Technical success, technique efficacy and complications of minimally-invasive imaging-guided percutaneous ablation procedures of breast cancer: a systematic review and meta-analysis

Objectives: To systematically review studies concerning imaging-guided minimally-invasive breast cancer treatments. Methods: An online database search was performed for English-language articles evaluating percutaneous breast cancer ablation. Pooled data and 95% confidence intervals (CIs) were calculated. Technical success, technique efficacy, minor and major complications were analysed, including ablation technique subgroup analysis and effect of tumour size on outcome. Results: Forty-five studies were analysed, including 1,156 patients and 1,168 lesions. Radiofrequency (n=577; 50%), microwaves (n=78; 7%), laser (n=227; 19%), cryoablation (n=156; 13%) and high-intensity focused ultrasound (HIFU, n=129; 11%) were used. Pooled technical success was 96% (95%CI 94\u201397%) [laser=98% (95\u201399%); HIFU=96% (90\u201398%); radiofrequency=96% (93\u201397%); cryoablation=95% (90\u201398%); microwave=93% (81\u201398%)]. Pooled technique efficacy was 75% (67\u201381%) [radiofrequency=82% (74\u201388); cryoablation=75% (51\u201390); laser=59% (35\u201379); HIFU=49% (26\u201374)]. Major complications pooled rate was 6% (4\u20138). Minor complications pooled rate was 8% (5\u201313%). Differences between techniques were not significant for technical success (p=0.449), major complications (p=0.181) or minor complications (p=0.762), but significant for technique efficacy (p=0.009). Tumour size did not impact on variables (p>0.142). Conclusions: Imaging-guided percutaneous ablation techniques of breast cancer have a high rate of technical success, while technique efficacy remains suboptimal. Complication rates are relatively low. Key Points: \u2022 Imaging-guided ablation techniques for breast cancer are 96% technically successful. \u2022 Overall technique efficacy rate is 75% but largely inhomogeneous among studies. \u2022 Overall major and minor complication rates are low (6\u20138%)