Bone Loss in Breast Cancer Survivors
Reported September 21, 2009
(Ivanhoe Newswire) Osteoporosis, which can be caused by certain cancer drugs, is a growing concern among breast cancer survivors and their doctors.
Many breast cancer patients also experience secondary causes of bone loss, such as vitamin D deficiency. Primary causes of osteoporosis are menopause and aging. Secondary causes are diseases or conditions that exacerbate bone loss.
A new study found bone loss can be halted with a comprehensive regimen that includes both osteoporosis drugs and treatments that target secondary causes of bone loss. Study leader Pauline Camacho, associate professor of medicine at Loyola University Chicago Stritch School of Medicine and director of Loyola’s Osteoporosis and Metabolic Bone Disease Center, was quoted as saying, “Doctors evaluating breast cancer patients for possible bone loss should look further than cancer drugs.”
A class of breast cancer drugs called aromatase inhibitors can decrease bone mineral density and increase the risk of fractures in postmenopausal women. The drugs decrease the body’s production of estrogen. While estrogen feeds cancer, the hormone also protects against osteoporosis. In certain breast cancer patients, bone loss from cancer drugs can be treated with osteoporosis drugs called bisphosphonates.
Camacho and colleagues reviewed charts of 81 breast cancer patients who were referred to Loyola’s Osteoporosis and Metabolic Bone Disease Center for treatment or prevention of osteoporosis. Fifty-one patients had secondary causes of bone loss, including Vitamin D deficiency, excessive calcium excretion in urine and an overactive parathyroid gland. Thirty patients did not have secondary causes of bone loss.
Each group received similar treatment with osteoporosis drugs. Women with secondary bone loss also received additional treatments. For example, vitamin D deficiency was treated with prescription doses of vitamin D supplements. Excessive calcium excretion was treated with a “water pill” that is also used to treat high blood pressure.
After one year, the breast cancer patients with secondary causes of bone loss had stable bone mineral density in their spines and necks. Bone mineral density also improved in the group of breast cancer patients who did not have secondary causes of bone loss.
Camacho said the study demonstrates that bone loss “can be prevented in women undergoing hormonal therapy if secondary causes of bone loss are corrected and bisphosphonate osteoporosis drugs are appropriately used.”
SOURCE: Presented at the annual meeting of the American Society for Bone and Mineral Research