Diffusion-Weighted Imaging of Breast Cancer: Correlation of the Apparent Diffusion Coefficient Value with Pathologic Prognostic Factors

Abstract

Objective: Th aim was to evaluate relationship between apparent diffsion coeffient (ADC) values with pathologic prognostic factors in breastcarcinoma (BC).Materials and Methods: 83 patients were enrolled in this study. Prognostic factors included age, tumor size, expression of estrogen receptor (ER)and progesterone receptor (PR), human epidermal growth factor receptor 2 (HER2), nuclear grade (NG), lymph node involvement and histologictype. Th relationship between ADC and prognostic factors was determined using Independent sample t-test, ANOVA, Pearson correlation and relativeoperating characteristics (ROC) analysis.Results: Thre was no signifiant diffrence between ADC and prognostic factors, including age, tumor size, ER, HER2 and histologic type. Th PRpositive tumors (p=0.03) and axillary lymph node involvement (p=0.000) showed a signifiant association with lower ADC values. Th ADC values weresignifiantly lower in high-grade tumors than low-grade tumors (p=0.000). ROC analysis showed an optimal ADC threshold of 0.66 (×10-3 mm2/s) fordiffrentiating low-grade tumors from high-grade tumors (sensitivity, 85.5%; specifiity, 81%; area under curve, 0.90).Conclusion: Th lower ADC values of BC were signifiantly associated with positive expression of PR, LN positivity and high-grade tumor. Especially,ADC values were valuable in predicting NG subgroups.