The hyperechoic zone around breast lesions - an indirect parameter of malignancy.

PURPOSE

To evaluate an irregular perilesional hyperechoic zone as a potential criterion of malignancy on breast ultrasound and to test whether this zone correlates with perilesional T2 hyperintensity on magnetic resonance imaging (MRI).

MATERIALS AND METHODS

A total of 137 patients (85 malignant lesions, 52 benign lesions) who underwent breast ultrasound with a 9 - 14 MHz linear broad-spectrum transducer and consecutive ultrasound-guided biopsy were included. All patients additionally underwent breast MR imaging with dedicated breast coils at 1.5 T. The protocol included a T2-weighted sequence. Perilesional hyperechoic and T2 hyperintense areas were measured by planimetry using the slice showing maximum extension of this area. The sensitivity and specificity of the perifocal area for identifying breast malignancy were determined using ROC analysis. Correlation was assessed using Pearson analysis.

RESULTS

The presence of a hyperechoic zone identified malignancy with a sensitivity of 87% and a specificity of 81%. Additionally, there was a highly significant correlation of the size of the hyperechoic zone with the degree of tumor differentiation (p = 0.002) as well as with the mib-1 proliferation index (p = 0.006) and lymphangio-invasion (p = 0.02). No significant correlation was found between the hyperchoic zone and the T2 hyperintense zone on MRI (R2 = 0.16).

CONCLUSION

A hyperechoic zone surrounding breast lesions may serve as an additional sonomorphologic criterion of malignancy. Yet, it does not seem to correlate with edema on MRI.