Aromatase Inhibitors

The standard recommendation is for five years of aromatase therapy based on our present knowledge and the results of numerous large clinical trials that compared aromatase inhibitors to tamoxifen. It is also an acceptable strategy to initiate therapy with tamoxifen and switch to an aromatase inhibitor after 2 to 3 years to complete a total of five years of therapy. Based on evidence from a large clinical trial, it is also acceptable to switch to tamoxifen from an aromatase inhibitor; this is an option for individuals who are experiencing difficult side effects with aromatase inhibitors. The standard recommendation is for five years of aromatase therapy based on our present knowledge and the results of numerous large clinical trials that compared aromatase inhibitors to tamoxifen. It is also an acceptable strategy to initiate therapy with tamoxifen and switch to an aromatase inhibitor after 2 to 3 years to complete a total of five years of therapy. Based on evidence from a large clinical trial, it is also acceptable to switch to tamoxifen from an aromatase inhibitor; this is an option for individuals who are experiencing difficult side effects with aromatase inhibitors.

This may vary depending on the individual and their risk for bone density loss or fracture. It is important when starting an aromatase inhibitor that you have a baseline bone mineral density study (referred to as a DEXA scan) and a clinical assessment for other potential risk factors for osteoporosis (defined as a T score < 2.5 on a DEXA scan by the World Health Organization). These risks include older age, previous fracture, low body weight, current tobacco use, and excessive alcohol consumption, among others. I encourage all women starting an aromatase inhibitor to adopt lifestyle changes that promote not only bone health but overall health as well. These include increasing physical activity (including weight bearing exercise), stopping smoking, and taking calcium and vitamin D supplements. Some individuals starting an aromatase inhibitor may be advised to take drug therapy with bisphosphonates if they have osteoporosis or a history of a fracture or osteopenia (http://www.medterms.com/script/main/art.asp?articlekey=8048)(T-score between -1 and -2.5 on a DEXA scan) with other risk factors. There is no consensus on the optimal strategy for monitoring but every two years is a common strategy. This may vary depending on the individual and their risk for bone density loss or fracture. It is important when starting an aromatase inhibitor that you have a baseline bone mineral density study (referred to as a DEXA scan) and a clinical assessment for other potential risk factors for osteoporosis (defined as a T score < 2.5 on a DEXA scan by the World Health Organization). These risks include older age, previous fracture, low body weight, current tobacco use, and excessive alcohol consumption, among others. I encourage all women starting an aromatase inhibitor to adopt lifestyle changes that promote not only bone health but overall health as well. These include increasing physical activity (including weight bearing exercise), stopping smoking, and taking calcium and vitamin D supplements. Some individuals starting an aromatase inhibitor may be advised to take drug therapy with bisphosphonates if they have osteoporosis or a history of a fracture or osteopenia (http://www.medterms.com/script/main/art.asp?articlekey=8048)(T-score between -1 and -2.5 on a DEXA scan) with other risk factors. There is no consensus on the optimal strategy for monitoring but every two years is a common strategy.

Aromatase inhibitors lower estrogen levels in your body and this estrogen deficiency leads to increased bone turnover and bone loss. This side effect, however, does not reflect whether the medication is working for your breast cancer. Estrogen is known to stimulate hormone receptor positive breast tumor cells and aromatase inhibitors are very effective at lowering estrogen levels and thereby removing this growth signal and resulting in tumor cell death. Thus, the lowering of estrogen is a critical reason why these drugs work so well to treat hormone receptor positive breast cancer but may have, at the same time, a negative impact on bone health. Aromatase inhibitors lower estrogen levels in your body and this estrogen deficiency leads to increased bone turnover and bone loss. This side effect, however, does not reflect whether the medication is working for your breast cancer. Estrogen is known to stimulate hormone receptor positive breast tumor cells and aromatase inhibitors are very effective at lowering estrogen levels and thereby removing this growth signal and resulting in tumor cell death. Thus, the lowering of estrogen is a critical reason why these drugs work so well to treat hormone receptor positive breast cancer but may have, at the same time, a negative impact on bone health.

