The Impact of Disease Progression on Health-Related Quality of Life Outcomes in Patients with Oligo-Metastatic Disease at 12-Months post Stereotactic Body Radiotherapy

Abstract

<h3>Purpose/Objective(s)</h3> Despite evolving data supporting stereotactic body radiotherapy (SBRT) as a treatment option in oligo-metastatic disease (OMD), there is a paucity of published health related quality of life (HRQOL) outcomes in this patient population. Furthermore, there is no data assessing the impact of disease progression on HRQOL in OMD patients. <h3>Materials/Methods</h3> Oligo-metastatic patients who received SBRT as part of a phase II single arm research ethics board approved study were included, with HRQOL was a secondary outcome. This study hypothesized that there is a different pattern of change from baseline HRQOL in patients with OMD treated with SBRT that have disease progression by 12-months (Group 2) compared to those that do not progress by 12-months (Group 1) as measured by the EORTC QLQ-C30 questionnaire. <h3>Results</h3> A total of 107 patients were included in this analysis, 41 without progression and 66 with progression by 12-months, median time to progression 7.7 (0.3-57) months. A statistically significant (SS) decline in the mean Global Health/Quality of Life (GHQOL) score (73 (SD 21.8) to 67.2 (SD 27.1), p=0.04) from baseline in the entire population at the 12-month follow-up was found. The mean GHQOL change score in Group 1 was -0.8 and in Group 2 -8.8, which were not SS different (p=0.07). However, only Group 2 demonstrated a SS difference between baseline and 12-month mean GHQOL scores (71.2 vs 62.4, p=0.01) and the mean GHQOL change score (-8.8) was within the range of a small minimal clinically important difference (MCID). Furthermore, there was a higher proportion of patients who experienced a MCID deterioration in Group 2 compared to Group 1 (37.4% vs 24.4%, p=0.14). <h3>Conclusion</h3> Patients who progress by 12-months do not have a SS difference in mean GHQOL change score compared to non-progressors. However, there are signals to suggest that patients who progress by 12-months post SBRT experience a different and worse pattern of change compared to those who do not progress.