FIGURE 4. Whole-body images of ^99mTc-methylene diphosphonate (A) and ¹⁷⁷Lu-J591 mAb (B) in patient with metastatic prostate cancer. ¹⁷⁷Lu images obtained on day 7 show significant localization of radiolabeled J591 mAb in most lesions identified on bone scan (A).