Although uncommon, primary malignant tumours of the external auditory canal (EAC) are associated with a poor prognosis as they often present late. In this study the authors evaluate the clinical and pathological factors associated with treatment and outcome of EAC carcinomas. They identified 23 patients over a 20-year period for inclusion, with a range of pathology from T1 to T4. Interestingly, in half of patients the main presenting complaint was otorrhoea, closely followed by otalgia. The majority of cases of EAC carcinoma were SCC (70%), followed by adenoid cystic carcinoma (22%), basal cell carcinoma (4%) and verrucous carcinoma (4%). The majority of patients underwent surgical treatment (83%), including total canal resection, lateral temporal bone resection, parotidectomy and supraomohyoidal neck dissection. Only one patient received postoperative chemoradiotherapy (CRT), whilst seven patients had postoperative radiotherapy (RT). The 5-year survival rate was 75.2% and 10-year survival was 60.2%. SCC patients had a significantly poorer prognosis compared to the other histological subtypes. As one might expect, those patients who had surgical treatment with post-operative CRT / RT had a significantly better prognosis than those patients who had unresectable disease. Although the numbers in this study are small, it highlights the importance of having a high index of suspicion of EAC carcinoma, as it presents with very non-specific symptoms. No patients in the study had cranial nerve palsies, and the presence of these suggests a very poor prognosis indeed. Perhaps the main conclusion to take away is that EAC carcinomas should be treated aggressively with complete resection and postoperative CRT. 

Carcinoma of the external auditory canal: histological and treatment groups.
Hosokawa S, Mizuta K, Takahashi G, et al.
B-ENT
2014;10:259-64.
Share This
CONTRIBUTOR
Sunil Sharma

Alder Hey Children's Hospital, UK.

View Full Profile