Previously-published research has given credence to the notion that psychotherapy extends the lives of people with cancer. In fact, one in four cancer patients believe that science supports the idea that participating in group therapy will extend their lives.
However, in a paper appearing in the May issue of the Psychological Bulletin, researchers at the University of Pennsylvania School of Medicine concluded ? after an extensive research review ? that there is no compelling evidence linking psychotherapy or support groups with survival among cancer patients.
“We all wish that psychotherapy could prolong life, because it appeals so strongly to firmly-rooted notions that a person should be able to control their destiny,” says lead author, James C. Coyne, PhD, Co-Leader, Cancer Control and Outcomes Program, Abramson Cancer Center and Professor of Psychology in Psychiatry at Penn. “We have a special responsibility to cancer patients to clarify that the reasonable goal of psychotherapy and support groups is to improve their quality of life, not extend it.”
Two studies in particular ? Spiegel et al., 1989 and Fawzy et al., 1993 ? have been widely interpreted as providing early support for the idea that psychotherapy promotes survival among cancer patients. However, the authors report that the studies had numerous methodological and analytical flaws, including the fact that they were not designed to test the hypothesis that psychotherapy extends the lives of cancer patients. The study investigators had redefined the purpose of their studies after looking at their data ? a practice that is generally not acceptable in biomedicine and that often leads to claims that will not be validated in subsequent studies.
Coyne notes, “If these studies had been testing medications, rather than psychotherapy, no one would have paid much attention to the redefined outcome of improved survival, and leading medical journals would probably not have accepted the papers, given their other flaws.”
In the years following these studies, additional studies have been conducted to test for the effect of psychotherapy extending the lives of cancer patients, but none have demonstrated a survival benefit that could logically be attributed to psychotherapy. In biomedicine, a large-scale trial would not be considered warranted for cases in which a hypothesis was interesting but improbable given the available data. Therefore, the authors conclude that there is not enough basis to justify investing additional funding for research in this area.