Ventilation/perfusion SPECT/CT findings in different lung lesions associated with COVID-19: a case series.

PURPOSE: The aim of this series of cases is to show the aspects of ventilation/perfusion single-photon emission computed tomography combined with computed tomography (V/Q SPECT/CT) in patients hospitalized for COVID-19 pneumonia, with the worsening of respiratory symptoms raising the suspicion of a pulmonary embolism. Patients did not benefit from CT angiography for various reasons: a contraindication, unavailability of the CT angiography, or a low clinical probability for pulmonary embolism. METHODS: We retrospectively describe the results of the V/Q SPECT/CT of five patients hospitalized for COVID-19 pneumonia in the nuclear medicine departments of the Centre Cardiologique du Nord and of the Delafontaine hospital in Saint-Denis (Ile-de-France, France) between April 2, 2020, and April 10, 2020. These patients had persistent dyspnea or chest pain suggesting pulmonary embolism. RESULTS: The V/Q SPECT/CT allowed to diagnose a pulmonary embolism in one of these five patients. We also noted several characteristics of the perfusion and ventilation depending on the lung lesions on the CT scan. The areas affected by COVID-19 were most often responsible for ventilatory anomalies with a relatively preserved perfusion. In more advanced cases of pneumonia, with alveolar fillings, the perfusion was also reduced or absent in accordance with large ventilation defects. In addition, the healthy parenchyma appeared to benefit from an uptake in ventilation and perfusion. CONCLUSION: V/Q SPECT/CT can play a role in the management of patients hospitalized for COVID-19 for the diagnosis of embolic complications with meticulous hygienic precautions. The different characteristics of the ventilatory and perfusion anomalies related to COVID-19 pneumonia will be confirmed with the next cases. In addition, in this pandemic context and facing a significant infectious risk, the utility of ventilation will also have to be specified.

Good clinical practice recommendations for the use of PET/CT in oncology.

Positron emission tomography/computed tomography (PET/CT) is a nuclear medicine functional imaging technique with proven clinical value in oncology. PET/CT indications are continually evolving with fresh advances made through research. French practice on the use of PET in oncology was framed in recommendations based on Standards-Options-Recommendations methodology and coordinated by the French federation of Comprehensive Cancer Centres (FNLCC). The recommendations were originally issued in 2002 followed by an update in 2003, but since then, a huge number of scientific papers have been published and new tracers have been licenced for market release. The aim of this work is to bring the 2003 version recommendations up to date. For this purpose, a focus group was set up in collaboration with the French Society for Nuclear Medicine (SFMN) to work on developing good clinical practice recommendations. These good clinical practice recommendations have been awarded joint French National Heath Authority (HAS) and French Cancer Institute (INCa) label status-the stamp of methodological approval. The present document is the outcome of comprehensive literature review and rigorous appraisal by a panel of experts, organ specialists, clinical oncologists, surgeons and imaging specialists. These data were also used for the EANM referral guidelines.

Feasibility of simultaneous dual isotope acquisition for myocardial perfusion imaging with a cadmium zinc telluride camera.

BACKGROUND: We studied the impact of technetium-99m (99mTc) in the thallium-201 (201Tl) energy window (70 keV) to determine if CZT cardiac cameras allow us to perform simultaneous dual-isotope acquisition for myocardial perfusion imaging. METHODS: We included 117 consecutive patients. We injected 0.7 MBq/kg of 201Tl at stress, performed the first scan (image T1), then injected at rest 2 MBq/kg of 99mTc-tetrofosmin and immediately acquired a second scan with reconstruction in the energy window of thallium (image T2). A corrected thallium image was created by the subtraction of 99mTc downscattered photons (image TS). We compared spectra, image quality, and semiquantitative scores on T1, T2, and TS images. RESULTS: Though T2 images were of worse quality, TS images were of equal quality compared to T1 images in most cases. Scores show an underestimation of abnormalities in 20% of patients on T2 images and in 10% on TS images. CONCLUSIONS: Despite the improved energy resolution of CZT cameras, downscatter of technetium in the 201Tl window leads to an underestimation of the pathological territory in 10% to 20% of cases. It does not allow us to use simultaneous dual-isotope acquisition in clinical practice without additional tools for scatter correction.

