SY7-2 - Treatment strategy of bone metastasis in breast cancer

Abstract

Bone is the most common site of metastasis in breast cancer. Among the subtypes of breast cancer, hormone dependent type, so-called luminal type, is the highest frequency type which occurs bone metastasis. For the successful treatment of bone metastasis, not only the anticancer agent but also the medicine preventing complications of the bone is necessary. Bone modifying agent (BMA) is effective against complications both skeletal related events (SREs) and bone pain. Blocking the remodeling of bone tissue by inhibiting osteoclast is the major mechanism of BMAs. Some clinical trials of breast cancer showed that the antitumor effect of bisphosphonates might depend upon a low estrogen environment. BMA also prevents bone loss in postmenopausal women who were receiving aromatase inhibitor. Osteonecrosis of the jaw (ONJ) is thought to be due to an infection of the tooth extraction socket which is protracted in wound healing by inhibiting remodeling of the bone by BMAs. Therefore, prevention of oral infection might be reduce the frequency of occurrence of ONJ. In conclusion, BMAs are essential to treat bone metastasis in breast cancer.