Carcinomas of the external auditory canal: Management and results: A multicenter REFCOR propensity score matching study

Objectives: To analyse prognostic factors and survival outcomes of malignant tumors of the external auditory canal, to investigate the role of regional surgery, and adjuvant radiotherapy in early stages and to investigate the role of surgery in operable T4 stage. Setting: A retrospective analysis was conducted on all patients prospectively included in the national database of the French Expertize Network for Rare ENT Cancers (REFCOR) from January 2000 to December 2016. Participants: 103 patients from 19 reference centers were included. A propensity score matching analysis was applied to enable comparisons between treatments. Main outcomes and measures: Event-free survival, overall survival and factors of poor prognosis of the cohort were described. The interest of local and regional surgery and postoperative radiotherapy were evaluated. Results: The factors of poor prognosis on event -free survival were immunosuppression (p = 0.002), Karnofsky status less than 90% (p = 0.02), body mass index less than 19 Kg / m2 (p = 0.0009), peripheric facial palsy (p = 0.0016), and positive margin (p = 0.0006). In early stages, locoregional surgery was associated with an increase in event -free survival (p = 0.003, HR = 0.21) versus local surgery alone, while postoperative radiotherapy was not associated with an increase in event -free survival (p = 0.86, HR = 0.91) or overall (p = 0.86, HR = 0.91). In locally advanced stages, locoregional surgery followed by radiotherapy was associated with an increase in event - free survival (p = 0.03, HR = 0.39) and overall (p = 0.02, HR = 0.34) versus chemoradiotherapy alone. Conclusion and relevance: Regional surgery is recommended for early stages of cancers of the external auditory canal. In operable cases, locoregional surgery followed by radiotherapy is recommended.