Inhibition of colony growth of primary explanted melanoma cells by KP46, cisplatin, and fotemustine, determined at various concentrations by the Human Tumor Cloning Assay in soft-agar medium. (a) Comparison of all ten KP46 [tris(8-quinolinolato)gallium(III)]-treated specimens; (b) comparison of KP46 and fotemustine, indicating thestronger cytostatic effect of the gallium complex; and (c) comparison of KP46 and cisplatin, indicating comparable activity. T/C, treated/control.