Initiation of hormonal therapy is commonly begun after the completion of chemotherapy (and after completion of radiation therapy if you receive both). In terms of actual timing, hormonal therapy will typically begin approximately four to six weeks following completion of chemotherapy. A preference for sequential timing of chemotherapy and hormonal therapy, i.e., adjuvant chemotherapy followed by hormonal therapy, was suggested by a clinical trial, in which sequential versus concurrent chemo/hormonal therapy were directly compared and sequential treatment had superior outcomes for disease free and overall survival.

I would add that there are limited clinical data and no consensus on the use of concurrent hormonal therapy and radiation therapy, thus some medical oncologists advise overlap of hormonal therapy with radiation and others advise waiting until radiation is complete. I generally advise waiting until radiation is complete. Initiation of hormonal therapy is commonly begun after the completion of chemotherapy (and after completion of radiation therapy if you receive both). In terms of actual timing, hormonal therapy will typically begin approximately four to six weeks following completion of chemotherapy. A preference for sequential timing of chemotherapy and hormonal therapy, i.e., adjuvant chemotherapy followed by hormonal therapy, was suggested by a clinical trial, in which sequential versus concurrent chemo/hormonal therapy were directly compared and sequential treatment had superior outcomes for disease free and overall survival.

I would add that there are limited clinical data and no consensus on the use of concurrent hormonal therapy and radiation therapy, thus some medical oncologists advise overlap of hormonal therapy with radiation and others advise waiting until radiation is complete. I generally advise waiting until radiation is complete.

There were some early reports in the literature that soy foods may reduce the effectiveness of Tamoxifen in animal studies, but at least one study from the Univ of So Cal (wu, JCO, 2007) showed that soy food consumption had no effect on the active metabolites of Tamoxifen in Asian American breast cancer survivors. There were some early reports in the literature that soy foods may reduce the effectiveness of Tamoxifen in animal studies, but at least one study from the Univ of So Cal (wu, JCO, 2007) showed that soy food consumption had no effect on the active metabolites of Tamoxifen in Asian American breast cancer survivors.

No, I did not begin taking Tamoxifen until after my son was born. Tamoxifen is harmful to fetuses and should not be taken while pregnant. No, I did not begin taking Tamoxifen until after my son was born. Tamoxifen is harmful to fetuses and should not be taken while pregnant.

I've taken a number of aromatase inhibitors, starting with Arimidex, followed by Femera, and now Aromasin. About six months in, Arimidex starting giving me the most incredible joint pain in my feet. I tried managing the pain for another 8-12 months but feet were in so much pain and I wasn't getting any relief from anti-inflammatory meds (i.e. Aleve or Advil). I was then given Femera and felt a 100 times better physically but at the six-month mark I noticed my hair was thinning - a lot. Im honestly not sure if it was the Femera or menopause but my oncologist felt it wasn't necessary to have to deal with that issue. I just started taking Aromasin about two weeks ago and haven't noticed any uncomfortable side effects yet. My hair still seems to be thinning though. I've taken a number of aromatase inhibitors, starting with Arimidex, followed by Femera, and now Aromasin. About six months in, Arimidex starting giving me the most incredible joint pain in my feet. I tried managing the pain for another 8-12 months but feet were in so much pain and I wasn't getting any relief from anti-inflammatory meds (i.e. Aleve or Advil). I was then given Femera and felt a 100 times better physically but at the six-month mark I noticed my hair was thinning - a lot. Im honestly not sure if it was the Femera or menopause but my oncologist felt it wasn't necessary to have to deal with that issue. I just started taking Aromasin about two weeks ago and haven't noticed any uncomfortable side effects yet. My hair still seems to be thinning though.

