FOLH1 and prostate cancer: ICP-MS in combination with the non-radioactive derivatives, 175Lu-PSMA-617 and 159Tb-PSMA-617, enabled quantification of the accumulation of these compounds in target prostate cancer tissue and non-target tissue, including excretory organs.19 Indeed, side-by-side γ-counting (using radioactive analogues) and ICP-MS studies yielded near-identical data.