The five-year survival after a breast cancer diagnosis in Spain is about 83 percent, but about 66 percent suffer fatigue following treatment, researchers say. Lead author Manuel Arroyo of the University of Granada linked psychological disorders and physical pain episodes with fatigue after treatment of a breast tumor. \"Cancer-related fatigue is the symptom that most limits quality of life and is most common in patients that survive cancerous processes,\" Arroyo says in a statement. Fifty-nine female patients treated for breast cancer were tracked for one year after treatment and their psychological and physical condition -- as well tiredness, pain, limited movement, depression, etc. -- was assessed. A statistical procedure allowed inferences to be made similar to those from a larger sample, the researchers say. \"This method means that the data were more reliable and eliminated the problem of having a reduced sample size,\" Arroyo says. \"It is difficult to find volunteers because patients are not often very willing to participate in research after having been through such harsh treatment.\" The team of researchers linked sensory hypersensitivity, limited movement and certain psychological conditions with fatigue observed following cancer treatment, Arroyo says. \"These findings should motivate patient support programs which improve their psychological condition and offer resources that can reduce pain,\" Arroyo says. \"If fatigue is not treated, patients can suffer it for years, having a serious physical, emotional, social and economic impact.\"