Identically to the observations experienced in the case of the subcutaneously growing primary Ne/De tumours, the SUV values of the subrenally located tumours notably decreased (p ≤ 0.01) after the injection of the unlabelled compound (T/M SUVmean blocked: 1.71 ± 0.24 vs. unblocked: approx. 9 and T/M SUVmax blocked: 1.96 ± 0.56 vs. unblocked: 12.47 ± 2.19) that authenticates the APN/CD13 adhering capacity of the tracer. This evidence concerns the gene ANPEP and neoplasm.