The relationship of intracellular sodium fraction and pharmacokinetics in breast cancer

Abstract

Motivation: Breast cancer MRI has high sensitivity but has an unmet need for increased specificity. Sodium MRI has the potential to improve tumor characterisation and thus treatments. Goal(s): To determine whether there is a relationship between tissue permeability by correlating intracellular sodium fraction with pharmacokinetic parameters. Approach: Conventional DCE-MRI parameters were acquired as well as intracellular sodium fraction maps (= inversion recovery sodium / total sodium concentration) in 17 breast cancer lesions (grade 1:n=3; grade 2: n=9; grade 3:n=7). Results: The fraction of intracellular sodium to total sodium concentration had significant correlations (p-values <0.11) with Ktrans and kep, and with cancer grade. Impact: Breast cancer imaging has an unmet need to differentiate ductal carcinoma from benign and invasive lesions. Sodium MRI can provide intra- and extra-cellular sodium measurements, which may improve lesion differentiation by using endogenous contrast.