Aim: The purpose of this study was to evaluate the efficacy of diffusion-weighted (DW) magnetic resonance (MR) imaging to predict the tumor response to chemoradiotherapy (CRT) of uterine cervical cancer.
Methods: Twenty-five consecutive patients with pathologically confirmed uterine cervical cancer underwent 1.5-T MR imaging including DW imaging before and during CRT. MR images were reviewed for the size and apparent diffusion coefficient (ADC). Pathological evaluation of the therapeutic effect was performed 3 months after finishing CRT, and we divided the subjects into two groups: complete remission (CR) (n=16) and residual tumor (n=9).
Results: ADC was lower before CRT than during CRT (0.89 ± 0.12 and 1.25 ± 0.22 × 10⁻³ mm²/s, respectively) (P<0.01). ADC change between before and during CRT (ΔADC) showed a moderate positive correlation (r=0.435, P<0.05) with the tumor regression rates. ΔADC was higher in the CR group than in the residual tumor group (0.43 ± 0.23 and 0.25 ± 0.15 × 10⁻³ mm²/s, respectively) (P<0.05). The CR rates were higher in the high ΔADC group (ΔADC ≥ 0.50) than in the low ΔADC group (ΔADC <0.49) (100% and 53%, respectively) but marginally significant (P=0.057). The local control rates were not statistically different between high and low ΔADC groups (83.3% and 73.7%, respectively) (P=0.602).
Conclusion: DW imaging including ADC measurement may be useful for prediction and early assessment of pathological response to CRT for uterine cervical cancer, but its impact on local disease-free survival was limited.
Keywords: chemoradiotherapy; diffusion-weighted imaging; magnetic resonance imaging; treatment response; uterine cervical cancer.
© 2013 The Authors. Journal of Obstetrics and Gynaecology Research © 2013 Japan Society of Obstetrics and Gynecology.