The prognostic value of WHO performance status in relation to quality of life in advanced colorectal cancer patients

INTRODUCTION: Performance status (PS) is an established prognostic factor in patients with advanced cancer and is usually scored by the treating physician. The EORTC QLQ-C30 questionnaire as reported by cancer patients is a validated tool to assess quality of life (QoL). Subjectivity plays a role in both assessments, and data on a direct comparison are scarce.

METHODS: We compared the prognostic value for overall survival (OS) of the WHO PS to the baseline physical function scale of the EORTC QLQ-C30 (QLQ-C30 PF) in a prospective randomised phase 3 trial in advanced colorectal cancer (ACC), the CAIRO study. Patients were divided into two groups based on the baseline QLQ-C30 PF. QLQ-C30 PF was considered 'good' if the score was more than 66.7% and 'poor' if 66.7% or less. Results were validated in a subsequent phase 3 study in ACC, the CAIRO2 study.

RESULTS: The median OS for patients with a 'good' QLQ-C30 PF and a 'poor' PF in patients with WHO PS 0 was 20.3 months (n = 300) and 10.4 months (n = 44), in patients with WHO PS 1 16.8 months (n = 125) and 10.1 months (n = 63), and in patients with WHO PS 2 16.2 months (n = 11) and 9.9 months (n = 12), respectively. In a Cox regression model which included other prognostic factors, 'good' versus 'poor' QLQ-C30 PF was significantly prognostic for OS (0.57 95% confidence interval: 0.46-0.72), but not WHO PS. These results were confirmed in the CAIRO2 study.

CONCLUSIONS: We demonstrate in ACC patients that PF, as assessed by patients using the EORTC QLQ-C30, is superior in terms of prognostic value to WHO PS as scored by physicians. Our data support to include the results of baseline EORTC QLQ-C30 PF instead of WHO PS as a stratification parameter in oncology trials.