First Extensive Analysis of 18F-Labeled Fluorodeoxyglucose Positron Emission Tomography-Computed Tomography in a Large Cohort of Patients With HIV-Associated Hodgkin Lymphoma: Baseline Total Metabolic Tumor Volume Affects Prognosis.

PURPOSE: 18F-labeled fluorodeoxyglucose positron emission tomography with computed tomography (18F-FDG PET-CT) data in HIV-associated Hodgkin lymphoma (HIV-HL) are scarcely reported. In addition to the description of the characteristics of both baseline and interim 18F-FDG PET-CT examinations (PET1 and iPET, respectively), the aim of this study was to assess the prognostic value of PET1 and previously identified clinical parameters in this population. PATIENTS AND METHODS: PET1 of 109 patients with HIV-HL, treated with doxorubicin, bleomycin, vinblastine, and dacarbazine chemotherapy regimen since 2007, and 104 iPET were centrally reviewed. All the patients were enrolled in an ongoing prospective single-center cohort of HIV-associated lymphoma. RESULTS: Most patients had a disseminated disease according to the Ann Arbor classification (30% stage III and 43% stage IV), with especially bone marrow and liver as extranodal localizations. After a median follow-up of 6.7 years, 12 patients relapsed (11%) and 13 died (12%). Five-year progression-free survival (PFS) was 75.1%, and 5-year overall survival was 86.1%. Median total metabolic tumor volume (TMTV) was 121.4 cm3. The optimal TMTV cutoff identified for prognostic analysis was 527 cm3, with a 2-year PFS of 71% in the 20 patients with TMTV > 527 cm3, compared with 91% in the 89 patients with TMTV ≤ 527 cm3 (P = .004). On multivariate analysis, a high TMTV was the only parameter independently associated with PFS. CONCLUSION: In this large series of HIV-HL patients with a homogeneous management, high TMTV on PET1 examination was associated with a poor prognosis.

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.

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.

Comparison Between ESC and Duke Criteria for the Diagnosis of Prosthetic Valve Infective Endocarditis.

OBJECTIVES: The primary objective was to assess the value of the European Society of Cardiology (ESC) criteria, including 18F-fluorodeoxyglucose positron emission tomography/computed tomography (18F-FDG-PET/CT) in prosthetic valve infective endocarditis (PVE). Secondary objectives were: 1) to assess the reproducibility of 18F-FDG-PET/CT; 2) to compare its diagnostic value with that of echocardiography; and 3) to assess the diagnostic value of the presence of a diffuse splenic uptake BACKGROUND: 18F-FDG PET/CT has been added as a major criterion in the ESC 2015 infective endocarditis (IE) guidelines, but the benefit of the ESC criteria has not been prospectively compared with the conventional Duke criteria. METHODS: Between 2014 and 2017, 175 patients with suspected PVE were prospectively included in 3 French centers. After exclusion of patients with uninterpretable 18F-FDG PET/CT, 115 patients were evaluated, including 91 definite and 24 rejected IE, as defined by an expert consensus. RESULTS: Cardiac uptake by 18F-FDG PET/CT was observed in 67 of 91 patients with definite PVE and 6 with rejected IE (sensitivity 73.6% [95% confidence interval (CI): 63.3% to 82.3%], specificity 75% [95% CI: 53.3% to 90.2%]). The ESC 2015 classification increased the sensitivity of Duke criteria from 57.1% (95% CI: 46.3% to 67.5%) to 83.5% (95% CI: 74.3% to 90.5%) (p < 0.001), but decreased its specificity from 95.8% (95% CI: 78.9% to 99.9%) to 70.8% (95% CI: 48.9% to 87.4%). Intraobserver reproducibility of 18F-FDG PET/CT was good (kappa = 0.84) but interobserver reproducibility was less satisfactory (kappa = 0.63). A diffuse splenic uptake was observed in 24 (20.3%) patients, including 23 (25.3%) of definite PVE, and only 1 (4.2%) rejected PVE (p = 0.024). CONCLUSIONS: 18F-FDG PET/CT is a useful diagnostic tool in suspected PVE, and explains the greater sensitivity of ESC criteria than Duke criteria. However, 18F-FDG PET/CT also presents with important limitations concerning its feasibility, specificity, and reproducibility. Our study describes for the first time a new endocarditis criterion, that is, the presence of a diffuse splenic uptake on 18F-FDG PET/CT.

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.

