Copper-64 labeled nanoparticles for positron emission tomography imaging: a review of the recent literature.

INTRODUCTION: Nuclear medicine plays a crucial role for personalized therapy, mainly in oncology. Chemotherapy and radiotherapy present some disadvantages and research is shifting toward nanotechnology with significant improvements in therapy and diagnosis of several cancers. Indeed, nanoparticles can be tagged with different radioisotopes for single photon emission computed tomography (SPECT) and positron emission tomography (PET) imaging and for therapy. This review describes the current state of the art of 64Copper-labeled nanoparticles for PET imaging of cancer. EVIDENCE ACQUISITION: We performed a systematic analysis of literature using the terms "64CuCl2," "64Cu," "Copper" AND "nanoparticle" AND "PET" in online databases: i.e. PubMed/MEDLINE and Scopus. The search was limited to English papers and original articles. We excluded articles not in English language, abstracts, case reports, review articles and meeting presentations. EVIDENCE SYNTHESIS: Amongst the 116 articles retrieved, 88 were excluded because reviews, or not in English, or only in-vitro studies or meeting presentations. We considered only 28 original papers. The most used nanoparticles are liposomes and they are mainly used in breast cancer although other animal models of cancer have been also investigated. CONCLUSIONS: The results showed that nanoparticles can be considered a promising radiopharmaceutical for PET imaging of different type of cancer.

[18F]FDG PET/CT in Patients Affected by SARS-CoV-2 and Lymphoproliferative Disorders and Treated with Tocilizumab.

OBJECTIVES: Interstitial pneumonia is a severe complication induced by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. Several treatments have been proposed alone or, more often, in combination, depending, also, on the presence of other organ disfunction. The most frequently related, well-described, and associated phenomenon is pan-lymphopenia with circulating, high levels of cytokines. We report, here, on two patients with COVID-19 and lymphoproliferative disorders treated with Tocilizumab (a humanized monoclonal antibody against the interleukin-6 receptor) and followed by an [18F]FDG PET/CT to early evaluate the therapy's efficacy. METHODS: One patient with angioimmunoblastic T-lymphoma (A), one with Hodgkin lymphoma (A), and both with positive RT-PCR for SARS-CoV-2 and with similar clinical findings of interstitial pneumonia at the CT scan, were imaged by [18F]FDG PET/CT before and 14 days after a single dose of Tocilizumab. RESULTS: In both patients, the basal [18F]FDG PET/CT showed a diffused lung parenchyma uptake, corresponding to the hyperdense areas at the CT scan. After 2 weeks of a Tocilizumab infusion, patient B had an improvement of symptoms, with normalization of the [18F]FDG uptake. By contrast, patient A, who was still symptomatic, showed a persisting and abnormal distribution of [18F]FDG. Interestingly, both patients showed a low bone marrow uptake of [18F]FDG at the diagnosis and after 15 days, while the spleen uptake was low only in lymphopenic patient A; both are indirect signs of an immune deficiency. CONCLUSIONS: In conclusion, in these two patients, interstitial pneumonia was efficiently treated with Tocilizumab, as demonstrated by the [18F]FDG PET/CT. Our results confirm that interleukin-6 (IL6) has a role in the COVID-19 disease and that anti-cytokine treatment can also be performed in patients with lymphoproliferative disorders.