Radionuclide-based nanotechnologies in brain tumors: an updated overview

Purpose: Nanotechnology has revolutionized the field of diagnostics and therapy in oncology, particularly for brain tumors and metastases. Radiolabelled nanoparticles, due to their ability to cross the blood-brain barrier and selectively accumulate in tumor tissues, emerge as key tools for both diagnosis and treatment. We studied their integration with SPECT and PET, which has improved imaging sensitivity and specificity. Their application in nanotheranostics opens new perspectives for more effective diagnostic and therapeutic strategies. Methods: A systematic literature review was conducted using PubMed, Scopus and Embase databases (last update November 2024), with keywords related to brain tumors, nanoparticles, radiopharmaceuticals, PET, SPECT, and therapy. Relevant studies on the application of radiolabelled nanotechnologies for both diagnosis and treatment of primary and metastatic brain tumors were selected. Results: In diagnostics, liposomes, mesoporous silica nanoparticles, and gold nanostructures radiolabelled with isotopes such as Zirconium-89, Gallium-68, and Iodine-124 have demonstrated high multimodal imaging capabilities with PET and SPECT. On the therapeutic side, radiolabelled nanoparticles with Rhenium-188, Yttrium-90, and Lutetium-177 have shown effective intra-tumoral retention and potential targeted therapeutic effects, reducing systemic toxicity compared to conventional treatments. Conclusions: Radiolabelled nanoparticles represent a significant advancement in the management of brain tumors, combining advanced diagnostics and targeted therapy in a theranostic approach. While preclinical results are promising, challenges remain regarding long-term safety, large-scale production, and regulatory approval for clinical application.