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      We appreciate Abdel-Razeq's comments on our review Caring for the Breast Cancer Survivor
      • Chalasani P.
      • Downey L.
      • Stopeck A.T.
      Caring for the breast cancer survivor: a guide for primary care physicians.
      and agree with his comment that tamoxifen's effects on bone mineral density vary with the menopausal status of the patient. Tamoxifen does cause bone loss in women who continue to have active menstrual cycles. However, for the majority of premenopausal women with breast cancer, treatment with chemotherapy results in amenorrhea. Thus, when they subsequently start their adjuvant hormonal treatment with tamoxifen, they are in effect postmenopausal. In premenopausal women treated with surgery and radiation therapy alone, adjuvant hormonal treatment with tamoxifen does induce bone loss when combined with complete ovarian suppression. In the Austrian study of Gnant et al,
      • Gnant M.F.X.
      • Mlineritsch B.
      • Luschin-Ebengreuth G.
      • et al.
      Zoledronic acid prevents cancer treatment-induced bone loss in premenopausal women receiving adjuvant endocrine therapy for hormone-responsive breast cancer: a report from the Austrian Breast and Colorectal Cancer Study Group.
      treatment with tamoxifen did induce osteopenia in 46% of the patients. Concomitant use of zoledronic acid prevented bone loss in patients receiving adjuvant hormonal treatment with tamoxifen or the aromatase inhibitor anastrozole.
      • Gnant M.F.X.
      • Mlineritsch B.
      • Luschin-Ebengreuth G.
      • et al.
      Zoledronic acid prevents cancer treatment-induced bone loss in premenopausal women receiving adjuvant endocrine therapy for hormone-responsive breast cancer: a report from the Austrian Breast and Colorectal Cancer Study Group.
      Tamoxifen has been shown to reduce bone density preferentially in the lumbar spine compared with the femoral neck. The lumbar spine is composed primarily of cancellous bone, whereas the femoral neck is predominantly cortical bone. Because cancellous bone has higher bone turnover compared with cortical bone, the lumbar spine is more affected by tamoxifen-induced bone suppression.
      It should be stressed that the bone loss induced by tamoxifen is modest, less severe than that seen with aromatase inhibitors, and worse in the first year after initiating treatment. In addition, studies to date have failed to show that tamoxifen-induced bone loss translates into clinically relevant fractures.
      • Powles T.J.
      • Hickish T.
      • Kanis J.A.
      • Tidy A.
      • Ashley S.
      Effect of tamoxifen on bone mineral density measured by dual-energy x-ray absorptiometry in healthy premenopausal and postmenopausal women.
      • Vehmanen L.
      • Elomaa I.
      • Blomqvist C.
      • Saarto T.
      Tamoxifen treatment after adjuvant chemotherapy has opposite effects on bone mineral density in premenopausal patients depending on menstrual status.
      Hormone therapy-induced bone loss also has been shown to be at least partially reversible on discontinuing therapy, especially in women who regain ovarian function.
      • Gnant M.F.X.
      • Mlineritsch B.
      • Luschin-Ebengreuth G.
      • et al.
      Zoledronic acid prevents cancer treatment-induced bone loss in premenopausal women receiving adjuvant endocrine therapy for hormone-responsive breast cancer: a report from the Austrian Breast and Colorectal Cancer Study Group.
      Dr Abdel-Razeq's comments remind us that we need to assess all our breast cancer survivors for risks of osteoporosis independently of their adjuvant hormonal therapies.

      References

        • Chalasani P.
        • Downey L.
        • Stopeck A.T.
        Caring for the breast cancer survivor: a guide for primary care physicians.
        Am J Med. 2010; 123: 489-495
        • Gnant M.F.X.
        • Mlineritsch B.
        • Luschin-Ebengreuth G.
        • et al.
        Zoledronic acid prevents cancer treatment-induced bone loss in premenopausal women receiving adjuvant endocrine therapy for hormone-responsive breast cancer: a report from the Austrian Breast and Colorectal Cancer Study Group.
        J Clin Oncol. 2007; 25: 820-828
        • Powles T.J.
        • Hickish T.
        • Kanis J.A.
        • Tidy A.
        • Ashley S.
        Effect of tamoxifen on bone mineral density measured by dual-energy x-ray absorptiometry in healthy premenopausal and postmenopausal women.
        J Clin Oncol. 1996; 14: 78-84
        • Vehmanen L.
        • Elomaa I.
        • Blomqvist C.
        • Saarto T.
        Tamoxifen treatment after adjuvant chemotherapy has opposite effects on bone mineral density in premenopausal patients depending on menstrual status.
        J Clin Oncol. 2006; 24: 675-680

      Linked Article

      • Caring for the Breast Cancer Survivor
        The American Journal of MedicineVol. 124Issue 2
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          We read with interest the nice review, “Caring for the breast cancer survivor,” by Chalasani et al in the Journal.1 The effect of tamoxifen use on bone health in breast cancer survivors needs further clarification.
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