FDG uptake reflects an immune-enriched subtype of thyroid cancer: Clinical implications of imaging-based molecular characterization.

INTRODUCTION: Iodine and FDG uptakes have been established as methods to define the biological properties of thyroid cancer. As various cells in the tumor microenvironment (TME) affect tumor metabolism, we investigated the association between glucose metabolism in thyroid cancer and the TME using transcriptomic analyses. METHODS: We used F-18 FDG PET and RNA sequencing data of thyroid cancer to find associations between TME cell types and glucose metabolism. In addition, publicly available single-cell RNA sequencing data of papillary thyroid cancer was used to investigate glucose metabolism in cell types of the TME. The correlations between the FDG uptake and biological properties of the TME, including glucose metabolism and tumor differentiation score (TDS) were evaluated. Estimation of the proportions of immune and cancer cells (EPIC) was performed. The biological properties of each cell type were also assessed in the single-cell RNA sequencing data. RESULTS: FDG uptake showed a positive correlation with the enrichment score of macrophages and glycolysis activity. In single-cell RNA sequencing, immune cells had both high glucose transporters (GLUTs) and glycolysis signatures, while thyrocytes including cancer cells showed relatively low GLUTs and glycolysis signatures, suggesting that FDG uptake mainly occurred in immune cells of the TME. Moreover, the high GLUTs of myeloid cells were negatively associated with TDS. CONCLUSIONS: Our findings suggest that thyroid cancer with high FDG uptake can be mediated by enriched immune cells of the TME. We suggest that FDG uptake in thyroid cancer could be a marker for the immune-rich type and provide clinical implications for treatment stratification.

The Usefulness of Maximum Standardized Uptake Value at the Delayed Phase of Tc-99m sestamibi single-photon emission computed tomography/computed tomography for Identification of Parathyroid Adenoma and Hyperplasia.

Tc-99m sestamibi single-photon emission computed tomography/computed tomography (SPECT/CT) has been used to help surgeons explore the location of parathyroid diseases, but quantitative parameters have not been systemically investigated for this purpose. We aimed to establish objective criteria for adenoma and hyperplasia using the standardized uptake value (SUV) in patients with hyperparathyroidism.Thirty-nine hyperparathyroid patients (male/female: 17/22, age: 58.33 ±â€Š11.69 years) with at least 1 uptake-positive lesion of any degree by visual assessment in preoperative Tc-99m sestamibi quantitative SPECT/CT were included from Oct 2015 to Oct 2017. Pathologically, 44 lesions (32 adenomas and 12 hyperplasia) were identified. All patients experienced normalized levels of intact parathyroid hormone immediately after surgery. Quantitative SPECT/CT was performed at 10 minute and 2 hour post injection of Tc-99m sestabmibi (dose = 740 MBq), and maximum SUV (SUVmax) was measured for the parathyroid lesions. Experienced pathologists evaluated the percentage cellular proportions of chief cells, oxyphil cells, and clear cells.SUVmax (g/mL) of adenomas, hyperplasia, and reference thyroid tissue were 12.92 ±â€Š6.68, 7.90 ±â€Š5.49, and 7.01 ±â€Š2.62 at 10min (early phase), decreasing to 7.46 ±â€Š5.66, 4.65 ±â€Š3.14, and 2.21 ±â€Š1.07 at 2 hour (delayed phase), respectively. The adenomas showed significantly higher SUVmax than both the hyperplasia (P = .0131) and reference thyroid tissue (P < .0001) along the early and delayed phases, but the SUVmax of the hyperplasia did not differ from that of the reference thyroid tissue (P = .4196). The adenomas and hyperplasia were discriminated from the reference thyroid tissue using a cutoff SUVmax of 3.26 at the delayed phase. The adenomas had lower %proportions of oxyphil cells than the hyperplasia (P = .0054), but its SUVmax at the delayed phase was positively correlated with the %proportions of mitochondria-abundant oxyphil cells (rho = 0.418, P = .0173). The hyperplasia showed no correlation between SUVmax and cellular proportions.SUVmax at the delayed phase in the Tc-99m sestamibi quantitative SPECT/CT was useful for the identification and differentiation of parathyroid lesions causing hyperparathyroidism.

