Objective:

To investigate the ultrasonographic and pathological features

of pure ductal carcinoma

in situ

（DCIS）.

Methods:

The ultrasonographic features and pathological features of 144 patients with DCIS confirmed by surgery and pathology in the First Affiliated Hospital of Nanjing Medical University from Oct. 2016 to Apr. 2019 were retrospectively analyzed. According to the characteristics of ultrasound images

it can be divided into six categories: Type Ⅰ simple mass

Type Ⅱ glandular disorder

Type Ⅲ ductal dilatation

Type Ⅳ ductal dilatation with hypoechoic mass

Type Ⅴ simple calcification

Type Ⅵ no positive finding by ultrasound.

Results:

Type Ⅰ 95 cases (66.0%)

Type Ⅱ 21 cases (14.6%)

Type Ⅲ 7 cases (4.9%)

Type Ⅳ 7 cases (4.9%)

Type Ⅴ 12 cases (8.3%)

Type Ⅵ 2 cases (1.4%). The diagnosis was 83.2% (79/95)

76.2% (16/21)

0.0% (0/7)

42.9% (3/7)

83.3% (10/12)

0.0% (0/2). Seventy-five cases (52.1%) showed calcification on ultrasound images. The diagnosis accuracy was 86.7% (65/75)

which was higher than non-calcification group (

²

=11.362，

P

=0.001). Ninety-nine cases（68.8%）showed blood flow classification Ⅱ and Ⅲ on ultrasound images. The diagnosis accuracy was 86.9% (86/99)

which was higher than low blood flow classification group (

²

=23.801，

P

=0.000). Pathological features showed that 71 cases (49.3%) were of low and middle grade

73 cases (50.7%) were ofhigh grade

50 cases (34.7%) were of Luminal A type

63 cases (43.8%) were of Luminal B type

29 cases (20.1%) were of human epidermal growthfactor receptor 2 (HER2) type

and 2 cases (1.4%) were of tri-negative type.

Conclusion:

Mass type is the most common ultrasonographic manifestation of DCIS. The diagnostic accuracy of DCIS by ultrasound is related to its ultrasonographic features. Calcification and the richness of blood flow are important factor on ultrasound images. The pathological features of DCIS are closely related to calcification. Ultrasound plays an important role in clinical

diagnosis of DCIS.