I will not recommend, but share experience. My partner chose not to take Tamoxifen, and instead opted for use of bio-identical hormones, including 2-methoxyestadiol, progesterone, DHEA and testosterone. 2-methoxyestradiol has been shown in various studies to have cancer fighting potential, acting both as an selective estrogen receptor modulator like Tamoxifen but also anti-carcinogen. See http://lib.bioinfo.pl/pmid:15156405 as an example. Please review this option with your oncologist, hopefully an integrative one. It would be unethical for me to take someone off their medications. Often it's not an "either-or" situation (either drugs or alternatives), but a "both-and". Each has its place. Whether the ones you are on are the best for you, I can't address here, as that requires a more detailed and in-depth understanding of your health. There are many things which help the body clear excess estrogens: first, avoid exposure to them (buy safer/chemical-free home, personal care, garden and beauty products without hormone-like compounds in them); avoid any hot foods or fatty foods in plastic or styrofoam (hormone disruptors/estrogenic), as the packaging melts into the food when heated or when in contact with fats; eat only organic animal products (animals are allowed to be given estrogen, progesterone & testosterone to grow them faster and fatter. We ingest these if we eat them in meat, eggs, butter, cheese, yogurt, etc.); keep a low glycemic diet which reduces sugar and insulin in the blood, both of which are cancer growth triggers; add many of the foods I mentioned earlier; add exercise, which reduces blood sugar and has many cancer-protective/heart-healthy/spirit-lifting benefits; get sufficient sleep to help your immune and endocrine systems (melatonin, the sleep/immune hormone is made in the dark, so sleep with all lights out); b vitamins (as supplement and/or greens &/or whole grains) help the body clear estrogens; high fiber & and good liver function help the body clear estrogens; pro- & pre-biotics help the immune system (they make some of the b vitamins & vitamin k) and support digestion; and keep a calm mind/spirit, which will reduce the body's stress hormone, cortisol, production. Cortisol is a cancer growth factor. Enjoy your life and yourself as much as possible!

My partner is also premenopausal, and has refused taking Tamoxifen, despite being ER+. Instead, she has opted for use of bio-identical hormones. 2-methoxyestradiol has been demonstrated to have the SERM like qualities of Tamoxifen, however, with no side effects. In addition, it has specific anti-cancer properties. We reference http://lib.bioinfo.pl/pmid:15156405 as one study among many. Good luck with your choice! I didn't tolerate Tamoxifen either and I am premenopausal. My doctor suggested ovarian supression with Lupron injections or having the ovaries removed. I have not done either because my gyn. suggests this can cause problems with bone and heart health in young women who still need some levels of estrogen. My oncologist told me that in my particular case, being heavily her2+++, that Tamoxifen offered me about only a 3% reduction in recurrence and that the her2+ was my larger risk factor. I have decided to not look back and stop obsessing about it all. I have had chemo and mastectomy.

There is a small numerical advantage, on average, associated with the use of aromatase inhibitors over tamoxifen. However, that does not mean that every single patient must use the AIs. If the AIs are intolerable it is reasonable to use tamoxifen instead. There is a small numerical advantage, on average, associated with the use of aromatase inhibitors over tamoxifen. However, that does not mean that every single patient must use the AIs. If the AIs are intolerable it is reasonable to use tamoxifen instead.

Both you and your physician will be monitoring the potential risks of letrozole.

The risks that may cause the most concern are:
- Decreases in bone mineral density (BMD).
- Increases in cholesterol.

The patient should be aware and notify the physician of any changes in how they feel, particularly paying attention to bone pain and liver pain (upper right quadrant).

The way to monitor these risks are through the following:
- bone density test
- complete blood cell counts (CBC)
- thyroid function tests
- monitoring serum electrolytes
- monitoring cholesterol and liver function tests, kidney function, and blood pressure.

There will also be the physical assessment of the patient. This will include blood pressure readings, pain assessment, gastrointestinal upsets, and hot flashes.

When initiating letrozole treatment, patients may experience dizziness and fatigue. Until your body adjusts be cautious before performing work that requires mental alertness, such as driving.

For more information, see the follwing links:

http://www.rxlist.com/femara-drug.htm
http://www.webmd.com/drugs/drug-4363-Femara+Oral.aspx?drugid=4363&drugname=Femara+Oral Both you and your physician will be monitoring the potential risks of letrozole.

The risks that may cause the most concern are:
- Decreases in bone mineral density (BMD).
- Increases in cholesterol.

The patient should be aware and notify the physician of any changes in how they feel, particularly paying attention to bone pain and liver pain (upper right quadrant).

The way to monitor these risks are through the following:
- bone density test
- complete blood cell counts (CBC)
- thyroid function tests
- monitoring serum electrolytes
- monitoring cholesterol and liver function tests, kidney function, and blood pressure.

There will also be the physical assessment of the patient. This will include blood pressure readings, pain assessment, gastrointestinal upsets, and hot flashes.

