ASCO GU 2023: Barriers to Guideline-Concordant Use of Bone Modifying Agents for Prostate Cancer

( The 2023 American Society of Clinical Oncology Genitourinary (ASCO GU) cancers symposium held in San Francisco, CA between February 16th and 18th was host to a prostate cancer poster session. Dr. Aaron Mitchell presented the results of his group’s study evaluating barriers to the adoption of guideline-concordant use of bone modifying agents for prostate cancer patients.

Dr. Mitchell began by noting that National Comprehensive Cancer Network (NCCN) guidelines currently recommend the use of bone-modifying agents (BMAs) to reduce the incidence of skeletal-related events (SRE) in patients with metastatic castrate-resistant prostate cancer (mCRPC) with bone metastases, but not those metastatic castration-sensitive prostate cancer (mCSPC).1 Prior studies have demonstrated both the underuse of BMAs for patients with mCRPC and overuse for those with mCSPC. The underlying reasons for this current implementation gap remain unknown.

Using qualitative research methods, physicians who treat prostate cancer within an academic medical center setting and an affiliated network of community-based practices were interviewed by an experienced moderator using a semi-structured interview guide. Participants were queried regarding their experiences and perceptions around the current NCCN Guidelines recommendations, guideline adherence and non-adherence, and barriers to such adherence. Interviewees were also queried regarding their views about potential interventions to promote guideline-concordant BMA usage. Participants used Likert-scale items to rate the likely effectiveness of each intervention in influencing BMA practice patterns. They also identified the three most helpful interventions for reducing BMA underuse and overuse separately.

Nineteen physician were approached for an interview request, of whom 15 (79%) eventually participated. Of note, one of the four physicians declined the request as he/she did not treat mHSPC/mCRPC patients. The interview responses were as follows:

  • All respondents indicated that they were aware of the recommendation for use of BMAs in CRPC patients with bone metastases.
  • Two of 14 (14%) indicated that they were unaware of the recommendation against BMA use in patients with mCSPC
  • Four of 14 (29%) stated their belief that BMA use could be appropriate for mCSPC patients, depending on the burden of metastatic disease
  • Five of 14 (36%) were unaware of the recommendations for baseline DEXA scan and BMA for patients with low bone mineral density
  • The most commonly identified barriers (occurring “often” or “sometimes”) to BMA use for mCRPC patients were:
    • Obtaining dental clearance (11/15)
    • Insufficient time in clinic (6/15)
  • The interventions perceived as most helpful to reduce underuse for mCRPC were dental navigation (11/15) and EMR-based guidance (9/15).
  • The interventions identified as most helpful to reduce overuse for mCSPC were peer-to-peer education (14/15) and EMR-based guidance (13/15).

Dr. Mitchell concluded that among physicians treating prostate cancer within the setting of an academic center and affiliated, network community-based practices, there is incomplete awareness of guideline recommendations for screening and treatment of low bone mineral density, and against BMA use for SRE prevention in mCSPC patients. The preferred implementation strategies to minimize the risks of corresponding BMA underuse/overuse were dental navigation, peer-to-peer education, and electronic medical record-based guidance.

Presented by: Aaron Philip Mitchell, MD, MPH, Assistant Professor, Department of Medical Oncology, Memorial Sloan Kettering Cancer Center, New York City, NY

Written by: Rashid Sayyid, MD, MSc – Society of Urologic Oncology (SUO) Clinical Fellow at The University of Toronto, @rksayyid on Twitter during the 2023 American Society of Clinical Oncology Genitourinary (ASCO GU) Cancers Symposium, San Francisco, CA, February 16th – February 18th, 2023. 


  1. Schaeffer EM, et al. NCCN Guidelines® Insights: Prostate Cancer, Version 1.2023. J Natl Compr Canc Netw 2022;20(12):1288-1298.