Thinning of preserved stromal cervical ring at magnetic resonance imaging in patients with early cervical cancer: a possible predictor of extracervical invasion

The sensitivity of magnetic resonance (MR) imaging in predicting extracervical tumor invasion on the basis of the detection of a thinning of the uninvolved cervical stromal ring (3 mm or less) was compared to the sensitivity achieved by visualization of a complete stromal interruption. Fifty-seven consecutive patients with squamous carcinoma of the uterine cervix (FIGO stage IB-IIA), scheduled for radical surgery, were examined with axial and sagittal weighted MR sequences. The sensitivity in predicting extracervical involvement on the basis of the MR imaging visualization of a thinned stroma was 87.5%, whereas the sensitivity obtained by detection of a complete stromal interruption was 70%. Among women with a spared cervical stroma of more than 3 mm at MR imaging, only two had microscopic extracervical involvement at pathologic examination, accounting for a negative predictive value of 92.8%. The results of our study show a high concordance between MR imaging and pathologic findings, and indicate that the detection of an intact cervical stromal ring exceeding 3 mm at MR imaging is related to a very low risk of extracervical seeding of tumor. On the other hand, the detection of a thinned stromal ring is related to a high incidence of microscopic parametrial invasion. The information obtained by this imaging technique may therefore be extremely useful in accurate treatment planning for these patients.