Perfusion Parameters in Dynamic Contrast-enhanced MRI and Apparent Diffusion Coefficient Value in Diffusion-weighted MRI: Association with Prognostic Factors in Breast Cancer

Rationale and Objectives: To evaluate the association of prognostic factors and subtypes of breast cancer with perfusion parameters in dynamic contrast-enhanced magnetic resonance imaging and apparent diffusion coefficient (ADC) values in diffusion weighted magnetic resonance imaging. Materials and Methods: Quantitative perfusion parameters (constant of transfer from plasma to interstitium, constant of transfer from the interstitium to the plasma, extravascular/extracellular volume per unit of volume of tissue [v(e)], and initial area under the concentration curve [(i)AUG]) and ADC values in the entire tumor volume of 52 invasive ductal carcinomas were obtained using histogram analysis. Four measures (25th percentile, mean, median, 75th percentile) were calculated for each parameter and the ADC value. Associations of perfusion parameters and ADC values with prognostic factors and tumor subtypes were analyzed. Results: Among perfusion parameters, (i)AUC(mean) and;(i)AUC(median) were greater in tumors larger than 2 cm (8.23 +/- 2.33, 8.64 +/- 2.67 x 10(4)) than in those smaller than 2 cm (6.99 +/- 1.92, 7.04 +/- 2.15 x 10(4); P = 0.046, 0.023). V-e (median) was higher in tumors with progesterone receptor (PR) positivity (0.54 +/- 0.18) than in those with PR negativity (0.44 +/- 0.1, P = 0.041). There were higher ADC(mean) and ADC(median) in tumors with human epidermal growth factor receptor 2 (HER2) positivity (1.306 and 1.278 x 10(-3) mm(2)/s) than in those with HER2 negativity (1.078 and 1.053 x 10(-3) mm(2)/s; P = 0.012 and 0.020). Higher ADC(mean) and ADC(median) were observed in HER2-enriched type (1.404 and 1.378 x 10(-3) mm(2)/s) than in luminal type (1.096 and 1.073 x 10(-3) mm(2)/s; P = 0.030 and 0.045). Conclusions: Among perfusion parameters, (i)AUC was associated with tumor size and v(e median) was associated with PR positivity. Mean and median ADC values showed positive correlation with HER2-positive and HER2-enriched tumors.