Anabolic Meds for Estrogen Positive Breast Cancer - not an option?

Posted by prarysky @prarysky, 3 days ago

My oncologist has recommended a Reclast infusion for me and I'm trying to decide if this is the best option for me. Based on my research, I believe starting with an anabolic medication to build bone followed by a bisphosphonate to seal any bone gains is the ideal.

What complicates that ideal option for me, however, is my diagnosis. In the fall of 2024 at age 74 I was diagnosed with invasive ductal carcinoma in the right breast and DCIS in the left breast. Estrogen positive, HER2-, 4 sentinel nodes tested negative.

Although my cancer was staged as I-B or C (can't recall) , my Ki-67 score of 50% and an Oncotype DX score of 35 indicate my cancer is aggressive. That is why I opted for a double mastectomy.

I had the double mastectomy and reconstructive surgery in January 2025 followed by 4 rounds of chemotherapy (cytoxan and taxotere). I began an aromatase inhibitor (letrozole) July 2025 and my oncologist is recommending I stay on an AI for 10 years. In addition, I may start Kisqali, a CDK 4/6 inhibitor, if insurance covers that....a big if.

My oncologist recommended I start an osteoporosis drug immediately. My Dexa scan in August 2025 indicated osteopenia but my FRAX score indicated a major osteoporotic fracture risk of 23% and hip fracture risk of 7.7% in the next 10 years. Besides the Dexa findings, there is my age and being on an aromatase inhibitor for years

I also was diagnosed with atrial fibrillation in August 2023 and have been on eliquis since then. I"ve had 4 known afib episodes since then and had a heart ablation in September 2025. I have a feeling my cardiologist is going to recommend I stay on Eliquis because of my age and the various cancer drugs' affects on cardio health.

My oncologist first recommended Fosamax but I cannot take oral bisphosphonates because I have a swallowing disorder and a past history of GERD. Based on that history and the wish to prevent a fracture, one oncologist recommended Zometa and my current oncologist has recommended Reclast.

It seems to me that with my history, despite my desire to start with an anabolic, my options are limited. Reclast, indeed, may be my only option. I recently consulted with an endocrinologist and she said I absolutely cannot take Forteo or Tymlos. We didn't even discuss Evenity. I doubt I could take that anyway because my drug insurance doesn't cover it. I've also read concerns about taking it with cardio issues so maybe that's why she didn't even refer to it.

When I used AI (a different AI this time!), Google AI said
"Anabolic steroids are not typically used for treating osteoporosis in patients with estrogen-positive breast cancer, as they may not be safe or effective in this context. It's important to consult a healthcare provider for appropriate treatment options."

I'm wondering if anyone can offer any advice or insight on my options. One question is what does one do if the Reclast infusion does not prevent further bone loss. I assume it means you just keep taking Reclast but would guess there's a limit on the number of times you can do that.

Thanks in advance for any thoughts you might have!

Interested in more discussions like this? Go to the Osteoporosis & Bone Health Support Group.

gently | @gently | 2 days ago

prarysky, no answers but a couple of thoughts. The real reason for not taking Forteo or Tymlos is because of the risk of bone metastasis. Neither Forteo or Tymlos can cause the metastasis, but Zoledronic Acid (Zometa or Reclast) helps prevent bone metastasis. Prolia is thought to be better at preventing metastasis, but has other associated risks. Zometa is given at lower doses and more frequently. One advantage being that you are less likely to have the side effects (mostly achy joints) that patients are experiencing with the larger 5mg once a year Reclast.
Finally, congratulations on surviving invasive ductile carcinoma and on your brave surgical decision to reduce your risk. Best wishes for your continuing care and recovery and the survival of your obviously intact spirit.

prarysky | @prarysky | 2 days ago

Thank you gently! Your information about Forteo and Tymlos is helpful to know, especially since those critical details are seldom mentioned by any doctor I've seen. As much as I like my endocrinologist (she agreed to order bone turnover markers for me), she never explained why she opposed Forteo and Tymlos but her crystal clear position led me to learning about concern with those drugs if you're estrogen positive. As a side note, my oncologist who ordered the Reclast would not order bone marker tests for me saying she didn't know enough about them. She referred me to my primary care doc who has not yet responded to my request to order these tests.

I am frustrated by doctor opposition to baseline bone markers before starting osteoporosis drugs. Grrr!

Since the biology of my cancer cells so far has been on the aggressive side, I'll probably choose the Reclast or Zometa since I don't want to increase risks if any undetected cancer cells are circulating anywhere else in my body, e.g., my bones

This discussion group is so essential in broadening what I know. Additional info may not always be the answer to our prayers, but it at least offers those of us who want to go down the rabbit holes of research something more.

I've often read your thoughtful and knowledgeable posts and very much appreciate your response! You are a valuable resource!

I'll probably see if my current oncologist is willing to go with the lower dose of Zometa. Again that could be an insurance issue...don't know about that one. If not, I'll probably suck it up and have the Reclast infusion. Will mention the studies I've seen here about reduced dosages, but don't have high hopes she will deviate from the traditional protocol.

Peace & Health....