OBJECTIVES

: A recent consensus guideline on the management of aromatase inhibitor-associated bone loss (AIBL) in postmenopausal women with hormone receptor positive breast cancer (BC) recommended the clinical use of bisphosphonates in the adjuvant setting as well as in bone-directed therapy. Little is known about the current aromatase inhibitor (AI) usage pattern and incorporation of bisphosphonates among BC patients receiving AI in Hong Kong. The aim of this pilot study is to analyze the prevalence of bisphosphonate therapy in women with BC treated with AI in Hong Kong.

METHODS

: This is a retrospective cross-sectional study. Women with BC who attended specialist outpatient clinic at a local tertiary hospital in the 1-week data collection period in March 2019, and were dispensed with an AI were included. Patient demographic, disease, drug use, and other clinical parameter information were collected and analyzed.

RESULTS

: A total of 71 women on AI therapy were reviewed in this study. The mean age was 62.8 ± 10.5 and the average duration of AI treatment was 31.2 months. All of the women were in postmenopausal state. Majority of the patients (80.3%; n=57) were prescribed with letrozole, and the remaining were on anastrozole (8.5%) and exemestane (11.3%). AI was used as the adjuvant hormonal treatment for early-stage disease in 31 (43.7%) of the sampled patients, where 19.4% of them incorporated bisphosphonate use. In the non-adjuvant setting, 22.5% of the cases involved concurrent bisphosphonate therapy. A large number of patients (45.1%) on AI were not taking any calcium/vitamin D supplementations. Finally, only 35.2% of all patients had at least one DEXA scan performed while they were on AI.

CONCLUSIONS

The prevalence of bisphosphonate use was relatively low in women with BC treated with AI. Further studies may be warranted to investigate on how to optimize use and monitoring.