Letrozole and checking estrogen levels
I have been taking Letrozole for 6 months. Is there a test (ideally a test that is sensitive and can indicate if the AI is actually working) that can check my estrogen levels? The only Estradiol test I have had was one that was checked just to confirm "menopausal status" a few months after removal of ovaries. However, this test was not very sensitive as it was not sent to a special lab and the results were received in just a few hours. I would have anticipated a lower number, but my Oncologist indicated that it was not a very sensitive assay. I would just like another potential test option that is more sensitive/comprehensive if possible.
Thank you for any thoughts!
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Hi….I wondered the same thing about the full dose vs a smaller dose. I’ve looked up some studies that show taking Letrozole every other day is pretty much the same and helps reduce the toxicity of side effects. There are some women already doing this with the blessings of their oncos. The latest article was in Pubnet. Planning on asking to go that route.
@windyshores Thanks for the response. You make a good common sense point about the side effects being caused by the result rather than the med. None is none as far as estrogen is concerned. I see another comment after this about the reduced dose causing less side effects so I guess I need to do some research. Like your earlier comment though, it would probably make me nervous to reduce the dose. If it ain’t broke don’t fix it.
@mandy75 I would love to see any studies. My doc told me I could alternate days but I never did. I totally believe effectiveness is the same (given that 20% is effective and half life allows for that in the day not taken). But I would like to see a study showing that side effects are less.
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4740217/
There are more studies out there that I’ve read. I’ve just googled Letrozole every other day and lost myself in the rabbit hole. This will be my next discussion with onco. Hope this helps!
I take 200 mg. I also take 250 mg of grape seed extract.
@mandy75 if you read the study, it says that effectiveness between 1mg and 2.5mg w/different dosing intervals was (mostly similar) but so were the side effects. Which makes sense to me. That is why I continued on the daily dose for 5 years.
From the study you linked: on side effects/Q of L
"The results of the quality-of-life responses at the end of letrozole intervention are summarized in Table 4. For the mental and physical domains of the SF-36 tool, no differences were observed in the proportion of women who experienced worsened, stable, and improved QoL scores among the treatment groups. For MENQOL assessment, the majority of study participants did not experience a clinically meaningful change in the QoL scores within the psychosocial, physical, or sexual domains. No differences were observed in the proportion of women who had worsened, stable, or improved QoL scores among the dose groups for each domain assessed in MENQOL.?
ps on effectiveness:
"In this double-blind, randomized clinical trial of high-risk postmenopausal women, effective estrogen suppression was demonstrated across all dosing regimens of letrozole: 2.5 mg daily, 2.5 mg Q-MWF, 1 mg Q-MWF, 0.25 mg Q-MWF. Following 24 weeks of treatment, estrogen suppression averaging between 75 – 78% and 86 – 93% from baseline, was observed for serum E2 and E1 levels, respectively. The extent of estrogen suppression with low and intermittent letrozole doses was non-inferior to the standard daily dose. Estrogen suppression in the standard dose arm was observed six weeks following drug discontinuation, with E2 and E1 levels suppressed by 29% and 40% from baseline, respectively. The recuperation of estrogen levels 6 weeks after letrozole discontinuation occurred in all treatment arms with a trend favoring dose-dependency."
Hi ssalget:
As your post is from Oct. 2022, were you able to get an Integrative Oncologist? Would they be in place of a Medical Oncologist?
How are your bones and have you started an AI at any point?
What are you doing for bone health?
I have not yet found an Integrative Oncologist. I'm hoping to change my PCP to a doctor at University of Washington Medical that is interested in Integrative Medicine. My current understanding is that a Medical Oncologist will offer help with natural solutions for side effects from the medications. I need to find a practitioner who will take my insurance. I am on Social Security and have a limited income. I have chosen not to take an AI and, after a year, my hands and body are no longer in pain. I am using a number of online breast cancer coaches. Using the supplements I can afford. Eating whole foods, which I did before cancer. Walking. My Medical Oncologist will still see me once a year for screening palpation. I am due for a bone density test this year. I was diagnosed with osteopenia in 2021. I had a heart attack that led to my cancer diagnosis and am leary of taking an AI for that reason, as well. My cardiologist has left U of W medical and I have not been able to get an appointment with a new provider. All in all I am doing well and getting on with living. Working on clearing some emotional trauma and working on forgiveness, staying positive and grateful.
You sound like you are organized and doing everything that you can to carry on, heal mind, body, and spirit, and go forward.
My medical oncologist cleared all the herbal and other remedies that I was taking and allowed me to continue my asking all except vitamin C during radiation. I could start it again after.
If you wish, you could tell your medical oncologist what you are taking even though you see once a year and they will reply.
Really important to get a cardiologist lined up.
Ask your primary doctor for a list of cardiologists he recommends who are taking patients or get a list from your insurance company.
I agree! How do they know it works if it can’t it be measured?