Effect of hyperglycemia on brain and liver 18F-FDG standardized uptake value (FDG SUV) measured by quantitative positron emission tomography (PET) imaging

Regional brain glucose uptake following gastric bypass surgery during normo- and hypoglycemic clamp: a pilot FDG-PET study

PURPOSE

We aimed to characterize the RYGB-induced changes in the dynamics of brain glucose uptake. We addressed heterogeneity between brain regions during experimental normo- and hypoglycemia and explored associations with anthropometric and metabolic outcomes of RYGB.

METHODS

Analyses of regional brain glucose uptake were performed on 9 individuals with obesity and no diabetes, investigated with combined brain 18F-FDG-PET and fMRI during hyperinsulinemic normo- and hypoglycemic clamp, one month before and four months after RYGB. FDG clearance, reflecting glucose uptake rate, was assessed in 38 brain regions, covering all cortical areas and subcortical nuclei, during hyperinsulinemic normo- and hypoglycemia. Correlation analyses were performed to identify associations with other outcomes of RYGB.

RESULTS

FDG uptake rate during hypoglycemia was higher than during normoglycemia in all brain regions, both before and after RYGB. Moreover, in most regions and especially in cortical areas involved in inhibitory behavioral control, FDG uptake rate tended to be reduced after surgery during normoglycemia but elevated during hypoglycemia. However, these post-surgical changes in FDG uptake rate were opposite in the hypothalamus. Thus, the hypo-to-normoglycemia FDG clearance ratio tended to increase in all brain regions following RYGB, but not in the amygdala and the hypothalamus. Changes in regional FDG uptake rate after RYGB during normoglycemia were associated with weight loss and improved systemic insulin sensitivity.

CONCLUSION

Using dynamic FDG-PET, we show region-specific patterns of changes in glucose utilization following RYGB. In the hypothalamus, glucose uptake during normoglycemia tended to rise after RYGB while it was reduced in cortical regions involved in behavioral control. Following RYGB, the hypothalamus and amygdala, in contrast to other regions, displayed trends of reduced glucose uptake during hypoglycemia. These pilot results highlight the brain effects of RYGB and suggest behavioral and neuroendocrine adaptations which contribute to its antidiabetic effects.

Exploratory Dual PET imaging of [18F] fluorodeoxyglucose and [11C]acetoacetate in type 2 diabetic nonhuman primates

Despite recent advancements in imaging (amyloid-PET & tau-PET) and fluid (Aβ42/Aβ40 & Aβ42/ptau) biomarkers, the current standard for in vivo assessment of AD, diagnosis and prediction of Alzheimer's disease (AD) remains challenging. We demonstrated in nonhuman primates (NHP) that increased plasma and cerebrospinal fluid (CSF) glucose correlated with decreased CSF Aβ42 and CSF Aβ40, a hallmark of plaque promoting pathogenesis. Together, our findings demonstrate that altered glucose homeostasis and insulin resistance are associated with Aβ and amyloid in rodent and NHP models. This warranted further exploration into the dynamics of altered brain metabolism in the NHP model of T2D, cross referenced with CSF and blood-based AD markers. Preliminary dual PET ([11C]acetoacetate ([11C]AcAc) and [18F]fluorodeoxyglucose ([18F]FDG) imaging studies were conducted in an aged cohort of NHPs classified as T2D (n = 5) and pre-diabetic (n = 1) along with corresponding plasma and CSF samples for metabolite analysis. [11C]AcAc and [18F]FDG PET brain standard uptake values (SUV) were highly positively associated (r = 0.88, p = 0.02) in the T2D and pre-diabetic NHPs. Age was not significantly associated with brain SUV (age range 16.5-23.5 years old). Metabolic measures were positively correlated with brain [18F]FDG and CSF Aβ42:40 was positively correlated to fasting glucose values. Although our findings suggest moderate correlations, this study further elucidates that peripheral insulin resistance and poor glycemia control alter AD-related pathology, illustrating how T2D is a risk factor for AD.

Cerebellum/liver index on baseline 18F-FDG PET/CT to improve prognostication in post-transplant lymphoproliferative disorders: a multicenter retrospective study

BACKGROUND

Besides International Prognostic Index (IPI) score, baseline prognostic factors of post-transplant lymphoproliferative disorders (PTLD) are poorly identified due to the rarity of the disease. New indexes derived from healthy organ uptake in baseline 18F-FDG PET/CT have been studied in immunocompetent lymphoma patients. The aim of this study is to evaluate the performances of the cerebellum-to-liver uptake ratio (denoted as CLIP) as a prognostic factor for PFS and OS. This retrospective multicenter study is based on patients with PTLD included in the K-VIROGREF cohort. The previously published threshold of 3.24 was used for CLIP in these analyses.

