canal and the Mastoid.
Abstract: Histopathologic findings of an en bloc resected temporal bone from a patient with a squamous cell carcinoma in the external ear canal and the mastoid were reported. The case was a 75 year-old female died of postoperative impairment of renal function and following meningitis by suture insufficiency. She had had smelly otorrhea and occasional vertigo for three years and otalgia and a mass in the ear for three months. The mass was revealed to be squamous cell carcinoma by biopsies in two occasions. Polytomographies suggested a destructive lesion at the posteroinferior wall of the bony external canal and tumor infiltration fairly restricted in this area. Serially sected specimens showed squamous cell carcinoma invading the posteroinferior wall of the external canal and the adjacent mastoid air cells. Findings of the polytomography coincided well to the finding. However, submucous infiltration of the tumor cells can not be postulated even with this method. Through preoperative check up is mandatory for this aggresive operation.