Contribution of (18)F-FDG PET in the diagnostic assessment of fever of unknown origin (FUO): a stratification-based meta-analysis.

PURPOSE: The aim of this study was to quantify the contribution of FDG PET to the diagnostic assessment of fever of unknown origin (FUO), taking into account the diagnostic limitations resulting from the composite nature of this entity. METHODS: The PubMed/MEDLINE database was searched from 2000 to September 2015. Original articles fulfilling the following criteria were included: (1) FUO as the initial diagnosis, (2) no immunosuppressed or nosocomial condition, (3) final diagnosis not based on PET, (4) a follow-up period specified, (5) adult population, and (6) availability of adapted data for calculation of odds ratios (ORs). ORs were computed for each study and then pooled using a random effects model. Stratification-based sensitivity analyses were finally performed using the following prespecified criteria: (a) study design, (b) PET device, (c) geographic area, and (d) follow-up period. RESULTS: A meta-analysis of the 14 included studies showed that normal PET findings led to an increase in the absolute final diagnostic rate of 36 % abnormal PET findings to an increase of 83 %, corresponding to a pooled OR of 8.94 (95 % CI 4.18 - 19.12, Z = 5.65; p < 0.00001). The design of the studies influenced the results (OR 2.92, 95 % CI 1.00 - 8.53 for prospective studies; OR 18,57, 95 % CI 7.57 - 45.59 for retrospective studies; p = 0.01), whereas devices (dedicated or hybrid), geographic area and follow-up period did not. CONCLUSION: Abnormal PET findings are associated with a substantially increased final diagnostic rate in FUO. Consequently, FDG PET could be considered for inclusion in the first-line diagnostic work-up of FUO. Further randomized prospective studies with standardized FDG PET procedures are warranted to confirm this first-line position.

Dose-Intense Cisplatin-Based Neoadjuvant Chemotherapy Increases Survival in Advanced Cervical Cancer: An Up-to-Date Meta-Analysis.

PURPOSE: We set out to demonstrate the benefit of using dose-intense cisplatin-based neoadjuvant chemotherapy in terms of overall survival and progression-free survival. METHODS: We searched through MEDLINE and Cochrane Library databases up to May 2021 to identify randomized clinical trials comparing the benefit of using cisplatin-based neoadjuvant chemotherapy followed by local treatment with local treatment alone for the treatment of locally advanced cervical cancer. The PRISMA statement was applied. RESULTS: Twenty-two randomized clinical trials were retrieved between 1991 and 2019, corresponding to 3632 women with FIGO stages IB2-IVA cervical cancer. More than 50% of the randomized clinical trials were assessed as having a low risk of bias. There was no benefit of neoadjuvant chemotherapy on overall survival, but there was significant heterogeneity across studies (I2 = 45%, p = 0.01). In contrast, dose-intense cisplatin at over 72.5 mg/m2/3 weeks was significantly associated with increased overall survival (RR = 0.87, p < 0.05) with no heterogeneity across the pooled studies (I2 = 36%, p = 0.11). The survival benefit was even greater when cisplatin was administered at a dose over 105 mg/m2/3 weeks (RR = 0.79, p < 0.05). CONCLUSION: Even though radiotherapy combined with weekly cisplatin-based chemotherapy remains standard of care for the treatment of locally advanced cervical cancer, our meta-analysis makes it possible to consider the use of dose-intense cisplatin-based neoadjuvant chemotherapy when local treatment is suboptimal and opens perspectives for designing new clinical trials in this setting. Neoadjuvant chemotherapy could be proposed when surgery is local treatment instead of standard chemoradiotherapy for the treatment of locally advanced cervical cancer.

Clinical validation of time reduction strategy in continuous step-and-shoot mode during SPECT acquisition.

BACKGROUND: The SwiftScan solution (General Electric Healthcare) combines a new low-energy high-resolution sensitivity collimator and a tomographic step-and-shoot continuous (SSC) mode acquisition. The purpose of this study is to determine whether SSC mode can be used in clinical practice with shorter examination times, while preserving image quality and ensuring accurate semi-quantification. Twenty bone scan and 10 lung scan studies were randomly selected over a period of 2 months. Three sets of image datasets were produced: step-and-shoot (SS) acquisition, simulated 25% count reduction using the Poisson resampling method (SimSS), and SimSS continuous acquisition (SimSSC), where SimSS was summed with counts acquired during detector head rotation. Visual assessment (5-point Likert scale, 2 readers) and semi-quantitative evaluation (50 focal uptake from 10 bone studies), assessed by SUVmean, coefficient of variation (COV), and contrast-to-noise ratio (CNR), were performed using t test and Bland-Altman analysis. RESULTS: Intra-reader agreement was substantial for reader 1 (k = 0.71) and for reader 2 (k = 0.61). Inter-reader agreement was substantial for SS set (k = 0.93) and moderate for SimSSC (k = 0.52). Bland-Altman analysis showed a good interchangeability of SS and SimSSC SUV values. The mean CNR between SS and SimSSC was not significantly different: 42.9 ± 43.7 [23.7-62.1] vs. 43.1 ± 46 [22.9-63.3] (p = 0.46), respectively. COV values, assessing noise level, did not deviate significantly between SS and SimSSC: 0.20 ± 0.08 [0.18-0.23] vs. 0.21 ± 0.08, [0.18-0.23] (p = 0.15), respectively, whereas a significant difference was demonstrated between SS and SimSS: 0.20 ± 0.08 [0.18-0.23] vs. 0.23 ± 0.09 [0.20-0.25] (p < 0.0001), respectively. CONCLUSIONS: SSC mode acquisition decreases examination time by approximately 25% in bone and lung SPECT/CT studies compared to SS mode (~ 2 min per single-bed SPECT), without compromising image quality and signal quantification. This SPECT sensitivity improvement also offers the prospect of more comfortable exams, with less motion artifacts, especially in painful or dyspneic patients.

