This is a prospective, randomized, single-center clinical trial evaluating whether early prophylactic radiotherapy to high-risk asymptomatic or minimally symptomatic bone metastases reduces the 1-year rate of skeletal-related events (SREs) in patients with metastatic solid cancers. Patients will be randomized in a 1:1 ratio to receive either standard of care systemic therapy or observation, or prophylactic radiotherapy in addition to standard of care. The primary endpoint is the 1-year rate of SREs. Secondary endpoints include adverse events, quality of life, economic burden, pain-free survival, and overall survival.