Quantificationally, Figure 5D showed a significant positive correlation between tumor S-[18F]CF3-D-CYS uptake values (represented by mean TNRs) and the corresponding Ki67 labeling index (n = 14, R2 = 0.72, P < 0.01), indicating that tumor S-[18F]CF3-D-CYS uptake values could reflect the proliferative ability of tumor cells. This evidence concerns the gene MKI67 and neoplasm.