Though IC50 and lipophilicity data of carbamate I (3) were comparable to [177Lu]Lu-PSMA-10 ([177Lu]Lu-1), internalization was distinctly lower (67.8 ± 0.5% for [177Lu]Lu-3 vs. 177 ± 15% for [177Lu]Lu-1), which might explain decreased tumor accumulation at 1 h and 24 h p.i. However, low internalization may not be the only reason for decreased tumor uptake. Here, PDZD4 is linked to neoplasm.