RESULTS

A total of 97 patients was included with a majority of monomorphic diffuse large B-cell lymphoma subtype (78.3%). Both IPI score (≥ 3) and CLIP (< 3.24) were significant risk factors of PFS with corresponding hazard ratios of 2.0 (1.0-4.0) and 2.4 (1.3-4.5) respectively. For OS, CLIP was not significant and resulted in a hazard ratio of 2.6 (p = 0.059). Neither IPI score or Total Metabolic Tumor Volume reached significance for OS.

CONCLUSION

CLIP is a promising predictor of PFS and perhaps OS in PTLD. Further prospective studies are needed to confirm these results.

Comparison between an SGLT2 inhibitor and insulin in tumor-to-tissue contrasts in 18F-FDG PET imaging of diabetic mice

18F-fluorodeoxyglucose positron emission tomography (18F-FDG PET) has been widely utilized for tumor diagnosis. Hyperglycemia affects the 18F-FDG uptake and reduces tumor-to-tissue contrasts, however, ideal hypoglycemic drugs are lacking. This study compared the role of insulin with the novel widely used hypoglycemic drug, sodium-glucose cotransporter 2 (SGLT2) inhibitor, on 18F-FDG PET imaging in diabetic conditions. The streptozotocin (STZ)-induced diabetic C57BL/6N mice were inoculated with B16 (mouse melanoma) cells to establish the xenograft tumor model. After the mice had been administrated with dapagliflozin (30 mg/kg, IG) or insulin (0.75 U/kg, IP) for one hour, 9.25 MBq/10 g 18F-FDG was injected. Biodistributions were detected by gamma counting and microPET imaging. The results showed dapagliflozin did not significantly affect the 18F-FDG uptake in tumors but reduced uptake in reference tissues, resulting in a significant increase in the tumor-to-skeletal muscle ratio. Conversely, insulin increased 18F-FDG uptake in tumors without significant reduction in uptake in reference tissues; Although there was an observable improvement in tumor imaging, it did not reach significantly statistical differences. This study suggests that insulin and SGLT2 inhibitor yield comparable effects on the quality of 18F-FDG PET imaging in diabetic patients. Nevertheless, SGLT2 inhibitors would be more suitable when skeletal muscle is used as reference tissue.

Hyperpolarized [1-13C]pyruvate Magnetic Resonance Spectroscopy Shows That Agmatine Increased Lactate Production in the Brain of Type 2 Diabetic Mice

PURPOSE

Type 2 diabetes mellitus (T2DM) is associated with a 2-fold increased risk of developing Alzheimer's disease. In earlier research, agmatine has been demonstrated to alleviate diabetes symptoms and increase cognitive performance. However, it is unclear whether the improvement of cognitive function is attributable to the reduction of diabetic symptoms or its direct influence on brain metabolism. Using hyperpolarized (HP) [1-13C]pyruvate magnetic resonance spectroscopy (MRS), this study intends to evaluate the influence of agmatine on brain metabolism.

MATERIALS AND METHODS

ICR mice were fed a high-fat diet and injected with streptozotocin to develop a T2DM animal model. During a 2-week period, T2DM mice were treated with normal saline or 100 mg/kg of agmatine, and brain HP [1-13C]pyruvate MRS was performed. The effect of agmatine on lactate generation and NADH/NAD+ redox state was investigated using C6 and neuro-2a (N2a) cells.

RESULTS

As a perfusion marker, the total 13C signals in the brain of T2DM mice (p=0.07) and agmatine-treated mice (p<0.05) were reduced. The conversion constant (Kpl) from [1-13C]pyruvate to [1-13C]lactate was not distinguishable in the brains of T2DM mice but was significantly increased in the brains of agmatine-treated T2DM mice. Treating C6 and N2a cells with agmatine increased NADH/NAD+ratio and lactate generation.

CONCLUSION

Agmatine influences the NADH/NAD+ redox state in the brains of T2DM mice, which may be connected with enhanced cognitive performance and increased conversion of HP [1-13C]pyruvate to HP [1-13C]lactate.

