ELECTROPOTENTIAL MEASUREMENTS AS A NEW DIAGNOSTIC MODALITY FOR BREAST-CANCER

Background Proliferative changes in breast epithelium are an intrinsic aspect in the development of breast cancer, and result in regions of epithelial electrical depolarisation within the breast parenchyma, whi ch can extend to the shin surface. Diagnostic information might be obt ained from a non-imaging and non-invasive test based on shin-surface e lect ro potentials. Methods In 661 women, scheduled for open biopsy at eight European centres, we studied whether measurements of breast ele ctrical activity with surface sensors could distinguish benign from ma lignant breast disease. A depolarisation index was developed. Results We found a highly significant trend of progressive electrical changes according to the proliferative characteristics of the biopsied tissue. Discriminatory information was obtained in both premenopausal and pos tmenopausal women, and the index was not related to age. The best test performances were for women with palpable lesions. The median index w as 0.398 for nonproliferative benign lesions, 0.531 for proliferative benign lesions, and 0.644 for cancer (ductal carcinoma-in-situ and inv asive). A specificity of 55% was obtained at 90% sensitivity for women with palpable lesions when a discriminant based on age and the depola risation index was used. Interpretation This new modality may have dia gnostic value, especially in reducing the number of unnecessary diagno stic tests among women with inconclusive findings on physical examinat ion. Understanding and control of the biological variability of these electrical phenomena will be important in the improvement of this test . Studies in populations with a lower cancer prevalence are needed to assess further the diagnostic value of this approach.