Keywords:
Breast, MR-Diffusion/Perfusion, Diagnostic procedure
Authors:
A. SPEZZACATENE, M. TONUTTI, F. GIUDICI, F. Zanconati, M. A. Cova; Trieste/IT
DOI:
10.26044/ecr2019/C-2197
Results
Nineteen (35.8%) out of 53 breast lesions were malignant (12 of 33 masses and 7 of 17 lesions with non-mass enhancement) (Table 1).
Among malignant lesions with mass enhancement,
the prevalent histologic subtype was invasive ductal carcinoma (75%),
while among lesions with non-mass enhancement the most frequent histotype was invasive lobular carcinoma (42.8%).
The median ADC was significantly lower for malignant than for benign lesions (median ADC value of 0.89 × 10−3 mm2/s versus 1.03 × 10−3 mm2/s respectively; p=0.04) (Fig.
1).
Stratifying the analysis of ADC values on the basis of the type of enhancement (mass/non mass) and size of lesions,
the median ADC was significantly lower for malignant lesions (Fig.
2) than for benign lesions (Fig.
3) with mass enhancement (mean difference 0.15 × 10−3 mm2/s; p=0.05) but there were no significant differences between benign and malignant lesions with non-mass enhancement and no relation between ADC value and lesion size (Table 2).
ROC (receiver operating characteristics) analysis was used to evaluate the diagnostic performance of ADC thresholds for differentiating benign and malignant breast lesions.
The area under the receiver operating characteristics curve (AUC) was 0.66 (Fig.
4),
with an ADC threshold for differentiating benign and malignant lesions of 0.9×10−3 mm2/s resulting in a diagnostic sensitivity of 58% and specificity of 79%.
The specificity of quantitative DWI was higher for the characterization of mass lesions than for lesions with non-mass enhancement (86% versus 50% respectively; p=0.07),
while it was not significantly different among small (≤10mm) and large (>10 mm) lesions.