Five more years: Women face a difficult choice on extending hormonal therapy

Margaret Andrews couldn’t wait to be done with hormonal therapy: treatment for hormone receptor-positive breast cancer, which grows because of the hormones estrogen or progesterone. After a stage IIb breast cancer diagnosis in 1999, Margaret had surgery, chemotherapy and radiation therapy. She then began taking tamoxifen before switching to an aromatase inhibitor (AI). She thought she would be on the AI anastrozole (Arimidex) for 5 years, which quickly began to feel like a very long time.

“I was tired of hot flashes. I was tired of being tired. I was tired of muscle aches and sexual side effects,” says Margaret, 70, a retired teacher who lives in Hollis, Alaska.

At her checkup in 2007, Margaret received some unexpected news: The oncologist recommended she take anastrozole for another 5 years. That was an unusual suggestion then, but early research was beginning to suggest women with hormone receptor-positive breast cancer might receive more protection from a new breast cancer or cancer coming back if they took hormonal therapy beyond the usual 5 years. Margaret says she and her husband “were so disappointed because we were looking forward to the time when I could be off it.” But she decided to continue hormonal therapy.

Many women with hormone receptor-positive, early-stage breast cancer face the same choice Margaret did. Recent studies show a benefit to taking 10 years of hormonal therapy — tamoxifen, an aromatase inhibitor or some combination of the two — rather than 5. Premenopausal or postmenopausal women can take tamoxifen. Aromatase inhibitors are for women who are postmenopausal, naturally or after surgery or medicine that stops their ovaries from making eggs. Hormonal therapy lowers estrogen levels or changes the way the body reacts to estrogen.

The research

In 2012, the ATLAS study found women who took 10 years of tamoxifen had a lower risk of cancer coming back and a lower risk of dying from breast cancer than women who stopped the treatment after 5 years. Ten years of tamoxifen is now standard.

The latest evidence on the benefits of extending AI therapy comes from a study published in June in the New England Journal of Medicine. It found women who took 5 more years of an AI had a 34 percent lower risk of cancer returning in the same breast than those who took 5 years of an AI followed by a placebo (an inactive substance). The risk of new cancer in the other breast was also lower in the group that took 10 years of an AI.

Women in both groups were likely to be cancer free at 5 years of follow-up: 95 percent of women who took 5 more years of an AI compared to 91 percent of those in the placebo group. Taking an AI longer did not lower the risk of distant recurrence, when the cancer spreads outside the breast and nearby lymph nodes. Distant recurrence is what most affects how long a person lives. The number of deaths was low, but not different, between the two groups. It is possible more time needs to pass to see a survival difference. Quality of life was high in both groups. Those who took an AI longer coped with side effects well, but they had more bone fractures than the other group.

Kathrin Strasser-Weippl, MD, an oncologist at Wilhelminen Hospital, in Vienna, Austria, was a researcher on the study, called MA.17R. She believes the findings may cause doctors to routinely recommend 10 years of AI therapy, just like they do with tamoxifen. But that remains to be seen.

A tough choice

After so much treatment, you might feel upset to learn 10 years of a daily pill is in your future. Research shows some women have trouble staying on hormonal therapy for even a year or two. Others decide not to take it at all. Side effects that can get in the way of everyday living are a common worry. Not all women experience them, but possible side effects include:

• Bone and joint pain, and thinning bones
• Hot flashes and night sweats
• Mood changes
• Fatigue and trouble sleeping
• Thinning hair
• Loss of sexual desire and discomfort during sex because of vaginal dryness

Cost of the medicine or trouble getting into a daily pill-taking routine also may prevent you from taking years of hormonal therapy.

Katharine Campbell, PhD, LCSW, counsels people who have had breast cancer in a private practice in Wilton Manors, Florida. Some women are reluctant to talk with their doctor or loved ones about their hormonal therapy concerns, she says. Support groups or counseling can help.

Some women don’t want to take the medicine because they think of it as “putting another chemical in my body,” Dr. Campbell says. For others, “A pill can be a daily reminder of the challenges they face and that cancer has been and will be a part of their lives.” Dr. Campbell avoids talking about “right” or “wrong” decisions on continuing hormonal therapy and encourages women to talk about any tough emotions brought on by the decision.

What oncologists say

You have a choice on continuing hormonal therapy. You and your doctor should consider:

• Your individual risk of a cancer recurrence based on your initial diagnosis
• How well you cope with side effects

George W. Sledge, Jr., MD, is professor of medicine and chief of oncology at Stanford University Medical Center, in California. About half the postmenopausal women he sees with hormone receptor-positive breast cancer choose to continue taking an AI beyond 5 years. He says it is important for both doctors and women to have realistic expectations of extending AI therapy.

“If the purpose of doing 10 years versus 5 years is to live longer, then it fails that test,” he says.

Ann Partridge, MD, MPH, is a breast cancer oncologist and director of adult survivorship at Dana Farber Cancer Institute, in Boston. She says the new AI study provides some added insight for doctors and women as they decide on length of hormonal therapy.

“Is 10 years of AI therapy better than 5 years?” Dr. Partridge says. “The answer is yes, to a relatively small degree.”

Dr. Partridge understands 10 years may seem like a long time, especially if you have bad side effects. It can also be a long commitment if you are a young woman who wants to get pregnant — something you shouldn’t do while on hormonal therapy because  of risk to the fetus.

Dr. Partridge says you may be able to stop hormonal therapy for a time to have a baby and then resume the medicine, under your doctor’s guidance. Research is ongoing. She is involved in a clinical trial, called POSITIVE, studying whether doing so puts women at higher risk for breast cancer returning.

Making a decision

Wanda Johnson, 60, of Houston, Texas, was diagnosed with stage II breast cancer in 2009. Her doctor mentioned the possibility of 5 more years of treatment as her expected end date on anastrozole approached.

“I made the decision to continue this medication as long as it doesn’t present any adverse side effects for me,” says Wanda, project coordinator for Reconstruction of a Survivor, an organization that provides support groups for people who have had breast cancer.