Application of diffusion-weighted imaging in therapeutic evaluation and prediction of concurrent chemoradiotherapy for cervical squamous cell carcinoma

Abstract

Objective To explore the value of diffusion-weighted imaging (DWI) on evaluation and prediction of therapeutic outcome in concurrent chemoradiotherapy for cervical squamous carcinoma. Methods 26 cases of cervical squamous carcinoma were examined by MRI before and one month after concurrent chemoradiotherapy. The patients were divided according to tumor response evaluated by Response Evaluation Criteria in Solid Tumors (RECIST). Apparent diffusion coefficient (ADC) values and the receiver operating characteristic (ROC) curve analysis were carried out before and one month after treatment. Results 26 cases had higher mean ADC one month after the concurrent chemoradiotherapy than that before treatment [(1.542±0.189) × 10-3 mm2/s vs (0.898±0.096) × 10-3 mm2/s, P < 0.05]. After the treatment, there were 17 cases of complete remission (CR) and 9 cases of partial remission (PR). ADC value in PR group was higher than that in CR group [(0.960±0.115) × 10-3 mm2/s vs (0.864±0.067) × 10-3 mm2/s, P < 0.05]. ROC curve showed that with 0.927 × 10-3 mm2/s of ADC as threshold to determine the tumor remission, the sensitivity and specificity were 66.7 % and 76.5 %, respectively, and the area under the ROC curve was 0.752 (P < 0.05). At one month after treatment, the tumor volume was decreased in different degrees in CR group and PR group, and the differences of ADC had statistical significance between the two groups [(1.603±0.183) × 10-3 mm2/s vs (1.427±0.146) × 10-3 mm2/s, P < 0.05]. ROC curve showed that with 1.444 × 10-3 mm2/s of ADC as a threshold for diagnosing tumor residual, the sensitivity and specificity were 76.5 % and 55.6 % respectively, and the area under the ROC curve was 0.765 (P < 0.05). Conclusions DWI as a useful supplement, can help to precisely evaluate the tumor response after the concurrent chemoradiotherapy and monitor the effects of the treatment. Besides, the ADC before chemoradiotherapy has the predictive value on short-term prognosis in cervical squamous cell carcinoma. Key words: Uterine cervical neoplasms; Treatment outcome; Diffusion-weighted imaging; Apparent diffusion coefficient