(RxWiki News) One of the mainstay drugs to treat aggressive breast cancer is very toxic and can cause serious long-term heart problems. A new study has uncovered a treatment regimen that's just effective, but far less toxic.
HER-2 positive breast cancer is one of the most aggressive forms of the disease. Researchers have found that a combination of chemotherapy, followed by a year of the drug Herceptin, improves the outlook for women with this early-stage breast cancer.
"For HER-2 positive breast cancer, chemotherapy + Herceptin regimen offers best results."
One of the primary chemotherapy agents used to treat breast cancer is a drug called Adriamycin. While effective against the cancer, it can cause permanent heart damage.
This study was designed to see if another regimen that by-passed Adriamycin would be effective in treating HER-2 positive disease.
The study recruited 3,222 women with early stage breast cancer between April 2001 and March 2004. Participants were randomly divided into three groups:
- The standard therapy - Adriamycin and Carboplatin followed by Taxotere (ACT)
- ACT + one year of Herceptin (ACTH)
- Taxotere and Carboplatin + one year of Herceptin (TCH)
The women who received Herceptin lived longer, with 92 percent of patients in the ACTH, 91 percent of patients in the TCH group alive after five years, compared to 87 percent in the ACT arm.
Disease-free survival - the time between diagnosis and recurrence - was:
- 75 percent in the ACT group
- 84 percent receiving ACT + Herceptin
- 81 percent in the TCH arm
One of the goals of the study was to test Herceptin with and without Adriamycin to see if effective therapies could be offered without the accompanying dangerous cardiac side effects.
Lead investigator, Dr. Dennis Slamon, of the University of California - Los Angeles, whose work led to the development of Herceptin, said the participants who did not receive Adriamycin fared as well as those who did, while not suffering the toxicities and other dangers associated with ACTH.
Adriamycin side effects included increased risks of congestive heart failure, cardiac dysfunction with no symptoms and "acute" nausea, diarrhea, vomiting and fatigue. Seven of the study participants who received Adriamycin also developed leukemia, a rare but lethal side effect of the drug.
Slamon suggests that this study offers evidence that Adriamycin not be considered in the treatment of any type of early stage breast cancer.
Aggressive HER-2 positive breast cancer accounts for about 20 percent of all diagnoses; it has a poorer outlook and shorter survival rate than other cancers of the breast.
Slamon discovered the link between the presence of the HER-2 genetic mutation and aggressive disease in 1987.
This study was published Oct. 6, 2011 in the New England Journal of Medicine.