Comparison of computed tomography and magnetic resonance imaging in cervical cancer brachytherapy: A systematic review

Abstract Purpose The aim of this overview was to assess the accuracy of computed tomography (CT)–based imaging technology and to compare it with magnetic resonance imaging (MRI) for the treatment planning of high–dose rate brachytherapy in cervical cancer. Methods and Materials A systematic search in PubMed, Embase, and the Cochrane Central was performed to identify clinical studies involving brachytherapy of cervical cancer and published before February 1, 2016. Outcomes of interest were geometric dimensions, dose parameters, and clinical results. Results After screening 675 articles, 13 clinical studies involving 465 patients were included for critical appraisal; 10 studies compared CT with MRI and three compared hybrid (CT/MRI based) with MRI only–based imaging technologies. The geometric dimensions of the high-risk clinical target volume (HR-CTV), dose parameters, and clinical outcomes were reported in 11, 10, and 1 studies, respectively. Conclusions Among those geometric parameters of HR-CTV, width was significantly overestimated on CT compared with MRI. Height might be underestimated, and thickness was comparable. The dose parameters for HR-CTV were lower on CT only–based technique compared with MRI-based one. It is proposed that at least one pre- or at brachytherapy MRI is required to assess the tumor extension. With the help of MRI information, CT contouring will be much more accurate in cervical cancer brachytherapy.