Variations in Abnormal Nipple Discharge Management in Women- a Systematic Review and Meta-analysis

Abstract

Nipple discharge accounts for 5% of referrals to breast units; breast cancer in image negative nipple discharge patients varies from 0 to 21%. This systematic review and meta-analysis determined variability in breast cancer rates in nipple discharge patients, diagnostic accuracy of modalities and surgery rates. An ethically approved meta-analysis was conducted using databases PubMed, EMBASE, and Cochrane Library from January 2000 to July 2015. For the breast cancer rates’ review, studies were excluded if no clinical follow-up data was available. For the diagnostic accuracy meta-analysis, studies were excluded if there was no reference standard, or the number of true and false positives and negatives were not known. Pooled sensitivities were determined using Mantel-Haenszel method. For the surgery rates’ review, only studies with consecutive nipple discharge patients were included. Average risk of having a breast cancer is 10.2% in nipple discharge patients. Most studies reported an age threshold of 50 above which breast cancer risk greatly increases. Pooled sensitivities of ultrasound, mammogram, mammogram and ultrasound, breast MRI, conventional galactography, smear cytology, ductal lavage cytology and ductoscopy were 0.64, 0.34, 0.65, 0.81, 0.75, 0.37, 0.49 and 0.82 respectively. Average surgery rate was 43.4%. Malignancy rate of 10.2% indicates the need to continue surgery, especially for patients aged over 50. Patients below 50, in the absence of risk factors such as family history, can be managed conservatively with close follow up.