Guidance for the prevention of bone loss and fractures in postmenopausal women treated with aromatase inhibitors for breast cancer: an ESCEO position paper

Aromatase inhibitors (AIs) are widely used in women with breast cancer, but they are known to increase bone loss and risk of fractures. Based on available evidence and recommendations, an ESCEO working group proposes specific guidance for the prevention of AIs-induced bone loss and fragility fractures. Aromatase inhibitors (AIs) are now the standard treatment for hormone receptor-positive breast cancer. However, deleterious effects of AIs on bone health have been reported. An ESCEO working group proposes guidance for the prevention of bone loss and fragility fractures in post-menopausal women with breast cancer receiving AIs. A panel of experts addressed the issue of skeletal effects of AIs and effectiveness of antifracture therapies for the prevention of AI-induced bone loss and fractures. Recommendations by national and international organizations, and experts' opinions on this topic were evaluated. All aromatase inhibitors are associated with negative effects on the skeleton, resulting in bone loss and increased risk of fragility fractures. Current guidelines suggest approaches that differ both in terms of drugs proposed for fracture prevention and duration of treatment. The ESCEO working group recommends that all AI-treated women should be evaluated for fracture risk. Besides general recommendations, zoledronic acid 4 mg i.v. every 6 months, denosumab s.c., or possibly oral bisphosphonates should be administered for the entire period of AI treatment to all osteoporotic women (T-score hip/spine <-2.5 or a parts per thousand yen1 prevalent fragility fracture), to women aged a parts per thousand yen75 irrespective of BMD, and to patients with T-score <-1.5 + a parts per thousand yen1 clinical risk factor or T-score <-1.0 + a parts per thousand yen2 clinical risk factors. Alternatively, therapy could be considered in patients with a FRAX-determined 10-year hip fracture probability a parts per thousand yen3%.