PET imaging in breast cancer

The application of Positron Emission Tomography (PET) using 2-[F18] fluoro-2-deoxy- D-Glucose (FDG) and the more recently fused technique of Computerized Tomography and PET (PET/CT) in patients with breast cancer is reviewed. Their role in diagnosis of primary tumour, staging, chemotherapy monitoring and radiotherapy planning, follow-up and restaging is introduced. The advantages of combination of anatomical and functional images are emphasized and the comparison with other imaging techniques is highlighted

The Role of Nuclear Medicine in Imaging and Therapy of Neuroendocrine Tumors

Neuroendocrine tumors (NET’s) constitute a heterogeneous group of tumors characterized by the simultaneous expression of specific marker proteins and cell type-specific hormonal products. Metaiodobenzyluanidine (MIBG), labelled with 131I or 123I, and 111In-pentetreotide (Octreoscan) are the radiopharmaceuticals of choice in the current clinical practice. Positron emitting radiopharmaceuticals that are used in PET imaging are 18F-fluorodeoxyglucose (18F-FDG), 18F-fluorodopamine (18F-DOPA), 11C-hydroxy-tryptophan (11C-HTP), and Gallium-68 (68Ga-DOTATATE or DOTATOC).  In diagnosis of gastroenteropancreatic neuroendocrine tumors (GEPs) Octreoscan is the preferred imaging method because of its high sensitivity. 131Ι/123Ι-MIBG scintigraphy is useful to characterize and locate intra-adrenal (pheochromocytomas) and extra-adrenal paragangliomas. Octreoscan has also high accuracy for extra-adrenal paragangliomas. 18F-FDG-PET or PET/CT seems to be useful in detecting the pheochromocytomas and GEPs that fail to concentrate MIBG and Octreocan. 123I-MIBG scintigraphy combined with urine analysis of catecholamine metabolites is the most sensitive indicator of neuroblastoma. In diagnosis of small cell lung cancer and pituitary adenomas Octreoscan has a high sensitivity. On the contrary, in medullary thyroid cancer the sensitivity of Octreoscan and 131Ι/123Ι-MIBG is low but sensitivity of 18F-FDG PET or PET/CT and 68Ga-DOTATATE and DOTATOC PET or PET/CT seems to be higher.  With the introduction of 131I-MIBG and octreotide labelled with several radioisotopes, the field of treatment with radionuclides has been extended to a wide range of NETs. 111In-DTPA-Octreotide firstly was used in some clinical trials but recent advances in somatostatin analogues have paved the way to the development of octreotate, which can be labelled with both 177Lu and 90Y radionuclides

Impact of COVID-19 on cardiovascular testing in the United States versus the rest of the world

Objectives: This study sought to quantify and compare the decline in volumes of cardiovascular procedures between the United States and non-US institutions during the early phase of the coronavirus disease-2019 (COVID-19) pandemic. Background: The COVID-19 pandemic has disrupted the care of many non-COVID-19 illnesses. Reductions in diagnostic cardiovascular testing around the world have led to concerns over the implications of reduced testing for cardiovascular disease (CVD) morbidity and mortality. Methods: Data were submitted to the INCAPS-COVID (International Atomic Energy Agency Non-Invasive Cardiology Protocols Study of COVID-19), a multinational registry comprising 909 institutions in 108 countries (including 155 facilities in 40 U.S. states), assessing the impact of the COVID-19 pandemic on volumes of diagnostic cardiovascular procedures. Data were obtained for April 2020 and compared with volumes of baseline procedures from March 2019. We compared laboratory characteristics, practices, and procedure volumes between U.S. and non-U.S. facilities and between U.S. geographic regions and identified factors associated with volume reduction in the United States. Results: Reductions in the volumes of procedures in the United States were similar to those in non-U.S. facilities (68% vs. 63%, respectively; p = 0.237), although U.S. facilities reported greater reductions in invasive coronary angiography (69% vs. 53%, respectively; p < 0.001). Significantly more U.S. facilities reported increased use of telehealth and patient screening measures than non-U.S. facilities, such as temperature checks, symptom screenings, and COVID-19 testing. Reductions in volumes of procedures differed between U.S. regions, with larger declines observed in the Northeast (76%) and Midwest (74%) than in the South (62%) and West (44%). Prevalence of COVID-19, staff redeployments, outpatient centers, and urban centers were associated with greater reductions in volume in U.S. facilities in a multivariable analysis. Conclusions: We observed marked reductions in U.S. cardiovascular testing in the early phase of the pandemic and significant variability between U.S. regions. The association between reductions of volumes and COVID-19 prevalence in the United States highlighted the need for proactive efforts to maintain access to cardiovascular testing in areas most affected by outbreaks of COVID-19 infection

