Purpose: Australia has one of the highest incidences of cutaneous malignancies in the world, and those in the peri-auricular region may require lateral temporal bone resections (LTBR). This study aims to analyse the diagnostic accuracy of various imaging modalities and the prognostic indicators for survival.
Methodology: A retrospective analysis was performed on all patients who underwent LTBR for cutaneous malignancies between January 2015 and December 2019 at a dedicated tertiary oncology referral centre.
Results: 36 patients were included in this study, with a median age of 79.96 years. Pathology was squamous cell carcinoma in 29 patients, basal cell carcinoma in 4 patients, sarcoma in 2 patients and melanoma in 1 patient. 6 patients underwent concurrent parotidectomy, 2 underwent neck dissection, and 18 underwent both. 9 required free flap reconstruction. R0 resection was achieved in 22 patients. 26 patients received post-operative radiotherapy. Computed tomography (CT), magnetic resonance imaging (MRI) and positron emission tomography (PET) showed good diagnostic accuracy in identifying disease in the parotid gland, external auditory canal, and mastoid bone, but had poor sensitivity in identifying cervical nodal metastasis (CT=0.167, MRI=0.167, PET=0.4). 11 patients recurred with a median duration of 108 days. 36% of patients undergoing salvage surgery recurred while 12% of those undergoing primary resections recurred. Overall survival at 2 and 5 years were 78% with recurrence free survival at 2 and 5 years being 75% and 48%, respectively. Tumour differentiation (p=0.0314) and type 2 LTBR (p=0.0301) showed significant correlation with overall survival, with post-operative N0 staging (p=0.0625), adjuvant radiotherapy (p=0.0664) and primary resections (p=0.0733) approaching significance.
Conclusion: LTBR is an important treatment modality for patients with peri-auricular cutaneous malignancies. Pre-operative considerations for the extent of surgical resection including neck dissections requires clinicoradiological correlation, particularly in patients with poorly differentiated tumours.