Iyengar P et al. -In patients with metastatic NSCLC sites of gross disease at presentation are the first to progress when treated with chemotherapy. In the current study, stereotactic ablative radiotherapy (SAbR) prior to maintenance chemotherapy nearly tripled the PFS in patients with limited metastatic NSCLC compared with maintenance chemotherapy alone.

Methods

• This is a single-institution randomized phase 2 study of maintenance chemotherapy alone versus SAbR followed by maintenance chemotherapy for patients with limited metastatic NSCLC.
• The tumors did not possess EGFR- or ALK-targetable mutations, but did achieve a partial response or stable disease after induction chemotherapy.

Results

• 29 patients were enrolled.
• 14 patients were allocated to the SAbR-plus-maintenance chemotherapy arm, and 15 patients were allocated to the maintenance chemotherapy–alone arm.
• The trial was stopped to accrual early after an interim analysis found a significant improvement in PFS in the SAbR-plus-maintenance chemotherapy arm of 9.7 months versus 3.5 months in the maintenance chemotherapy–alone arm.
• Toxic effects were similar in both arms.
• There were no in-field failures with fewer overall recurrences in the SAbR arm.
• Patients receiving maintenance therapy alone had progression at existing sites of disease and distantly.