Are colposcopy and electrical impedance spectroscopy complementary when used to detect high-grade cervical neoplasia?

Purpose of investigation: To evaluate if colposcopy and electrical impedance spectroscopy (EIS) are complementary and hence increase the detection of high-grade cervical intraepithelial neoplasia (HG-CIN). Materials and Methods: A cohort of 1,237 women with an abnormal cervical cytology result referred to a single colposcopy service to assess the value of EIS as an adjunct to colposcopy for the detection of HG-CIN. Results: Fifty-three (12.8%) extra cases of HG-CIN were detected by a combination of colposcopy and EIS (466 vs. 413). Ten cases were referred with high-grade cytology and 43 were associated with low-grade cytology. The increased detection of I IG-CIN in women referred with low-grade cytology was 50% (129 vs. 86). The combination of colposcopy and EIS produced a highly significant improvement in the detection of HG-CIN. Conclusions: Comparison of the performance metrics with a previous multi-centre trial shows that use of EIS as an adjunct increases performance over that obtained from colposcopy alone. The largest improvement is in increased sensitivity and NPV when used to detect HG-CIN, particularly in women referred with low-grade cytology.