Frequency of diagnosis of cancer or high-risk lesion at operation for pathologic nipple discharge

Background. Pathologic nipple discharge is managed customarily with diagnostic subareolar duct excision. We evaluated for features predictive of malignancy to identify cases where operation might be avoided. Methods. We studied 311 consecutive subareolar duct excisions for pathologic nipple discharge from January 2008 to July 2014. chi(2) tests were used to test for associations with final pathology. Results. In 27 cases, cancer was diagnosed preoperatively. Among the remaining 284, 26 (9%) were diagnosed with cancer and 8 (3%) with atypia at operation. At greatest risk of upstage to cancer were patients with prior ipsilateral breast cancer (3/8; 38%), BRCA mutation (2/3; 67%) or atypia on core needle biopsy (CNB; 3/8 [38%]). Excluding these patients lowered cancer and atypia upstages (7% [18/265] and 3% [7/265]), with bloody (versus serous) discharge (P = .001), and focal imaging abnormality (P = .02), the strongest risk factors. Serous discharge and either normal imaging or a benign CNB had a 1.3% cancer upstage rate. Conclusion. Despite contemporary imaging, pathologic nipple discharge upstage rates to malignancy and atypia remain high, especially with prior ipsilateral breast cancer, BRCA mutation, or atypia on CNB. Absent these risk factors, patients with serous discharge and a benign CNB or normal imaging (cancer risk <2%) may be considered for nonoperative management.