Breast Cancer Treatment Works Best Over Longer Period

Chemotherapy for breast cancer provided in a series of one drug after the next improves survival, a new study shows. The findings suggest that a longer course of treatment may be more effective than a shorter course, the authors say.

Researchers compared a longer course of chemotherapy over a six-month time time frame to a shorter, three-month span.

Reporting in the New England Journal of Medicine, the authors tracked outcomes for almost 5,400 women with early stage breast cancer that had spread to at least one lymph node.

Longer Treatment Found to Be Helpful

In the study, the patients were randomly divided into one of three treatment groups. The first group received drugs sequentially (one drug following the next), which involved three drugs -doxorubicin, cyclophosphamide, and docetaxel - over six months.

The second and third groups received drugs concurrently (drugs given more closely together), where women received either two or three of these medications for three months.

After eight years of follow-up, 83 percent of patients in the sequential group were still alive compared to 79 percent of those in the concurrent groups, the authors report.

Disease-free survival was also better in the sequential group, leading to the conclusion that a longer course of treatment remains better than a shorter course, the study says.

However, an accompanying editorial in the journal points out that the side effects associated with the longer program might not be worth the small survival advantage for many women.

"An overall survival advantage of 4 percentage points is only a modest gain in exchange for increasing the dose of chemotherapy agents, doubling the duration of therapy, and markedly increasing acute toxicity," says Dr. Matthew Ellis, Washington University School of Medicine, St. Louis.

End of Menstrual Cycle Beneficial

Study lead author Dr. Sandra M. Swain says a second finding of the study was surprising.

"The surprising finding," says Dr. Swain, "was that younger women who went into early menopause because of their chemotherapy were more likely to live longer. That's something that's not been reported." Dr. Swain is medical director of the Washington Cancer Institute in Washington, DC.

This was true for women's breast cancer that was estrogen-receptor positive (meaning estrogen furthers their growth) or breast cancer that was not.

No menstrual periods (amenorrhea) mean less estrogen is circulating in the body and estrogen is known to fuel certain types of cancers.

But that is not a likely explanation in this study, the authors say, given that amenorrhea also resulted in longer survival even in women whose tumors were estrogen-receptor (ER) negative - that is, their cancers do not respond to estrogen.

Expert Dr. Jay Brooks, at Ochsner Health System in Baton Rouge, Louisiana, says this study gives a hint that women who stop having their periods - even in the patients who are not ER positive - may have a survival advantage.

Always consult your physician for more information.