Pharmacokinetic evaluation and dosimetry analyses of 211At-CXCR4 mAb revealed that the TIs, tumor-to-bone marrow and tumor-to-kidney, for the tumor of 10 g, were 44.5 and 79.4, and the TIs for the tumor of 20 g were 22.3 and 39.7, respectively. This evidence concerns the gene CXCR4 and neoplasm.