Femara for Breast Cancer: October News and Research

October has been hopping with news and research about the aromatase inhibitor Femara (letrozole) for breast cancer. Today we'll share the five latest studies and the headlines about them. Links may be found on the Femara (letrozole) page of our website.

Femara more effective than tamoxifen

The big story this month was an October 21 study in The Lancet Oncology which compared 8 year recurrence and survival rates for postmenopausal women taking Femara, tamoxifen or a sequential combination of both for early-stage, hormone-receptor positive breast cancer. The study is known as the Breast International Group (BIG) 1-98 study. The New York Times, The Telegraph (UK), US News and World Report/HealthDay and Medical News Today all ran stories.

According to the study, Femara alone resulted in a reduction in breast cancer recurrence and death compared to tamoxifen alone. Sequential use of tamoxifen and Femara, in any order, did not improve outcome compared to Femara alone, "but might be useful strategies when considering an individual patient's risk of recurrence and treatment tolerability."

Femara improves response to chemotherapy before surgery

Not all of the October Femara studies made headlines. An October 16 study in Breast Cancer Research and Treatment evaluated the addition of Femara to chemotherapy before surgery for postmenopausal women with locally advanced breast cancer. For women with hormone-receptor positive breast cancer, the addition of Femara to chemotherapy improved clinical and pathological response rates with "acceptable toxicity" compared to chemotherapy alone.

Femara reduces bone mineral density

Not all Femara news this month was good. An October 14 Annals of Oncology study evaluated bone loss in women in the BIG 1-98 study discussed above. It found that Femara use was associated with a reduction in bone mineral density, whether used alone or in sequence with tamoxifen, when compared to the use of tamoxifen alone. In fact, the "sequential schedules were as detrimental for bone density" as taking Femara alone.

Zometa improves bone mineral density for women taking Femara

There may be a way to reduce the risk of bone loss associated with Femara. An October 10 study in the journal Cancer compared the immediate use of Zometa (zoledronic acid) with the delayed use in postmenopausal women with early breast cancer taking Femara for 5 years. The trial is known as Z-FAST. The Los Angeles Times and Medical News Today covered the study.

According to the study, taking Zometa (zoledronic acid) with Femara "upfront," from the beginning, "significantly and progressively" increases bone mineral density, compared with a delayed start of Zometa. The authors also found that "long-term coadministration of letrozole and zoledronic acid is well tolerated."

Another study evaluated the data from the Z-FAST trial. Whereas the October 10 Cancer study looked at bone mineral density at 5 years, an October 17 study in Clinical Breast Cancer evaluated the data at month 12. It also found that immediate use of Zometa prevented bone loss and increased bone mineral density, "regardless of BMD [bone mineral density] at baseline."

These are only the five most recent studies on Femara (letrozole) for breast cancer. For two years of news and research, plus overviews and FDA information, please check the Femara (letrozole) page of our LATESTBreastCancer.com website. From the home page, click the Treatments tab and search for 'Femara' in the search box on the top right of the page.

We'll continue to follow developments in breast cancer research. Links are added to our website daily and interesting findings are highlighted here. Please stay tuned.

Zometa for Early-Stage Breast Cancer: Hormones May Matter

Can Zometa (zoledronic acid) prevent recurrence in women with early-stage breast cancer? Today we'll share the latest news and research. Links may be found on the Zometa (zoledronic acid) page of our website.

A new role for Zometa

Zometa is a bisphosphonate often prescribed to prevent bone loss in women taking aromatase inhibitors for breast cancer. It's also used to treat bone metastases in women with stage IV breast cancer.

Recent studies suggest Zometa may also prevent recurrence in women with early-stage breast cancer, but the results have been inconsistent. A new study in the New England Journal of Medicine suggests the key may lie in the hormonal status of the patient.

June: Zometa benefits premenopausal women on Zoladex and hormone therapy

A June 3 study in The Lancet Oncology evaluated Zometa in premenopausal women with hormone-receptor positive, stage I or II breast cancer, who were taking Zoladex (goserelin) for ovarian supression. (Drugs.com covered the study on June 3.)

About half of the 1,803 women took Zometa plus tamoxifen or Arimidex (anastrozole). The rest took tamoxifen or Arimidex alone.

At about 5 years follow-up, more than 2 years after completion of treatment with Zometa, 8% (76/900) of the Zometa group experienced a recurrence, compared to 12% (110/903) of the tamoxifen or Arimidex alone group. There was no significant difference in overall survival. (30 deaths out of 900 women taking Zometa, 43 out of 903 not taking Zometa.)

The authors concluded that the addition of Zometa "improved disease-free survival in the patients taking anastrozole or tamoxifen." They added, "These data show persistent benefits with zoledronic acid and support its addition to adjuvant endocrine therapy in premenopausal patients with early-stage breast cancer."

September: Zometa may only benefit postmenopausal women

In a September 25 New England Journal of Medicine study, about half of the 3,360 women with early-stage breast cancer were treated with Zometa plus standard chemo and hormone therapy. The rest received standard therapy alone. Patients varied in age, menopausal and hormone-receptor status.

In contrast to the Lancet study, at 5 years follow-up, the New England Journal of Medicine study found "no improvement" in disease-free survival for women with early-stage breast cancer taking Zometa. The authors concluded that their findings, "do not support the routine use of zoledronic acid as adjuvant therapy in unselected patients with early-stage breast cancer."

However, when the study participants were evaluated by subgroup, Zometa seemed to benefit postmenopausal women. (Reuters and Medical News Today covered this aspect of the study on September 25.) Zometa improved both disease-free survival (recurrence) rates and overall survival (death) rates for the group who had undergone menopause more than 5 years earlier.

The authors concluded, "For postmenopausal women, the use of bisphosphonates remains appropriate for the prevention of treatment-induced bone loss and osteoporosis and might have beneficial effects on disease outcomes. The optimum schedule, duration, and type of bisphosphonate therapy remain unknown."

Hormonal status may be the key

How do we reconcile these two studies? One found a benefit for premenopausal patients, the other did not. The answer may lie in the hormonal status of the patients.

The New England Journal of Medicine study noted that from a hormonal perspective, the postmenopausal patients in its study were similar to the premenopausal patients in the Lancet study who were treated with Zoladex for ovarian suppression. Both groups "had low levels of reproductive hormones at study entry." The authors suggest that Zometa "operates differently according to menopausal status."

Finally, the authors note that even though chemotherapy may induce menopause in young women, complete ovarian suppression may take "many months." They conclude, "Further investigation into the possible interaction between zoledronic acid and reproductive hormones is required."

At LATESTBreastCancer.com, we'll continue to follow developments in research on Zometa for breast cancer. We'll keep you posted.