Pittsburgh B Compound Positron Emission Tomography in Patients With AL Cardiac Amyloidosis.

BACKGROUND: It remains unknown whether the noninvasive evaluation of the degree of amyloid deposition in the myocardium can predict the prognosis of patients with light chain (AL) cardiac amyloidosis. OBJECTIVES: The purpose of this study was to demonstrate that 11C-Pittsburgh B compound positron emission tomography (11C-PiB PET) is useful for prognostication of AL cardiac amyloidosis by noninvasively imaging the myocardial AL amyloid deposition. METHODS: This study consecutively enrolled 41 chemotherapy-naïve AL cardiac amyloidosis patients. The amyloid deposit was quantitatively assessed with amyloid P immunohistochemistry in endomyocardial biopsy specimens and was compared with the degree of myocardial 11C-PiB uptake on PET. The primary endpoint was a composite of all-cause death, heart transplantation, and acute decompensated heart failure. RESULTS: The degree of myocardial 11C-PiB PET uptake was significantly higher in the cardiac amyloidosis patients compared with normal subjects and correlated well with the degree of amyloid deposit on histology (R2 = 0.343, p < 0.001). During follow-up (median: 423 days, interquartile range: 93 to 1,222 days), 24 patients experienced the primary endpoint. When the cardiac amyloidosis patients were divided into tertiles by the degree of myocardial 11C-PiB PET uptake, patients with the highest PiB uptake experienced the worst clinical event-free survival (log-rank p = 0.014). The degree of myocardial PiB PET uptake was a significant predictor of clinical outcome on multivariate Cox regression analysis (adjusted hazard ratio: 1.185; 95% confidence interval: 1.054 to 1.332; p = 0.005). CONCLUSIONS: These proof-of-concept results show that noninvasive evaluation of myocardial amyloid load by 11C-PiB PET reflects the degree of amyloid deposit and is an independent predictor of clinical outcome in AL cardiac amyloidosis patients.

Comparative Analysis of Lung Perfusion Scan and SPECT/CT for the Evaluation of Functional Lung Capacity.

PURPOSE: This study aimed to compare lung perfusion scan with single photon emission computed tomography/computed tomography (SPECT/CT) for the evaluation of lung function and to elucidate the most appropriate modality for the prediction of postoperative lung function in patients with lung cancer. METHODS: A total of 181 patients underwent Tc-99m macroaggregated albumin lung perfusion scan and SPECT/CT to examine the ratio of diseased lung and diseased lobe. Forty-one patients with lung cancer underwent both preoperative and postoperative pulmonary function tests within 1 month to predict postoperative pulmonary function. Predicted postoperative forced expiratory volume in 1 s (ppoFEV1) was calculated by the % radioactivity of lung perfusion scan and SPECT, and the % volume of the residual lung, assessed on CT. RESULTS: The ratios of diseased lung as seen on lung perfusion scan and SPECT showed significant correlation, but neither modality correlated with CT. The ratios of the diseased lung and diseased lobe based on CT were higher than the ratios based on either perfusion scan or SPECT, because CT overestimated the function of the diseased area. The lobar ratio of both upper lobes was lower based on the perfusion scan than on SPECT but was higher for both lower lobes. Actual postoperative FEV1 showed significant correlation with ppoFEV1 based on lung perfusion SPECT and perfusion scan. CONCLUSIONS: We suggest SPECT/CT as the primary modality of choice for the assessment of the ratio of diseased lung area. Both perfusion scan and SPECT/CT can be used for the prediction of postoperative lung function.

Amyloid PET Quantification Via End-to-End Training of a Deep Learning.

