premeno + tamox can lead to bone loss

peggy_j

Others mentioned this years ago and I didn't want to believe it but...after two years on tamox I'm showing bone loss. (I guess I don't have proof that it's due to the tamox, but I had met with a bone endocrinologist to review all the lifestyle factors such as diet, exercise, etc, and I've been doing the best that I can).

When I discussed this with MO prior to starting tamox, she said the bone loss was correlated with pre-meno patients who had chemo; since I didn't have chemo, my bones should be stable or improve. Wrong.

Anyone else?

peggy_j

For some reason, the oncologists have a different opinion about bone loss and SERMs than the endocrinologists. (not sure why). I asked my endocrinologist if he could suggest a research paper that I could pass along to my MO and he sent this one. (below) FYI in case it helps anyone.

FWIW, my MO says there may be a link between bone loss and  chemo but...I didn't have chemo and had significant bone loss in just 2 years on tamox.  But...I'm at high risk for osteoporisis and insisted on being monitored; I asked for a DEXA before Tx and now. I'm beginning to wonder how many pre-meno women on tamox are even being monitored. Is this being recommended for anyone or do we have to know to ask?

Anyway, here's the paper:

Management of cancer treatment-induced bone loss in early breast and prostate cancer -- a consensus paper of the Belgian Bone Club.

http://www.ncbi.nlm.nih.gov/pubmed/17690930

Depending on the tissue and prevailing estrogen levels,
tamoxifen exhibits a range of biologic activity from full
estrogen antagonism to partial agonism. Randomized
placebo-controlled trials of predominantly postmenopausal
patients have shown that adjuvant tamoxifen at a dose of 20
to 30 mg/d over 2 years is associated with an increase in
BMD in the lumbar spine [10]. Despite acting as a partial
estrogen agonist on the skeleton, tamoxifen causes bone
loss in the spine and hip in premenopausal patients,
probably because it acts as an estrogen antagonist in the
presence of premenopausal levels of estrogens. In a
placebo-controlled tamoxifen chemoprevention trial, the
mean annual loss in lumbar BMD per year over the 3-year
study period in tamoxifen-treated compliant women who
remained premenopausal throughout the study period was
1.44% compared with a small gain of 0.24% per year for
women on placebo (P<0.001). Tamoxifen had the opposite
effect in postmenopausal women, as the mean annual
increase in BMD for postmenopausal women on tamoxifen
was 1.17% in the spine (P<0.005) and 1.71% in the hip (P
<0.001) as compared with a insignificant loss in the
placebo group [11].

mdg

I was 45 at diagnosis and premenopausal. I have been a fitness professional for 25 plus years so I have always been healthy.  I am 47 now and had to have an ophorectomy because of cysts on ovaries.  My MO wanted to consider changing me from tamoxifen to an AI so he ordered a bone scan.  My T-score was -2.4!  At  -2.5 I would be considered to have osteoporosis!   I also had chemo and have not had a period since March of 2011.  Now I have been seeing an endocrinologist to build bone density. I have to take meds for that (Atelvia) now. My doc hopes to keep me on it a year and if my bones are stable I can go off it.  I am frustrated that a bone scan was not done BEFORE all of this to see if before chemo and forced menopause my levels were normal or low.  I should not have osteopenia this bad at age 47!  My endocrinologist did several tests trying to determine a cause of my severe osteopenia but all tests came back normal.  He believe it is the chemo and forced menopause.  I wish someone would have discussed that with me earlier in treatment. 

coraleliz

Good topic, for me anyway. My T score was "0" 9 months into Tamox treatment. I'll have to request that it be re-done at some point. I'm sure it won't be offered to me automatically. Was 52 when diagnosed but late menopause runs(rules) in my family

Anonymous

I pushed for a bone scan before starting Tamoxifen because I had heard it can cause bone loss in PRE meno women.  

I found out that I had osteopenia in both of my hips.  My MO didn't seem concerned enough to prescribe anything for it ..just suggested that I start taking regular calcium, upped the vit D and increase weight bearing exercise.  

My MO said insurance will swing for another scan 2 years after the first.  I am doing all the doc suggested and am very interested to see if it has gotten better or worse at my next scan.  My hips do ache a little after running and I do worry that my bones are getting worse...but it could be aches from the tamoxifen...or aches from the fact that I'm 46 and have taken up running for the first time in my life!