Squamous cell carcinoma of the external ear: 170 cases treated with Mohs surgery

Introduction: Squamous cell carcinoma of the ear (SCC-E) shows high rates of local recurrence (LR) and lymph node metastases (NM). SCC-E is the leading cause of death from nonmelanoma skin cancer. Objective: To determine the LR and NM rates and survival after Mohs micrographic surgery (MMS). Patients and methods: We treated 170 invasive SCC-E with MMS with a mean follow up of 48 months. Mean age was 76 years, 93.2% were male patients, mean size: 1.5 cm, and 61.8% of the tumours were well differentiated. Results: We observed 5 LRs, 2 locoregional recurrences, and 16 NMs in 23 patients. LR and NM rates were 4.1% and 10.6%, respectively. Only 3/25 recurrences occurred after 2 years of follow up. We observed 1(0.6%) distant metastasis (DM) in a patient who also presented LR + NM. Six out of seven cases with LR and 8/18 with NM died of disease, regardless of aggressive surgical rescue with or without adjuvant radiotherapy. Five-year overall survival, disease-free survival, and disease-specific survival were 81%, 82.6%, and 89.7%, respectively. Conclusions: Undeniably, the outcome in SCC-E is determined by locoregional control. DM are sporadic and rarely the cause of death. Systematic reviews and retrospective studies show a solid trend in favor of MMS vs surgical excision. The LR rate of this series (4.1%) is one of the lowest published to date with regard to SCC-E, and confirms this assertion. We observed 10.6% NMs according to other series that treated the whole spectrum of SCC-E. Almost 2/3 of patients with NMs die after therapeutic rescue. We believe that it is essential to identify prognostic factors to select patients for one of the following: close surveillance (ultra-sonography) during the first 2 years after surgery, sentinel node biopsy, or elective treatment of the nodes (surgery or radiotherapy). (C) 2021 British Association of Plastic, Reconstructive and Aesthetic Surgeons. Published by Elsevier Ltd. All rights reserved.