PURPOSE: Despite the increasing use of adjuvant bone-modifying agents (BMAs) such as zoledronate and clodronate in the treatment of patients with early stage breast cancer (EBC), little is known about real world practice patterns . A physician survey was performed to address this deficit and determine interest in clinical trials of alternative strategies for BMA administration .

METHODS: Canadian oncologists treating patients with EBC were surveyed via an anonymized online survey . The survey collected information on: physician demographics, knowledge and interpretation of adjuvant bisphosphonate guidelines, and real world prescribing practices . Questions also determined thoughts around the design of future adjuvant BMA trials .

RESULTS: Of 127 surveyed physicians, 53 eligible invitees responded (response rate 42 %). The majority of physicians are offering high-risk postmenopausal patients adjuvant BMAs . The most common BMA regimen was adjuvant zoledronate (45/53 , 85 %) every 6 months for 3 years . Concerns around toxicities and repeated visits to the cancer centre were perceived as the greatest barriers to adjuvant bisphosphonate use . Respondents were interested in future trials of de-escalation of BMAs comparing a single infusion of zoledronate vs. 6-monthly zoledronate for 3 years . The most favoured primary endpoints for such a trial included disease recurrence and fragility fracture rates .

CONCLUSION: Questions around optimal use of adjuvant bisphosphonates in patients with EBC still exist . There is interest among physicians in performing trials of de-escalation of these agents . The results of this survey will assist in designing pragmatic clinical trials to address this question.