Fatigue and quality of life: lessons from the real world.

The impact of fatigue on the quality of life of oncology patients is substantial and under-recognized. Fatigue in these patients may begin with a simple decrease in physical activity, but can progress to include a wide range of negative effects that often culminate in patients feeling out of control, lonely, and isolated. In general, surviving cancer patients experience some limitations after the end of treatment but ultimately attain a reasonably good level of functioning. An examination of subpopulations and further analyses of data suggest, however, four different recovery patterns. Patients may: A) improve in their functioning, reach a plateau at approximately year 2 or 3, and then remain at relatively high levels of functioning; B) improve initially, but deteriorate again after year 2 or 3, never reaching the normal stage; C) improve, returning to normal; or D) have a very mixed pattern of high levels of fatigue that is, to date, very difficult to interpret. Disturbingly, 60% of the survivors in our population of patients with Hodgkin's disease, who were treated in recent trials of the German Hodgkin Study Group and the European Organization for Research and Treatment of Cancer Lymphoma Group, had medium to high levels of fatigue after 5 cancer-free years. Investigations are essential to determine the current status of long-term survivors in more detail and to link that status to conditions observed during the treatment of acutely ill patients.