Intravoxel incoherent motion magnetic resonance imaging for evaluation of the efficacy of concurrent chemoradiotherapy in treatment of cervical cancer / 中华放射肿瘤学杂志

ABSTRACT

Objective To assess the histological characteristics of cervical cancer using intravoxel incoherent motion magnetic resonance imaging ( IVIMMRI) and to investigate the performance of IVIMMRI in evaluation of the efficacy of concurrent chemoradiotherapy in the treatment of intermediate/advanced cervical cancer. Methods Pelvic MRI scans, containing T2WI, IVIM (14 b values, b=0?1 000 s/mm2), and contrast?enhanced T1 scans were performed in 23 patients pathologically diagnosed with intermediate/advanced cervical cancer ( stage ≥Ⅱb ) before chemoradiotherapy, after two and four weeks of treatment, and at the end of treatment. The IVIMMRI data were processed with the bi?exponential model to generate three parameters, containing pure diffusion coefficient ( D ) , pseudodiffusion coefficient ( D?) , and perfusion fraction ( f ) . Apparent diffusion coefficient ( ADC ) was obtained using the mono?exponential model. The IVIMMRI parameters were measured at each time point and their dynamics and correlation were analyzed. Results The ADC, D, and f values were significantly higher after complete treatment ( 0?96 × 10-3 vs. 1?77 × 10-3 mm2/s, P=0?000;0?76 × 10-3 vs. 1.34± 0?12 × 10-3 mm2/s, P=0?000;0?14% vs. 0?24%, P=0?012). The above three values significantly increased after two weeks of treatment (all P=0?000) and kept increasing until the end of the treatment. In contrast, the D? value was reduced from the second week to the end of the treatment. Conclusions IVIMMRI can monitor the dynamic functional changes and early tumor responses during chemoradiotherapy for cervical cancer, which holds promise for clinical application.