The long-term burden of a symptom cluster and association with longitudinal physical and emotional functioning in breast cancer survivors.

Background: Fatigue, insomnia and pain are some of the most common and distressing symptoms experienced during breast cancer (BC) treatment and survivorship. The symptoms have been found to impact one another and to form a symptom cluster, and greater severity of the symptoms may be negatively associated with physical and emotional functioning in survivorship. In exploratory analyses from a randomized controlled trial examining the effect of progressive resistance training on the development of lymphedema after BC, we aimed to examine the burden of the symptom cluster fatigue-pain-insomnia, and its prognostic value for long-term symptom severity as well as emotional and physical functioning.