[Clinical features and prognostic factors for early-stage external auditory canal carcinoma]

Objective:To analyze the clinical features and the prognostic factors of early-stage external auditory canal carcinoma. Methods:Data from 36 patients with early-stage external auditory canal carcinoma（T1, T2） treated in Department of Otolaryngology, Xijing Hospital, Air Force Military Medical University from January 2008 to June 2020 were reviewed retrospectively, including clinical manifestations, surgical and treatment methods, pathological types and disease status. The relationship between survival rate and the prognostic factors was compared using Kaplan-Meier method, and the independent risk factors were analyzed by Cox proportional hazards model. Results:There were 36 patents with early-stage external auditory canal carcinoma. The common initial symptoms were otalgia（66.7%）, otorrhea（41.7%） and hearing loss（30.6%）. The most common histopathologic types were adenoid cystic carcinoma（50.0%） and squamous cell carcinoma（33.3%）. Among the patients, 21 patients（58.3%） were initially treated, 9 patients（25.0%） were treated with salvage therapy, and 6 patients（16.7%） were re-surgery after recurrence. The 5-year disease-specific survival（DSS）, disease-free survival（DFS） and relapse-free survival（RFS） were 82.3%, 64.0% and 73.0% respectively. Seven cases （19.4%） relapsed after surgery. For 5-year survival rate, the lateral temporal bone resection with superficial parotidectomy（DSS 91.7%, DFS 83.9%） is higher than the lateral temporal bone resection only（DSS 77.8%, DFS 55.6%） and sleeve resection（DSS 75.0%, DFS 56.0%）, but there was no significant difference（P>0.05）. In these patients, the postoperative radiotherapy and disease status had no significant impact on the survival rate. Additionally, there was no obvious correlation between recurrence and age, gender, stage, histopathologic types, operation methods and postoperative radiotherapy（P>0.05）. But there were significant differences between histopathologic types and DSS or DFS（P<0.05）. Multivariate regression analysis showed that histopathologic type was an independent prognostic factor for DFS. Conclusion:There are no specific clinical manifestations for early-stage external auditory canal carcinoma, such as otalgia and otorrhea. Histopathologic types have a direct impact on the patients'prognosis. Thus, individualized treatment should be applied based on pathologic findings to improve the survival rate.