Objective:

To assess the value of magnetic resonance imaging (MRI) in differential diagnosis of malignant papillary lesions and other malignant lesions of the breas

t.

Methods:

A total of 590 patients with malignant breast lesions were retrospectively analyzed. All patients underwent breast MRI and confirmed by pathological examination. The MRI findings were categorized according to Breast Imaging Reporting and Data System (BI-RADS) 2013 edition. Time-signal intensity curve (TIC) and apparent diffusion coefficient (ADC) were achieved from the 1.5T Siemens MAGNETOM Aera workstation

which were used in differential diagnosis of breast lesions.

Results:

The malignant papillary lesions tended to present as non-mass enhancement

and the other malignant lesions tended to present as mass. Malignant papillary lesions tended to locate in the retroareolar regions more than those in other malignant group. All the malignancies tend to appear irregular shaped

1-5 cm in diameter

heterogeneous enhanced. In the non-mass enhancement lesions

malignant papillary lesions tended to appear segmental distribution

other malignant lesions tended to appear regional or diffuse distribution. Ductal dilation was more common in malignant papillary lesions than other malignant lesions. The solitary proportion ＜25% is more common in malignant papillary lesions than the other malignant lesions. All the malignant lesions tend to appear wash-out curve. Mean ADC was ［(0.940.23)10

-3

mm

2

/s vs (0.860.21)10

-3

mm

2

/s］in the group of malignant papillary lesions and other malignant lesions respectively. The best discriminative value of ADC was 1.0410

-3

mm

2

/s and the area under curve was 0.620. The sensitivity

specificity and accuracy were 88.7%

35.0% and 82.7%

respectively.

Conclusion:

The location of the mass

the distribution of the non-mass enhancement

ductal dilation

solid proportion and ADC values which have differential diagnosis of malignant papillary lesions and the other malignancies.