Characteristics of advanced cancer patients with cancer-related fatigue enrolled in clinical trials and patients referred to outpatient palliative care clinics

Context: Limited published data exist on whether characteristics of patients with advanced cancer enrolled in cancer-related fatigue clinical trials (CCTs) differ from patients in outpatient palliative care clinics (OPCs).

Objectives: The primary aim of this study was to compare the characteristics of two groups of patients with advanced cancer and moderate-to-severe fatigue: patients in CCTs and patients at an OPC.

Methods: We retrospectively reviewed the records of 337 patients who were enrolled in one of five CCTs for advanced cancer patients at The University of Texas M. D. Anderson Cancer Center as well as the records of 1896 consecutive patients who were referred to our OPC from January 2003 through December 2010. Patients with fatigue scores of ≥4/10 (measured by the Edmonton Symptom Assessment System [ESAS]) were eligible (1252 OPC patients and 337 CCT patients). Patient characteristics, ESAS scores, and survival times were compared using Chi-square tests, Wilcoxon rank sum tests, and the Kaplan-Meier method.

Results: Compared with the CCT patients, OPC patients were more likely to be older (58 vs. 59 years; P=0.009) and male (38% vs. 52%; P<0.001). The most common primary cancer type was breast cancer (22%) in the CCT patients and lung cancer (23%) in the OPC patients (P<0.001). The median ESAS scores in the OPC and CCT groups, respectively, were 6 and 4 for pain (P<0.001), 7 and 7 for fatigue (P=0.525), 3 and 2 for depression (P=0.004), 3 and 2 for anxiety (P<0.001), 3 and 2 for dyspnea (P<0.001), and 43 and 32 for the symptom distress score (P<0.001). The median overall survival times were 17.9 months (95% CI 13.5-22.3 months) in the CCT group and 3.8 months (95% CI 3.5-4.1 months) in the OPC group (P<0.001).

Conclusion: Baseline characteristics and overall survival times significantly differed between patients enrolled in the CCT and OPC groups. Therefore, we conclude that the results of CCTs cannot be generalized to patients being treated in OPCs.