Pain Response Rates After Conventional Radiation Therapy for Bone Metastases Assessed Using the International Consensus Pain Response Endpoints: A Systematic Review and Meta-Analysis of Initial Radiation Therapy and Re-Irradiation
A partir d'une revue systématique de la littérature publiée entre 2002 et 2021 (35 études), cette méta-analyse compare l'effet, sur les douleurs liées aux métastases osseuses, d'une radiothérapie initiale et d'une seconde irradiation
Purpose: Previous meta-analysis of conventional radiation therapy for painful bone metastases showed overall response (OR) rates of 72%–75% (evaluable patients), 61%–62% (intent-to-treat patients) for initial radiation therapy, and 68% for re-irradiation (evaluable patients). However, the definition of pain response differed among the studies included. Hence, we conducted a systematic review and meta-analysis to determine the pain response rates assessed by the International Consensus Pain Response Endpoints (ICPRE) for both initial radiation therapy and re-irradiation. Methods and Materials: The PubMed and Scopus databases were searched for articles published between 2002 and 2021. The inclusion criteria were: (i) prospective studies or studies based on prospectively collected data and (ii) studies in which pain response was assessed using ICPRE. Our primary outcomes of interest were the overall response (OR) rates (sum of the complete and partial response rates) for both initial radiation therapy and re-irradiation. Results: Of the 6470 articles identified in our database search, 32 and 3 met the inclusion criteria for the analysis of initial radiation therapy and re-irradiation, respectively. The OR rates of initial radiation therapy in evaluable patients (n=4775) and intent-to-treat patients (n=6775) were 60.4% (95% confidence interval [CI], 55.2–65.4) and 45.4% (95% CI, 38.7–52.4), respectively. The OR rates of re-irradiation in evaluable patients (n=733) and intent-to-treat patients (n=1085) were 70.8% (95% CI, 15.7–96.9) and 62.2% (95% CI, 5.3–98.0), respectively. Subgroup analyses of initial radiation therapy including the comparison of randomized and non-randomized studies showed no significant differences in any comparison, indicating similar response rates across different study designs. Conclusion: For initial radiation therapy, we determined the ICPRE-assessed response rates, which were lower than previously reported. The OR and complete response rates should be benchmarks for future randomized and non-randomized studies. For re-irradiation, the wide CIs demonstrate that the response rates based on ICPRE require further investigation.
International Journal of Radiation Oncology, Biology, Physics 2023