Imaging lymph node metastasis on a 4T1 breast cancer model. A) Bioluminescence image of two BALB/c mice was taken 10 d after hock inoculation. B) SPECT/CT images taken at 24 h post IV injection of 111In-S-LCP. Two horizontal and two vertical sections were shown. The enlarged and tumor loaded sentinel, popliteal lymph node could be directly compared with the counter-side, popliteal lymph node. C) GFP fluorescent images of the metastatic 4T1-luc2-GFP cancer cells in the lymph nodes. Eight lymph nodes (from top to bottom: 2 axillary, 2 brachial, 2 inguinal, and 2 popliteal) from both side of one mouse were shown. D) S-LCP biodistribution 28 h post injection at liver, spleen, 4T1 tumor, and various lymph nodes by gamma counting. (N=3)