Randomized phase 2 trial of microwave ablation versus stereotactic body radiotherapy for oligometastatic colorectal liver metastases

Local therapies can achieve durable disease control in selected patients with oligometastatic colorectal liver metastases (CRLM). Microwave ablation (MWA) is widely used, whereas stereotactic body radiotherapy (SBRT is a non-invasive alternative with limited prospective comparative evidence. The phase 2 LAVA-CRLM trial, at two centers in Copenhagen (Denmark) compared MWA versus SBRT for oligometastatic CRLM. Adults with one to three CRLMs, each ≤ 4.0 cm, deemed suitable for both MWA and SBRT with curative intent, were randomized 1:1 to MWA (n=47) or SBRT (n=45). At a median follow-up of 34.9 months , 1-year freedom from local progression was 77.7% with MWA and 83.0% with SBRT (HR 0.87; p=0.70). Grade 2 or higher toxicity occurred in 25% of patients with MWA and one patient (3%) with SBRT, whereas grade 3 or higher toxicity occurred only with MWA (8%), including one treatment-related death. The authors conclude that SBRT demonstrated a more favorable treatment-related safety profile compared with MWA, with no difference in freedom from local progression detected in this phase 2 trial.