Integrated analysis of 18F-FDG PET/CT improves preoperative lymph node staging for patients with invasive bladder cancer.

OBJECTIVES: Preoperative 18F-fluoro-2-deoxy-D-glucose (18F-FDG) positron emission tomography/computed tomography (PET/CT) is controversial to assess lymph node (LN) staging in patients with invasive bladder cancer. We proposed to use the maximum standardized uptake value (SUVmax) associated with axial-based LN size to improve the detection of regional LN metastasis. METHODS: From May 2015 to May 2017, we prospectively included patients with urothelial bladder cancer who underwent radical cystectomy with extended pelvic LN dissection. All patients underwent preoperative 18F-FDG PET/CT staging before surgery. The gold standard comparator was the pathological examination of resected LNs. The data were reported on a regional per area- and patient-based model according to SUVmax values and axial-based LN size criteria. RESULTS: In total, 1012 LNs were identified in 61 patients with clinically localized invasive bladder cancer who underwent radical cystectomy and extended pelvic LN dissection. Loco-regional involvement of 24 LN areas was confirmed in 17 patients. In per area analysis, diagnostic accuracy of PET/CT and CT alone were respectively 84% and 78% (p = 0.039). On patient-based analysis, combined PET/CT correctly classified pelvic LN status in 5/61 (+ 8%) additional patients using optimal thresholds compared to CT alone, with accuracies of 82% and 74%, respectively (p = 0.13). CONCLUSION: Combining SUVmax and axial-based LN size criteria using 18F-FDG PET/CT improved the diagnostic accuracy for preoperative LN staging in patients with invasive bladder cancer, in per area analysis. KEY POINTS: • Combining metabolical and morphological features using18F-FDG PET/CT improves the detection of malignant lymph node in patients with bladder cancer. • 18 F-FDG PET/CT may help for initial staging of patients with muscle invasive bladder cancer.

Performance of FDG PET/CT at initial diagnosis in a rare lymphoma: nodular lymphocyte-predominant Hodgkin lymphoma.

PURPOSE: Nodular lymphocyte-predominant Hodgkin lymphoma (NLPHL) is a rare Hodgkin lymphoma distinguished from classical Hodgkin lymphoma (cHL) by the nature of the neoplastic cells which express B-cell markers. We wanted to determine the diagnostic performance of FDG PET/CT in initial assessment and its therapeutic impact on staging. METHODS: We retrospectively studied a population of 35 patients with NLPHL (8 previously treated for NLHPL, 27 untreated). All patients underwent an initial staging by pretherapeutic FDG PET/CT. The impact on initial stage or relapse stage was assessed by an independent physician. RESULTS: In a per-patient analysis, the sensitivity of the pretherapeutic FDG PET/CT was 100%. In a per-site analysis, the sensitivity, specificity, positive predictive value, negative predictive value and accuracy of pretherapeutic FDG PET/CT were 100%, 99%, 97%, 100% and 99%, respectively. Pretherapeutic FDG PET/CT led to a change in the initial stage/relapse stage in 12 of the 35 patients (34%). In contrast to previous results established without FDG PET/CT, 20% of patient had osteomedullary lesions. CONCLUSION: Pretherapeutic FDG PET/CT has excellent performance for initial staging or relapse staging of NLPHL.

Images of COVID-19 Infection Cases in Asymptomatic or Paucisymptomatic Patients With Neoplastic Diseases on 18F-FDG PET/CT.