Predictors of infectious foci on FDG PET/CT in Staphylococcus aureus bacteremia

We looked for predicting factors for the detection of infectious foci on 18F-fluorodeoxyglucose-positron emission tomography in combination with computed tomography (FDG PET/CT) among patients with Staphylococcus aureus bacteremia (SAB) who participated in an interventional study that was conducted at Rambam Health Care Campus, between July 1, 2015 and February 1, 2019. The primary outcome was an infectious focus detected by FDG PET/CT. Independent predictors for detection of focal infection were identified using univariate followed by a logistic regression multivariate analysis. We included 149 patients with 151 separate episodes of SAB who underwent FDG-PET/CT. Focal infections were detected in 107 patients (70.8%). Independent predictors for focal infection detection were community acquisition of bacteremia with odds ratio (OR) 3.03 [95% confidence interval (CI) 1.04-8.77], p-0.042 and C reactive protein (CRP) with OR 1.09 [95% CI 1.04-1.14], p < 0.001. Primary bacteremia was inversely associated with focal infection detection with OR 0.27 [0.10-0.69], p = 0.007, as were the pre-scan blood glucose levels OR 0.9 [0.98-0.99], p-0.004. The latter stayed significant in the subgroup of patients with diabetes mellitus. To conclude, patients with community-acquired bacteremia or high CRP levels should be carefully investigated for focal infection. Patients who present with primary bacteremia seem to be at low risk for focal infection.

Identification of 18F-FDG PET/CT Parameters Associated with Weight Loss in Patients with Esophageal Cancer

¹⁸F-FDG PET-CT is routinely performed as part of the initial staging of numerous cancers. Other than having descriptive, predictive and prognostic values for tumors, ¹⁸F-FDG PET-CT provides full-body data, which could inform on concurrent pathophysiological processes such as malnutrition. To test this hypothesis, we measured the ¹⁸F-FDG uptake in several organs and evaluated their association with weight loss in patients at diagnosis of esophageal cancer. Forty-eight patients were included in this retrospective monocentric study. ¹⁸F-FDG uptake quantification was performed in the brain, the liver, the spleen, bone marrow, muscle and the esophageal tumor itself and was compared between patients with different amounts of weight loss. We found that Total Lesion Glycolysis (TLG) and peak Standardized Uptake Values (SUV_peak) measured in the brain correlated with the amount of weight loss: TLG was, on average, higher in patients who had lost more than 5% of their usual weight, whereas brain SUV_peak were, on average, lower in patients who had lost more than 10% of their weight. Higher TLG and lower brain SUV_peak were associated with worse OS in the univariate analysis. This study reports a new and significant association between ¹⁸F-FDG uptake in the brain and initial weight loss in patients with esophageal cancer.

Prospective Evaluation of Quantitative F-18-FDG-PET/CT for Pre-Operative Thoracic Lymph Node Staging in Patients with Lung Cancer as a Target for Computer-Aided Diagnosis

Purpose: Pre-operative assessment of thoracic lymphonodal (LN) involvement in patients with lung cancer (LC) is crucial when choosing the treatment modality. Visual assessment of F-18-FDG-PET/CT (PET/CT) is well established, however, there is still a need for prospective quantitative data to differentiate benign from malignant lesions which would simplify staging and guide the further implementation of computer-aided diagnosis (CAD). Methods: In this prospective study, 37 patients with confirmed lung cancer (m/f = 24/13; age: 70 [52–83] years) were analyzed. All patients underwent PET/CT and quantitative data (standardized uptake values) were obtained. Histological results were available for 101 thoracic lymph nodes. Quantitative data were matched to determine cut-off values for delineation between benign vs. malignant lymph nodes. Furthermore, a scoring system derived from these cut-off values was established. Statistical analyses were performed through ROC analysis. Results: Quantitative analysis revealed the optimal cut-off values (p < 0.01) for the differentiation between benign and malignant thoracic lymph nodes in patients suffering from lung cancer. The respective areas under the curve (AUC) ranged from 0.86 to 0.94. The highest AUC for a ratio of lymph node to healthy lung tissue was 0.94. The resulting accuracy ranged from 78.2% to 89.1%. A dedicated scoring system led to an AUC of 0.93 with a negative predictive value of 95.4%. Conclusion: Quantitative analysis of F-18-FDG-PET/CT data provides reliable results for delineation between benign and malignant thoracic lymph nodes. Thus, quantitative parameters can improve diagnostic accuracy and reliability and can also facilitate the handling of the steadily increasing number of clinical examinations.

Impact of Reduced Image Noise on Deauville Scores in Patients with Lymphoma Scanned on a Long-Axial Field-of-View PET/CT-Scanner

BACKGROUND

Total body and long-axial field-of-view (LAFOV) PET/CT represent visionary innovations in imaging enabling either improved image quality, reduction in injected activity-dose or decreased acquisition time. An improved image quality may affect visual scoring systems, including the Deauville score (DS), which is used for clinical assessment of patients with lymphoma. The DS compares SUVmax in residual lymphomas with liver parenchyma, and here we investigate the impact of reduced image noise on the DS in patients with lymphomas scanned on a LAFOV PET/CT.

