Health-Related Quality of Life After SBRT for Oligoprogressive Disease: Results From a Phase II Prospective Trial

Purpose: This study aimed to report changes in patient-reported health-related quality of life (HRQoL) from a phase II trial evaluating stereotactic body radiation therapy (SBRT) for oligoprogressive (OP) tumors. The study hypothesis was that SBRT would not be associated with a deterioration in HRQoL. Methods and Materials: This single-arm, phase II prospective study enrolled patients with metastatic genitourinary (GU), breast, or gastrointestinal (GI) cancers with radiographic OP disease in fewer than 5 sites. All OP sites were treated with SBRT while patients continued their existing systemic therapy. HRQoL was assessed using the EORTC QLQ-C30 questionnaire at baseline, during radiation therapy, and at 6 weeks, 3 months, and 6 months post-SBRT. A minimally clinically important difference (MCID) was defined as a change >10 points. The primary endpoints were the changes in global health status (GHS) and the QLQ-C30 summary score at 6 months. Secondary endpoints included longitudinal GHS assessment over time. Results: Seventy patients were enrolled (32 GU, 23 breast, and 15 GI). At 6 months, any-site progression occurred in 56% of GU, 48% of breast, and 87% of GI patients. For the entire cohort, mean GHS and QLQ-C30 summary scores declined by 7 and 5 points, respectively (P = .02 and P = .03) neither reaching the MCID. Patients with GU cancer had no significant GHS change (P = .99), whereas patients with breast cancer experienced a statistically significant but nonmeaningful decline (P = .01). Patients with GI cancer had a statistically significant decline that reached the MCID, indicating a clinically meaningful deterioration (P = .007). Progression was an independent predictor of worse GHS at 6 months (P = .003). Among patients without progression, 83% maintained or improved GHS and 91% maintained or improved QLQ-C30 scores. Conclusions: SBRT for OP tumors is well tolerated. HRQoL declines were primarily driven by disease progression and were clinically meaningful in patients with GI. Patients without progression maintained stable HRQoL following SBRT.