Pilot study of intravoxel incoherent motion sequence for grading and evaluating radiotherapy effect of cervical cancer

Objective: To investigate the feasibility of intravoxel incoherent motion (IVIM) for grading cervical cancer and evaluating effect of radiation treatment. Methods: The imaging and pathological findings of 23 patients with cervical cancer were analyzed retrospectively. The standard apparent diffusion coefficient (ADC_standard), diffusion coefficient (D), perfusion coefficient (D*) and perfusion score (f) on double exponential function analysis of well- and poorly-differentiated cancer were compared using t test. These parameters were also compared in 12 patients before and after radiotherapy. Results: The ADC_standard and D values of 13 poorly-differentiated tumors were significantly lower than that of 10 well-differentiated tumors (Z = -3.496, -2.660, P < 0.05). There was no significant difference in the areas under the curves of ADC_standard (0.965) and D (0.854), D* and f (t = -0.184, 1.072, P > 0.05) between the two groups. Tumor size and D values were significantly reduced after radiotherapy (Z = -1.999, P < 0.05) whereas the areas under the D, ADC_standard, D* and f value curves were not significantly different before and after treatment. Conclusions: IVIM analysis is feasible for grading cervical cancer and assessing response of radiotherapy. (authors)