METHODS

Sixty-eight patients with lymphoma underwent a whole-body scan on a Biograph Vision Quadra PET/CT-scanner, and images were evaluated visually with regard to DS for three different timeframes of 90, 300, and 600 s. SUVmax and SUVmean were calculated from liver and mediastinal blood pool, in addition to SUVmax from residual lymphomas and measures of noise.

RESULTS

SUVmax in liver and in mediastinal blood pool decreased significantly with increasing acquisition time, whereas SUVmean remained stable. In residual tumor, SUVmax was stable during different acquisition times. As a result, the DS was subject to change in three patients.

CONCLUSIONS

Attention should be drawn towards the eventual impact of improvements in image quality on visual scoring systems such as the DS.

Reproducibility of [18F]FDG PET/CT liver SUV as reference or normalisation factor

INTRODUCTION

Although visual and quantitative assessments of [18F]FDG PET/CT studies typically rely on liver uptake value as a reference or normalisation factor, consensus or consistency in measuring [18F]FDG uptake is lacking. Therefore, we evaluate the variation of several liver standardised uptake value (SUV) measurements in lymphoma [18F]FDG PET/CT studies using different uptake metrics.

METHODS

PET/CT scans from 34 lymphoma patients were used to calculate SUVmaxliver, SUVpeakliver and SUVmeanliver as a function of (1) volume-of-interest (VOI) size, (2) location, (3) imaging time point and (4) as a function of total metabolic tumour volume (MTV). The impact of reconstruction protocol on liver uptake is studied on 15 baseline lymphoma patient scans. The effect of noise on liver SUV was assessed using full and 25% count images of 15 lymphoma scans.

RESULTS

Generally, SUVmaxliver and SUVpeakliver were 38% and 16% higher compared to SUVmeanliver. SUVmaxliver and SUVpeakliver increased up to 31% and 15% with VOI size while SUVmeanliver remained unchanged with the lowest variability for the largest VOI size. Liver uptake metrics were not affected by VOI location. Compared to baseline, liver uptake metrics were 15-18% and 9-18% higher at interim and EoT PET, respectively. SUVliver decreased with larger total MTVs. SUVmaxliver and SUVpeakliver were affected by reconstruction protocol up to 62%. SUVmax and SUVpeak moved 22% and 11% upward between full and 25% count images.

CONCLUSION

SUVmeanliver was most robust against VOI size, location, reconstruction protocol and image noise level, and is thus the most reproducible metric for liver uptake. The commonly recommended 3 cm diameter spherical VOI-based SUVmeanliver values were only slightly more variable than those seen with larger VOI sizes and are sufficient for SUVmeanliver measurements in future studies.

TRIAL REGISTRATION

EudraCT: 2006-005,174-42, 01-08-2008.

Regional differences in the reduction in cerebral FDG uptake induced by the ketogenic diet

BACKGROUND

The postulated benefits of the ketogenic diet in the management of multiple medical conditions have seen more patients who are in therapeutic ketosis attending 18F-FDG PET scans. This study aimed to investigate the effect of ketosis on cerebral glucose metabolism in a clinical PET scanning environment using 18F-FDG uptake as a surrogate marker.

METHODS

A retrospective audit was conducted of the brain 18F-FDG uptake in 52 patients who underwent PET scans for possible cardiac sarcoidosis or suspected intracardiac infection, following a ketogenic diet and prolonged fasting. SUVbw for whole brain and separate brain regions was compared with serum glucose and serum ketone body (beta-hydroxybutyrate) levels.

RESULTS

The expected negative association between serum glucose levels and whole brain 18F-FDG uptake was confirmed. A reduction in SUVbw due to increasing serum ketones levels was also observed that was independent of and in addition to the effects of glucose. The magnitude of the reduction in SUVbw related to serum glucose level and serum ketone level was found to be greater in the precuneus than in the cerebellum or whole brain.

CONCLUSION

In a real-world clinical PET setting, cerebral 18F-FDG uptake appears to be affected by glycaemia and ketonaemia. This means when assessing the brain, both serum glucose and ketone levels need to be considered when SUVs are used to distinguish between pathologic and physiologic states. The magnitude of this effect appears to vary between different brain regions. This regional difference should be taken into consideration when selecting the appropriate brain region for SUV normalisation, particularly when undertaking database comparison in the assessment of dementia.

