Risk of cerebrovascular events in elderly patients after radiation therapy versus surgery for early-stage glottic cancer

Int J Radiat Oncol Biol Phys. 2013 Oct 1;87(2):290-6. doi: 10.1016/j.ijrobp.2013.06.009. Epub 2013 Jul 29.

Abstract

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.

MeSH terms

  • Aged
  • Aged, 80 and over
  • Analysis of Variance
  • Carcinoma, Squamous Cell / pathology
  • Carcinoma, Squamous Cell / radiotherapy
  • Carcinoma, Squamous Cell / surgery
  • Cause of Death
  • Cerebrovascular Disorders / etiology*
  • Cerebrovascular Disorders / mortality
  • Female
  • Glottis
  • Humans
  • Laryngeal Neoplasms / pathology
  • Laryngeal Neoplasms / radiotherapy*
  • Laryngeal Neoplasms / surgery
  • Male
  • Postoperative Complications / etiology
  • Postoperative Complications / mortality
  • Risk
  • SEER Program
  • Stroke / etiology
  • Stroke / mortality