The malignant possibility of intraductal lesions with different ultrasound manifestations under different age and nipple discharge status.

Background: Due to their heterogeneous nature, the diagnosis and treatment of intraductal lesions are controversial. It is not yet clear whether biopsy or open surgery should be recommended for all women with intraductal lesions. We aimed to identify the risk factors of intraductal lesions, which are often malignant.

Methods: We retrospectively investigated the relationship between patient age, nipple discharge, ultrasound (US) findings, and the final pathology outcomes of intraductal lesions to identify the variables associated with malignancy.

Results: A total of 1,058 patients with 1,069 pathologically proven intraductal lesions were included in this study. The age of the patients ranged from 18 to 86 years (mean age: 46.8±11.6 years). The pathologic findings of the 1,069 lesions revealed 288 cases of duct ectasia, 642 cases of intraductal papilloma (IP), 45 cases of IP with ductal carcinoma in situ (DCIS), and 94 cases of solid papillary carcinoma (SPC). An alluvial diagram of patient age, nipple discharge, US findings, and pathologic results showed that the relationship among these variables is complicated and intertwined. In general terms, the lesions were more likely to be malignant in older patients and those with bloody nipple discharge. The US subtypes I-III had similar rates of malignancy; however the rate of malignancy of the US subtype V differed. Bloody nipple discharge and an age ≥60 years were identified as independent predictors of malignancy.

Conclusions: Our findings may guide doctors in risk stratification and in making decisions for patients with intraductal lesions.