IntroductionPublished health-related quality of life (HRQOL) outcomes are lacking in patients treated for oligo-metastatic disease (OMD). The aim of this systematic review and individual patient data meta-analysis is to determine the effect of stereotactic body radiotherapy (SBRT) on HRQOL outcomes of patients with OMD. MethodsStudies screened included adults with extra-cranial OMD, defined as ≤ 5 metastases, SBRT intended as definitive treatment, and HRQOL as primary or secondary outcome. Primary outcome was change in HRQOL at 12-months from baseline in patients with OMD who received SBRT (versus not), reported as standardized mean difference (SMD). ResultsA total of 7556 publications were identified, four studies met inclusion criteria (2 single arm interventional studies and 2 randomised controlled trials [RCTs]), and individual patient data was available from 3 studies (175 patients). In the two RCTs, there was no SS difference in the SMD between patients who received SBRT and those that did not (0.09 [95 % CI −0.32, 0.5], P = 0.66). On meta-analysis of patients (N = 107) who received SBRT the SMDwas −0.23 (95 % CI [−0.42, −0.04], versus −0.25 (95 % CI [−0.57, 0.07]) in those who did not (N = 37) receive SBRT, demonstrating a small deterioration from baseline. ConclusionIn patients with OMD, there is no difference in HRQOL at 12-months from baseline between patients who received SBRT and those that did not. However, a small HRQOL deterioration was found in both groups of patients. More in-depth analysis of relevant HRQOL domains, in the setting of OMD, is required to better understand the potential impact of SBRT.