Sonographic Evaluation of Radiotherapy Response in Cervical Cancer: Correlation of MRI Findings with Resistive İndices

Aim: To assess prospectively the role of resistive indicies (RI) in determining the response to radiotherapy by transvaginal color doppler ultrasound (TVCDUS) and to correlate the results with MRI findings. Material and Method: 13 patients with advanced stage (>stage IIA) cervical cancer evaluated by MRI of the pelvis and TVUS before and 6 months after radiotherapy treatment. The mean resistive indicies before and after daiotherapy were measured from the periphery and the center of the tumor and were compared. These values were further correlated with both MR findings and RI values of the control group. Results: B mode TVUS identified the mass of all patients before therapy. RI measured 0.20-0.82 (mean=0.52) and 0.70-0.99 (mean=0.81) before and after the radiotherapy respectively in 13 patients. 11 showed full response clinically and accordingly, MR showed no residual tumor. MR examination and US showed residual tumor in two patients. The increase in RI before and after the radiotherapy was statistically significant (p=0.001) in the full response group. RI did not increase in two patients with residua. The mean RI measured from the control group was 0.65 and was significantly higher than the RI of the patients measured before therapy. Conclusion: Spectral features of TVCDUS can be a good alternative in the follow up response of cervix carcinoma to therapy, since a significant correlation between MRI findings and RI measurements are found.