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Simple Summary: The purpose of this review was to provide an overview of all the available evidence regarding the use of fibroblast activation protein inhibitor (FAPI) as a tracer for positron emission tomography (PET) in patients with lung cancer. In several studies and case reports, radioisotope-labelled FAPI PET/CT showed a strong diagnostic performance in lung cancer. In addition, the possible prognostic value of FAPI PET/CT in lung cancer is proposed. Fibroblast activation protein (FAP) could be a promising target for tumor imaging and therapy, as it is expressed in >90% of epithelial cancers. A high level of FAP-expression might be associated with worse prognosis in several cancer types, including lung cancer. FAPI binds this protein and allows for labelling to Gallium-68, as well as several therapeutic radiopharmaceuticals. As FAP is only expressed at insignificant levels in adult normal tissue, FAPI provides a highly specific tumor-marker for many epithelial cancers. In this review, current information on the use of [68Ga]Ga-FAPI PET/CT in lung cancer is presented. [68Ga]Ga-FAPI shows a high uptake (standardized uptake value = SUVmax) and tumor-to-background ratio (TBR) in primary lung cancer lesions, as well as in metastatic lesions of other tumor types located in the lung and in lung cancer metastases located throughout the body. Where a comparison was made to [18F]FDG PET/CT, [68Ga]Ga-FAPI showed a similar or higher SUVmax and TBR. In brain and bone metastases, [68Ga]Ga-FAPI PET/CT outperformed [18F]FDG PET/CT. In addition to this strong diagnostic performance, a possible prognostic value of [68Ga]Ga-FAPI PET/CT in lung cancer is proposed. [ABSTRACT FROM AUTHOR]

Purpose: To evaluate whether quantitative [18F]FDG-PET/CT assessment, including radiomic analysis of [18F]FDG-positive thyroid nodules, improved the preoperative differentiation of indeterminate thyroid nodules of non-Hürthle cell and Hürthle cell cytology. Methods: Prospectively included patients with a Bethesda III or IV thyroid nodule underwent [18F]FDG-PET/CT imaging. Receiver operating characteristic (ROC) curve analysis was performed for standardised uptake values (SUV) and SUV-ratios, including assessment of SUV cut-offs at which a malignant/borderline neoplasm was reliably ruled out (≥ 95% sensitivity). [18F]FDG-positive scans were included in radiomic analysis. After segmentation at 50% of SUVpeak, 107 radiomic features were extracted from [18F]FDG-PET and low-dose CT images. Elastic net regression classifiers were trained in a 20-times repeated random split. Dimensionality reduction was incorporated into the splits. Predictive performance of radiomics was presented as mean area under the ROC curve (AUC) across the test sets. Results: Of 123 included patients, 84 (68%) index nodules were visually [18F]FDG-positive. The malignant/borderline rate was 27% (33/123). SUV-metrices showed AUCs ranging from 0.705 (95% CI, 0.601–0.810) to 0.729 (0.633–0.824), 0.708 (0.580–0.835) to 0.757 (0.650–0.864), and 0.533 (0.320–0.747) to 0.700 (0.502–0.898) in all (n = 123), non-Hürthle (n = 94), and Hürthle cell (n = 29) nodules, respectively. At SUVmax, SUVpeak, SUVmax-ratio, and SUVpeak-ratio cut-offs of 2.1 g/mL, 1.6 g/mL, 1.2, and 0.9, respectively, sensitivity of [18F]FDG-PET/CT was 95.8% (95% CI, 78.9–99.9%) in non-Hürthle cell nodules. In Hürthle cell nodules, cut-offs of 5.2 g/mL, 4.7 g/mL, 3.4, and 2.8, respectively, resulted in 100% sensitivity (95% CI, 66.4–100%). Radiomic analysis of 84 (68%) [18F]FDG-positive nodules showed a mean test set AUC of 0.445 (95% CI, 0.290–0.600) for the PET model. Conclusion: Quantitative [18F]FDG-PET/CT assessment ruled out malignancy in indeterminate thyroid nodules. Distinctive, higher SUV cut-offs should be applied in Hürthle cell nodules to optimize rule-out ability. Radiomic analysis did not contribute to the additional differentiation of [18F]FDG-positive nodules. Trial registration number: This trial is registered with ClinicalTrials.gov: NCT02208544 (5 August 2014), https://clinicaltrials.gov/ct2/show/NCT02208544. [ABSTRACT FROM AUTHOR]

