Predictors of Survival and Recurrence after Temporal Bone Resection for Cancer

Abstract

Malignant tumors of the temporal bone and external auditory canal are uncommon, with annual incidence estimated at between 1 and 6 per million.1,2 Cancers of the external auditory canal/temporal bone comprise <0.2% of head and neck cancers.3 The rarity and anatomic complexity of these tumors hampered the development of an en bloc ablative operation until 1954, when Parsons and Lewis4 from Memorial Hospital in New York first described the technique of subtotal temporal bone resection. Conley and Novack5 refined this technique further in 1960 with the description of lateral temporal bone resection. Subsequent developments in imaging, microsurgery, reconstruction, and neuroanesthesia have all contributed to advancements in skull base surgery. As a result, oncologic temporal bone procedures, including lateral, subtotal, and total temporal bone resection, have become the standard of care for malignant disease involving the external auditory canal/temporal bone. Survival and recurrence outcomes in patients with cancer of the external auditory canal/temporal bone have been reported in several single-institution series. Most cohorts have been limited to squamous cell histology, and comprehensive outcomes analyses have been limited.2,6–24 Further complicating analysis, there is no recognized American Joint Committee on Cancer (AJCC) or Union Internationale Contre le Cancer (UICC) staging system for tumors of the external auditory canal/temporal bone, with multiple systems having been proposed.3,16,25,26 To date, the most widely used system is the University of Pittsburgh staging system, first described in 1990 by Arriaga and colleagues25 and modified in 2000 by Moody et al.3 Other than Pittsburgh stage and surgical margin status, no other factors have been consistently demonstrated to be associated with outcome, and multivariable analyses of factors affecting outcome have not been reported.7,16,20,21 Such a comprehensive analysis of patient and tumor characteristics that are predictive of survival outcomes would aid clinical decision making and risk stratification. The objective of this study was to identify factors predictive of survival and recurrence in a contemporary cohort of patients undergoing temporal bone resection for cancer involving the external auditory canal/temporal bone.