Exogenous treatment with short course therapy of purified hSulf-2 insufficient for tumor xenograft inhibition. Athymic nude mice were randomized into two experimental groups (n = 16 each) and injected with MDA-MB-231 cells. On day 2 after injection, intratumoral injections were started with rhSulf2 or equivalent volume of vehicle. No significant difference was noted in average tumor xenograft volume after short course intratumoral injections of purified rhSulf2. Average volume as estimated by high resolution 3D ultrasound scanning of tumors at day 9 (A). Two methods for estimation of tumor size are shown in panels B-D. In the first method, width and height measurements (B) in combination with length (C) can be used in ellipsoid volume calculations as described above. Alternatively, tumor tracings in multiple frames (C) can be used to recreate a 3-dimensional tumor reconstruction and estimated volume (E). Given the irregular nature of these tumors, this second method was employed for capturing aberrancies from true ellipsoid shape. In this case, ultrasound-estimated volume is ~73 mm3 compared to an equation-calculated volume of ~85 mm3. This smaller volume is not surprising considering that caliper measurements include the overlying subcutaneous tissue whereas intra-ultrasound caliper measurements measure only the tumor itself.