Symptom clusters in patients with newly-diagnosed brain tumors.

A symptom cluster comprises three or more concurrent symptoms. There is a paucity of symptom cluster research in cancer patients. Data from a previously conducted clinical trial were analyzed to search for symptom clusters. This phase III, placebo-controlled, double-blind, prospective, randomized clinical trial of 66 patients assessed the effect of prophylactic d-threo-methylphenidate (d-MPH) on quality of life (QOL) in newly diagnosed brain tumor patients receiving brain radiation therapy. Patients received 5-15 mg of d-MPH or placebo twice daily starting on week 1 of radiation therapy and continuing for 8 weeks post radiotherapy. QOL data were collected at baseline; the end of radiation therapy; and 4, 8, and 12 weeks following radiation therapy using the Functional Assessment of Cancer Therapy (FACT), the FACT-Brain subscale, and the Center for Epidemiologic Studies Depression Scale. Exploratory factor analysis, multidimensional scaling (MDS), and cluster analysis were used to search for symptom clusters. The trial failed to show a treatment effect; patients receiving d-MPH or placebo were analyzed together to search for clusters. Two symptom clusters were identified using exploratory factor analysis--a language cluster including difficulty reading, writing, and finding the right words and a mood cluster including feelings of sadness, anxiety, and depressed mood; these clusters were supported by MDS and cluster analysis. Our results suggest that interventions that target both cognitive function and mood should be considered in this patient population. Further research on symptom clusters in brain tumor patients is needed.