The conclusion, published in the Journal of The National Cancer Institute (NCI), is based on a group of 2,838 women diagnosed with cancer that were treated with adjuvant systemic therapy -- chemotherapy or the drug tamoxifen or both -- between 1985 and 2001.
Eighty-nine percent of the women in the study group had no recurrence of cancer five years after treatment, or about 10 years after they were initially diagnosed with cancer, said Abenaa Brewster, of the Anderson Cancer Center at the University of Texas at Houston, the study's main author.
Eighty percent of the women had no recurrence 10 years after treatment, or 15 years after diagnosis, Brewster added.
Five years after treatment, the risk of a resurgence of breast cancer is seven percent for women who have the least advanced tumour -- stage one -- and of 11 and 13 percent respectively for cancers of stages two and three, the researchers said.
"Now we can tell some women, within a certain percentage, their future risk of recurrence and clinicians may be able to make more informed decisions regarding prescription of extended adjuvant endocrine therapy," Brewster wrote.
More than 180,000 new cases of breast cancer are expected to be diagnosed in the United States in 2008, and some 40,000 women die each year of breast cancer, according to American Cancer Society figures.