PURPOSE: Although quantification of amyloid positron emission tomography (PET) is important for evaluating patients with cognitive impairment, its routine clinical use is hampered by complicated preprocessing steps and required MRI. Here, we suggested a one-step quantification based on deep learning using native-space amyloid PET images of different radiotracers acquired from multiple centers. METHODS: Amyloid PET data of the Alzheimer Disease Neuroimaging Initiative (ADNI) were used for this study. A training/validation consists of 850 florbetapir PET images. Three hundred sixty-six florbetapir and 89 florbetaben PET images were used as test sets to evaluate the model. Native-space amyloid PET images were used as inputs, and the outputs were standardized uptake value ratios (SUVRs) calculated by the conventional MR-based method. RESULTS: The mean absolute errors (MAEs) of the composite SUVR were 0.040, 0.060, and 0.050 of training/validation and test sets for florbetapir PET and a test set for florbetaben PET, respectively. The agreement of amyloid positivity measured by Cohen's kappa for test sets of florbetapir and florbetaben PET were 0.87 and 0.89, respectively. CONCLUSION: We suggest a one-step quantification method for amyloid PET via a deep learning model. The model is highly reliable to quantify the amyloid PET regardless of multicenter images and various radiotracers.

Comprehensive gene expression analysis for exploring the association between glucose metabolism and differentiation of thyroid cancer.

BACKGROUND: The principle of loss of iodine uptake and increased glucose metabolism according to dedifferentiation of thyroid cancer is clinically assessed by imaging. Though these biological properties are widely applied to appropriate iodine therapy, the understanding of the genomic background of this principle is still lacking. We investigated the association between glucose metabolism and differentiation in advanced thyroid cancer as well as papillary thyroid cancer (PTC). METHODS: We used RNA sequencing of 505 patients with PTC obtained from the Cancer Genome Archives and microarray data of poorly-differentiated and anaplastic thyroid cancer (PDTC/ATC). The signatures of GLUT and glycolysis were estimated to assess glucose metabolic profiles. The glucose metabolic profiles were associated with tumor differentiation score (TDS) and BRAFV600E mutation status. In addition, survival analysis of glucose metabolic profiles was performed for predicting recurrence-free survival. RESULTS: In PTC, the glycolysis signature was positively correlated with TDS, while the GLUT signature was inversely correlated with TDS. These correlations were significantly stronger in the BRAFV600E negative group than the positive group. Meanwhile, both GLUT and glycolysis signatures were negatively correlated with TDS in advanced thyroid cancer. The high glycolysis signature was significantly associated with poor prognosis in PTC in spite of high TDS. The glucose metabolic profiles are intricately associated with tumor differentiation in PTC and PDTC/ATC. CONCLUSIONS: As glycolysis was an independent prognostic marker, we suggest that the glucose metabolism features of thyroid cancer could be another biological progression marker different from differentiation and provide clinical implications for risk stratification. TRIAL REGISTRATION: Not applicable.

Infliximab biosimilar CT-P13 therapy in patients with Takayasu arteritis with low dose of glucocorticoids: a prospective single-arm study.

To evaluate the efficacy and safety of infliximab biosimilar CT-P13 in patients with active Takayasu arteritis (TAK). In this single-center open-label trial, patients with active TAK received CT-P13 at a starting dose of 5 mg/kg at weeks 0, 2, 6, and then every 8 weeks up to week 46. They were followed up until week 54. From week 14 to week 46, patients with inadequate response received increased dose of CT-P13 by 1.5 mg/kg. Concomitant prednisolone was allowed ≤ 10 mg/day. The primary efficacy end point was the achievement of partial or complete remission at week 30. All patients underwent positron emission tomography-computed tomography (PET-CT) at baseline and week 30. Twelve patients with TAK received CT-P13; one patient with protocol violation was excluded from analysis. Nine (81.8%) patients had taken concomitant prednisolone with median dose of 5.0 mg/day. At week 30, three (27.3%) patients achieved complete remission and six (54.5%) patients achieved partial remission. Statistically significant improvements in modified Indian Takayasu Clinical Activity Score (ITAS2010), ITAS-A, and serum levels of erythrocyte sedimentation rate and C-reactive protein were seen at week 30 from baseline. PET parameters were significantly reduced from baseline to week 30, including maximum standardized uptake value, target-to-vein ratio, target-to-liver ratio, and PET Vascular Activity Score. There were no serious adverse events. Treatment with CT-P13 may lead to improvement in clinical, radiographic, and serological activities with lower glucocorticoid requirement in TAK.Trial registration number NCT02457585.

