Histogram analysis of quantitative pharmacokinetic parameters on DCE-MRI: correlations with prognostic factors and molecular subtypes in breast cancer

BackgroundBreast cancer heterogeneity influences poor prognoses thorough therapy resistance. This study quantitatively evaluated intratumoral heterogeneity through a histogram analysis of dynamic contrast-enhanced MRI (DCE-MRI) pharmacokinetic parameters, and determined correlations with prognostic factors and molecular subtypes.MethodsWe retrospectively investigated 101 invasive ductal breast cancers from 99 women who underwent preoperative DCE-MRI between July 2012 and November 2014. Pharmacokinetic parameters (K-trans, k(ep), and v(e)) were obtained by the Tofts model. For each parameter, the mean, standard deviation, coefficient of variation, skewness, and kurtosis values of tumor were calculated, and prognostic factors and subtypes associations were assessed.ResultsThe mean of v(e) was lower in cancers with high Ki-67 than in cancers with low Ki-67 (P=0.002). The coefficient of variation of v(e) was higher in cancers with estrogen receptor negativity than in cancers with estrogen receptor positivity (P<0.001). The coefficient of variation of v(e) was also higher in cancers with high Ki-67 than in cancers with low Ki-67 (P<0.001). The skewness of v(e) was higher in cancers with high nuclear grade than in cancers with low nuclear grade (P=0.006). Triple-negative cancers showed higher v(e) coefficient of variation than did those with luminal A (P<0.001) and B (P=0.006).ConclusionsVarious v(e) parameters correlated with breast cancer prognostic factors and molecular subtypes.