The Role of Magnetic Resonance Imaging in Pretreatment Evaluation of Early-Stage Cervical Cancer

Objective: The aim of this study is to evaluate the accuracy of magnetic resonance imaging (MRI) in the preoperative assessments of primary tumor size, parametrial invasion, and pelvic lymph node metastasis in patients with early-stage cervical cancer. Materials and Methods: A cohort of 125 patients with International Federation of Gynecology and Obstetrics stage IA2 to IIA cervical cancer who had preoperative MRI and underwent radical hysterectomy were enrolled and analyzed. The accuracy of preoperative MRI scan and pelvic examination in the measurement of tumor size was assessed based on postoperative measurement and pathologic findings. The accuracy of detection of lymph node status and parametrial invasion was also assessed by comparing the MRI and pathologic findings. Results: The mean diameter of the tumor size measured by postoperative measurement, MRI, and pelvic examination was 2.97 +/- 1.39 cm, 2.78 +/- 1.24 cm, and 1.97 +/- 1.70 cm, respectively. There were significant differences in the mean diameter of the tumor size between pelvic examinations and MRI scan or postoperative measurement (P < 0.0001). Based on postoperative measurement findings, accuracy of tumor size measurement between pelvic examination and MRI was determined by the degree of agreement with a difference of less than 0.5 or 1.0 cm. Pelvic examination and MRI had an accuracy of 24.75% and 39.60%, respectively, with a difference of less than 0.5 cm, and had an accuracy of 43.56% and 61.39%, respectively, with a difference of less than 1.0 cm. Correlation with postoperative measurement in tumor size was higher for MRI (r[s] = 0.481) than that for pelvic examination (r[s] = 0.362). The sensitivity, specificity, and accuracy of MRI in detecting lymph node metastasis were 27.78%, 85.98%, 77.60%, respectively. The negative predictive value of MRI in detecting parametrial invasion is 100%. Conclusions: Magnetic resonance imaging is an accurate noninvasive modality for preoperative evaluation of tumor size and also gives important information to parametrial invasion and lymph node status in patients with early-stage cervical cancer.