Role of Positron Emission Tomography in the Early Prediction of Response to Chemotherapy in Patients With Non-Small-Cell Lung Cancer

In recent years, molecular imaging with [F-18]fluorodeoxyglucose-positron-emission tomography, [F-18]FDG-PET, has become part of the standard of care in initial staging of patients with non-small-cell lung cancer. Currently, there is an increasing interest in the role of [F-18]FDG-PET in the evaluation of biological characteristics of the tumor and the prediction of response to anticancer therapies at an early phase of treatment. According to the existing data, quantitative assessment of therapy-induced changes in tumor [F-18]FDG uptake may allow the prediction of tumor response and patient outcome very early in the course of therapy. Treatment may be adjusted according to the chemosensitivity of the tumor tissue in an individual patient. Thus, [F-18]FDG-PET has the potential to reduce the side effects and costs of ineffective therapy. This review provides an update on recent studies that evaluate the role of [F-18]FDG-PET in the early prediction of response to chemotherapy and prognosis in patients with non-small-cell lung cancer. In addition, it discusses the application of [F-18]FDG-PET to the monitoring of new targeted forms of anticancer therapy and particularly of epidermal growth factor receptor tyrosine kinase inhibitors. Finally, it evaluates the usefulness of [F-18]fluorothymidine, a PET tracer for imaging tumor proliferation, in predicting response to therapy in patients with lung cancer

Does CEA and CA 19-9 combined increase the likelihood of F-18-FDG in detecting recurrence in colorectal patients with negative CeCT?

Aim The purpose of this prospective study was to investigate the role of 2-(fluorine-18)-fluoro-2-deoxy-d-glucose (F-18-FDG) PET/computed tomography (CT) in the diagnosis of recurrent colorectal cancer (CRC) in patients with increased tumor markers and negative contrast-enhanced computed tomography (CeCT) results. Material and methods Forty-three patients (27 male; median age 66 years, range 31-93 years) with increasing tumor markers and negative CeCT during follow-up for treated CRC underwent F-18-FDG PET/CT examinations. The serum values of carcinoembryonic antigen (CEA) (n=29) and CA 19-9 (n=20) were normal after completion of treatment, with subsequent increasing concentrations. Results Among the 43 patients, F-18-FDG PET/CT was true positive in 32 (74.4%), false positive in two (4.7%), false negative in one (2.3%), and true negative in eight (1%) patients. On the patient-basis analysis, F-18-FDG PET/CT had a sensitivity of 97% (confidence interval: 0.82-0.99), a specificity of 80% (0.44-0.96), a positive predictive value of 94% (0.78-0.98), and a negative predictive value of 88% (0.5-0.99). There was no statistically significant correlation between CRC recurrence and CEA and CA19-9 levels (P=0.561 and 0.55, respectively). Only in the group of patients (n=6) with both tumor markers increased did F-18-FDG PET/CT have 100% accuracy in revealing recurrent disease. Conclusion F-18-FDG PET/CT is highly sensitive in the diagnosis of recurrent CRC in patients with increasing levels of tumor markers and negative CeCT regardless of the type or level of tumor marker; however, the combination of elevated CEA and CA 19-9 increases the likelihood of F-18-FDG in detecting recurrence

Preparation and Evaluation of ⁶⁴Cu-Radiolabled Dual-Ligand Multifunctional Gold Nanoparticles for Tumor Theragnosis

