¹²⁴Iodine (¹²⁴I) with its 4.2 d half-life is particularly attractive forin vivodetection and quantification of longer-term biological and physiological processes; the long half-life of¹²⁴I is especially suited for prolonged timein vivostudies of high molecular weight compounds uptake. Numerous small molecules and larger compounds like proteins and antibodies have been successfully labeled with¹²⁴I. Advances in radionuclide production allow the effective availability of sufficient quantities of¹²⁴I on small biomedical cyclotrons for molecular imaging purposes. Radioiodination chemistry with¹²⁴I relies on well-established radioiodine labeling methods, which consists mainly in nucleophilic and electrophilic substitution reactions. The physical characteristics of¹²⁴I permit taking advantages of the higher PET image quality. The availability of new molecules that may be targeted with¹²⁴I represents one of the more interesting reasons for the attention in nuclear medicine. We aim to discuss all iodine radioisotopes application focusing on¹²⁴I, which seems to be the most promising for its half-life, radiation emissions, and stability, allowing several applications in oncological and nononcological fields.

Glioblastoma multiforme (GBM) is the most common primary malignant brain tumor in adults with a median survival time less than one year. To date, there are only a limited number of effective agents available for GBM therapy and this does not seem to add much survival advantage over the conventional approach based on surgery and radiotherapy. Therefore, the development of novel therapeutic approaches to GBM is essential and those based on radionuclide therapy could be of significant clinical impact. Experimental evidence has clearly demonstrated that cancer cells have a particularly high fractional content of copper inside the nucleus compared to normal cells. This behavior can be conveniently exploited both for diagnosis and for delivering therapeutic payloads (theranostic) of the radionuclide copper-64 into the nucleus of cancerous cells by intravenous administration of its simplest chemical form as dichloride salt [⁶⁴Cu]CuCl₂. To evaluate the potential theranostic role of [⁶⁴Cu]CuCl₂in GBM, the present work reports results from a preclinical study carried out in a xenografted GBM tumor mouse model. Biodistribution data of this new agent were collected using a small-animal PET tomograph. Subsequently, groups of tumor implanted nude mice were treated with [⁶⁴Cu]CuCl₂to simulate single- and multiple-dose therapy protocols, and results were analyzed to estimate therapeutic efficacy.

The purpose of the report was to evaluate the role of fluorine-18 fluoro-2-deoxy-D-glucose positron emission tomography/computed tomography (F-FDG PET/CT) in staging gastric cancer comparing it with contrast enhancement computed tomography (CECT).This retrospective study included 45 patients who underwent performed whole body CECT and F-FDG PET/CT before any treatment. We calculated CECT and F-FDG PET/CT sensitivity, specificity, accuracy, positive and negative predictive values (PPV and NPV) for gastric, lymphnode, and distant localizations; furthermore, we compared the 2 techniques by McNemar test. The role of F-FDG PET/CT semiquantitative parameters in relation to histotype, grading, and site of gastric lesions were evaluated by ANOVA test.Sensitivity, specificity, accuracy, PPV and NPV of CECT, and F-FDG PET/CT for gastric lesion were, respectively, 92.11%, 57.14%, 86.66%, 92.11%, 57.14% and 81.58%, 85.71%, 82.22%, 96.88%, 46.15%. No differences were identified between the 2 techniques about sensitivity and specificity. No statistical differences were observed between PET parameters and histotype, grading, and site of gastric lesion. The results of CECT and F-FDG PET/CT about lymphnode involvement were 70.83%, 61.90%, 66.66%, 68%, 65% and 58.33%, 95.24%, 75.55%, 93.33%, 66.67%. The results of CECT and F-FDG PET/CT about distant metastases were 80%, 62.86%, 66.66%, 38.10%, 91.67% and 60%, 88.57%, 82.22%, 60%, 88.57%. FDG PET/CT specificity was significantly higher both for lymphnode and distant metastases.The F-FDG PET/CT is a useful tool for the evaluation of gastric carcinoma to detect primary lesion, lymphnode, and distant metastases using 1 single image whole-body technique. Integration of CECT with F-FDG PET/CT permits a more valid staging in these patients.

We investigated the diagnostic performance of Somatostatin Receptor Positron Emission Tomography/Computed Tomography (SSR-PET/CT) for the detection of primary lesion and initial staging of pancreatic neuroendocrine tumors (pNETs). A comprehensive literature search up to January 2020 was performed selecting studies in presence of: sample size ≥10 patients; index test (i.e., 68Ga-DOTATOC or 68Ga-DOTANOC or 68Ga-DOTATATE PET/CT); and outcomes (i.e., detection rate (DR), true positive, true negative, false positive, and false-negative). The methodological quality was evaluated with QUADAS-2. Pooled DR and pooled sensitivity and specificity for the identification of the primary tumor were assessed by a patient-based and a lesion-based analysis. Thirty-eight studies were selected for the qualitative analysis, while 18 papers were included in the meta-analysis. The number of pNET patients ranged from 10 to 142, for a total of 1143 subjects. At patient-based analysis, the pooled sensitivity and specificity for the assessment of primary pNET were 79.6% (95% confidence interval (95%CI): 71–87%) and 95% (95%CI: 75–100%) with a heterogeneity of 59.6% and 51.5%, respectively. Pooled DR for the primary lesion was 81% (95%CI: 65–90%) and 92% (95%CI: 80–97%), respectively, at patient-based and lesion-based analysis. In conclusion, SSR-PET/CT has high DR and diagnostic performances for primary lesion and initial staging of pNETs.

Spondylodiscitis is a spine infection for which a diagnosis by a magnetic resonance imaging (MRI) is considered the most appropriate imaging technique. The aim of this study was to compare the role of an ¹⁸F-fluorodeoxyglucose positron emission tomography/computed tomography (¹⁸F-FDG PET/CT) and an MRI in this field. For 56 patients with suspected spondylodiscitis for whom MRI and ¹⁸F-FDG PET/CT were performed, we retrospectively analyzed the results. Cohen’s κ was applied to evaluate the agreement between the two techniques in all patients and in subgroups with a different number of spinal districts analyzed by the MRI. Sensitivity, specificity, and accuracy were also evaluated. The agreements of the ¹⁸F-FDG PET/CT and MRI in the evaluation of the entire population, whole-spine MRI, and two-districts MRI were moderate (κ = 0.456, κ = 0.432, and κ = 0.429, respectively). In patients for whom one-district MRI was performed, ¹⁸F-FDG PET/CT and MRI were both positive and completely concordant (κ = 1). We also separately evaluated patients with suspected spondylodiscitis caused by Mycobacterium tuberculosis for whom the MRI and ¹⁸F-FDG PET/CT were always concordant excepting in 2 of the 18 (11%) patients. Sensitivity, specificity, and accuracy of the MRI and ¹⁸F-FDG PET/CT were 100%, 60%, 97%, and 92%, 100%, and 94%, respectively. Our results confirmed the ¹⁸F-FDG PET/CT diagnostic value in the diagnosis of spondylodiscitis is comparable to that of MRI for the entire spine evaluation. This could be considered a complementary technique or a valid alternative to MRI.