Prognostic value of one millisievert exercise myocardial perfusion imaging in patients without known coronary artery disease.

The aim of this study was to assess the prognostic value of normal ultra-low-dose exercise MPI with a CZT camera. METHODS: 1901 consecutive patients without known CAD referred for exercise MPI with 1.8 MBq/kg (0.05 mCi) of Tc99m sestamibi or tetrofosmin and a CZT camera were included prospectively. Patients with an abnormal scan requiring an additional resting image (230) or a submaximal exercise test (271) were excluded. The 1400 remaining patients were followed for 39 months. The primary end-point was cardiac events (cardiac death, nonfatal myocardial infarction, and revascularization). The secondary end-point was noncardiac death. RESULTS: The mean injected activity was 145 ± 37 MBq (3.9 ± 1 mCi), the mean acquisition duration was 10 ± 0.7 minutes, and the mean effective dose was 0.91 ± 0.13 mSv. 1288 patients (92%) achieved full follow-up. We observed 22 cardiac events and 16 noncardiac deaths. The annualized rates were equivalent to 0.55% for cardiac events and 0.37% for noncardiac mortality. CONCLUSIONS: Normal ultra-low-dose exercise MPI with a CZT camera has a high negative predictive value. The effective dose was less than 1 mSv, and the study thus allays concerns about radiation burden.

The Use of FDG PET-CT Imaging for the Assessment of Early Antifungal Treatment Response in Disseminated Fusariosis.

Fusariosis is an opportunistic infection, caused by a filamentous fungus, found on plants and in soil. The treatment of disseminated pattern, seen in immunocompromised patients with severe neutropenia, is difficult because of antifungal therapy resistance. A 12-year-old girl, who was diagnosed with B-cell acute lymphoblastic leukemia, developed multiple widespread skin papules and subcutaneous nodules, at day 20 of consolidation therapy. Histological examination with cultures of skin tissue revealed Fusarium species. Treatment was started with intravenous liposomal amphotericin B and voriconazole. To assess treatment response, FDG PET/CT performed at baseline, at 2 and 4 months, showed a partial response.

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.

First experience DaTSCAN imaging using cadmium-zinc-telluride gamma camera SPECT.

We report our first experience of brain DaTSCAN SPECT imaging using cadmium-zinc-telluride gamma camera (CZT-GC) in 2 cases: a 64-year-old patient suffering from essential tremor and a 73-year-old patient presenting with atypical bilateral extrapyramidal syndrome. In both cases, 2 different acquisitions were performed and compared, using a double-head Anger-GC, followed immediately by a second acquisition on CZT-GC. There were no significant visual differences between images generated by different GC. Our first result suggests that DaTSCAN SPECT is feasible on CZT-GC, allowing both injected dose and acquisition time reductions without compromising image quality. This experience needs to be evaluated in larger series.

Low-dose thallium-201 protocol with a cadmium-zinc-telluride cardiac camera.

OBJECTIVES: Thallium-201 is efficient for myocardial perfusion imaging, but leads to relatively high radiation exposure in patients. The purpose of this study was to compare the efficiency of low-dose thallium-201 imaging with cadmium-zinc-telluride (CZT) cameras with regular-dose thallium-201 imaging with conventional cameras. METHODS: We prospectively studied 137 consecutive patients referred for stress myocardial perfusion imaging who had previously had a myocardial single-photon emission computed tomography with thallium-201. We injected at stress a low dose of thallium-201 (1.1 MBq/kg, 28 µCi/kg), performed a 5-7 min scan with a CZT camera (GE DNM 530c), and assessed redistribution imaging when the initial images were abnormal. We compared the CZT scan with the conventional dual-head tomographic camera scan taken previously with a regular dose of thallium-201. RESULTS: The average delay between both scans was 22 months. The stress dose was 88 ± 16 (2.38 ± 0.43 mCi) versus 125 ± 13 MBq (3.38 ± 0.34 mCi; a 30% reduction). The time for camera acquisition was 6 versus 13 min (a 54% reduction). The myocardial counts were increased two-fold with CZT (mean: 446 Kcounts). The quality of CZT images was better in 69% of the cases. There were 59 artifacts with conventional cameras and 29 artifacts with CZT (P<0.01). The diagnostic agreement was calculated in patients without clinical or angiographic changes between both scans (115 patients) and was high (97%). The effective dose at stress was less than 12 mSv. High myocardial counting allowed for further decrease in the injected activity, leading to an effective dose as low as 8 mSv. CONCLUSION: With reduced activities of thallium-201 and low effective doses, the CZT camera provides reliable, high-quality imaging.

