[Clinical analysis of adenoid cystic carcinoma of external auditory canal].

Objective: To explore methods of treatment for adenoid cystic carcinoma of external auditory canal, and discuss the correlating factors that effect prognosis.

Methods: A retrospective analysis of 19 cases of adenoid cystic carcinoma of external auditory canal treated from 1988 to 2004 was carried out. Based on University of Pittsburgh TNM staging system of external auditory canal carcinoma, 19 cases were classified into groups as 5 cases in T1, 2 in T2, 6 in T3, and 6 in T4. Local resection was performed in cases in stage T1 and T2, while radical mastoidectomy or temporal bone resection was performed in stage T3 and T4. Radiotherapy was applied after operation. Relapsed cases with isolated metastasis were treated by surgery. Multiple metastasis were treated with radiotherapy.

Results: The follow-up time is from 6 months to 19 years, and the median is 44 months. There're 8 cases with more than 5 years' follow-up. Twelve patients relapsed and 7 had metastasis but 4 died. The cases with positive incisal edge after first operation relapsed even treated with radiotherapy. In recurrent cases, 9 cases received more than 2 operations, 8 more than 3, and 4 received 4 operations.

Conclusions: The adenoid cystic carcinoma of external auditory canal grows insidiously, and relapses frequently. But the patients can live long with neoplasm implanted. A wide surgical excision combined with post operative radiotherapy was proposed, and negative incision edge should be confirmed. Recurrent cases can be treated with several operations to elongate survival. Multiple relapses will cause metastasis more frequently. Metastasis is the main reason to cause death.