Background: The aim of this study was to investigate the MR mammography (MRM), digital mammography (DM), and ultrasound (US) findings of solid papillary carcinoma (SPC) of breast and to raise awareness of this rare breast tumor.
Material and methods: Thirty patients diagnosed with breast SPC (age range, 21-72; mean age, 60.27 years) from January 2013 to August 2015 were enrolled. Their clinical presentation and MRM, DM, and US findings were retrospectively reviewed. All patients underwent both MRM and US, and 20 of them underwent DM. The research primarily investigated MRM features correlated with clinicopathological characteristics.
Results: Of all the patients, 13 were pure SPC in suit, whereas 17 were microinvasive SPC. The detection rates of US, DM, and magnetic resonance imaging for SPC were 30%, 50%, and 100%, respectively, and there were no specific imaging features on DM and US. The most common MRM appearances were located in the retroareolar area (16/30, 53.34%) with T2WI hyperintensity (24/30, 80%) and ductal ectasia (18/30, 60%). Non-mass enhancement of a linear or segmental distribution (17/18, 94.44%) together with clumped enhancement (12/18, 66.66%) and mass with a rim (6/12, 50%) or heterogeneous (6/12, 50%) enhancement were 2 of the typical enhancement features of SPC. Compared with pure SPC, SPC with microinvasive showed larger size of the lesion (t = 1.083, P = 0.026).
Conclusion: Although SPC was difficult to detect in both DM and US, MRM gave better detection of this rare tumor. The MRM characteristics of SPC were distinct and highly similar to its clinicopathological features.