Gold nanoparticles (AuNPs) are cutting-edge platforms for combined diagnostic and therapeutic approaches due to their exquisite physicochemical and optical properties. Using the AuNPs physically produced by femtosecond pulsed laser ablation of bulk Au in deionized water, with a capping agent-free surface, the conjugation of functional ligands onto the AuNPs can be tunable between 0% and 100% coverage. By taking advantage of this property, AuNPs functionalized by two different types of active targeting ligands with predetermined ratios were fabricated. The quantitatively controllable conjugation to construct a mixed monolayer of multiple biological molecules at a certain ratio onto the surface of AuNPs was achieved and a chelator-free 64Cu-labeling method was developed. We report here the manufacture, radiosynthesis and bioevaluation of three different types of dual-ligand AuNPs functionalized with two distinct ligands selected from glucose, arginine–glycine–aspartate (RGD) peptide, and methotrexate (MTX) for tumor theragnosis. The preclinical evaluation demonstrated that tumor uptakes and retention of two components AuNP conjugates were higher than that of single-component AuNP conjugates. Notably, the glucose/MT- modified dual-ligand AuNP conjugates showed significant improvement in tumor uptake and retention. The novel nanoconjugates prepared in this study make it possible to integrate several modalities with a single AuNP for multimodality imaging and therapy, combining the power of chemo-, thermal- and radiation therapies together

International Impact of COVID-19 on the Diagnosis of Heart Disease

Background: The coronavirus disease 2019 (COVID-19) pandemic has adversely affected diagnosis and treatment of noncommunicable diseases. Its effects on delivery of diagnostic care for cardiovascular disease, which remains the leading cause of death worldwide, have not been quantified. Objectives: The study sought to assess COVID-19's impact on global cardiovascular diagnostic procedural volumes and safety practices. Methods: The International Atomic Energy Agency conducted a worldwide survey assessing alterations in cardiovascular procedure volumes and safety practices resulting from COVID-19. Noninvasive and invasive cardiac testing volumes were obtained from participating sites for March and April 2020 and compared with those from March 2019. Availability of personal protective equipment and pandemic-related testing practice changes were ascertained. Results: Surveys were submitted from 909 inpatient and outpatient centers performing cardiac diagnostic procedures, in 108 countries. Procedure volumes decreased 42% from March 2019 to March 2020, and 64% from March 2019 to April 2020. Transthoracic echocardiography decreased by 59%, transesophageal echocardiography 76%, and stress tests 78%, which varied between stress modalities. Coronary angiography (invasive or computed tomography) decreased 55% (p &lt; 0.001 for each procedure). In multivariable regression, significantly greater reduction in procedures occurred for centers in countries with lower gross domestic product. Location in a low-income and lower–middle-income country was associated with an additional 22% reduction in cardiac procedures and less availability of personal protective equipment and telehealth. Conclusions: COVID-19 was associated with a significant and abrupt reduction in cardiovascular diagnostic testing across the globe, especially affecting the world's economically challenged. Further study of cardiovascular outcomes and COVID-19–related changes in care delivery is warranted

Reduction of cardiac imaging tests during the COVID-19 pandemic: The case of Italy. Findings from the IAEA Non-invasive Cardiology Protocol Survey on COVID-19 (INCAPS COVID)

Background: In early 2020, COVID-19 massively hit Italy, earlier and harder than any other European country. This caused a series of strict containment measures, aimed at blocking the spread of the pandemic. Healthcare delivery was also affected when resources were diverted towards care of COVID-19 patients, including intensive care wards. Aim of the study: The aim is assessing the impact of COVID-19 on cardiac imaging in Italy, compare to the Rest of Europe (RoE) and the World (RoW). Methods: A global survey was conducted in May–June 2020 worldwide, through a questionnaire distributed online. The survey covered three periods: March and April 2020, and March 2019. Data from 52 Italian centres, a subset of the 909 participating centres from 108 countries, were analyzed. Results: In Italy, volumes decreased by 67% in March 2020, compared to March 2019, as opposed to a significantly lower decrease (p &lt; 0.001) in RoE and RoW (41% and 40%, respectively). A further decrease from March 2020 to April 2020 summed up to 76% for the North, 77% for the Centre and 86% for the South. When compared to the RoE and RoW, this further decrease from March 2020 to April 2020 in Italy was significantly less (p = 0.005), most likely reflecting the earlier effects of the containment measures in Italy, taken earlier than anywhere else in the West. Conclusions: The COVID-19 pandemic massively hit Italy and caused a disruption of healthcare services, including cardiac imaging studies. This raises concern about the medium- and long-term consequences for the high number of patients who were denied timely diagnoses and the subsequent lifesaving therapies and procedures