When initiating letrozole treatment, patients may experience dizziness and fatigue. Until your body adjusts be cautious before performing work that requires mental alertness, such as driving.

For more information, see the follwing links:

http://www.rxlist.com/femara-drug.htm
http://www.webmd.com/drugs/drug-4363-Femara+Oral.aspx?drugid=4363&drugname=Femara+Oral

Anastrozole is indicated for:
- Treatment of hormone receptor-positive early and metastatic breast cancer in post-menopausal women. It may be used alone or after surgery or radiation. (Early breast cancer is cancer that has not spread outside the breast to other parts of the body.)
- Treatment of hormone receptor-positive breast cancer that has progressed after receiving tamoxifen treatment for post-menopausal women.
- Post-menopausal women where the ER-positive or hormone receptor unknown breast cancer has spread in the breast or to other parts of the body.

For more information, see the following link:
http://www.ncbi.nlm.nih.gov/pubmedhealth/PMH0000982/ Anastrozole is indicated for:
- Treatment of hormone receptor-positive early and metastatic breast cancer in post-menopausal women. It may be used alone or after surgery or radiation. (Early breast cancer is cancer that has not spread outside the breast to other parts of the body.)
- Treatment of hormone receptor-positive breast cancer that has progressed after receiving tamoxifen treatment for post-menopausal women.
- Post-menopausal women where the ER-positive or hormone receptor unknown breast cancer has spread in the breast or to other parts of the body.

For more information, see the following link:
http://www.ncbi.nlm.nih.gov/pubmedhealth/PMH0000982/

There is no dosage adjustment of letrozole for patients with normal kidney and liver function. The physician will monitor for kidney and liver function using kidney and liver function tests and change medications if needed.

- With mild to moderate impairment of the liver, the dose of letrozole will not be changed.
- For post menopausal women taking Letrozole with liver problems (cirrhosis and severe hepatic impairment), as determined by liver function tests, the dose recommended for this patient population is 2.5mg every other day.
- There is no change in dosage requirements for patients with a creatinine clearance of the kidneys greater than or equal to 10ml/min.

For more information on this subject, see the following links:
http://www.rxlist.com/femara-drug.htm
http://www.drugs.com/dosage/letrozole.html There is no dosage adjustment of letrozole for patients with normal kidney and liver function. The physician will monitor for kidney and liver function using kidney and liver function tests and change medications if needed.

- With mild to moderate impairment of the liver, the dose of letrozole will not be changed.
- For post menopausal women taking Letrozole with liver problems (cirrhosis and severe hepatic impairment), as determined by liver function tests, the dose recommended for this patient population is 2.5mg every other day.
- There is no change in dosage requirements for patients with a creatinine clearance of the kidneys greater than or equal to 10ml/min.

For more information on this subject, see the following links:
http://www.rxlist.com/femara-drug.htm
http://www.drugs.com/dosage/letrozole.html

Letrozole (Femara) may be employed for breast cancer in these circumstances:
- Early adjuvant treatment for hormone receptor positive (HR+) breast cancer in post-menopausal women. It is unknown how long letrozole should be taken, but the duration of the clinical trial was 5 years. Adjuvant treatment is the administration of letrozole after surgery, radiation, and/or chemotherapy.
- Extended adjuvant treatment for hormone receptor positive (HR+) breast cancer in postmenopausal women who have received 5 years of adjuvant tamoxifen treatment. The ideal length of treatment is not known, as the international study of 5,187 postmenopausal women discovered that when letrozole was taken after completing five years of tamoxifen therapy, there was a decrease in breast cancer recurrences. Treatment may be discontinued if there is a relapse.
- As first or second-line treatment of breast cancer that has advanced in menopausal women after anti-estrogen treatment. Administration may be continued until the breast cancer tumor worsens or metastasizes.
- Locally advanced or metastasized breast cancer with hormone receptor positive or unknown hormone origin.

