Prediction of invasive breast cancer using shear-wave elastography in patients with biopsy-confirmed ductal carcinoma in situ.

OBJECTIVES

To investigate whether mass stiffness measured by shear-wave elastography (SWE) can predict the histological upgrade of ductal carcinoma in situ (DCIS) confirmed through ultrasound (US)-guided core needle biopsy (CNB).

METHODS

The institutional review board approved this study and informed consent was waived. A database search revealed 120 biopsy-confirmed DCIS in patients who underwent B-mode US and SWE prior to surgery. Clinicopathologic results, B-mode findings, size on US, and mean and maximum elasticity values on SWE were recorded. Associations between upgrade to invasive cancer and B-mode US findings, SWE information, and clinical variables were assessed using univariate, multivariate logistic regression, and multiple linear regression analysis.

RESULTS

The overall upgrade rate was 41.7 % (50/120). Mean stiffness value (P = .014) and mass size (P = .001) were significantly correlated with histological upgrade. The optimal cut-off value of mean stiffness value, yielding the maximal sum of sensitivity and specificity, was 70.7 kPa showing sensitivity of 72 % and specificity of 65.7 % for detecting invasiveness. Qualitative elasticity colour scores were significantly correlated with the histological upgrade, mammographic density, and B-mode category (P < .04).

CONCLUSION

Mean stiffness values evaluated through SWE can be utilized as a preoperative predictor of histological upgrade to invasive cancer in DCIS confirmed at US-guided needle biopsy.

KEY POINTS

• Higher stiffness values were noted in invasive cancer than DCIS. • Qualitative SWE colour scores significantly correlated with the histological upgrade. • Qualitative SWE colour scores had excellent interobserver agreement.