Bone mineral density in women with non-metastatic breast cancer: Effect of intravenous bisphosphonates given before adjuvant therapies

Abstract

11038 Background: Adjuvant therapies shown survival improve of non-metastatic breast cancer (NMBC) patients, but they also decrease bone mineral density (BMD). Bisphosphonates are effective agents for the management of osteoporosis. Intravenous zoledronate, which is approved for the treatment of malignant hypercalcemia, multiple myeloma, and skeletal metastases, can suppress bone resorption and are often considered first-line therapy for the treatment of osteoporosis. We have analyzed the effects of chemotherapy on BMD of women with NMBC who received before adjuvant therapies intravenous bisphosphonates (zoledronic acid). Methods: We prospectively studied the effects of a single intravenous zoledronic acid dose (4 mg), on BMD of 74 women with NMBC (stage I-III), administred previous to the adjuvant therapies. The patients were referred to the Medical Oncology Service of University Hospital of Canary Islands between 2003 y 2006. Lumbar and hip BMD (g/cm2) was measured at diagnosis and after chemotherapy. The results were compared with a group of 80 patients with NMBC who received adjuvant therapy without intravenous bisphosphonates. Results: Breast cancer patients the median age was 52 ± 10 years old and the body mass index was 28,2 ± 5.5 kg/m2. At baseline there were not differences in BMD between the group that received bisphosphonates and the group with only chemotherapy at any of lumbar or femoral bone sites. In our study, the BMD after chemotherapy and intravenous bisphosphonates (n=74) significantly increased at femoral neck (0.805 ± 0.01, 0,826± 0.12; p=0.002) and trochanter (0.709 ± 0.01, 0.724 ± 0.01; p=0.002) and remained stable at lumbar, intertrochanter, total hip and Ward’s triangle; whether the group without bisphosphonates significantly decreased at lumbar (1.014 ± 0; 0.995 ± 0, p=0.0001), trochanter (0.701± 0; 0.690 ± 0, p=0,046), intertrochanter (1,095 ± 0; 1.078 ± 0, p=0.0001) and total hip (0,924 ± 0; 0.915 ± 0, p=0.046) areas (table). Conclusions: Women with NMBC are affected by early bone loss after adjuvant chemotherapy. Bisphosphonates intravenous (zoledronic acid) given before adjuvant therapy might be an effective treatment for this bone loss, increasing BMD or remaining stable. No significant financial relationships to disclose.