FDG PET/CT in a Patient With Mantle Cell Lymphoma and COVID-19: Typical Findings.

A 52-year-old woman with no medical history was admitted on March 18, 2020, presenting since 3 days asthenia, abdominal pain, and dry cough but no fever. Adenomegalies, splenomegaly, leukocytosis, and elevated LDH suggested mature lymphoproliferation. Considering the current health context, an RT-PCR testing for COVID-19 (coronavirus disease 2019) was performed and found to be positive. Early chest CT showed no sign of pulmonary infection but multiple adenomegalies. An F-FDG PET/CT performed 5 days later to assess the extent of the hemopathy revealed the apparition of FDG-avid bilateral ground glass and subpleural curvilinear opacities suggesting COVID-19-associated pneumopathy.

18F-FDG Imaging of a Case of Disseminated Nocardiosis.

Nocardiosis is an uncommon infection caused by ubiquitous environmental aerobic gram-positive filamentous bacteria, present in soil and water. Skin and lungs are usually the main targets of localized infections. Rarely, disseminated forms can occur in immunocompromised individuals. A 63-year-old man with a history of late-onset asthma and nasal and sinus polyposis treated with oral low-dose corticosteroid regimen presented with fever, headache, myalgia, skin erythematous plaques, and pustules. Brain MRI revealed multiple abscesses and pachymeningitis. F-FDG PET/CT was performed to assess the extent of the infection. Cutaneous samples and sputum culture isolated Nocardia brasiliensis, confirming diagnosis of disseminated nocardiosis.

FDG-PET biomarkers associated with long-term benefit from first-line immunotherapy in patients with advanced non-small cell lung cancer.

OBJECTIVE: To determine FDG-PET biomarkers associated with long-term benefit (LTB) and survival in advanced non-small cell lung cancer (NSCLC) patients receiving first-line immunotherapy. METHODS: In this multicenter study, we retrospectively analyzed advanced NSCLC patients with a PD-L1 tumor proportion score (TPS) ≥ 50%, who underwent FDG-PET/CT before first-line pembrolizumab, received from August 2017 to September 2019. Parameters extracted were SUVmax, SUVmean, TMTV (total metabolic tumor volume) and TLG (total lesion glycolysis). LTB was defined as objective (complete or partial) response or stable disease as best overall response, maintained for ≥ 12 months. A multivariate prediction model was developed using logistic regression for LTB and Cox models for progression-free survival (PFS) and overall survival (OS). RESULTS: On the 63 eligible patients, with a median follow-up of 13.4 (range, 1.5-29.1) months, 17 (27%) had LTB. Median PFS and OS were 7.7 months (95%CI 5.0-10.5) and 12.1 months (95%CI 8.6-15.6). In multivariate analyses, high TMTV (> 84cm3) and high tumor SUVmean (> 10.1) remained independent factors for predicting LTB (OR 0.2; p = 0.03 and OR 3.7; p = 0.04) and PFS (HR 2.2; p = 0.02 and HR 0.5; p = 0.045). High TMTV was significantly associated with poor OS (HR 3.1; p = 0.03). No association was observed between tumor SUVmax or TLG and clinical outcomes. CONCLUSIONS: In patients with advanced NSCLC and PD-L1 TPS ≥ 50%, baseline low TMTV and high tumor SUVmean correlate with survival and LTB from upfront pembrolizumab. Beyond the initial staging, FDG-PET/CT scan could provide relevant biomarkers associated with clinical outcomes that should be taken into account when considering first-line treatment options.

Association of the Metabolic Score Using Baseline FDG-PET/CT and dNLR with Immunotherapy Outcomes in Advanced NSCLC Patients Treated with First-Line Pembrolizumab.

Background: We aimed to assess the clinical utility of a previously published score combining the total metabolic tumor volume (TMTV) on baseline FDG-PET/CT and pretreatment derived from the neutrophils to lymphocytes ratio (dNLR) for prognostication in NSCLC patients undergoing first-line immunotherapy (IT). Methods: In this multicenter retrospective study, 63 advanced NSCLC patients with a PD-L1 tumor proportion score (TPS) ≥50%, who underwent FDG-PET/CT before first-line IT, treated from January 2017 to September 2019, were enrolled. Associations between this score and the progression-free survival (PFS), overall survival (OS), disease control rate (DCR), and overall response rate (ORR) were evaluated. Results: The median (m) PFS and mOS were 7.7 (95% CI 4.9-10.6) and 12.1 (8.6-15.6) months, respectively, and DCR and ORR were 65% and 58%, respectively. mOS was 17.9 months (14.6 not reached) for the good group versus 13.8 (95%CI 8.4-18.9) and 6.6 (CI 2.0-11.2) months for the intermediate and poor groups, respectively. mPFS was 15.1 (95%CI 12.1-20.0) months for the good group versus 5.2 (1.9-8.5) and 1.9 (95%CI 1.3-2.5) months for the intermediate and poor groups, respectively. The poor prognosis group was associated with DCR and ORR (p < 0.05). Conclusions: The metabolic score combining TMTV on the baseline FDG-PET/CT scan and pretreatment dNLR was associated with the survival and response in a cohort of advanced NSCLC patients with ≥50% PD-L1 receiving frontline IT.