GRPR and breast cancer: Moreover, a phase I dose escalation study with the compound [212Pb]Pb-DOTAM-GRPR1 is currently ongoing in patients with recurrent or metastatic GRPR-expressing tumors, including BC patients, and will contribute to elucidate such concerns by determining the single and multiple ascending doses of this novel GRPR-targeting radiopharmaceutical (NCT05283330) (105).