Furthermore, patients treated with upfront ZOL had a significantly higher risk of bone pain than patients with delayed ZOL. More attentions should be paid to patients with musculoskeletal disorders. For patients with low risk of osteoporosis, immediate ZOL may be not needed due to additional adverse effects in some conditions. Or it can be stopped after the occurrence of these adverse events. Further randomized clinical trials with large sample size should

be taken to evaluate the side effects of ZOL, especially for musculoskeletal disorders. Conflict of interest The authors declare that they have no competing interests. Acknowledgements We are grateful to Dr. Jifu Wei (Clinical Experiment Center, the First Lonafarnib ic50 Affiliated Hospital with Nanjing JSH-23 molecular weight Medical University) for critical discussion in our study. This work was supported in part by Wu Jie-Ping Foundation (320.670010009), the National Natural Science Foundation of China (81071753), the Six Kinds of Outstanding

ARS-1620 clinical trial Talent Foundation of Jiangsu Province (To Wei He), the Science and Education for Health Foundation of Jiangsu Province (RC2007054), the Natural Science Foundation of Jiangsu Province (BK2008476, BK2009438 and BK2010581), the Program for Development of Innovative Research Team in the First Affiliated Hospital of NJMU (IRT-008), and A project Funded by the Priority Academic Program Development of Jiangsu higher Education Institutions (PAPD). References 1. Elmore JG, Armstrong K, Lehman CD, Fletcher SW: Screening for breast cancer. JAMA 2005, 293:1245–1256.PubMedCrossRef 2. Early Breast Cancer Trialists’ Collaborative Group (EBCTCG): Effects of chemotherapy and hormonal therapy for early breast cancer on recurrence and 15-year survival: an overview of the randomised trials. Lancet 2005, 365:1687–1717.CrossRef 3. Forbes JF, Cuzick J, Buzdar A, Howell A, Tobias JS, Baum M: Effect of anastrozole and tamoxifen as adjuvant treatment for early-stage breast cancer: 100-month analysis of the ATAC trial. Lancet Oncol 2008, 9:45–53.PubMedCrossRef 4. Coates AS, Keshaviah A, Thurlimann B, Mouridsen H, Mauriac L, Forbes JF, Paridaens R, Castiglione-Gertsch

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