The American Society of Clinical Oncology (ASCO) is the world's leading professional organization that represents physicians who treat people with cancer. Using the best available evidence, ASCO's expert panels identify and develop practice recommendations for specific areas of cancer care that would benefit from the availability of practice guidelines.

In November 1999, ASCO adopted a guideline on "The Role of Bisphosphonates in Breast Cancer" and updated it in 2003 as the "2003 Update on the Role of Bisphosphonates and Bone Health Issues in Women With Breast Cancer."¹

Bisphosphonates can provide a supportive benefit to many patients with bone metastases. Current research is focusing on bisphosphonates as adjuvant therapy. Although new data are needed that address when to stop therapy, alternative doses or schedules for administration, and how to best coordinate bisphosphonates with other palliative therapies, they are not presently being investigated, according to the current guideline.¹

The use of bisphosphonates in women with nonmetastatic breast cancer follows whether patients are divided into high or low risk for osteoporosis.

High risk is defined by:

• All women older than 65 years
• All women aged 60 to 64 years with family history, body weight <70 kg, prior fracture, or other risk factors
• Postmenopausal women of any age who are receiving aromatase inhibitors
• Premenopausal women with therapy-associated premature menopause¹

Further guidelines for use of bisphosphonates approved by the US Food and Drug Administration include these situations:

• Patients with lytic disease, as seen on plain radiographs
  – Recommendation: pamidronate or zoledronic acid every 3 to 4 weeks
• Patients with a normal radiograph and abnormal bone results on bone scan, computed tomography (CT), or magnetic resonance imaging (MRI) that show bone destruction
  – Recommendation: pamidronate or zoledronic acid every 3 to 4 weeks
• Patients with a normal radiograph and results on bone scan, CT, or MRI that show no bone destruction
  – No bisphosphonate treatment is recommended
• Pain control
  – Recommendation: standard pain control plus intravenous (IV) pamidronate or IV zoledronic acid with systemic chemotherapy and/or hormonal therapy¹

The Figure (view) shows an algorithm that summarizes recommendations for use in breast cancer patients screened for osteoporosis risk; it includes bone mineral density and dual-energy x-ray absorptiometry.

Cancer Care Ontario²

• Recommendations:
  – In women with breast cancer and bone metastases: use oral clodronate, IV pamidronate, IV zoledronic acid
  – In patients with bone metastases and pain: use pamidronate, zoledronic acid, or clodronate as adjuncts to standard pain control

Cochrane Review³

• Recommendations:
  – In women with breast cancer and bone metastases: in addition to hormonal therapy or chemotherapy, use bisphosphonates, oral or IV, to reduce the risk of a skeletal event, increase the time to a skeletal event, and reduce bone pain

1.	Hillner BE, Ingle JN, Chlebowski RT, et al. American Society of Clinical Oncology 2003 update on the role of bisphosphonates and bone health issues in women with breast cancer [ASCO Special Article]. J Clin Oncol. 2003;21:4042-4057.
2.	Cancer Care Ontario Practice Guidelines Initiative. Use of bisphosphonates in women with breast cancer. Practice Guideline Report #1-11(Version 2.2002). Ontario, Can: Cancer Care Ontario & the Ontario Ministry of Health and Long-term Care. Available at http://www.cancercare.on.ca/pdf/pebc1-11s.pdf. Accessed December 2004.
3.	Pavlakis N, Stockler M. Bisphosphonates for breast cancer (Cochrane Review) (Abstract). In: The Cochrane Library, Issue 3, 2004. Chichester, UK: John Wiley & Sons, Ltd. Available at http://www.cochrane.org//cochrane/revabstr/ab003474.htm. Accessed November 2004.