Age alone shouldn’t be a factor in determining whether a woman should be offered chemotherapy as part of her breast cancer treatment, according to a new study.

Researchers say the incidence of breast cancer increases with age, and almost half of all new breast cancers in the U.S. are diagnosed in women aged 65 or over.

Chemotherapy (search) after surgery has been shown to reduce the risk of relapse and death in women aged 50 to 69 with early-stage breast cancer. Yet few studies have looked at the benefits and risks of chemotherapy in breast cancer treatment among women 70 and over. Early-stage breast cancer is cancer that has not spread beyond the breast and lymph nodes (search) under the arms. Chemotherapy is used after surgery for early-stage breast cancer to eliminate cancer cells that may still exist.

In this study, researchers found that women 65 and over received the same benefits in preventing breast cancer recurrence and reducing the risk of death due to breast cancer as younger women. Older women did have a higher risk of death, but the study showed the risk was due to other causes than breast cancer.

Researchers say studies exploring new approaches in using chemotherapy as a secondary treatment for breast cancer are now in progress, and these results suggest that older women with early breast cancer who are in otherwise good health but at high risk of recurrence should be allowed to participate in these studies.

Older Women Benefit From Chemo, Too

In the study, which appears in the March 2 issue of The Journal of the American Medical Association, researchers analyzed information from studies on the use of chemotherapy as a secondary treatment for women with breast cancer that had spread to the lymph nodes. The studies were conducted between 1975 and 1999.

A total of 6,487 women with breast cancer were included in these studies, including 542 who were aged 65 or older and 159 who were 70 or over.

The results showed that there was no relationship between a woman's age and living without a return of her breast cancer among the women who received chemotherapy after surgery for breast cancer. Older and younger women appeared to share similar benefits from chemotherapy in terms of preventing disease and reducing the risk of breast cancer death.

The risk of death due to any cause was significantly higher among women aged 65 or older, but this additional risk was attributed to causes other than breast cancer.

Overall, 33 deaths (0.5 percent of all patients) were attributed to the chemotherapy treatment, and older women had higher rates of treatment-related deaths than younger women.

“Our study adds to the increasing number of trials that suggest that older patients in fair to good health tolerate standard chemotherapy regimens, and even more intensive regimens, almost as well as younger patients," write researcher Hyman B. Muss, MD, of the Vermont Cancer Center in Burlington, Vt., and colleagues. "A sobering finding from this analysis is the observation that only 8 percent of patients entered in the trials analyzed in this study were aged 65 years or older; about 50 percent of new breast cancer diagnoses occur in women in the older age group."

In an editorial that accompanies the study, William J. Gradishar, MD, and Virginia G. Kaklamani, MD, DSc, of the Feinberg School of Medicine at Northwestern University, say it’s clear that adding chemotherapy after surgery in the treatment of early-stage breast cancer clearly reduces the risk of disease relapse and breast cancer death.

But they say very few older women have been included in clinical trials of chemotherapy as a secondary breast cancer treatment, and this lack of data is the result of “physician bias based on the notion that older patients will not benefit from [secondary] chemotherapy, will not tolerate it as well as younger patients, or both.”

The editorialists say it will be up to the doctor, in consultation with the patient and family, to discuss the potential benefits and risks of secondary chemotherapy in breast cancer treatment in older women, a group for whom “both the length and quality of life can be threatened by a variety of other issues.”

By Jennifer Warner, reviewed by Brunilda Nazario, MD

SOURCE: Muss, H. The Journal of the American Medical Association, March 2, 2005; vol 293: pp 1073-1081.