MC1R and neoplasm: The [68Ga]Ga-CCZ01048 tracer exhibited high binding affinity to MC1R with sub-nanomolar Ki values, rapid internalization into B16F10 melanoma cells, high in vivo stability in blood plasma, and exceptional PET image contrast in vivo with tumour-to-blood, tumour-to-muscle, tumour-to-bone and tumour-to-kidney ratios of 96.4 ± 13.9, 210.9 ± 20.9, 39.6 ± 11.9 and 4.0 ± 0.9, respectively, at 2 h post-injection (Zhang et al. 2017).