Extending Aromatase Inhibitor Treatment Time

Hester Hill Schnipper, LICSW, OSW-C Program Manager, Oncology Social Work

JANUARY 10, 2018

First a reminder: After this posting, I will not be back on this blog until January 29th. I will try then to include a picture from our Antarctica adventure. I am very excited and a bit nervous about the Drake Passage crossing.Per my entry earlier this week, however, I am filled with determination to see as much of this gorgeous world as possible, and this very southern part is said to be other-worldly beautiful.

Today, still based in Boston, I am writing about new studies related to the optimal length of time for women with ER positive breast cancers to stay on AIs (aromatase inhibitors). As you may know, the original  treatment was five years after completing chemotherapy or other initial breast cancer treatment. Since it had been learned that continuing Tamoxifen for a total of ten years, rather than the original five, reduced the recurrence and death rates, the question was whether something similar would be found with extending the duration of AI treatment.

It turns out that the answer is no. Or a qualified no as increasing the time by two years was helpful, while extending it to five years was no better than two. Summary: a total of 7 years may become the new standard. Here is a good summary and explanation from BreastCancer.org:  


Extending Aromatase Inhibitor Treatment for 5 More Years No Better Than 2 More Years 

After surgery, women diagnosed with hormonereceptorpositive breast cancer usually take hormonal therapy medicine to reduce the risk of the cancer coming back (recurrence). Hormonal therapy given after surgery is called adjuvant hormonal therapy. Hormonal therapy medicines work in two ways:

  • by lowering the amount of estrogen in the body
  • by blocking the action of estrogen on breast cancer cells

There are several types of hormonal therapy medicines. Tamoxifen, a selective estrogen receptor modulator (SERM), is one of the most wellknown.

  • Tamoxifen can be used to treat both premenopausal and postmenopausal women. The aromatase inhibitors:
  • Arimidex (chemical name: anastrozole)
  • Aromasin (chemical name: exemestane)
  • Femara (chemical name: letrozole)

have been shown to be more effective at reducing recurrence risk in postmenopausal women and are used more often than tamoxifen to treat women who’ve gone through menopause. Aromatase inhibitors aren’t commonly used to reduce recurrence risk in premenopausal women

Read more: http://www.breastcancer.org/research-news/5-more-years-of-ais-no-better-than-2-more