Intrapatient variability of 18F-FDG uptake in normal tissues

Objectives

To investigate the effect of serum glucose level and other confounding factors on the variability of maximum standardized uptake value (SUVmax) in normal tissues within the same patient on two separate occasions and to suggest an ideal reference tissue.

Materials and Methods

We retrospectively reviewed 334 18F-FDG PET/CT scans of 167 cancer patients including 38 diabetics. All patients had two studies, on average 152 ± 68 days apart. Ten matched volumes of interest were drawn on the brain, right tonsil, blood pool, heart, lung, liver, spleen, bone marrow, fat, and iliopsoas muscle opposite third lumber vertebra away from any pathological 18F-FDG uptake to calculate SUVmax.

Results

SUVmax of the lungs and heart were significantly different in the two studies (P = 0.003 and P = 0.024 respectively). Only the brain uptake showed a significant moderate negative correlation with the level of blood glucose in diabetic patients (r = −0.537, P = 0.001) in the first study, while the SUVmax of other tissues showed negligible or weak correlation with the level of blood glucose in both studies.

The liver showed significant moderate positive correlation with body mass index (BMI) in both studies (r = .416, P = <0.001 versus r = 0.453, P = <0.001, respectively), and blood pool activity showed significant moderate positive correlation with BMI in the first study only (r = 0.414, P = <0.001). The liver and blood pool activities showed significant moderate negative correlation with 18F-FDG uptake time in first study only (r = −0.405, P-value = <0.001; and r = −0.409, P-value = <0.001, respectively).

In the multivariate analysis, the liver showed a consistent effect of the injected 18F-FDG dose and uptake duration on its SUVmax on the two occasions. In comparison, spleen and muscle showed consistent effect only of the injected dose on the two occasions.

Conclusion

The liver, muscle, and splenic activities showed satisfactory test/retest stability and can be used as reference activities. The spleen and muscle appear to be more optimal reference than the liver, as it is only associated with the injected dose of 18F-FDG.

Evaluation of 18F-fluorodeoxyglucose uptake of beagle dogs for different durations of isoflurane anesthesia

¹⁸F-fluorodeoxyglucose (FDG) positron emission tomography (PET) is used for tumor evaluation. In veterinary medicine, anesthesia is an essential tool during the PET scanning process. However, the changes in FDG uptake in dogs that have undergone anesthesia for a longer duration have not been studied. This study aimed to analyze the influence of isoflurane anesthesia on FDG uptake in dogs undergoing PET. A crossover design was implemented by exposing 3 groups of 6 dogs to different durations of anesthesia (60, 90, and 150 minutes). Inhalation anesthesia was maintained throughout the scanning process (30 minutes) and FDG was injected 1 hour before the start of the PET scan. The standard uptake value of FDG was obtained for the 7 gross structures (whole brain, lung, salivary gland, liver, spleen, mediastinal blood pool, and kidney cortex) as well as for the 7 intracranial structures (frontal, parietal, temporal and occipital lobes, cerebellum, brain stem, and caudal colliculus). The whole brain and intracranial structures showed significantly lower FDG uptake in dogs with a longer duration of anesthesia, whereas other gross structures did not. Our results suggest that the duration of anesthesia should be considered when evaluating the uptake of FDG by the brain.

Hypermetabolism of the spleen or bone marrow is an additional albeit indirect sign of infective endocarditis at FDG-PET

PURPOSE

This study aimed at determining the diagnostic implications of indirect signs of infection at FDG-PET-i.e., hypermetabolisms of the spleen and/or bone marrow (HSBM)-when documented in patients with known or suspected infective endocarditis (IE).

METHODS

HSBM were defined by higher mean standardized uptake values comparatively to that of the liver on FDG-PET images from patients with a high likelihood of IE and prospectively included in a multicenter study.

RESULTS

Among the 129 included patients, IE was ultimately deemed as definite in 88 cases. HSBM was a predictor of definite IE (P = 0.014; odds ratio (OR) 3.2), independently of the criterion of an abnormal cardiac FDG uptake (P = 0.0007; OR 9.68), and a definite IE was documented in 97% (29/30) of patients showing both HSBM and abnormal cardiac uptake, 78% (7/9) of patients with only abnormal cardiac uptake, 67% (42/63) of patients with only HSBM, and 37% (10/27) of patients with neither one.

CONCLUSION

In this cohort with a high likelihood of IE, HSBM is an additional albeit indirect sign of IE, independently of the criterion of an abnormal cardiac uptake, and could reinforce the suspicion of IE in the absence of any other infectious, inflammatory, or malignant disease.

