Fewer than half of nearly 8,000 women with early-stage breast cancer completed their full regimen of hormone therapy according to the prescribed schedule, a new study has found.
Investigators found that younger women were particularly likely to discontinue treatment. The findings underscore the need to both better understand the reasons behind such treatment non-compliance and also develop interventions to reduce it.
"We were surprised to see that so many young women stopped treatment early, despite the fact that the therapy has a proven track record of reducing breast cancer recurrence," said Dawn Hershman, MD, associate professor of medicine and epidemiology at Columbia University Medical Center, who led the study. "Perhaps we need to do a better job of making patients aware that to get the full benefit of treatment, they need to take their medications on time and for the full duration."
While up to five years of oral hormone therapy (such as tamoxifen and aromatase inhibitors) for hormone-sensitive breast cancers is frequently prescribed to reduce the risk of cancer recurrence and death, some previous small studies indicated that only approximately 40 to 60 percent of women finish their recommended course of therapy. In order to provide a more comprehensive perspective, Dr. Hershman and her colleagues examined automated pharmacy records of 8,769 women diagnosed with stage I, II or III, hormone-sensitive breast cancer between 1996 and 2007. They used the records to identify hormonal therapy prescriptions and refill dates. Each woman filled at least one prescription for hormonal therapy within one year of diagnosis. Women used tamoxifen (43 percent), aromatase inhibitors (26 percent) or both (30 percent).