The enhanced PSMA affinity, 111/natIn-CC34 and 111/natIn-PSMA-617 resulted in two- to five-fold increased internalization rate and higher but also longer tumor retention compared to 64/natCu- and 68/natGa-CC34 and 68/natGa-HBED-CC-PSMA. This evidence concerns the gene CXCR1 and neoplasm.