A comparative analysis of diagnostic values of high-frequency ultrasound and fiberoptic ductoscopy for pathologic nipple discharge

BACKGROUND: This study aimed to compare the diagnostic accuracy of high-frequency ultrasound (HFUS) and fiberoptic ductoscopy (FDS) for pathologic nipple discharge (PND). METHODS: HFUS and FDS were conducted in 210 patients with PND (248 lesions) treated at our hospital. The diagnostic accuracy of these two methods was compared using pathological diagnosis as the standard. RESULTS: Among 248 lesions, 16 and 15 of 16 malignant lesions were accurately diagnosed by HFUS and FDS, respectively. Of 232 benign lesions, 183 and 196 cases were accurately diagnosed by HFUS and FDS, respectively. The sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of HFUS in diagnosis of intraductal lesions were 84.36% (95% CI 79.26–88.39%), 60% (95% CI 23.07–92.89%), 96.03% (95% CI 96.55–99.83%), and 7.31% (95% CI 2.52–19.4%) respectively. The sensitivity, specificity, PPV, and NPV of FDS in diagnosis of intraductal lesions were 86.83% (95% CI 82.00–90.52%), 100% (95% CI 56.55–100%), 100% (95% CI 98.21–100%), and 13.51% (95% CI 5.91–27.98%) respectively. Diagnostic accuracy rates of HFUS and FDS were 83.87% (208/248) and 85.08% (211/248), respectively, exhibiting no statistically differences (χ(2) = 0.80, P > 0.05). The accuracy of HFUS combined with FDS was 93.14% (231/248), showing statistically differences (χ(2) = 10.91, P < 0.05). CONCLUSIONS: Both HFUS and FDS demonstrated high diagnostic values for PND. HFUS has the advantage of non-invasive for nipple discharge with duct ectasia, exhibited good qualitative and localization diagnostic values. It is the preferred evaluation method for patients with nipple discharge. When HFUS cannot identify the cause of PND, FDS can be considered.