A reduced physiological 18F-fluorodeoxyglucose uptake in the brain and liver caused by malignant lymphoma being deprived of the tracer

Purpose : To investigate whether or not the physiological brain and liver FDG uptake are decreased in patients with highly accelerated glycolysis lesions. Methods : We retrospectively analyzed 51 patients with malignant lymphoma. We compared the FDG uptake in the brain and liver of the patients with that in a control group. In 24 patients with a complete response (CR) or partial response (PR) to treatment, we compared the brain and liver uptake before and after treatment. Results : The maximum standardized uptake value (SUVmax) and total glycolytic volume (TGV) of the brain as well as the SUVmax and mean standardized uptake value (SUVmean) of the liver in malignant lymphoma patients were 13.1 ± 2.3, 7386.3 ± 1918.4, 3.2 ± 0.5, and 2.3 ± 0.4, respectively ; in the control group, these values were 14.9 ± 2.4, 8566.2 ± 1659.5, 3.4 ± 0.4, and 2.5 ± 0.3, respectively. The SUVmax and TGV of the brain and the SUVmean of the liver in malignant lymphoma patients were significantly lower than the control group. The SUVmax and TGV of the brain after treatment were significantly higher than before treatment. Both the SUVmax and SUVmean of liver after treatment were higher than before treatment, but not significant. Conclusion : A decreased physiological brain and liver FDG uptake is caused by highly accelerated lesion glycolysis. J. Med. Invest. 68 : 181-185, February, 2021.

Imaging Acute Metabolic Changes in Patients with Mild Traumatic Brain Injury Using Hyperpolarized [1-13C]Pyruvate

Traumatic brain injury (TBI) involves complex secondary injury processes following the primary injury. The secondary injury is often associated with rapid metabolic shifts and impaired brain function immediately after the initial tissue damage. Magnetic resonance spectroscopic imaging (MRSI) coupled with hyperpolarization of ¹³C-labeled substrates provides a unique opportunity to map the metabolic changes in the brain after traumatic injury in real-time without invasive procedures. In this report, we investigated two patients with acute mild TBI (Glasgow coma scale 15) but no anatomical brain injury or hemorrhage. Patients were imaged with hyperpolarized [1-¹³C]pyruvate MRSI 1 or 6 days after head trauma. Both patients showed significantly reduced bicarbonate (HCO₃^–) production, and one showed hyperintense lactate production at the injured sites. This study reports the feasibility of imaging altered metabolism using hyperpolarized pyruvate in patients with TBI, demonstrating the translatability and sensitivity of the technology to cerebral metabolic changes after mild TBI.

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Clinical translation of hyperpolarized pyruvate to TBI was demonstrated

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Patients with mild TBI were imaged with hyperpolarized [1-¹³C]pyruvate

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Altered lactate and HCO₃^– production in the brain nearest the site of trauma

Blood pool activity on F-18 FDG PET/CT as a possible imaging biomarker of metabolic syndrome

Association of blood pool (BP) and adipose tissue activity from F-18 fluorodeoxyglucose positron-emission tomography/computed tomography (FDG PET/CT) with the parameters of metabolic syndrome (MetS) and different MetS/obesity types were investigated. 245 subjects underwent FDG PET/CT scan for health check-ups were investigated retrospectively. Associations of BP (BP SUV: SUV_max, SUV_mean), visceral (VAT SUV), and subcutaneous adipose tissue (SAT SUV) activity with parameters of MetS, body mass index (BMI), and lipid profiles were analyzed. MetS/obesity types were subdivided into metabolically healthy obese (MHO) and metabolically unhealthy obese (MUO). BP SUV was higher in subjects with MetS (t-test, P < 0.005), and was associated with MetS from multivariable binary logistic regression (OR 5.232 P = 0.010). BP SUV was statistically higher in MUO than in MHO (P < 0.05) along with blood pressure, triglycerides, and HDL-cholesterol. Multivariable binary logistic regression analysis showed MUO had higher blood pressure and BP SUV, while lower HDL-cholesterol relative to MHO after adjusting for triglycerides.

Diagnostic accuracy of 18F-FDG-PET in abdominal sepsis in rats

Purpose

The objective of this study was to investigate the accuracy of 18F-FDG-PET in the diagnosis of multibacterial abdominal sepsis by cecum ligation and puncture (CLP) in rats.

Methods

Adult Wistar rats ( Rattus norvegicus ), weighing 227±35g, were allocated into a sepsis group by CLP (n=10) and sham group (n=10). 18F-FDG-PET using microPET was performed on all rats after 24 hours.