Here are a couple of other sites to visit for more information.
http://www.ncbi.nlm.nih.gov/pubmed/15161328
http://www.cancer.gov/cancertopics/druginfo/letrozole Letrozole (Femara) may be employed for breast cancer in these circumstances:
- Early adjuvant treatment for hormone receptor positive (HR+) breast cancer in post-menopausal women. It is unknown how long letrozole should be taken, but the duration of the clinical trial was 5 years. Adjuvant treatment is the administration of letrozole after surgery, radiation, and/or chemotherapy.
- Extended adjuvant treatment for hormone receptor positive (HR+) breast cancer in postmenopausal women who have received 5 years of adjuvant tamoxifen treatment. The ideal length of treatment is not known, as the international study of 5,187 postmenopausal women discovered that when letrozole was taken after completing five years of tamoxifen therapy, there was a decrease in breast cancer recurrences. Treatment may be discontinued if there is a relapse.
- As first or second-line treatment of breast cancer that has advanced in menopausal women after anti-estrogen treatment. Administration may be continued until the breast cancer tumor worsens or metastasizes.
- Locally advanced or metastasized breast cancer with hormone receptor positive or unknown hormone origin.

Here are a couple of other sites to visit for more information.
http://www.ncbi.nlm.nih.gov/pubmed/15161328
http://www.cancer.gov/cancertopics/druginfo/letrozole

We have not discussed taking Tamoxifen longer than 5 years or taking an aromatase inhibitor. I had asked him about aromatase inhibitors awhile ago and he said they don't have the clinical trial history that Tamoxifen has. I see him again next month so I may ask him whether an AI drug makes more sense now that I have officially hit menopause. I'm perfectly fine continuing on Tamoxifen though. I'm lucky to not have any side effects, and I read recently that the benefits can last up to 15 years. I just finished year three on Tamoxifen so I have another couple of years to go. We have not discussed taking Tamoxifen longer than 5 years or taking an aromatase inhibitor. I had asked him about aromatase inhibitors awhile ago and he said they don't have the clinical trial history that Tamoxifen has. I see him again next month so I may ask him whether an AI drug makes more sense now that I have officially hit menopause. I'm perfectly fine continuing on Tamoxifen though. I'm lucky to not have any side effects, and I read recently that the benefits can last up to 15 years. I just finished year three on Tamoxifen so I have another couple of years to go.

Anastrozole treats breast cancer by inhibiting the production of estrogen in tissues of the body of post-menopausal women.
- By inhibiting the production of estrogen, the estrogen receptor [ER]-positive and/or progesterone receptor [PR]-positive cancer cells cannot grow.
- Anastrozole operates by blocking the aromatase enzyme that converts androgen to estrogen in the tissues of women who have gone through menopause.
- Postmenopausal women get estrogen from the conversion of androgen into estrogen in the tissues of the body.
- In women who have not gone through menopause, they receive their estrogen from the ovaries.
- Anastrozole is categorized pharmacologically as an antineoplastic agent and as a nonsteroidal aromatase inhibitor and is indicated for postmenopausal women. Anastrozole treats breast cancer by inhibiting the production of estrogen in tissues of the body of post-menopausal women.
- By inhibiting the production of estrogen, the estrogen receptor [ER]-positive and/or progesterone receptor [PR]-positive cancer cells cannot grow.
- Anastrozole operates by blocking the aromatase enzyme that converts androgen to estrogen in the tissues of women who have gone through menopause.
- Postmenopausal women get estrogen from the conversion of androgen into estrogen in the tissues of the body.
- In women who have not gone through menopause, they receive their estrogen from the ovaries.
- Anastrozole is categorized pharmacologically as an antineoplastic agent and as a nonsteroidal aromatase inhibitor and is indicated for postmenopausal women.

Letrozole (Femara) is an antineoplastic agent. Antineoplastic agents are anticancer medications. Letrozole is also categorized as a nonsteroidal aromatase inhibitor. Aromatase inhibitors do not allow the aromatase enzyme to convert androgen into estrogen in the tissues. By blocking estrogen production in the tissues of the body, the estrogen receptor [ER]-positive and/or progesterone receptor [PR]-positive) breast cancer cells cannot grow. Letrozole (Femara) is an antineoplastic agent. Antineoplastic agents are anticancer medications. Letrozole is also categorized as a nonsteroidal aromatase inhibitor. Aromatase inhibitors do not allow the aromatase enzyme to convert androgen into estrogen in the tissues. By blocking estrogen production in the tissues of the body, the estrogen receptor [ER]-positive and/or progesterone receptor [PR]-positive) breast cancer cells cannot grow.

