CA: A Cancer Journal for Clinicians, Vol 44, Issue 2 109-114, Copyright © 1994 by American Cancer Society
Cancer therapy and the randomized clinical trial: good medicine?
D. Kaufman
Division of Cancer Treatment, National Cancer Institute in Bethesda, Maryland.
True improvements in the treatment of cancer--by the introduction of new
drugs or novel drug combinations, new therapeutic modalities, or
technologic improvements of old modalities--result in higher response rates
and prolonged survival when compared with existing therapies. When a new
treatment convincingly meets the test of improving survival rates or, at
worst, improving patients' quality of life, it becomes the accepted
standard of care if its side effects are acceptable and its cost is not
prohibitive. Improved therapeutic results can be demonstrated only by
clinical trials with an adequate numbers of patients, appropriate control
subjects, and a sufficient duration of follow-up. Therapeutic breakthroughs
are revolutionary advances in treatment, usually rapidly and dramatically
obvious in comparison with historic controls; demonstration of benefit in
these cases does not usually require randomized trials. Much more common,
however, are new therapies that represent modest, incremental advances over
existing treatment and that usually require randomized comparison trials to
demonstrate convincingly statistically significant improvement. A
randomized clinical trial should test an important hypothesis. It must be
carefully designed to ensure that both groups of patients are comparable in
terms of various prognostic variables and to minimize subtle sources of
bias. An honest belief that both arms of the trial are a priori equal must
be maintained. Meeting these criteria, the randomized clinical trial offers
to the individual cancer patient treatment that should be at least equal to
the best available nonexperimental therapy. This equates with Good
Medicine.