Results

All animals survived for postoperative 24h. The abdomen/liver ratio of the standardized uptake value (SUV) percentage was significantly higher in the sepsis group than in the sham (p=0.004). The ROC curve showed an accuracy of 18F-FDG-PET to detect abdominal sepsis of 88.9% (p=0.001), sensitivity of 90% and specificity of 88.9%. When a cut-off point of 79% of the ratio between the SUV on the abdominal region and liver was established, the sensitivity was 90%, specificity of 88.9%; positive and negative predictive values of 90.0% and 88.9%, respectively.

Conclusions

The diagnostic accuracy of 18F-FDG-PET in rats with abdominal sepsis was significantly high. It was also demonstrated the predictive ability of the abdomen/liver SUV ratio to diagnose abdominal sepsis. These findings may have implications for the clinical setting, locating septic foci with PETscan.

Assessment of Brain Glucose Metabolism Following Cardiac Arrest by [18F]FDG Positron Emission Tomography

BACKGROUND

Cardiac arrest (CA) patients who survived by cardiopulmonary resuscitation (CPR) can present different levels of neurological deficits ranging from minor cognitive impairments to persistent vegetative state and brain death. The pathophysiology of the resulting brain injury is poorly understood, and whether changes in post-CA brain metabolism contribute to the injury are unknown. Here we utilized [¹⁸F]fluorodeoxyglucose (FDG)-Positron emission tomography (PET) to study in vivo cerebral glucose metabolism 72 h following CA in a murine CA model.

METHODS

Anesthetized and ventilated adult C57BL/6 mice underwent 12-min KCl-induced CA followed by CPR. Seventy-two hours following CA, surviving mice were intraperitoneally injected with [¹⁸F]FDG (~ 186 µCi/200 µL) and imaged on Molecubes preclinical micro-PET/computed tomography (CT) imaging systems after a 30-min awake uptake period. Brain [¹⁸F]FDG uptake was determined by the VivoQuant software on fused PET/CT images with the 3D brain atlas. Upon completion of Positron emission tomography (PET) imaging, remaining [¹⁸F]FDG radioactivity in the brain, heart, and liver was determined using a gamma counter.

RESULTS

Global increases in brain [¹⁸F]FDG uptake in post-CA mice were observed compared to shams and controls. The median standardized uptake value of [¹⁸F]FDG for CA animals was 1.79 versus sham 1.25 (p < 0.05) and control animals 0.78 (p < 0.01). This increased uptake was consistent throughout the 60-min imaging period and across all brain regions reaching statistical significance in the midbrain, pons, and medulla. Biodistribution analyses of various key organs yielded similar observations that the median [¹⁸F]FDG uptake for brain was 7.04%ID/g tissue for CA mice versus 5.537%ID/g tissue for sham animals, p < 0.05).

CONCLUSIONS

This study has successfully applied [¹⁸F]FDG-PET/CT to measure changes in brain metabolism in a murine model of asystolic CA. Our results demonstrate increased [¹⁸F]FDG uptake in the brain 72 h following CA, suggesting increased metabolic demand in the case of severe neurological injury. Further study is warranted to determine the etiology of these changes.

FDG-PET/CT imaging findings of hepatic tumors and tumor-like lesions based on molecular background

The usefulness of whole-body 18-fluoro-2-deoxyglucose (FDG)-fluorodeoxyglucose positron emission (PET)/computed tomography (CT) is established for assessment of disease staging, detection of early disease recurrence, therapeutic evaluation, and predicting prognosis in various malignancies; and for evaluating the spread of inflammation. However, the role of FDG-PET/CT for the liver is limited because CT and magnetic resonance imaging (MRI) can provide an accurate diagnosis of most tumors. In addition, in other potentially useful roles there are several pitfalls in the interpretation of FDG uptake in PET/CT imaging. Accurate evaluation demands knowledge of the FDG uptake of each lesion, including potential negative and positive uptakes, and requires an understanding of the underlying background of the molecular mechanisms. The degree of FDG uptake is dependent on cellular metabolic rate and the expression of glucose transporter, hexokinase, and glucose-6-phosphatase, which in turn are closely affected by biological characteristics such as pathological category (e.g., adenocarcinoma, squamous cell carcinoma, small cell cancer, transitional cell cancer, neuroendocrine tumor, sarcoma, lymphoma), tumor differentiation, histological behavior (e.g., solid, cystic, mucinous), and intratumoral alterations (e.g., necrosis, degeneration, hemorrhage). Correlation with the CT and MRI findings, which also precisely depict the pathological findings, is important to avoid misdiagnosis.

Effects of Fever on 18F-FDG Distribution In Vivo: a Preliminary Study

PURPOSE

Elevated body temperature might change glucose metabolism in human organs. The purpose of this study is to explore ¹⁸F-FDG distribution in febrile patients on the day of ¹⁸F-FDG PET/CT scanning and compare it with patients with a normal temperature.

