Ultrasound Breast Elastographic Evaluation of Mass-Forming Ductal Carcinoma-in-situ with Histological Correlation - New Findings for a Toothpaste Sign.
BACKGROUND
It is unclear as to whether the size ratio elastographic technique is useful for assessing ultrasound- detected ductal carcinoma-in-situ (DCIS) masses since they commonly lack a significant desmoplastic reaction. The objectives of this study were to determine the accuracy of this elastographic technique in DCIS and examine if there was any histopathological correlation with the grey-scale strain patterns.


METHODS
Female patients referred to the radiology department for image-guided breast biopsy were prospectively evaluated by ultrasound elastography prior to biopsy. Histological diagnosis was the gold standard. An elastographic size ratio of more than 1.1 was considered malignant. Elastographic strain patterns were assessed for correlation with the DCIS histological architectural patterns and nuclear grade.


RESULTS
There were 30 DCIS cases. Elastographic sensitivity for detection of malignancy was 86.7% (26/30). 10/30 (33.3%) DCIS masses demonstrated predominantly white elastographic strain patterns while 20/30 (66.7%) were predominantly black. There were 3 (10.0%) DCIS masses that showed had a co-existent bull's-eye sign and 7 (23.3%) other masses had a co-existent toothpaste sign, a strain pattern that has never been reported in the literature. Four out of 4/5 comedo DCIS showed a predominantly white strain pattern (p=0.031) while 6/7 cases with the toothpaste sign were papillary DCIS (p=0.031). There was no relationship between the strain pattern and the DCIS nuclear grade.


CONCLUSIONS
The size ratio elastographic technique was found to be very sensitive for ultrasound-detected DCIS masses. While the elastographic grey-scale strain pattern should not be used for diagnostic purposes, it correlated well with the DCIS architecture.
Diagnostic Radiology, Radiology, Singapore General Hospital, Singapore E-mail : lester.leong.c.h@sgh.com.sg.
Lester Chee Hao
LC
Leong
Llewellyn Shao-Jen
LS
Sim
Ana Richelia
AR
Jara-Lazaro
Puay Hoon
PH
Tan
D001940:Breast / Q000000981:diagnostic imaging / Q000473:pathology*; D001943:Breast Neoplasms / Q000000981:diagnostic imaging / Q000473:pathology*; D018270:Carcinoma, Ductal, Breast / Q000000981:diagnostic imaging / Q000473:pathology*; D002285:Carcinoma, Intraductal, Noninfiltrating / Q000000981:diagnostic imaging / Q000473:pathology*; D054459:Elasticity Imaging Techniques / Q000379:methods*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D009367:Neoplasm Staging; D011379:Prognosis; D016217:Ultrasonography, Mammary / Q000379:methods*