Potentialities of multi-b-values diffusion-weighted imaging for predicting efficacy of concurrent chemoradiotherapy in cervical cancer patients

Background To testify whether multi-b-values diffusion-weighted imaging (DWI) can be used to ultra-early predict treatment response of concurrent chemoradiotherapy (CCRT) in cervical cancer patients and to assess the predictive ability of concerning parameters. Methods Fifty-three patients with biopsy proved cervical cancer were retrospectively recruited in this study. All patients underwent pelvic multi-b-values DWI before and at the 3rd day during treatment. The apparent diffusion coefficient (ADC), true diffusion coefficient (D.sub.slow), perfusion-related pseudo-diffusion coefficient (D.sub.fast), perfusion fraction (f), distributed diffusion coefficient (DDC) and intravoxel diffusion heterogeneity index([alpha]) were generated by mono-exponential, bi-exponential and stretched exponential models. Treatment response was assessed based on Response Evaluation Criteria in Solid Tumors (RECIST v1.1) at 1 month after the completion of whole CCRT. Parameters were compared using independent t test or Mann-Whitney U test as appropriate. Receiver operating characteristic (ROC) curves was used for statistical evaluations. Results ADC-T0 (p = 0.02), D.sub.slow-T0 (p < 0.01), DDC-T0 (p = 0.03), ADC-T1 (p < 0.01), D.sub.slow-T1 (p < 0.01), [DELA]ADC (p = 0.04) and [DELA][alpha] (p < 0.01) were significant lower in non-CR group patients. ROC analyses showed that ADC-T1 and [DELA][alpha] exhibited high prediction value, with area under the curves of 0.880 and 0.869, respectively. Conclusions Multi-b-values DWI can be used as a noninvasive technique to assess and predict treatment response in cervical cancer patients at the 3rd day of CCRT. ADC-T1 and [DELA][alpha] can be used to differentiate good responders from poor responders. Keywords: Cervical cancer, Diffusion magnetic resonance imaging, Concomitant Chemoradiotherapy