Refusal of radiation therapy and its associated impact on survival

Abstract

Objectives: Despite evidence that radiation therapy (RT) improves outcome in multiple malignancies, some patients with strong clinical indications still refuse RT. Data on factors associated with RT refusal are limited. Furthermore, the effect of RT refusal on outcome has not been clearly defined.

Methods: Patients with nonmetastatic cancer, diagnosed between 1988 and 2005, were identified in the Surveillance, Epidemiology, and End Results database. Univariate and multivariate methods were used to identify factors associated with RT refusal and the impact of refusal on outcomes.

Results: On univariate analysis, age, sex, marital status, tumor site, and tumor stage were associated with RT refusal (P < 0.001). On multivariate analysis, sex and tumor stage were not found to be associated with RT refusal. In contrast, age, race, marital status, and tumor location were significantly associated with RT refusal. The median survival of compliant patients was 171 months compared with just 96 months among patients who refused RT.

Conclusions: A significant percentage of patients continue to refuse RT despite medical advice and evidence. Subgroups at particular risk of RT refusal include elderly, black and widowed patients. RT refusal is associated with markedly worse clinical outcomes.

FIGURE 1

Rate of RT refusal by year of diagnosis (black line) and associated regression coefficient (gray line). The latter value represents the coefficient associated with each year of diagnosis for a binary logistic regression model of RT refusal (1988 equals the reference category). See Table 3 for regression coefficients of other significant variables in the final model.

FIGURE 2

Overall survival for patients who received recommended RT (black line) and for patients who refused RT (gray line).