Single-duct nipple discharge: How concerned should we be?

Abstract

58 Background: Nipple discharge has a known association with breast cancer, but determining which cases to identify as being at high risk is a complex and controversial task for the clinician. The current policy at West Hertfordshire Hospitals Trust is to offer microdochectomies to all women who present with unilateral single duct discharge, dominant duct discharge or persistent duct discharge and negative cytology and pre-operative imaging. The aim of this study is to determine if a more discriminative approach might be applied to women who present with nipple discharge. Methods: All patients who underwent a microdochectomy over a 4-year period (2006-2011) were assessed. Patient demographics, characteristics, presenting complaint, pre-operative imaging, and pathology results were analysed. Results: Of the 122 patients analysed in this study, only 7 (5.74%) were diagnosed with malignant carcinoma: 4 patients had DCIS; 3 patients had DCIS and IDC. Of these, 2 had bloodstained nipple discharge. Another two women were diagnosed with papillary carcinoma; only one of them presented with bloodstained nipple discharge, although both had single duct discharge only. 42 cases of mammary duct ectasia (34.43%) and 52 cases of papilloma (42.62%) were found. All women with malignant diagnoses were over the age of 55. Although 47 women (38.52%) presented with a history of blood-stained discharge, only 17 of this cohort (36.17%) had positive cytology – one of whom was diagnosed with multifocal intermediate-grade DCIS. The other 16 women were diagnosed with papillomas, duct ectasia, and benign breast disease. Of those 30 women who presented with a history of bloodstained discharge and had negative cytology, only two were diagnosed with carcinoma (DCIS + IDC and papillary Ca); of those 17 with no recorded bloodstained discharge but positive cytology there were no malignant diagnoses. Conclusions: Microdochectomy performed for nipple discharge results in a low rate of malignancy on excision. Our results from this study correspond with other microdochectomy series. It would appear that a cytological diagnosis is an equivocal discriminator for cancer at best. Further work on a prospective study will help to differentiate patient groups who would most benefit from surgical intervention.