Background: Few studies incorporate patient self-assessment scales in prognostic models of survival prediction. The Edmonton Symptom Assessment Scale (ESAS) is commonly used as a symptom screening tool in cancer patients.
Objective: The goal of this study was to evaluate the prognostic value of the ESAS for survival prediction in the advanced cancer population.
Materials and methods: Patients completed the ESAS and demographic information prior to palliative radiotherapy consultation and at follow-up at the Odette Cancer Centre between 1999 and 2009. Generalized estimating equation (GEE) methodology was applied to analyze ESAS trends within the last months of life. One-way analysis of variance (ANOVA) with repeated measurements was used to characterize trends between time periods.
Results: ESAS records (2377) from 808 patients (433 male and 375 female) were included in this cohort. Median age was 68 years (range 32-95) with median Karnofsky performance status (KPS) of 60 (range 10-100). Primary cancer sites were of the lung (36%), breast (20%), and prostate (19%). All nine ESAS symptoms significantly deteriorated in the last 4 weeks immediately before death when compared with those scores in the preceding months. At one week prior to death, the worst ESAS symptoms experienced by patients were fatigue, appetite, and well-being with mean scores of 7.4, 6.9, and 6.1, respectively.
Conclusions: All ESAS scores significantly worsened in the last 4 weeks prior to death compared with those in the previous months. Sudden deterioration of the global ESAS symptoms may predict impending death. Future studies on a prognostic model should incorporate both ESAS symptom severity and trends.