OVERWHELMING FATIGUE IN ADVANCED CANCER

Abstract

Asthenia has two cardinal symptoms: fatigue, defined as easy tiring and a diminishing ability to maintain adequate performance; and generalized weakness, that is, the subjective sensation of difficulty beginning a certain activity (not to be confused with the local or regional weakness of many neurological or muscular disorders)(1). Data on the incidence of asthenia in patients with advanced cancer vary: one report cites generalized weakness in 40 percent of cases; another, in almost half(2,3). We found a lack of energy in 75 percent of the 174 consecutive patients with terminal cancer who participated in four of our studies(4-7). In another study of 54 patients who had advanced breast cancer, we found asthenia in 39 of our 54 patients (72%)(8). No standard measure to assess asthenia exists. Because of this fact, combining several different methods is probably the best approach. The ideal instrument would evaluate the patient's subjective perception of asthenia and measure objective manifestations, such as ability to perform usual daily activities (in the absence of some other impediment). Scales that are simple, rapidly completed, and allow self-assessment are best. (We are now attempting to validate such an instrument.)