Fig. 2:

[1-¹³C]pyruvate and [1-¹³C]lactate images acquired following intravenous injection of hyperpolarized [1-¹³C]pyruvate in a breast cancer patient. (A) Coronal image, where the tumor can be visualized as a region of hypointensity. (B) Dynamic contrast enhanced (DCE) image, where the tumor can be visualized as a region of hyperintensity. ¹³C magnetic resonance spectroscopic images of (C) hyperpolarized [1-¹³C]pyruvate and (D) hyperpolarized [1-¹³C]lactate; arrows indicate a region with low signal intensity corresponding to a region of low enhancement on the contrast agent-enhanced image. (E) Map of the ratio of lactate and pyruvate signal intensities, showing intratumoral heterogeneity; open arrow indicates an area of low [1-¹³C]pyruvate signal but high lactate labeling; closed arrow indicates a tumor area with high [1-¹³C]pyruvate signal and intermediate lactate labelling. (F-G) Dynamic hyperpolarized [1-¹³C]pyruvate and [1-¹³C]lactate images acquired after intravenous injection of hyperpolarized [1-¹³C]pyruvate (temporal resolution = 4 s). Reproduced from Gallagher, F.A. et al. [35], with permission (https://creativecommons.org/licenses/by-nc-nd/4.0/legalcode).