It showed a moderate tumor uptake of 2.1 ± 0.39% ID/g, but high T/B ratio of 9.4 at 1 h p. i. Specific binding of 99mTc-AMD3465 to CXCR4 was demonstrated by treatment with excess unlabeled AMD3465 which reduced tumor uptake by 36%. Here, CXCR4 is linked to neoplasm.