Squamous Cell Carcinoma of the External Auditory Canal: Treatment Results of 15 Cases

BACKGROUND AND OBJECTIVES: The management of external auditory canal (EAC) squamous cell carcinoma (SCC) is very difficult because the structure of the temporal bone is complicated. We aimed to analyze the surgical results of EAC SCC and propose a treatment protocol. SUBJECTS AND METHOD: Fifteen patients with EAC SCC who underwent operations between July 1984 and June 2001 were analyzed. We divided the patients into five classes according to the extent of tumor progression. In patients classified under Class I, the tumor involved the cartilaginous ear canal. Tumors of patients within Class II involved the bony ear canal or mastoid cortex. Tumors that involved the deep structures of the temporal bone but limited involvement of within the middle ear cavity were classified under Class IIIA. In Class IIIB, tumors involved the facial canal, the base of the skull, or mastoid air cells. In Class IIIC, tumors involved the cochlea, the medial wall of middle ear, dura, sigmoid sinus, or other structures such as the parotid gland, carotid canal, or petrous apex. We analyzed data concerning patients and tumors, surgical methods, and surgical outcomes. RESULTS: The number of patients classified under Class I, Class II, Class IIIA, Class IIIB and Class IIIC were 3, 3, 2, 1, and 6, respectively. Surgical approaches were local canal resection, partial temporal bone resection (TBR), subtotal TBR, and total TBR. Follow up period was 5 to 138 months with a mean (+/-SD) of 40 months (+/-37.5), and the five-year disease free survival rate was 40.6%. CONCLUSION: From this study, we suggest the treatment modality for the EAC SCC. We recommend a partial TBR for surgery of Class I or Class II EAC SCC cancers, a subtotal TBR for Class IIIA, and a total TBR when it is close to Class IIIB or Class IIIC