Short-term quality of life after metastases-directed SBRT: Results of the ESTRO & EORTC OligoCare cohort.

Abstract

Metastasis-directed stereotactic body radiotherapy (SBRT), in combination with systemic therapy, is increasingly used in patients with oligometastatic disease (OMD), supported by international guidelines. However, real-world data on health-related quality of life (HRQoL) following SBRT remain limited. This study aimed to describe baseline HRQoL, evaluate changes over time, and identify clinical factors associated with HRQoL and its evolution. OligoCare is a pragmatic, prospective cohort study within the E²-RADIatE registry, including patients with oligometastatic breast, colorectal, non-small cell lung cancer (NSCLC), and prostate cancer treated with SBRT. An optional HRQoL sub-study assesses patient-reported outcomes at baseline and within 6 months post-SBRT. Analyses included descriptive assessment of baseline HRQoL, multivariable regression to identify factors associated with baseline global health status (GHS), and longitudinal evaluation of HRQoL changes. Clinically meaningful changes were defined using a minimal clinically important difference (MCID) of ≥ 10 points. Of 2,041 patients, 1,033 (50.6%) completed baseline HRQoL questionnaires and 450 (22%) had follow-up data. The median time to follow-up HRQoL assessment was 2.7 months (range 0.5-6.1). Median baseline GHS was 75. Higher baseline GHS was associated with prostate cancer and good performance status (p < 0.0001). At follow-up, mean GHS remained stable (71, SD 19). Among patients with follow-up data, 23% reported worsened HRQoL, 15% improved. No significant associations were found between HRQoL changes and clinical variables. Early findings support that SBRT for OMD maintains overall HRQoL in most patients, reinforcing its role in multimodal treatment without compromising patient-reported outcomes.