Breast MRI using the VIBE sequence: clustered ring enhancement in the differential diagnosis of lesions showing non-masslike enhancement.
OBJECTIVE
The purpose of this study was to assess the frequency of a finding in which minute ring enhancements are clustered (defined as clustered ring enhancement) in lesions showing non-masslike enhancement and to evaluate the clinical usefulness of this sign, in addition to that of the BI-RADS MRI descriptors, in the differentiation between benign and malignant lesions.


METHODS
Retrospective review was performed of 61 consecutive lesions showing non-masslike enhancement. MRI was performed on a 1.5-T system using the volumetric interpolated breath-hold examination (VIBE) sequence. The kinetic parameter was visually assessed as follows: washout, plateau, and persistent.


RESULTS
The most frequent morphologic finding among the malignant lesions was heterogeneous internal enhancement (69%) (p = 0.003), followed in frequency by segmental distribution (54%) (p < 0.001); whereas, stippled internal enhancement was the most frequent finding in benign lesions (50%) (p < 0.001). The presence of clustered ring enhancement was found in 63% of the malignant lesions and only 4% of the benign lesions (p < 0.001). The features with the highest positive predictive value for malignancy were a segmental distribution (100%), clustered ring enhancement (96%), and a washout pattern (94%). The specificity of clustered ring enhancement was 96% (25/26). In cases showing focal and regional enhancement, the combination of clumped internal architecture and clustered ring enhancement showed a statistically significant association with malignant lesions (p < 0.001).


CONCLUSIONS
Clustered ring enhancement is thought to be a useful sign to differentiate between benign and malignant lesions, in addition to the BI-RADS MRI descriptors.
Tozaki
Mitsuhiro
M
Division of Diagnostic Imaging, Breast Center, Kameda Medical Center, 929 Higashi-cho, Kamogawa, Chiba, Japan 296-8602. e-tozaki@keh.biglobe.ne.jp
Igarashi
Takao
T
Fukuda
Kunihiko
K
D000328:Adult; D000368:Aged; D001941:Breast Diseases / Q000473:pathology*; D001943:Breast Neoplasms / Q000473:pathology*; D002277:Carcinoma / Q000473:pathology*; D003937:Diagnosis, Differential; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008875:Middle Aged; D012119:Respiration; D012189:Retrospective Studies