TUESDAY, June 29 (HealthDay News) -- Slightly less than half of
early-stage breast cancer patients complete their full prescribed
course of hormone therapy, finds a new study.
U.S. researchers examined the automated pharmacy records of
8,769 women diagnosed with stage 1, 2 or 3 hormone-sensitive breast
cancer between 1996 and 2007. Each woman filled at least one
prescription for hormone therapy within a year of breast cancer
diagnosis. The women used tamoxifen (43 percent), aromatase
inhibitors (26 percent) or both (30 percent).
Overall, only about 49 percent of the women completed their full
prescribed regimen of hormone therapy, the study found. After 4.5
years, 32 percent of the women had stopped taking their hormone
therapy. Of those who did not stop, 72 percent finished on schedule
(meaning they took their medication more than 80 percent of the
Those most likely to discontinue hormone therapy early were
found to be women younger than 40. Among these women and women
older than 75, those who had a lumpectomy rather than a mastectomy
and those who had other medical illnesses were more likely to
discontinue the therapy. Those most likely to complete 4.5 years of
hormone therapy were Asian/Pacific Islanders, women who'd undergone
chemotherapy in the past, those who were married and women who had
longer prescription refill intervals.
In general, the researchers said, women stop hormone therapy
early for a variety of reasons, including such side effects such as
joint pain, hot flashes and fatigue; a lack of understanding about
the benefits of the therapy; and the high cost of medications and
"Physicians are often unaware of patient compliance, and this is becoming an increasingly important issue in cancer," the study's leader, Dr. Dawn Hershman, an associate professor of medicine and epidemiology at Columbia University Medical Center, said in a news release from the Journal of Clinical Oncology. The study appears online June 28 in the journal.
"It's very disturbing that patients under 40 had the highest discontinuation rates because those patients have the longest life expectancy," Hershman said. "If we can better understand the issues surrounding compliance with hormonal therapy, this might help us understand why patients don't adhere to other treatments that are moving out of the clinic and into the home, such as oral chemotherapy, as often as we would like."
The American Cancer Society has more about
hormone therapy for breast cancer.
Journal of Clinical Oncology
, June 28, 2010, news release.