Background: There is a lack of data on the effect of rituximab, cyclophosphamide, doxorubicin, vincristine, and prednisone (R-CHOP) therapy on brain glucose metabolism of diffuse large B-cell lymphoma (DLBCL) patients, as measured by 18F-fluoro-2-deoxy-D-glucose positron emission tomography (FDG-PET). Moreover, the prognostic value of brain glucose metabolism measurements is currently unknown. Purpose: To investigate the use of FDG-PET for measurement of brain glucose metabolism in R-CHOP-treated DLBCL patients, and to assess its prognostic value. Material and Methods: This retrospective study included DLBCL patients who underwent FDG-PET including the brain. FDG-PET metabolic volume products (MVPs) of the entire brain, cerebral cortex, basal ganglia, and cerebellum were measured, before and after R-CHOP therapy. Whole-body total lesion glycolysis (TLG) was also measured. Results: Thirty-eight patients were included, of whom 18 had an appropriate end-of-treatment FDG-PET scan. There were no significant differences (P > 0.199) between pre- and post-treatment brain glucose metabolism metrics. Low basal ganglia MVP was associated with a significantly worse progression-free survival (PFS) and overall survival (OS) (P = 0.020 and P = 0.032), and low cerebellar MVP was associated with a significantly worse OS (P = 0.034). There were non-significant very weak correlations between pretreatment brain glucose metabolism metrics and TLG. In the multivariate Cox regression, only the National Comprehensive Cancer Network International Prognostic Index (NCCN-IPI) remained an independent predictor of PFS (hazard ratio 3.787, P = 0.007) and OS (hazard ratio 2.903, P = 0.0345). Conclusion: Brain glucose metabolism was not affected by R-CHOP therapy. Low pretreatment brain glucose metabolism was associated with a worse outcome, but did not surpass the predictive value of the NCCN-IPI. [ABSTRACT FROM AUTHOR]

The article discusses a study to assess the diagnostic value of F-fluoro-2-deoxy-D-glucose positron emission tomography/computed tomography (FDG-PET/CT) for lymphoma grading using direct and timely histopathological correlation. The criteria included histologically proven lymphoma and availability of pretreatment FDG-PET/CT within one month before diagnostic biopsy. It suggests the accuracy of FDG-PET/CT in differentiating aggressive non-Hodgkin lymphoma from indolent non-Hodgkin lymphoma.

