Top Line: Radiation has an important role to play in the management of stage IV NSCLC.
The Study: Historically our role was mostly palliative, but expanding systemic options and data implicating the primary tumor as an ongoing source of polyclonal seeding have renewed interest in radical primary-directed RT. Note that we’re talking specifically about definitive local therapy here rather than just metastasis directed therapy for oligometastatic disease. This IASLC consensus statement synthesizes the current evidence supporting definitive treatment to the primary tumor for stage IV NSCLC. The strongest signal remains in EGFR-mutant oligometastatic disease where a phase 3 study has shown improved PFS and OS when definitive RT was given along with a first generation TKI. SINDAS showed similar gains when RT was delivered to all sites for EGFR-mutated disease. For those without actionable mutations, a randomized dose-escalation trial (63 vs 45 Gy with concurrent chemo) improved locoregional PFS and OS at the expected cost of more esophagitis and grade 3–4 pneumonitis. Their headline recommendations were that early consolidation after induction systemic therapy is the most promising sequencing of definitive RT. Higher doses are preferred with fractionation depending on location. Omitting involved nodal volumes to preserve immunotherapy efficacy is biologically appealing but not yet prospectively validated. Finally, concurrent SBRT with dual-agent IO or chemo-IO warrants caution given the potential risk of pneumonitis seen in trials like S1914. Of note, pneumonitis rates generally appear additive rather than synergistic.
TBL: Growing data supports definitive RT to the primary tumor in select patients with stage IV NSCLC, particularly those with targetable mutations. Several ongoing phase 3 trials (NIRVANA-Lung, PRIME-Lung, TOURIST, MARS) should clarify whether non-mutated patients derive similar benefit from definitive treatment of the primary. | McMahon, J Thorac Oncol 2026
The Study: Historically our role was mostly palliative, but expanding systemic options and data implicating the primary tumor as an ongoing source of polyclonal seeding have renewed interest in radical primary-directed RT. Note that we’re talking specifically about definitive local therapy here rather than just metastasis directed therapy for oligometastatic disease. This IASLC consensus statement synthesizes the current evidence supporting definitive treatment to the primary tumor for stage IV NSCLC. The strongest signal remains in EGFR-mutant oligometastatic disease where a phase 3 study has shown improved PFS and OS when definitive RT was given along with a first generation TKI. SINDAS showed similar gains when RT was delivered to all sites for EGFR-mutated disease. For those without actionable mutations, a randomized dose-escalation trial (63 vs 45 Gy with concurrent chemo) improved locoregional PFS and OS at the expected cost of more esophagitis and grade 3–4 pneumonitis. Their headline recommendations were that early consolidation after induction systemic therapy is the most promising sequencing of definitive RT. Higher doses are preferred with fractionation depending on location. Omitting involved nodal volumes to preserve immunotherapy efficacy is biologically appealing but not yet prospectively validated. Finally, concurrent SBRT with dual-agent IO or chemo-IO warrants caution given the potential risk of pneumonitis seen in trials like S1914. Of note, pneumonitis rates generally appear additive rather than synergistic.
TBL: Growing data supports definitive RT to the primary tumor in select patients with stage IV NSCLC, particularly those with targetable mutations. Several ongoing phase 3 trials (NIRVANA-Lung, PRIME-Lung, TOURIST, MARS) should clarify whether non-mutated patients derive similar benefit from definitive treatment of the primary. | McMahon, J Thorac Oncol 2026