Risk of Cerebrovascular Events in Elderly Patients After Radiation Therapy Versus Surgery for Early-Stage Glottic Cancer

Purpose: Comprehensive neck radiation therapy (RT) has been shown to increase cerebrovascular disease (CVD) risk in advanced-stage head-and-neck cancer. We assessed whether more limited neck RT used for early-stage (T1-T2 N0) glottic cancer is associated with increased CVD risk, using the Surveillance, Epidemiology, and End Results (SEER)-Medicare linked database. Methods and Materials: We identified patients >= 66 years of age with early-stage glottic laryngeal cancer from SEER diagnosed from 1992 to 2007. Patients treated with combined surgery and RT were excluded. Medicare CPT codes for carotid interventions, Medicare ICD-9 codes for cerebrovascular events, and SEER data for stroke as the cause of death were collected. Similarly, Medicare CPT and ICD-9 codes for peripheral vascular disease (PVD) were assessed to serve as an internal control between treatment groups. Results: A total of 1413 assessable patients (RT, n = 1055; surgery, n = 358) were analyzed. The actuarial 10-year risk of CVD was 56.5% (95% confidence interval 51.5%-61.5%) for the RT cohort versus 48.7% (41.1%-56.3%) in the surgery cohort (P = .27). The actuarial 10-year risk of PVD did not differ between the RT (52.7% [48.1%-57.3%]) and surgery cohorts (52.6% [45.2%-60.0%]) (P = .89). Univariate analysis showed an increased association of CVD with more recent diagnosis (P = .001) and increasing age (P = .001). On multivariate Cox analysis, increasing age (P<. 001) and recent diagnosis (P = .002) remained significantly associated with a higher CVD risk, whereas the association of RT and CVD remained not statistically significant (HR = 1.11 [0.91-1.37,] P = .31). Conclusions: Elderly patients with early-stage laryngeal cancer have a high burden of cerebrovascular events after surgical management or RT. RT and surgery are associated with comparable risk for subsequent CVD development after treatment in elderly patients. (C) 2013 Elsevier Inc.