Background: Detection of bone marrow involvement using 18F-fluoro-2-deoxy-D-glucose positron emission tomography/computed tomography (FDG-PET/CT) has been proposed as a non-invasive alternative to standard blind bone marrow biopsy (BMB) of the posterior iliac crest in patients with newly diagnosed diffuse large B-cell lymphoma (DLBCL). However, studies that directly compare FDG-PET/CT results with histopathology are currently lacking.Purpose: To directly compare both visual and quantitative bone marrow FDG-PET/CT to BMB at the right posterior iliac crest in patients with newly diagnosed DLBCL.Material and Methods: A total of 40 patients with newly diagnosed DLBCL, who had undergone FDG-PET/CT before BMB of the right posterior iliac crest, were retrospectively included. FDG-PET/CT images were visually assessed for bone marrow involvement in the right posterior iliac crest. 3D partial volume corrected mean standardized uptake value (cSUVmean), maximum standardized uptake value (SUVmax), and peak standardized uptake value (SUVpeak) were measured in the right posterior iliac crest, using volume of interest analysis. BMB of the right posterior iliac crest was used as reference standard for bone marrow involvement.Results: Sensitivity and specificity of visual FDG-PET/CT analysis for the detection of bone marrow involvement in the right posterior iliac crest were 14.3% (95% confidence interval [CI], 0.5-53.4%) and 100% (95% CI, 87.6-100%), respectively. cSUVmean, SUVmax, and SUVpeak of BMB-negative patients (1.4 ± 0.49, 2.2 ± 0.69, and 1.7 ± 0.59, respectively) considerably overlapped with those of BMB-positive patients (1.8 ± 0.53, 2.7 ± 0.71, and 2.2 ± 0.61, respectively).Conclusion: In a local, head-to-head comparison with BMB, the diagnostic value of both visual and quantitative FDG-PET/CT for the detection of bone marrow involvement is low in patients with newly diagnosed DLBCL. [ABSTRACT FROM AUTHOR]

Purpose. To determine the additional value of bone marrow biopsy (BMB) in the standard staging work-up of patients with newly diagnosed diffuse large B-cell lymphoma (DLBCL), in terms of risk assessment and treatment planning. Material and methods. A total of 113 consecutive patients with newly diagnosed DLBCL who had undergone standard pretreatment evaluation, including serum lactate dehydrogenase measurement, Eastern Cooperative Oncology Group performance status assessment, computed tomography or 18F-fluoro-2-deoxy-D-glucose positron emission tomography/computed tomography, and BMB, were retrospectively included. National Comprehensive Cancer Network International Prognostic Index (NCCN-IPI) score and treatment strategy were determined in each patient, once without and once with taking into account BMB results. Numbers and percentages of BMB-induced changes on NCCN-IPI-based risk stratification (i.e. formation of low, low-intermediate, high-intermediate, and high risk groups) and choice of treatment were calculated, along with 95% confidence intervals (CIs). Results. BMB was positive in 18 of 113 patients (15.9%, 95% CI 10.2-23.9 %). BMB-induced changes on NCCI-IPI-based risk stratification occurred in 9 of 113 patients (8.0%, 95% CI 4.1-14.6%). Five patients were upstaged from low-intermediate to high-intermediate risk, and four patients were upstaged from high-intermediate to high risk. BMB findings changed treatment planning in none of the 113 patients (0.0%, 95% CI 0.0-4.0%). Conclusion. Although BMB results upstaged the NCCN-IPI-based risk stratification in a small number of cases, this did not have any therapeutic implications in our patient series. These findings support the omission of BMB from routine staging of newly diagnosed DLBCL in the current risk stratification and treatment era. [ABSTRACT FROM AUTHOR]

Bone-seeking radiopharmaceuticals and bisphosphonates may be indicated in patients with cancer with painful osseous metastases to palliate pain symptoms or to prevent skeletal-related events. Both pharmaceuticals may have an additive or even synergistic palliative effect. The combined use of bone-seeking radiopharmaceuticals and bisphosphonates is, however, controversial because of assumed competition between both phosphonate-compounds at the bone level. We report a case of hormone-refractory prostate cancer (HRPC) with multiple painful osseous metastases. The patient was treated with samarium-153-ethylenediaminetetramethylphosphonic acid (153Sm-EDTMP; Quadramet®, CIS bio International, Saclay, France) in combination with zoledronic acid (Zometa®, Novartis, Stein, Switzerland). He was treated for 6 months with 4 weekly intervals of zoledronic acid in combination with 3 monthly intervals of 153Sm-EDTMP. No negative interaction was found, toxicity was low, and efficacy high. He experienced a total relief of pain, a significant decrease of prostate-specific antigen (PSA) and, surprisingly, a significant decrease of tumor burden. [ABSTRACT FROM AUTHOR]