Usefulness of real time elastography strain ratio in the assessment of cervical intraepithelial neoplasia and cervical cancer using a reference material

AIMS: To assess the usefulness of real time elastography (RTE) strain ratio (SR) in diagnosing cervical cancer (CC) and cervical intraepithelial neoplasia (CIN), using a synthetic experimental device (ED) as reference material. MATERIAL AND METHODS: Seventy-nine participants were enrolled, divided in three groups: Group 1 - benign cervix (n=39); Group 2 - CIN (n=32); Group 3 - CC (n=8). Transvaginal RTE was performed, with SR determination, as the ratio between the ED and the cervical tissue. Mean SR values of the groups were compared; diagnostic performance was assessed by tracing the receiver operating characteristic (ROC) curve. Area under the curve (AUC) was analyzed. Cut-off values were established. Pathological results were considered as reference for data interpretation. RESULTS: SR means significantly differed in Group 1 as compared to Groups 2 and 3 (p=0.001). Excluding 2 aberrant values in Group 3, assigned to cases complicated by hemorrhagic necrosis, statistical difference was also noted between Groups 2 and 3 (p=0.02). For Groups 1 and 3, AUC was 0.966 with a 95%CI (0.914-1.000); the cut-off point of SR was 1.42, with a sensitivity of 100% and a specificity of 94.9%. AUC was 0.752 with a 95%CI (0.629-0.876) for Groups 1 and 2. For the cut-off value of 1.03, sensitivity and specificity were 75% and 74%, respectively. CONCLUSION: RTE SR, performed with a synthetic reference material, seems a reliable method for distinguishing between benign uterine cervix and malignancy, with promising results as a complementary investigation in diagnosing CIN. However, SR becomes inoperant in cases of cancer complicated with hemorrhagic necrosis.