That adjuvant hormone therapy lowers the risk of breast cancer recurrence by approximately 40 per cent and breast cancer specific mortality with approximately 30 per cent has been shown in numerous studies. Proportion of women that stop taking their medication ranges from 20-70 per cent but few studies have addressed predictors of discontinuation of adjuvant hormone therapy.
In a study published in June 2015 (Wei He, Fang Fang, Catherine Varnum, Per Hall, Mikael Eriksson, Kamila Czene, Journal of Clinical Oncology) it was found that women at higher risk of discontinuation were more likely to have a family history of ovarian cancer, to be younger than 40 years or older than 65 years, and to use analgesics and hypnotics /sedatives. These results are most clinically relevant since doctors can use the results to identify factors that predict which patients will stop using adjuvant hormone therapy.
The research on discontinuation is continuing with a focus on breast cancer patients that after discontinuation later takes up therapy. To restart therapy is to the benefit of patients but the prognosis does not reach that of those patients that sticks to therapy. However, it is significantly better than for those who stops altogether. The paper is accepted for publication in Journal of the National Cancer Institute.