Comparing Radiation Therapy to Usual Care for Patients With High-Risk Bone Asymptomatic Metastases, PREEMPT Trial

PRIMARY OBJECTIVE:

I. To determine whether prophylactic radiation therapy (RT) to high-risk asymptomatic bone metastases decreases the occurrence of skeletal-related events (SREs), including pathologic fracture, spinal cord compression, and surgery to bone (not including palliative radiation for pain only), compared to standard of care (SOC).

SECONDARY OBJECTIVES:

I. To compare overall survival (OS) between study arms. II. To compare occurrence of any SREs (including RT for palliation of pain) among enrolled bone metastasis(es) between study arms.

III. To compare occurrence of hospitalizations related to any SREs in enrolled bone metastasis(es) between study arms.

IV. To compare pain-related quality of life (QOL) between study arms. V. To characterize adverse events of RT and compare to SOC.

EXPLORATORY OBJECTIVES:

I. To evaluate overall QOL, functional status, and quality-adjusted life years between study arms.

II. To evaluate any hospitalizations (from any cause) between study arms. III. To characterize differences in primary and secondary endpoints between study arms (a) among the represented racial and ethnic groups (e.g. Black, White, Hispanic/Latino, Asian/Pacific Islander, and Native American), (b) by sex, and (c) by health-related social needs.

IV. To evaluate the heterogeneity of radiation treatment effect based on cancer-related factors (histology, criteria indicating high-risk for SRE), treatment-related factors (bone modifying agent use, radiation dose/ technique), and patient demographic factors (age, sex, race, ethnicity, and health-related social needs).

OUTLINE: Patients are randomized to 1 of 2 arms.

ARM I: Patients continue to receive SOC systemic anti-cancer therapy or observation and bone modifying agents as determined by the treating physician. Additionally, patients undergo optional blood sample collection on study.

ARM II: Patients continue SOC as in Arm I. Patients also undergo conventional RT or stereotactic body radiation therapy (SBRT) once daily (QD) for up to 5 days (5 fractions) in the absence of disease progression or unacceptable toxicity. Additionally, patients undergo computed tomography (CT) or magnetic resonance imaging (MRI) for RT planning and optional blood sample collection on study.

After completion of study treatment, patients are followed up at 3, 6, 12 and 24 months.