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Is calcium always necessary with anastrazole?

Bunty500
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My younger sister and I have both had breast cancer and a mastectomy. We’re both post menopausal and now both on anastrazole, but I’m also on calcium tablets too. She wasn’t sent for a bone density scan before she requested it and now her gp is saying that she doesn’t need calcium as her bone density is fine. I’m worried because she’s an asthmatic, uses steroid inhalers and any loss of bone density in her spine could eventually cause very significant problems. I understood that because of the effect on bone density, she should have regular bone density checks and calcium should be given along with anastrazole. Have I got it wrong? I’d really appreciate some advice and/or reassurance.

  • Dear Bunty 500,

    Thank you for getting in touch with us at the online community. My name is Penelope and I am one of the Cancer Information Nurse Specialists. I can appreciate that differences between the treatment that you and your sister are having must be confusing. Although there are clear similarities in the treatment that you have had so far, it is important to remember that treatment for cancer will be tailored to the needs of each individual so treatments can vary.  

    The NICE (National Institute for Health and Care Excellence) guidelines for bone health suggest a baseline DEXA scan to assess bone density when starting an aromatase inhibitor such as anastrozole. There is no specific guidance given as to the prescription of calcium. If you wish to see the NICE guidance it is point 1.9.4 and can be seen in this link. Please do bear in mind that these guidelines are written for medical professionals.

    Whilst I have been unable to find any national guidance on calcium supplementation, there is a 2008 document called Guidance for the Management of Breast Cancer Treatment-Induced Bone Loss which the NICE guidance refers to. The document can be seen here. This document includes algorithms of proposed management of bone loss in early breast cancer. Algorithm 2 on page 21 is for post-menopausal women receiving treatment with aromatase inhibitors. This document may inform breast care teams and GPs in the management of patients, but it is not official guidance. The algorithm refers to the T score from the bone density scan and gives an associated classification of risk. The low risk category is for lifestyle advice only. Whereas medium risk is to supplement if calcium and vitamin D levels are low.

    As I said this is for guidance only so that fact that you have been started on a calcium supplement does not necessarily mean that you are at an increased risk of osteoporosis yourself. The information from Breast Cancer Now on the side effects of anastrozole suggests that a supplement is one way to increase intake of calcium and vitamin D. It does not say this will necessarily be prescribed. It also highlights the benefits of not smoking and weight bearing exercise.

    You may wish to find out the results of your bone density studies if you don’t know them already, and your sister may wish to discuss things further with her breast care team.  They should be able to clarify what calcium intake they would recommend and any guidelines on which this is based.   

    I appreciate that the apparent lack of guidance can make things unclear. It is also important to be aware that in some cases excess calcium can cause its own side effects.  You or your sister could also speak to a Boots Macmillan Information Pharmacist to get further information about anastrozole and management of side effects.

    If you would like to discuss things further with one of the nurses please don’t hesitate to give us a ring on the Macmillan Support Line on the number below.

     

    Best wishes,

     

    Penelope, Information Nurse Specialist 

    You can also speak with the Macmillan Support Line team of experts. Phone free on 0808 808 0000 (7 days a week, 8am-8pm) or send us an email. 

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