Stereotactic body ablative radiotherapy for reirradiation of small volume head and neck cancers is associated with prolonged survival: Large, single-institution, modern cohort study

Background: Recurrent head and neck cancer has poor prognosis. Stereotactic body radiotherapy (SBRT) may improve outcomes by delivering ablative radiation doses.

Methods: We reviewed patients who received definitive-intent SBRT reirradiation at our institution from 2013 to 2020. Patterns of failure, overall survival (OS), and toxicities were analyzed.

Results: One hundred and thirty-seven patients were evaluated. The median OS was 44.3 months. The median SBRT dose was 45 Gy and median target volume 16.9 cc. The 1-year local, regional, and distant control was 78%, 66%, and 83%, respectively. Systemic therapy improved regional (p = 0.004) and distant control (p = 0.04) in nonmetastatic patients. Grade 3+ toxicities were more common at mucosal sites (p = 0.001) and with concurrent systemic therapy (p = 0.02).

Conclusions: In a large cohort of SBRT reirradiation for recurrent, small volume head and neck cancers, a median OS of 44.3 months was observed. Systemic therapy improved regional and distant control. Toxicities were modulated by anatomic site and systemic therapy.