Impact of Nodal Stereotactic Body Radiotherapy on Time to Systemic Therapy Initiation: An Emerging Clinical Endpoint in Oligometastatic Disease

The oligometastatic paradigm has introduced metastasis-directed therapies as potential strategies to delay disease progression and postpone systemic treatment initiation. Among these approaches, stereotactic body radiotherapy (SBRT) has demonstrated high local control rates with limited toxicity in oligometastatic lymph node disease. Beyond survival outcomes, the ability of SBRT to defer systemic therapy represents an increasingly relevant clinical endpoint, particularly in patients requiring multiple treatment lines or experiencing cumulative treatment toxicity. Available data indicate a median freedom from systemic therapy of approximately 14 months, with nearly one-quarter of patients remaining systemic treatment–free at five years. Similarly, systemic therapy–free survival around 17.8 months has been reported in some series. These findings highlight the clinical importance of SBRT as a strategy to preserve quality of life while maintaining disease control. This review examines current evidence supporting systemic therapy deferral as a meaningful endpoint in nodal oligometastatic disease management.