Overview

The goal of this observational study is to evaluate the efficacy and safety of stereotactic body radiotherapy (SABR) in patients with oligometastatic or oligoprogressive cancer.

The main questions it aims to answer are:

1. oncologic outcomes (progression-free survival, local failure rate),
2. patient-reported outcomes,
3. physician-assessed toxicity, and
4. dynamics of circulating tumor DNA (ctDNA) for biomarker analysis.

Eligibility

Inclusion Criteria:

• Performance status (ECOG PS) 0-2
• Diagnosed with metastatic disease
• Confirmed to have oligometastatic/oligoprogressive cancer on imaging performed within 4 weeks (up to 5 lesions)

Exclusion Criteria:

• Patient with a history of prior radiotherapy to the site planned for SABR
• Patients with concomitant brain metastases