Seek out a naturopathic doctor within your area and inquire about Helixor or Iscador. They are both injectables which has been used with great clinical success in patients with cancer.

You could also inquire about a few herbals/neutraceuticals which can strengthen your body & decrease the side effects of the chemotherapeutics.

In terms of diet, it is important to support optimal hormone function - and yes, this can come down to bowel movements. If you do not have daily regular bowel movements, hormones that your body has metabolized sits in your colon & can be released back into your system. To avoid this, I encourage the use of professional grade probiotics, 2 TBL of freshly ground flax seeds & 1 TBL of chia seeds daily, in addition to keeping well hydrated (water, sugar-free organic coconut water instead of pop/juice) throughout the day.

Additional naturopathic alternatives should be discussed with you ND as they can tailor a protocol specific to your needs. Seek out a naturopathic doctor within your area and inquire about Helixor or Iscador. They are both injectables which has been used with great clinical success in patients with cancer.

You could also inquire about a few herbals/neutraceuticals which can strengthen your body & decrease the side effects of the chemotherapeutics.

In terms of diet, it is important to support optimal hormone function - and yes, this can come down to bowel movements. If you do not have daily regular bowel movements, hormones that your body has metabolized sits in your colon & can be released back into your system. To avoid this, I encourage the use of professional grade probiotics, 2 TBL of freshly ground flax seeds & 1 TBL of chia seeds daily, in addition to keeping well hydrated (water, sugar-free organic coconut water instead of pop/juice) throughout the day.

Additional naturopathic alternatives should be discussed with you ND as they can tailor a protocol specific to your needs.

I am on Femara. I unfortunately have other pills as well. I have them all set up in a pill container for 2 weeks at a time, I take mine at night faithfully with my other meds. I sometimes still get nauseous from Femara so this way I sleep right through it. I would suggest taking it at a time of day that you WILL remember. I find having cancer you just do NOT forget to take it for the fear of cancer returning. Oh and definitely as JK Jones stated above, take calcium and Vitamins D as well. I am on Femara. I unfortunately have other pills as well. I have them all set up in a pill container for 2 weeks at a time, I take mine at night faithfully with my other meds. I sometimes still get nauseous from Femara so this way I sleep right through it. I would suggest taking it at a time of day that you WILL remember. I find having cancer you just do NOT forget to take it for the fear of cancer returning. Oh and definitely as JK Jones stated above, take calcium and Vitamins D as well.

When initiating treatment with Letrozole, here are some topics to be aware of and inform your physician:
- What allergies you have and if you've ever experienced an allergy to Letrozole.
- Your medical history including if you have any issues with cholesterol, liver disease, bone complications, history of stroke or blood clots, heart disease, high blood pressure, or kidney issues.
- Any other medications you are taking and this includes prescription medications, all over-the-counter products you are taking, vitamins, and herbal remedies as they might contain estrogenic components or promote estrogen activity.
- Any other medications that you are taking that contain estrogen such as hormone replacement drugs or hormonal contraceptives which includes all birth control products such as contraceptive pills, patches, rings, or injections.
- If you are taking tamoxifen or raloxifene.
- Women who are perimenopausal or recently menopausal should employ contraception methods until postmenopausal status is achieved. Letrozole is harmful to the fetus.
- If you are pregnant or breast feeding. When initiating treatment with Letrozole, here are some topics to be aware of and inform your physician:
- What allergies you have and if you've ever experienced an allergy to Letrozole.
- Your medical history including if you have any issues with cholesterol, liver disease, bone complications, history of stroke or blood clots, heart disease, high blood pressure, or kidney issues.
- Any other medications you are taking and this includes prescription medications, all over-the-counter products you are taking, vitamins, and herbal remedies as they might contain estrogenic components or promote estrogen activity.
- Any other medications that you are taking that contain estrogen such as hormone replacement drugs or hormonal contraceptives which includes all birth control products such as contraceptive pills, patches, rings, or injections.
- If you are taking tamoxifen or raloxifene.
- Women who are perimenopausal or recently menopausal should employ contraception methods until postmenopausal status is achieved. Letrozole is harmful to the fetus.
- If you are pregnant or breast feeding.