Assessment of functional status in patients with invasive carcinoma of the urothelial tract

Performance status score is an important prognostic factor for response and survival for patients entering clinical trials. Evaluation of the functional status of the patients should be considered when retrospective studies on prognostic factors are performed. However, the methodologic problems of evaluating performance status retrospectively are unknown. The aim of this study was to evaluate the reliability and validity of retrospective assessment of performance status based on information from patient records. The level of performance status was analyzed in relation to duration of survival after primary or recurrent carcinoma of the urinary tract. The records of 149 patients with primary urothelial carcinoma and 53 patients with recurrent disease were blindly scored twice by two investigators according to the World Health Organization (WHO) performance status scale. The median time of observation was 109 months (range 3–219); 13 patients were alive at the time of follow-up. When scores of the performance were compared for patients separated in two groups, good performance (WHO scores 0 and 1) versus poor performance status (score >1), the intraobserver overall agreement for the assessments varied from 82% to 89%, whereas the interobserver agreement varied from 76% to 86%. The range of the intra- and interobserver kappa coefficients (95% CI) were 63% to 72% (52% to 83%) and 49% to 68% (40% to 79%), respectively. All four assessments were significantly related to survival (p < 10−4). Multivariable proportional hazard regression analysis showed that gender, platelet count, level of liver enzymes, and each of the four assessments of performance status (analyzed in four separate statistical models) were significant prognostic factors. Retrospective scoring of performance status is a reproducible and reliable tool that provides additional prognostic information. Optimal retrospective evaluation of the simultaneous effect of multiple prognostic factors should therefore include an assessment of the functional status of the patient.