Brain SPECT thallium using cadmium zinc telluride: a first experience.

A 70-year-old man underwent a thallium-201 brain SPECT in the work-up and characterization of a frontotemporal mass. SPECT images were performed on cadmium zinc telluride system during only 5 minutes and after the injection of only 2 mCi. Images demonstrated high thallium uptake in frontotemporal areas considered as a potential malignant tumor. Surgical removal confirmed the diagnosis of malignant glioblastoma. The thallium SPECT fast acquisition imaging on cadmium zinc telluride systems is feasible with reduced injected dose. This method allows a significantly decrease of patient radiation exposure without compromising the image quality. This initial experience needs to be confirmed and optimized in larger clinical studies.

Comparison of myocardial perfusion imaging using thallium-201 between a new cadmium-zinc-telluride cardiac camera and a conventional SPECT camera.

PURPOSE OF THE REPORT: Cadmium zinc telluride (CZT) solid-state detectors have been recently introduced in myocardial perfusion imaging. However, they had not been yet validated with thallium-201. This study compares the clinical performances of the CZT ultrafast camera GE DNM 530c with a conventional SPECT camera (CC) using thallium-201. MATERIALS AND METHODS: We prospectively studied with thallium-201 a total of 153 consecutive patients referred for myocardial perfusion imaging at exercise (3-4 mCi) then redistribution (with 1 mCi reinjection). Sequential acquisitions were performed first with a conventional dual-head tomographic Anger camera (CC) in 10 to 15 minutes and then with a CZT camera (CZT) in 5 minutes, in prone position. RESULTS: In all, 9 patients were excluded: 1 for mispositioning, 3 for camera failure, 3 for delayed acquisition after exercise, 1 for nonacceptance of redistribution, 1 for motion. Acquisition was more comfortable with CZT for all patients. Global counts rate was higher with CZT than with CC (3.6±0.57 KCts/s vs. 1.14±0.16). CZT has a 5-fold increased myocardial counts rate compared with CC (448±69 Kcts in 5 minutes vs. 209±40 Kcts in 12.5±1.8 minutes). Quality of CZT images was considered as better in 40%, equal in 56%, and worse in 4% of cases; we found less artifacts with CZT; diagnostic conclusions were the same in 140 of 144 cases (97%); discordances were 2 artifacts with CC and 2 small ischemia (less than 2 segments) missed by CZT. CONCLUSIONS: This new dedicated cardiac CZT camera allows with thallium-201 five minutes acquisitions with an increased image quality and a reliable diagnosis quality.

Fatal heart failure after a 26-month combination of tyrosine kinase inhibitors in a papillary thyroid cancer.

BACKGROUND: Patients with progressive refractory thyroid cancer are potential candidates for clinical trials using tyrosine kinase inhibitors (TKIs), and a promising proportion of patients in these trials have achieved stable disease. Here we report an unusual adverse experience in a patient receiving a combination of TKIs. SUMMARY: The patient was a 62-year-old man with chronic myloid leukemia (CML) and thyroid carcinoma that did not concentrate iodide and had metastases. He was started on imatinib for his CML. About 5 months later he was started on sorafenib for his thyroid cancer. At this time he had no risk factors for cardiac disease except moderate obesity. He had a complete cytogenetic response in his CML, and a partial response in his thyroid cancer. Twenty-one months after starting the combination of TKIs, he manifested signs of coronary artery disease. He received a combination of medications and his TKIs were continued. He died of a sudden myocardial infarction with cardiogenic shock 28 months after starting the combination of TKIs. A retrospective analysis of sequential 18-fludeoxyglucose positron emission tomography scans (18-FDG PET scans) were indicative of cardiac toxicity developing during the period of concomitant administration of TKIs. CONCLUSION: We report the first case of apparent lethal cardiotoxicity with imatinib-sorafenib combined therapy. Combination TKI treatment may enhance the risk of adverse effects. Our experience with this patient suggests that cardiac PET scan should be monitored closely in these type of patients.

Comparison between PET and PET/CT in recurrent head and neck cancer and clinical implications.

