Baseline Frailty, Treatment Intensity, and Clinical Outcomes Among Older Adults with Locally-advanced Prostate Cancer

Area of Science:

• Oncology
• Geriatric Medicine
• Health Services Research

Background:

• Androgen deprivation therapy (ADT) plus prostate radiation (RT) improves oncologic outcomes in locally-advanced prostate cancer (PCa).
• This combined treatment approach is underutilized in older adult populations.
• Frailty may influence treatment decisions and outcomes in this demographic.

Purpose of the Study:

• To emulate the NCIC CTG PR3/MRC PR07 trial in a real-world setting.
• To examine the oncologic outcomes of ADT + RT versus ADT alone in older adults with PCa.
• To investigate the role of frailty as an effect modifier in treatment selection and outcomes.

Main Methods:

• Observational study using SEER-Medicare data (2004-2017) of adults aged 66-89 with locally-advanced PCa.
• Frailty assessed using the claims-based frailty index (CFI).
• Oncologic outcomes evaluated using stabilized inverse probability of treatment weights (sIPW); treatment intensity association with CFI explored.

Main Results:

• ADT + RT was associated with reduced cancer-specific mortality (HR 0.61) and all-cause mortality (HR 0.84) in the overall cohort.
• These benefits were consistent across various clinical factors, including frailty levels.
• Increasing frailty was significantly associated with a lower probability of receiving ADT + RT (aOR 0.81 per unit CFI).

Conclusions:

• In older adults with locally-advanced PCa, increasing frailty is linked to reduced receipt of intensive ADT + RT.
• Despite this disparity, ADT + RT consistently demonstrates survival benefits across frailty spectrums.
• There is a critical need to address treatment disparities and ensure equitable care for frail older adults with PCa.