Purpose: The aim of this study was to explore the presence of symptom clusters in patients with advanced cancer.
Patients and methods: Patients with metastatic cancer referred to an outpatient palliative radiation therapy clinic were asked to rate their symptom distress using the Edmonton Symptom Assessment Scale (ESAS). Baseline demographic data were obtained. To determine interrelationships between symptoms, a principal component analysis with "varimax rotation" was performed on the 9 ESAS symptoms.
Results: Between January 1999 and January 2002, a total of 1296 patients with metastases provided complete baseline data on the ESAS. The most common primary cancer sites were lung, breast, and prostate. Fatigue was the highest scored symptom, followed by poor sense of well-being, pain, lack of appetite, and drowsiness. The 4 most prevalent symptoms were poor sense of well-being (92.7%), fatigue (92.2%), drowsiness (79.7%), and anxiety (78.7%). Three symptom clusters were found. Cluster 1 included lack of appetite, nausea, poor sense of well-being, and pain. Cluster 2 included fatigue, drowsiness, and shortness of breath. Cluster 3 included anxiety and depression.
Conclusion: More work needs to be done on symptom cluster research, especially in setting a consensus in methodology.