We describe the results of F-FDG PET/CT of 3 patients referred to our institution during the single day of Monday, March 23, 2020, for an initial assessment of cancer extension or for the therapeutic evaluation of chemotherapy of neoplastic pathology, with no obvious infectious or respiratory symptoms at the time of examination. A retrospective review of the recent clinical history of patients in association with the typical pulmonary images on CT scan suggested the diagnosis of COVID-19. The characteristic aspects of COVID-19 infection should be recognized on F-FDG PET/CT, even if patients are asymptomatic or minimally symptomatic.

The Role of 18F-FDG PET/CT in Guiding Precision Medicine for Invasive Bladder Carcinoma.

Bladder cancer (BC) is the 10th most common cancer worldwide. Approximately one quarter of patients with BC have muscle-invasive disease (MIBC). Muscle-invasive disease carries a poor prognosis and choosing the optimal treatment option is critical to improve patients' outcomes. Ongoing research supports the role of 2-deoxy-2-(18F)fluoro-D-glucose positron emission tomography (18F-FDG PET) in guiding patient-specific management decisions throughout the course of MIBC. As an imaging modality, 18F-FDG PET is acquired simultaneously with either computed tomography (CT) or MRI to offer a hybrid approach combining anatomical and metabolic information that complement each other. At initial staging, 18F-FDG PET/CT enhances the detection of extravesical disease, particularly in patients classified as oligometastatic by conventional imaging. 18F-FDG PET/CT has value in monitoring response to neoadjuvant and systemic chemotherapy, as well as in localizing relapse after treatment. In the new era of immunotherapy, 18F-FDG PET/CT may also be useful to monitor treatment efficacy as well as to detect immune-related adverse events. With the advent of artificial intelligence techniques such as radiomics and deep learning, these hybrid medical images can be mined for quantitative data, providing incremental value over current standard-of-care clinical and biological data. This approach has the potential to produce a major paradigm shift toward data-driven precision medicine with the ultimate goal of personalized medicine. In this review, we highlight current literature reporting the role of 18F-FDG PET in supporting personalized management decisions for patients with MIBC. Specific topics reviewed include the incremental value of 18F-FDG PET in prognostication, pre-operative planning, response assessment, prediction of recurrence, and diagnosing drug toxicity.

[Update of the recommendations of good clinical practice for the use of PET in oncology]. / Actualisation des recommandations de bonne pratique clinique pour l'utilisation de la TEP en cancérologie.

Positron Emission Tomography (PET) is a functional nuclear medicine imaging technique which clinical value in oncology has been demonstrated. PET indications are constantly evolving, thanks to the contribution of research. The use of PET in oncology has been the subject of recommendations according to the Standard-Options-Recommendations methodology from the Fédération Nationale des Centres de Lutte Contre le Cancer in 2002, updated in 2003. However, many scientific works have been published since 2003 and new tracers have also obtained a marketing authorization in France. The objective of this work was therefore to update the recommendations established in 2003. In this context, in collaboration with the Société française de médecine nucléaire, a working group was set up for the development of good clinical practice recommendations under the HAS-INCA methodological label. The present document is issued from a comprehensive review of the literature and rigorous appraisal by a panel of national experts, organ specialists, clinical oncologists, surgeons, and imaging specialists. It is intended to be used as a guide to decision-making for those oncology teams that are able to manage patients in various situations in which the AMM label is not sufficiently precise.

Secondary Hyperparathyroidism With "Superscan-Like" Hypermetabolic FDG PET/CT Pattern.

A 26-year-old man with chronic terminal renal insufficiency under dialysis was referred in our institution for a checkup before kidney transplantation to ensure the absence of malignant neoplasm. The patient had a biological secondary hyperparathyroidism with highly elevated serum parathormon, and treatment with parathyroid surgery was planned before the kidney transplant. Whole-body FDG PET/CT showed no apparent malignant neoplasm, but increased metabolism of the 4 parathyroid gland and the other pitfalls of advanced secondary hyperparathyroidism on chronic renal insufficiency: pseudotumoral calcification in soft tissues, diffuse hypermetabolic bone dystrophy, and osteolytic lesion of pelvic and peripheral skeleton corresponding to brown tumors.