Fig. 4

Representative image of 231Br brain metastases (a) and corresponding ¹⁴C-Paclitaxel accumulation (b) in metastases 8 h after intravenous administration of radiolabeled paclitaxel. Paclitaxel concentrations from 100 μm squares as shown in image A and B were determined (1 = 1 ng/g, 2 = 1 ng/g, 3 = 10.5 ng/g, 4 = 293 ng/g, 5 = 261 ng/g). (c) Analysis of ¹⁴C-Paclitaxel concentration in tumor regions (− 300 μm to 0) and normal brain regions (0 to 300 μm). Data are mean ± SEM; n = 15 for all data points