Int J Radiat Oncol Biol Phys 2020 01 30;106(1):157-166. Epub 2019 Sep 30.
Department of Radiation Medicine and Applied Sciences, University of California San Diego, La Jolla, California; Center for Precision Radiation Medicine, La Jolla, California. Electronic address:
Purpose: Previous studies have found that patients with head and neck cancer (HNC) with a higher relative hazard for recurrence versus competing mortality (ω ratio) are more likely to benefit from intensive therapy. Nomograms to predict this ratio (ω scores) can be useful to guide clinical management; however, comorbidity and other risk factors are frequently lacking from trial samples.
Methods And Materials: In this study of 7117 US veterans, we evaluated the ability of a ω score nomogram developed from clinical trial data to stratify patients with HNC treated with radiation therapy by their relative risk of cancer progression versus competing mortality. We then fit generalized competing event models to determine the effect of comorbidity and other covariates on the ω ratio.
Results: The ω score was effective in stratifying patients with HNC according to their risk for cancer recurrence relative to competing mortality, especially among patients aged >70 years. Patients with ω score ≥0.80 were more likely to receive intensive therapy compared with patients with a ω score <0.80 (66 vs. 54%; P < .001). On multivariable generalized competing event regression, T2-4 category (relative hazard ratio [RHR], 1.08; 95% confidence interval [CI], 1.01-1.16), N2-3 category (RHR, 1.07; 95% CI, 1.01-1.15), and being employed (RHR, 1.11; 95% CI, 1.03-1.20) were associated with increased ω ratio, and increasing age (RHR, 0.83; 95% CI, 0.78-0.89), Charlson comorbidity index ≥2 (RHR, 0.85; 95% CI, 0.79-0.91), being a current smoker (RHR, 0.90; 95% CI, 0.84-0.96), and lower body mass index (RHR, 0.89; 95% CI, 0.84-0.95) were associated with a decreased ω ratio.
Conclusions: The ω scores are effective in stratifying patients with HNC and are correlated with the intensity of treatment given. The ω scores incorporating comorbidity and other risk factors could help identify patients with HNC most likely to benefit from intensive therapy.