Four Different Apparent Diffusion Coefficient Measurement Methods in Breast Masses.

Abstract

To compare the effect of different quantification methods of ADC values in the evaluation of breast lesions and compare contralateral normal breast tissue ADC value by calculating ADC ratios. Descriptive study. Place and Duration of the Study: Sisli Etfal Training and Research Hospital, Turkey, between February 2019 and December 2020. Two hundred and forty-six breast MRI scans with DWI of the patients with biopsy proven unilateral breast lesions were studied. ADC measurements were done by placing ROI. Two ADC values and two ADC ratios were obtained by different methods. The diagnostic accuracies of these four techniques were compared. Mean ADC values and ratios of benign and malignant lesions were statistically significant in all of four methods to quantify ADC (p< 0.001). Highest positive value and negative predictive value, and diagnostic accuracy rates were achieved when the most restricted part ADC value was calculated. However; highest sensitivity rate and negative predictive value were achieved by calculating the ratio of darkest point ADC to contralateral breast tissue. Positive predictive value, negative predictive value, and diagnostic accuracy rate of calculated ADC values and ratios were higher when lesions were larger than the mean size (3.15 mm2). Highest diagnostic accuracy rate was obtained with most restricted part ADC value. Obtained ratios by calculating contralateral breast tissue ADC value did not improve the diagnostic accuracy rate. Positive and negative predictive values and diagnostic accuracy rates of ADC values and ratios increased as the lesion size increased. Key Words: Breast mass, Diffusion weighted imaging, ADC value, ADC ratio, Normalised ADC.