To explore the diagnostic value of mammary ductoscopy and breast ultrasonography in intraductal space-occupying lesions with nipple discharge.

The clinical data of 133 patients with nipple discharge in the Department of Endocrine and Breast Surgery, the First Affiliated Hospital of Chongqing Medical University from January 2017 to February 2018 were retrospectively analyzed. The application of mammary ductoscopy and breast ultrasonography was analyzed for the diagnosis of intraductal space-occupying lesions in nipple discharge patients. Paired χ² test was used to compare the detection rates of intraductal space-occupying lesions between two methods and analyze the sensitivity of mammary ductoscopy and breast ultrasonography in the diagnosis of intraductal papilloma. Fisher exact probability test were used to compare the malignancy rate of intraductal space-occupying lesions between two groups.

In 133 patients, 63 patients underwent duct excision, 4 minimal invasive surgery of breast nodes, 2 radical mastectomy after the malignancy was confirmed (one case by core-needle biopsy and the other by lumpectomy). Fifty-three patients underwent no surgery and 11 patients were lost to follow-up. In 65 patients receiving conventional surgery, postoperative pathology revealed malignant breast tumor in 4 patients, intraductal papilloma in 57 and breast hyperplasia in 4. The detection rate of intraductal space-occupying lesions by mammary ductoscopy was 57.1% (76/133), significantly higher in 24.8% (33/133) by breast ultrasonography (χ²=31.339, P<0.001). The sensitivity of mammary ductoscopy was significantly higher than that of breast ultrasonography in the diagnosis of intraductal papilloma [93.0%(53/57) vs 42.1%(24/57), χ²=33.652, P<0.001). Among the patients with intraductal space-occupying lesions indicated by mammary ductoscopy, the patients with breast mass or bleeding of space-occupying lesions had a significantly higher incidence of malignancy compared with the patients without breast mass or bleeding [3/13 vs 2.3% (1/44), P=0.034].

Mammary ductoscopy is superior in the diagnosis of intraductal space-occupying lesions and can be used as a routine examination for patients with nipple discharge. For patients with intraductal space-occupying lesions associated with breast mass or tumor hemorrhage, surgical resection should be performed to confirm the diagnosis.