Treated Ovarian Cancer: Comparison of MR Imaging with Serum CA-125 Level and Physical Examination—A Longitudinal Study

Abstract
To evaluate whether gadolinium-enhanced magnetic resonance (MR) imaging can demonstrate clinically occult tumors in women with treated ovarian cancer and to compare the diagnostic accuracy of MR imaging, serum CA-125 (ovarian cancer antigen) level, and physical examination. From 1992 to 1997, a longitudinal study comparing MR imaging findings, CA-125 values, and physical examination results with eventual clinical outcome in 69 women with treated ovarian cancer was performed. Tumor presence was determined with surgery, by an elevated CA-125 value, or with follow-up of patients longitudinally to assess for tumor recurrence. Absence of tumor was accepted with a disease-free interval of at least 2 years. Twenty-three of 39 patients in clinical remission with a normal CA-125 level and physical examination result had subclinical tumor proved at laparotomy or clinical follow-up. Gadolinium-enhanced MR imaging correctly demonstrated residual tumor in 20 of 23 patients. In all 69 patients, MR images had a 91% sensitivity, 87% specificity, 90% accuracy, and 72% negative predictive value and were superior to serum CA-125 level (53%, 94%, 63%, and 38%, respectively) (P < .001) and physical examination (26%, 94%, 43%, and 29%, respectively) (P < .001) in the depiction of residual tumor. Gadolinium-enhanced MR imaging is a valuable clinical tool in patients with ovarian cancer. An abnormal MR examination with a normal CA-125 value is a strong indication of residual or recurrent tumor.