RESUMO
BACKGROUND: Electrical impedance scanning (EIS) measures changes in breast tissue associated with breast cancer (Br-Ca) development. The T-Scan(tm2000 (ED is designed to use EIS to identify women ages 30-39 with elevated risk of breast cancer (i.e., T-Scan+ women). AIM: To estimate the relative probability of breast cancer in a T-Scan+ woman compared to a randomly selected young woman. METHODS: A prospective, two-cohort trial was conducted in pre-menopausal women. The Specificity (S(p))-Cohort evaluated T-Scan specificity in 1,751 asymptomatic women ages 30-39. The Sensitivity)S(n))-Cohort evaluated T-Scan sensitivity in 390 women ages 45-30 scheduled for biopsy. Specificity, sensitivity, and conservative estimate of disease prevalence were used to calculate relative probability. RESULTS: In the S(p)-Cohort, 93 of 1,751 women were T-Scan+ (S(p) = 94.7%; 95% CI: 93.7-95.7%). In the S(n)-Cohort, 23 of 87 biopsy-proven cancers were T-Scan+ (S(n) = 26.4%; 95% CI: 17.4-35.4%). Given S(p) = 94.7%, S(n) = 26.4% and prevalence of 1.5 cancers/1,000 women (ages 30-39), the relative probability of a T-Scan+ woman having Br-Ca is 4.95: (95% CI: 3.16-7.14). CONCLUSION: EIS can identify a subset of young women with a relative probability of breast cancer almost five times greater than in the population of young women at-large. T-Scan+ women have a sufficiently high risk of Br-Ca to warrant further surveillance or imaging.