Because the [125I]I-NpG-D-PSMA structure that contained D-form glutamic acids showed high tumor accumulation and rapid clearance from the kidney compared to [125I]I-NpG-L-PSMA, we developed a radiolabeled compound in which the 125I of [125I]I-NpG-D-PSMA was replaced with 211At. Here, FOLH1 is linked to neoplasm.