SENSITIVITY AND SPECIFICITY OF OCCULT BLOOD TESTING IN SYMPTOMATIC SINGLE DUCT NIPPLE DISCHARGE TO DETECT DUCTAL CARCINOMA

Abstract

Introduction: Testing asymptomatic nipple discharge in women for occult hemoglobin to predict the presence of ductal carcinoma remains controversial. The purpose of this study is to describe the sensitivity and specificity of occult blood testing in patients with asymptomatic single duct nipple discharge.

Methods: Data was collected ambispectively during a 7 year period. All patients with asymptomatic single duct nipple discharge were included in this study. The results of occult blood testing were correlated with the histopathological results after microductectomy.

Results: All 63 patients were female. They underwent mammography and ultrasound examination

of the discharging breast which were normal in all cases. The average follow up period was 2 years (0.5 to 5 years). Occult blood was positive in 37 (58.8 %) patients and negative in 26 (41.2 %) patients. Histopathological diagnosis was ductal ectasia in 30 % (n=18), intraductal papilloma in 44 % (n=28), granuloma 2 % (n=1), normal 12 % (n=8) and ductal carcinoma in situ 12 % (n=8). The most frequent cause for positive occult blood was ductal papilloma (n=23) followed by ductal ectasia (n=13). The sensitivity of the test was 87.5 % and specificity 45.4 %, with a positive predictive value of 18.9 % and a negative predictive value of 96.1 % and an Odds ratio of 5,833.

Discussion: Positive occult blood testing can help to predict the presence of either in situ or invasive ductal carcinoma in the absence of other symptoms. We recommend, however, an approach based on clinical examination, radiological testing and risk factor analysis to decide which patients require microductectomy to exclude the presence cancer definitively.