FOLH1 and breast cancer: Even though theranostic applications in nuclear medicine with radionuclides like gallium-68 and lutetium-177 were booming in the past decade, due to the striking development of [68Ga]Ga-PSMA-11 which led to the introduction of several other PSMA-targeting radiolabelled ligands for diagnosis and therapy of PC, new compounds targeting BC are rare and mostly intended for improving diagnosis.