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 earlymorphologic and physiologic changes such as cell swellingcan be obtained.Aims: We investigated the correlation between the prognosticfactors 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 betweenSeptember 2012 and September 2013, who underwent dynamicbreast MRI before or after biopsy and whose biopsyresults were determined as malignant, were included in ourstudy. Before the dynamic analysis, DWI sequences weretaken. ADC relationship with all prognostic factors wasinvestigated. Pearson correlation test was used to comparethe numerical data, while Spearman correlation and Fisherexact tests were used to compare the categorical data. Theadvanced relationships were evaluated with linear regressionanalysis and univariate analysis. The efficiency of theparameters was evaluated using ROC analysis. The significancelevel (P) was accepted as 0.05.Results: In total, 41 female patients with an average age of49.4 years (age interval 21-77) and 44 lesions were includedinto the study. In the Pearson correlation test, no statisticallysignificant difference was determined between ADC andthe patient's age and tumor size. In the Spearman correlationtest, a statistically significant difference was determinedbetween nuclear grade (NG) and ADC (r=-0.424, p=0.04);no statistically significant correlation was observed betweenthe other prognostic factors with each other and ADC values.In the linear regression analysis, the relationship of NGwith ADC was found to be more significant alone than whencomparing all parameters (corrected r2=0.196, p=0.005).Further evaluations between the NG and ADC correlationwere carried out with ROC analysis. A statistically significantdifference was determined when NG 1 separately wascompared with NG 2 and 3 (p=0.03). A statistically significantdifference was also determined (p=0.05) in the comparisonof NG 1 with only NG 3. No statistically significantdifference was determined when NG 2 separately was comparedwith NG 1 and NG 3 and when NG 3 separately wascompared with NG 1 and 2 (p=0.431, p=0.097),Conclusion: We found that ADC values obtained by breastDWI showed a higher correlation with the NG of breastcancer, which is an important factor in the patient's treatment.Predictions can be made about NG by analyzing theADC values. Additional studies are needed, however, andthe ADC value of the lesion can be used as a prognostic factorproving the aggressiveness.