Femara Prevents Breast Cancer Recurrence Years after ...

[Joan M]

Starting treatment with Femara (letrozole) anywhere from one to seven years after finishing tamoxifen therapy may reduce the risk of breast cancer recurrence, according to a new analysis released on March 10 in the Journal of Clinical Oncology. Investigators say the trial hints that it may never be too late for survivors to do more to protect themselves against breast cancer recurrence.

The landmark MA-17 trial, led by the National Cancer Institute of Canada Clinical Trials Group compared placebo to Femara for five years in women who had already completed five years of tamoxifen, and when positive results were announced, patients assigned to the placebo arm were allowed to cross over and take Femara. An updated analysis of this trial evaluated a subset of women in the original placebo group who elected to cross over and compared them to women who did not, and found that women who started Femara even several years after completing the recommended five years of tamoxifen reduced their risk of recurrence by 63 percent compared with those who did not take Femara. In addition, the risk of cancer spreading to other areas of the body was reduced by 61 percent—or an absolute difference of 4 percent. The median period before starting Femara was 31 months and the range was 1.1 to 7.1 years.

More than 50 percent of breast cancer recurrences and deaths occur five or more years after completing tamoxifen treatment, consistent with the slow natural history of hormone-responsive, early-stage breast cancer, where the risk of recurrence can persist for decades. Femara is the only drug in the aromatase inhibitor class (a type of hormonal treatment for postmenopausal patients) with data showing the potential to reduce the risk of breast cancer returning when started several years after treatment with tamoxifen.

Many breast cancers remain hormone dependent, said study authors, and recurrence risk can be decreased with use of aromatase inhibitors. They caution, however, that each case is different. “Whether it is reasonable for an individual woman to take letrozole after she has been off of adjuvant tamoxifen for more than three months depends on several factors; namely, her risk of developing recurrence,” the authors wrote. They noted the risk of side effects, specifically bone breakdown, should also be considered.

The most common side effects of Femara include hot flushes, fatigue, joint pain, and nausea. Other rare, but potentially serious side effects include leukopenia (low white blood count), cataract, and pulmonary embolism.

To read the analysis in the Journal of Clinical Oncology, go to http://jco.ascopubs.org/cgi/content/full/26/12/1956.

[Alyce]

Hi Joan-
I finished Chemo April 15, started radiation this week and herceptin to continue for remainder of the year. My oncologist is going to start me on Femara in 3 weeks. I was surprised as I thought that I would be finishing herceptin first before next step of aromarase inhibitor.
I am HER2 positive, clear margins after surgery, 3 nodes removed, benign.
I am still quite tired and have some numbness in one foot. With radiation and starting femara I am a little discouraged about the next set of side effects. How did you deal with your joint pain from femara? I forgot how long you have been on it. Have you gotten your energy back?
Alyce

[Joan M]

Hi Alyce, Unfortunately (and I emphasize that), I was ER-, so I've never taken an estrogen blocker, or inhibitor. However, many of the women on this site take Femara and I'm sure they can give you some insight. Good luck with the rest of your treatment. I think the worst of it is behind you. Best, Joan

[harrie]

Joan, thank you for the info on Femara. I recently switched from Arimidex to Femara.
Maryanne