The study involved 222 women, aged under 60, who had been diagnosed with a primary operable breast tumour between May 1991 and July 1994. The team collected data on stressful life experiences and depression from 12 months before diagnosis to five years afterwards. Biological factors known to influence prognosis of breast cancer were also taken into account.
They found no evidence that women who have a severely stressful life experience in the year before being diagnosed with breast cancer, or in the five years afterwards, are at any increased risk of developing a recurrence of their disease. In fact, women who had one or more severely stressful life experiences after diagnosis had a lower risk of recurrence than those who did not.
These findings contradict an earlier study that showed severely stressful life experiences increase the risk of recurrence of breast cancer, say the authors. However, different study methods may explain the contradictory results.
"We took the prospective study as the more robust, and the results suggest that women with breast cancer need not fear that stressful experiences will precipitate the return of their disease," they conclude.