Measures of efficacy and benefit in cancer therapy

Abstract

 With the progress of cancer therapy, there have been increasing demands for validation of the measures of its therapeutic efficacy and benefit. We briefly review such measures, including 5-year survival rate, cure rate, median and mean survival times, log-rank statistics and hazard ratio, as well as the endpoints advocated by the US Food and Drug Administration (FDA). These are evaluated from the perspective of patients. The results show that 1) although the 5-year survival rate is easily appreciable to patients and non-statisticians, it tends to overestimate the cure rate; 2) generally, cured patients have longer survival times and better QOL than those whose deaths are merely delayed, so the cure rate should be the measure of primary importance, rather than the time to event, particularly if the group under study has a potentially curable fraction; and 3) if the time to death from cancer is delayed, the QOL may be reduced against the patient's wishes. In conclusion, measures of efficacy and benefit in cancer therapy have yet to be improved by giving more consideration to cure rate and patient preference.