Evaluating the risk of underlying malignancy in patients with pathologic nipple discharge.

Most pathologic nipple discharge (PND) is benign, but duct excision has been advised to exclude malignancy. To identify factors associated with malignancy, we reviewed 280 patients with PND at our institution from 2004 to 2014. In 49 cases, malignancy was found. These patients more often had palpable masses (39% vs 11%, P < .001) and abnormal imaging (94% vs 75%, P = .004). On multivariable analysis, age, palpable mass, and abnormal imaging were independently associated with malignancy. Among 48 patients with PND but no other clinical/imaging abnormalities, only 1 malignancy, a small ductal carcinoma in situ, was identified. Observation may be reasonable for these select patients.