FOLH1 and brain cancer: A next study on RLT for patients with malignant brain tumours will first be directed at establishing the maximum tolerated dose and minimum treatment interval time (phase I), followed by preliminary efficacy (phase II) of ssIA-PSMA-based RLT, likely using lutetium-177, initially adjuvant to existing strategies, and subsequently combined with other strategies to optimise radioligand uptake at the tumour site.