Metastasectomy versus stereotactic body radiotherapy for patients with oligometastatic colorectal lung metastases: a systematic review

Metastasectomy and stereotactic body radiotherapy (SBRT) are both guideline-recommended treatment modalities for patients with oligometastatic colorectal lung metastases (CLM). Few evidence is available comparing different local therapies in an oligometastatic population. This systematic review aimed to compare the efficacy of metastasectomy with SBRT for patients with oligometastatic CLM. A systematic literature search was performed according to the PRISMA guidelines to identify studies on metastasectomy and SBRT for patients with oligometastatic CLM. Studies published between 2000 and 2023 were identified through Medline, Embase, and the Cochrane databases. Overall survival (OS), progression-free survival (PFS), and local recurrence rate (LRR) were assessed and compared between both groups. The risk of bias was assessed using the Grading of Recommendations, Assessment, Development, and Evaluation (GRADE) tool. A total of 141 studies on metastasectomy (n = 29932) and 16 studies on SBRT (n = 1381) were included in the final analysis. The pooled five-year OS was 52.2 % (CI: 49.8-54.5) and 45.0 % (CI: 31.2-58.9) following metastasectomy and SBRT, respectively (p = 0.213). The pooled five-year PFS was 35.1 % (CI: 32.2-38.1) following metastasectomy and 11.7 % (CI: 0-38.2) following SBRT (p < 0.001). The pooled LRR was 10.5 % (CI: 5.5-15.5) following metastasectomy and 28.1 % (CI: 20.8-35.4) following SBRT (p < 0.001). The average GRADE score of the included studies was low. The data suggest that patients with oligometastatic CLM have a comparable OS rate after metastasectomy or SBRT, but PFS and LRR favour a surgical approach. This systematic review supports initiating a randomized controlled trial comparing surgery and SBRT in operable patients with oligometastatic CLM.