Diffusion Weighted MR Imaging of Breast and Correlation of Prognostic Factors in Breast Cancer

Abstract

Background: Through Diffusion Weighted Imaging (DWI), information related to early molecular changes, changes in the permeability of cell membranes, and early morphologic and physiologic changes such as cell swelling can be obtained. Aims: We investigated the correlation between the prognostic factors of breast cancer and apparent diffusion coefficient (ADC) in DWI sequences of malignant lesions. Study Design: Retrospective cross-sectional study. Methods: Patients who were referred to our clinic between September 2012 and September 2013, who underwent dynamic breast MRI before or after biopsy and whose biopsy results were determined as malignant, were included in our study. Before the dynamic analysis, DWI sequences were taken. ADC relationship with all prognostic factors was investigated. Pearson correlation test was used to compare the numerical data, while Spearman correlation and Fisher exact tests were used to compare the categorical data. The advanced relationships were evaluated with linear regression analysis and univariate analysis. The efficiency of the parameters was evaluated using ROC analysis. The significance level (P) was accepted as 0.05. Results: In total, 41 female patients with an average age of 49.4 years (age interval 21-77) and 44 lesions were included into the study. In the Pearson correlation test, no statistically significant difference was determined between ADC and the patient's age and tumor size. In the Spearman correlation test, a statistically significant difference was determined between nuclear grade (NG) and ADC (r=-0.424, p=0.04); no statistically significant correlation was observed between the other prognostic factors with each other and ADC values. In the linear regression analysis, the relationship of NG with ADC was found to be more significant alone than when comparing all parameters (corrected r2=0.196, p=0.005). Further evaluations between the NG and ADC correlation were carried out with ROC analysis. A statistically significant difference was determined when NG 1 separately was compared with NG 2 and 3 (p=0.03). A statistically significant difference was also determined (p=0.05) in the comparison of NG 1 with only NG 3. No statistically significant difference was determined when NG 2 separately was compared with NG 1 and NG 3 and when NG 3 separately was compared with NG 1 and 2 (p=0.431, p=0.097), Conclusion: We found that ADC values obtained by breast DWI showed a higher correlation with the NG of breast cancer, which is an important factor in the patient's treatment. Predictions can be made about NG by analyzing the ADC values. Additional studies are needed, however, and the ADC value of the lesion can be used as a prognostic factor proving the aggressiveness.

Is there any relationship between adc values of diffusion-weighted imaging and the histopathological prognostic factors of invasive ductal carcinoma?

“…If a consensus is to be identified, it is that tumour size is almost unanimously shown to not correlate with ADC values. 29,33,40,41 We believe these contrasting results may be explained by differences in B values, ROI area and device magnetic power. In Table 3, we have provided the results and technical parameters of various studies.…”

“…27,38,39 An almost equal number of studies also report contrasting results on the same factors. 33,40,41 Furthermore, some studies that simultaneously show a relationship with a specific factor, report drastically different results in other factors. If a consensus is to be identified, it is that tumour size is almost unanimously shown to not correlate with ADC values.…”

“…Although various studies have found Ki-67 and ADC to be correlated, 32,34 the correlation coefficients are low and several studies show conflicting findings. 37,41 This may be because the ADC value is derived from a larger portion of tissue, while the Ki-67 index is a very local representation of the tumour tissue. Another explanation may be that, although increased Ki-67 index represents an increase in cell multiplication, this may not directly translate to increased density of cells due to the varying density of breast tissue among patients.…”

Evaluation of Short-Term Efficacy of Concurrent Chemoradiotherapy in Primary Fallopian Tube Carcinoma by Diffusion-Weighted Imaging: A Retrospective Study

“…The region of interest (ROI) was set as the largest and clearest layer of the lesion. Each ROI was measured 3 times, and the mean ROI was taken as the general ADC value [13]. MR-DWI was conducted 1 day before and 1 month after CCRT, and the results are shown in figure 1.…”

Combining multiparametric MRI with receptor information to optimize prediction of pathologic response to neoadjuvant therapy in breast cancer: preliminary results

“…The rate of diffusion in tissue is described by an apparent diffusion coefficient (ADC), which can be measured by established DW-MRI methods. [18][19][20][21] In controlled experiments, the variations in ADC have been shown to correlate inversely with tissue cellularity. [22][23][24][25][26] In DCE-MRI, images are acquired before and after a contrast agent is injected into a peripheral vein.…”