Are you having back pain with any of the following?

  • Severe pain, weakness or tingling in your leg(s).
  • Difficulty stopping urination or loss of control of bladder or bowels.
  • Unexplained fever, nausea or vomiting.
  • A history of cancer or unexplained weight loss.

We understand that you are experiencing one or more of the health issues that might be impacting your back pain.

We recommend that you discuss these health issues with your doctor before proceeding with this program.

Once you are cleared by your doctor to do this program, we hope it helps you find relief from your back pain.

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Santa Clara Medical Center

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Dr. Pan and Dr. Lee's Blog

Breast Cancer Relapse And Side Effects Related To Treatment With Arimidex

Jul 01, 2010

More than a decade ago, Tamoxifen used to be only drug for women with breast cancer that is positive for hormone receptors. 

Aromatase inhibitor

Many women are now taking a class of drug called aromatase inhibitor. There are three aromatase inhibitors: Arimidex (anastrozole), Femara (letrozole), and Aromasin (exemestane). These three drugs block estrogen from being made in the body and by doing so, block breast cancer cells from growing and spreading. They are a class of very effective drugs, reducing breast cancer relapse by 40-50% in postmenopausal women. 


The first trial that showed aromatase inhibitor as being effective in preventing breast cancer relapse was called the ATAC trial. Arimidex was the aromatase inhibitor used in this trial. Like Tamoxifen, Arimidex can cause hot flashes. Arimidex  can also cause joint pain in more than 10% of women. 

Impact of side effect to relapse

When researchers went back to analyze the data from this trial, they found that women who developed symptoms of joint pain or hot flashes from Arimidex had a 11.4% lower risk of breast cancer relapse compared to women who did not have these symptoms. This was after nine years of follow-up. For women had just joint pain but without hot flashes, the rate of relapse was 10% lower compared to women without joint pain. For women who had just hot flashes at three months after they started taking the drug, the relapse rate was 6% lower compared to women who did not have hot flashes.

This finding suggested that women who developed these side effects benefit more from the treatment. The exact reason why there is such an association is not clear. This also suggests that women should not stop the aromatase inhibitor they are taking if they develop these symptoms, and find ways to minimize the symptoms, such as by exercising, taking non-steroidal anti-inflammatory drugs, or other ways.

Additional References:

Destination health: Stopping cancer before it starts

Focus on cancer prevention, screening, treatment, and research

2019 "Eat Well, Heal Well Live Well" Resources and Educational Session Links

Resources and educational links for our 2019 Seeds of Hope.

2018 Healthy Body, Healthy Mind Resources and Educational Session Links

Resources and educational links for our 2018 Seeds of Hope.

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