Integrated 18F-FDG PET/MRI in breast cancer: early prediction of response to neoadjuvant chemotherapy.

PURPOSE: To explore whether integrated 18F-FDG PET/MRI can be used to predict pathological response to neoadjuvant chemotherapy (NAC) in patients with breast cancer. METHODS: Between November 2014 and April 2016, 26 patients with breast cancer who had received NAC and subsequent surgery were prospectively enrolled. Each patient underwent 18F-FDG PET/MRI examination before and after the first cycle of NAC. Qualitative MRI parameters, including morphological descriptors and the presence of peritumoral oedema were assessed. Quantitatively, PET parameters, including maximum standardized uptake value, metabolic tumour volume and total lesion glycolysis (TLG), and MRI parameters, including washout proportion and signal enhancement ratio (SER), were measured. The performance of the imaging parameters singly and in combination in predicting a pathological incomplete response (non-pCR) was assessed. RESULTS: Of the 26 patients, 7 (26.9%) exhibited a pathological complete response (pCR), and 19 (73.1%) exhibited a non-pCR. No significant differences were found between the pCR and non-pCR groups in the qualitative MRI parameters. The mean percentage reductions in TLG30% on PET and SER on MRI were significantly greater in the pCR group than in the non-pCR group (TLG30% -64.8 ± 15.5% vs. -25.4 ± 48.7%, P = 0.005; SER -34.6 ± 19.7% vs. -8.7 ± 29.0%, P = 0.040). The area under the receiver operating characteristic curve for the percentage change in TLG30% (0.789, 95% CI 0.614 to 0.965) was similar to that for the percentage change in SER (0.789, 95% CI 0.552 to 1.000; P = 1.000).The specificity of TLG30% in predicting pCR) was 100% (7/7) and that of SER was 71.4% (5/7). The sensitivity of TLG30% in predicting non-pCR was 63.2% (12/19) and that of SER was 84.2% (16/19). When the combined TLG30% and SER criterion was applied, sensitivity was 100% (19/19), and specificity was 71.4% (5/7). CONCLUSION: 18F-FDG PET/MRI can be used to predict non-pCR after the first cycle of NAC in patients with breast cancer and has the potential to improve sensitivity by the addition of MRI parameters to the PET parameters.

Determination of the starting dose in the first-in-human clinical trials with monoclonal antibodies: a systematic review of papers published between 1990 and 2013.

A systematic review was performed to evaluate how the maximum recommended starting dose (MRSD) was determined in first-in-human (FIH) studies with monoclonal antibodies (mAbs). Factors associated with the choice of each MRSD determination method were also identified. PubMed was searched for FIH studies with mAbs published in English between January 1, 1990 and December 31, 2013, and the following information was extracted: MRSD determination method, publication year, therapeutic area, antibody type, safety factor, safety assessment results after the first dose, and number of dose escalation steps. Seventy-nine FIH studies with mAbs were identified, 49 of which clearly reported the MRSD determination method. The no observed adverse effects level (NOAEL)-based approach was the most frequently used method, whereas the model-based approach was the least commonly used method (34.7% vs 16.3%). The minimal anticipated biological effect level (MABEL)- or minimum effective dose (MED)-based approach was used more frequently in 2011-2013 than in 1990-2007 (31.6% vs 6.3%, P=0.036), reflecting a slow, but steady acceptance of the European Medicines Agency's guidance on mitigating risks for FIH clinical trials (2007). The median safety factor was much lower for the MABEL- or MED-based approach than for the other MRSD determination methods (10 vs 32.2-53). The number of dose escalation steps was not significantly different among the different MRSD determination methods. The MABEL-based approach appears to be safer and as efficient as the other MRSD determination methods for achieving the objectives of FIH studies with mAbs faster.