Clinical Benefits versus Quality of Life of Patients Receiving Interferon
Bernard Cole, Ph.D., assistant professor of community health (Research), Center for Statistical Science, Brown University (Providence, RI), presented an analysis of the quality of life of melanoma patients receiving interferon alfa-2b therapy following surgery. In a study of 280 patients conducted by the Eastern Cooperative Oncology Group (ECOG), patients who received interferon therapy lived longer and experienced fewer disease relaspses than patients who did not receive interferon therapy. However, the patients who received interferon also experienced substantial, negative side effects that had an adverse effect on their quality of life. These side effects consisted mainly of flu-like symptoms such as fatigue and fever.
The purpose of the research was to evaluate the trade-offs associated with interferon therapy in terms of quality and quantity of life. The researchers used a statistical technique that was specifcally designed for making these evaluations. The technique, Q-TWiST (Quality-adjusted Time Without Symptoms or Toxicity), divided the time following cancer diagnosis for each patient into three health periods: 1) time spent with interferon-related side effects; 2) time following disease relapse; and 3) time without either side effects of interferon or disease relapse.
An analysis of these health periods using data from the ECOG study allowed the researchers to evaluate the benefits of interferon in light of its side effects. For example, the analysis indicated that within the first seven years following diagnosis, patients who received interferon experienced side effects for six months on average, but lived seven months longer than patients who did not receive the drug.
The tradeoff between side-effects and clinical benefits depends on how patients value time in each of these health periods, according to Dr. Cole. Some patients may strongly prefer to avoid side effects, while others may be willing to suffer side effects for the possibility of living longer. The results of the Q-TWiST analysis indicated that regardless of the valuations placed on the health periods, the benefits of interferon offset its side effects. This effect was especially significant for patients who considered interferon side effects to be very manageable but disease relapse to be very devastating.
"This study shows that although there are side effects of interferon therapy that can diminish quality of life, in some cases they are offset by the benefits of therapy," Lynn Mara Schuchter, MD, assistant professor of medicine, Univeristy of Pennsylvania Cancer Center (Philadelphia, PA), said at a press briefing. "The optimal treatment for an individual patient depends on his or her disease severity and preferences regarding time with side effects and disease relapse. The results of this evluation should provide help in choosing the optimal treatment for an individual patient."