Impact of intracavitary brachytherapy technique (2D versus 3D) on outcomes of cervical cancer: a systematic review and meta-analysis

Purpose To perform a systematic review and meta-analysis of the impact of brachytherapy (BT) technique (two-dimensional [2D] or three-dimensional image-guided [3D]) on outcomes of cervical cancer patients. Methods PubMed and EMBASE databases were searched up to April 16, 2019, for studies which evaluated the effect of 3D-BT compared to 2D-BT in cervical cancer. Endpoints included cumulative incidence of severe toxicity, locoregional recurrence-free survival (LRRFS), progression-free survival (PFS), and overall survival (OS). Hazard ratios (HRs) were pooled in the meta-analysis using the random-effects model. Results Six studies of eight cohorts were included in the quantitative synthesis. The pooled HR regarding toxicity was evaluated in five cohorts in three studies, and the HR of 3D-BT compared to 2D-BT was 0.54 (95% confidence interval [CI] 0.37-0.77). All six studies were included for the synthesis for LRRFS, and the pooled HR favors 3D-BT (0.61 [95% CI 0.40-0.93]). For PFS, three studies were included for analysis and 3D-BT was superior to 2D-BT (HR= 0.75 [95% CI 0.59-0.96]). Five studies were included for the pooled HR regarding OS, and pooled HR of 3D-BT compared to 2D-BT was 0.65 (95% CI 0.40-1.06). Conclusion 3D-BT might reduce severe toxicity and improve LRRFS and PFS in patients with cervical cancer. 3D-BT should be considered for standard management of cervical cancer, and efforts for adopting this procedure in Korea should be pursued.