The aim of this retrospective study was to compare the diagnostic accuracy between positron emission tomography (PET) and combined PET/computed tomography (PET/CT) in the detection of recurrent head and neck squamous cell carcinoma (HNSCC) and to evaluate the degree of interobserver agreement. Thirty-two patients who had undergone curative treatment for HNSCC and who presented with a suspicion of recurrent local disease were studied with fluoro-2-deoxy-D-glucose (FDG)-PET imaging. All patients had undergone an inconclusive conventional workup (nasofibroscopy, CT scan and/or MRI). PET and PET/CT were reviewed by two nuclear medicine physicians independently. Performances of PET and PET/CT were compared using biopsy and/or clinical follow-up of at least 8 months as gold-standard. ROC curves were employed for statistical analysis. Out of 32 patients, 18 (56%) had a local recurrence. Intraclass correlation coefficients were strong (>90) and statistically significant (P < 0.0001) for the two reviewers in all cases. The sensitivity, specificity and accuracy of PET were found to be 94%, between 36 and 50% and between 69 and 75%, respectively, depending on the consideration of equivocal cases. Results for PET/CT were found to be 94, 57 and 78%. The utility scores of PET and PET/CT were 0.72 and 0.78, respectively. PET/CT could have a direct impact on patient care with the avoidance of 8/14 (57%) unnecessary invasive procedures (panendoscopy under general anaesthesia). Combined PET/CT is more accurate than PET alone for detection of recurrent HNSCC. The findings of this study are reinforced by the strong interobserver agreement in the interpretation of the results.

99mTc-ECD brain perfusion SPECT in hyperalgesic fibromyalgia.

PURPOSE: Neuro-imaging studies with (99m)Tc-HMPAO SPECT in fibromyalgia (FM) patients have reported only limited subcortical hypoperfusion. (99m)Tc-ECD SPECT is known to provide better evaluation of areas of high cerebral blood flow and regional metabolic rate. We evaluated a homogeneous group of hyperalgesic patients with FM using (99m)Tc-ECD SPECT. The aim of this study was to investigate brain processing associated with spontaneous pain in FM patients. METHODS: Eighteen hyperalgesic FM women (mean age 49 years, range 25-63 years; American College of Rheumatology criteria) and ten healthy women matched for age were enrolled in the study. A voxel-by-voxel group analysis was performed using SPM2 (p<0.05, corrected for multiple comparisons). Visual Analogue Scale score for pain was 82+/-4 at the time of the SPECT study. RESULTS: Compared with control subjects, we observed individual brain SPECT abnormalities in FM patients, confirmed by SPM2 analysis, with hyperperfusion of the somatosensory cortex and hypoperfusion of the frontal, cingulate, medial temporal and cerebellar cortices. CONCLUSION: In the present study, performed without noxious stimuli in hyperalgesic FM patients, we found significant hyperperfusion in regions of the brain known to be involved in the sensory dimension of pain processing and significant hypoperfusion in areas assumed to be associated with the affective-attentional dimension. As current pharmacological and non-pharmacological therapies act differently on the two components of pain, we hypothesise that SPECT could be a valuable and readily available tool to guide individual therapeutic strategy and provide objective follow-up of pain processing recovery under treatment.

[Role of [18F]-FDG PET-CT in the management of the head and neck cancers]. / Intérêt de la TEP-TDM au [(18)F]-FDG dans la prise en charge des cancers des voies aérodigestives supérieures.

OBJECTIVES: To evaluate the impact of [(18)F]-FDG PET/CT image fusion in the management of carcinomas of the upper aero-digestive tract. METHODS: This retrospective study included 169 patients with squamous cell cacinoma of the upper aerodigestive tract who underwent a PET/CT for : initial staging (n = 47), cervical lymphadenopathy from an unknown primary (n = 22), post treatment surveillance (n = 68) and detection of recurrent cancer (n = 32). Results of PET/CT were compared with those of standard workup (CT scan of head, neck and chest and abdominal ultrasound). Histology and clinical follow-up were used as gold-standard. RESULTS: PET/CT was more accurate than standard workup for 6.4 % of patients for the initial staging, 18,2 % of patients for cervical lymphadenopathy from an unknown primary, 20,6 % of patients for post-treatment surveillance and 25 % of patients for detection of cancer recurrence. In all patients, 17,9 % of FDG uptake foci found by PET/CT were false-positives. CONCLUSION: PET/CT is a reliable tool for the management of carcinomas of the upper aerodigestive tract. The high rate of false-positive findings represents the main limitation of this exam.