Stereotactic Body Radiation therapy for Liver Metastases: Systematic Review and Meta-Analysis With International Stereotactic Radiosurgery Society (ISRS) Practice Guidelines

Liver metastases remain one of the most challenging scenarios in modern oncology. Surgery has long been regarded as the gold standard, yet most patients are deemed ineligible due to comorbidities or technical constraints. Over the past two decades, stereotactic body radiation therapy (SBRT) has emerged as a noninvasive alternative, capable of delivering ablative doses of radiation with remarkable precision and minimal toxicity.

The reviewed meta-analysis encompassed 33 studies, including more than 3,000 patients and over 4,400 liver lesions. Findings revealed one-year local control rates of 85% and three-year rates of 68%, outcomes that compare favorably with other local ablative approaches, while severe toxicity occurred in only 3% of cases. Predictive factors shaping clinical outcomes included tumor size, cumulative treated volume, primary histology, and biologically effective dose (BED). Notably, BED values above 100 Gy were consistently associated with superior tumor control and survival, particularly in radioresistant colorectal metastases.

The guideline also offers practical recommendations for clinical application. SBRT is emphasized as a valuable option in the oligometastatic setting, especially for patients with up to three to five lesions or tumors located in anatomically challenging areas unsuitable for invasive procedures. The use of advanced motion management systems and image-guided technologies is considered essential to maximize treatment precision and safety.

Costa Rica within a healthcare system where access to complex hepatic surgery is limited and waiting times for invasive procedures are often prolonged, SBRT could represent a cost-effective and impactful strategy. Expanding advanced radiotherapy platforms within the public sector would provide patients with opportunities for curative intent or meaningful survival extension, particularly in a setting where colorectal and breast cancer incidence continues to rise. Incorporating these recommendations into national protocols could enhance equity and advance cancer care modernization.

Franzese C, Louie AV, Kotecha R, Zhang Z, Guckenberger M, Kim MS, Tree AC, Slotman BJ, Sahgal A, Scorsetti M. Stereotactic Body Radiation therapy for Liver Metastases: Systematic Review and Meta-Analysis With International Stereotactic Radiosurgery Society (ISRS) Practice Guidelines. Pract Radiat Oncol. 2025 Mar-Apr;15(2):e172-e188. doi: 10.1016/j.prro.2024.09.011. Epub 2024 Oct 16. PMID: 39419281.