Perfusion and diffusion characteristics of cervical cancer based on intraxovel incoherent motion MR imaging-a pilot study.

OBJECTIVES

To investigate the tissue characteristics of cervical cancer based on the intravoxel incoherent motion (IVIM) model and to assess the IVIM parameters in tissue differentiation in the female pelvis.

METHODS

Sixteen treatment-naïve cervical cancer and 17 age-matched healthy subjects were prospectively recruited for diffusion-weighted (b = 0-1,000 s/mm(2)) and standard pelvic MRI. Bi-exponential analysis was performed to derive the perfusion parameters f (perfusion fraction) and D* (pseudodiffusion coefficient) as well as the diffusion parameter D (true molecular diffusion coefficient) in cervical cancer (n = 16), normal cervix (n = 17), myometrium (n = 33) and leiomyoma (n = 14). Apparent diffusion coefficient (ADC) was calculated. Kruskal-Wallis test and receiver operating characteristics (ROC) curves were used.

RESULTS

Cervical cancer had the lowest f (14.9 ± 2.6%) and was significantly different from normal cervix and leiomyoma (p < 0.05). The D (0.86 ± 0.16 x 10(-3) mm2/s) was lowest in cervical cancer and was significantly different from normal cervix and myometrium (p < 0.05) but not leiomyoma. No difference was observed in D*. D was consistently lower than ADC in all tissues. ROC curves indicated that f < 16.38%, D < 1.04 × 10(-3) mm(2)/s and ADC < 1.13 × 10(-3) mm(2)/s could differentiate cervical cancer from non-malignant tissues (AUC 0.773-0.908).

CONCLUSIONS

Cervical cancer has low perfusion and diffusion IVIM characteristics with promising potential for tissue differentiation.

KEY POINTS: • Diffusion-weighted MRI is increasingly applied in evaluation of cervical cancer. • Cervical cancer has distinctive perfusion and diffusion characteristics. • Intravoxel incoherent motion characteristics can differentiate cervical cancer from non-malignant uterine tissues.