For decades, it's been prescribed to help women fight breast cancer from coming back. Now a new study shows staying on the drug longer may not have the effects doctors once believed.
Carol Yancey's routine every morning for four years was to take Tamoxifen.
"I had a lumpectomy," explains breast cancer survivor Carol Yancey.
Tamoxifen is helping her reduce the risk of breast cancer recurrence. It's normally a five year treatment.
"For the last couple of decades, we have been using five years as our standard," explains Dr. C. Kent Osborne, MD, of the Baylor College of Medicine.
The belief was the benefit of staying on it longer was outweighed by a woman's risk, of things like uterine cancer and blood clots.
"I think this study goes a long way to show that actually doesn't seem to be the case," says Steven Isakoff, MD, PhD, from the Massachusetts General Hospital Center.
Presented at the recent breast cancer symposium, the Atlas Study, involved more than 6,800 women with ER-positive breast cancer, who would been on Tamoxifen for five years.
Some were randomly assigned to stay on the drug for five more years.
The results found the women on Tamoxifen for ten years had their risk of recurrence cut by 25 percent. Their risk of dying from breast cancer also went down 29 percent.
"I guess I'm a little bit surprised at the findings," says Dr. Osborne.
Doctors warn extending Tamoxifen is not right for all patients.
"For someone who has a generally low risk of recurrence, we will have to weigh the risks and benefits," says Dr. Isakoff.
Now, the challenge could be spreading the word.
"I think it will just naturally find its spot in the treatment," says Dr. Osborne.
If Carol's doctor says this will continue to be her daily routine for six more years, instead of one more year then; "I would do it, if it means that this doesn't come back, and I don't have to go through any of that again."
The Atlas Study found ten years of Tamoxifen does have some side effects, the biggest, being, the risk of endometrial cancer. Because it's generally curable, researchers say that risk is heavily outweighed by the possible benefits of extending the drug treatment.
The Atlas Study: A big change in breast cancer treatment
BREAST CANCER: Over the course of a lifetime, one in eight women will be diagnosed with breast cancer. Breast cancer typically starts in the tissues of the breast; however, on rare occasions it can start in other areas. There are two main types of breast cancer:
* Ductal carcinoma starts in the tubes (ducts) that move milk from the breast to the nipple. Most breast cancers are of this type.
* Lobular carcinoma starts in the parts of the breast, called lobules; that produce milk.
RISK FACTORS: There are several risk factors for breast cancer - some that cannot be changed-such as age or gender, or if there is family history of breast cancer, but there are other contributing factors, which can be avoided, such as drinking alcohol. Drinking more than one or two glasses of alcohol a day increases the risk of breast cancer. (SOURCE: http://www.ncbi.nlm.nih.gov/pubmedhealth)
SYMPTOMS: Early breast cancer usually does not cause symptoms. This is why regular breast exams are important. As the cancer grows, symptoms may include:
* Finding a lump(s) in the armpit that are hard and have uneven edges.
* Fluid coming from the nipple -- may be bloody, clear to yellow, green, and look like pus.
* Men can get breast cancer, too. Symptoms include breast lump and breast pain and tenderness.
TREATMENT: Since its approval in 1998, tamoxifen has been used to treat millions of women and men diagnosed with hormone-receptor-positive breast cancer. Tamoxifen can:
* Reduce the risk of breast cancer coming back by 40% to 50% in postmenopausal women and by 30% to 50% in premenopausal women.
* Lower the risk of a new cancer developing in the other breast by about 50%.
* Slow or stop the growth or advanced (metastatic) hormone-receptor-positive breast cancer in both pre- and postmenopausal women.
THINGS YOU DIDN'T KNOW: Tamoxifen is also used sometimes to induce ovulation (egg production) in women who do not produce eggs, but wish to become pregnant. It can be used to treat McCune-Albright syndrome (a condition that may cause bone disease, early sexual development, and dark colored spots on the skin in children). (www.nlm.nih.gov/medlineplus/druginfo/meds)
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