Sydney Breast Imaging Accuracy Study: Comparative Sensitivity and Specificity of Mammography and Sonography in Young Women with Symptoms

Abstract
OBJECTIVE. We examined the age-specific sensitivity and specificity of mammography and sonography in symptomatic women to determine the age below which sonography may be the more accurate imaging test, which may guide the choice of initial breast imaging examination based on the woman's age.MATERIALS AND METHODS. Four hundred eighty subjects were sampled from all women consecutively attending a symptomatic breast clinic between 1994 and 1996 and ranging in age from 25 to 55 years. We included all 240 women shown to have breast cancer (thus avoiding selection bias) and 240 age-matched women shown not to have cancer. Mammograms and sonograms were prospectively interpreted independently and without knowledge of age by two radiologists in a blinded manner, with a third radiologist arbitrating disagreements. Sensitivity and specificity of each imaging test in relation to age were examined using logistic regression modeling, and accuracy was compared using the chi-square test for paired proportions.RESULTS. Sen...