PROCEDURES

¹⁸F-FDG PET/CT was performed on 69 febrile patients and 82 patients with a normal temperature. Patient sociodemographic data, blood glucose levels before PET/CT, body temperature on the day of the exam, and laboratory test results were collected. Maximal standard uptake values (SUV_max) in the brain, mediastinal blood pool, liver, spleen, and the bone marrow were compared.

RESULTS

Compared with the controls, SUV_max of the febrile patients was significantly lower in the brain, mediastinal blood pool, and the liver (p < 0.01), and higher in the spleen and bone marrow (p < 0.01). In the febrile group, SUV_max was not significantly different between the FDG burden and non-FDG burden patients (p > 0.05). Body temperature was found negatively correlated with SUV_max in the brain (r = - 0.646), mediastinal blood pool (r = - 0.530), and the liver (r = - 0.384), and positively correlated with the SUV_max in the spleen (r = 0.592) and bone marrow (r = 0.651). Multivariate linear regression established body temperature on the day of PET/CT as an independent affecting factor (p < 0.01) for the SUV_max in the brain, mediastinal blood pool, liver, spleen, and bone marrow. The SUV in the brain, liver, and mediastinal blood pool remained different (p < 0.05) after corrected with the SUV_max in the blood pool or liver.

CONCLUSIONS

Fever influences ¹⁸F-FDG distribution in multiple human tissues and organs. Altered ¹⁸F-FDG distribution in vivo might affect results of disease lesion detection and tumor therapy response assessment. Correction with blood pool or liver SUV fails to cancel the effects of fever. The day of fever should be avoided for PET/CT scan, especially in assessing tumor therapy response.

18F-FLUORODEOXYGLUCOSE PET/CT CAN BE AN ALTERNATIVE METHOD TO ASSESSMENT OF INSULIN RESISTANCE

BACKGROUND

Insulin resistance is routinely measured by homeostasis model assessment of insulin resistance (HOMA-IR).Positron emission tomography of 18F-fluorodeoxyglucose combined with computed tomography (18F-FDG PET/CT) is a valuable assessment tool for patients with cancer or staging tumors. 18F-FDG PET/CT imaging can also be utilised to detect the metabolic activity of glucose in the adipose tissue, liver and muscles. The aim of this study was to determine insulin sensitivity in the liver, muscle visceral adipose and subcutaneous adipose tissue separately via18F-FDG PET/CT.

MATERIALS AND METHOD

Sixty three adult patients who underwent whole body 18F-FDG PET/CT scanning for clinical purposes (diagnosis or staging of cancer) between July and August of 2016 were included in the study. Patients were divided into two groups according to their BMI (Group 1: BMI<25kg/m², Group 2: BMI>25kg/m²). HOMA-IR,fasting glucose,insulin, triglycerides, total cholesterol, HDL levels were measured. We calculated SUV as the tissue activity of the ROI (MBq/g)/(injected dose [MBq]/ body weight [g]) on PET images and measured the maximum SUVs (SUVmax) of visceral adipose tissue (VAT) and subcutaneous adipose tissue (SAT),liver and rectus muscle ROIs (2 cm). SUV corrected by blood glucose level (SUVgluc) was calculated as SUVmax×blood glucose level/100. Student-t test, Chi-square test and Pearson correlation test were used for statistical analysis.

RESULTS

Mean glucose,insulin,HOMA-IR levels of the group-2 were statistically higher than of group-1. Muscle SUVmax and liver SUVmax of group-1 were statistically higher than of group-2. Muscle SUVgluc of group-1 was statistically higher than of group-2. HOMA-IR was negatively correlated with both SUVmax(r=-0.340, p=0.01) and muscle SUVmax(r=-0.373, p=0.005).

CONCLUSION

18F-FDG PET/CT has shown that the muscle tissue maximum FDG uptake was lower in the insulin resistance group. Therefore, 18-FDG PET/CT could be a valuable tool for diagnosing insulin resistance.

Assessing the Effect of Various Blood Glucose Levels on 18F-FDG Activity in the Brain, Liver, and Blood Pool

Studies have extensively analyzed the effect of hyperglycemia on ¹⁸F-FDG uptake in normal tissues and tumors. In this study, we measured SUV in the brain, liver, and blood pool in normoglycemia, hyperglycemia, and hypoglycemia to understand the effect of blood glucose on ¹⁸F-FDG uptake and to develop a formula to correct SUV. Methods: Whole-body ¹⁸F-FDG PET/CT images of adults were selected for analysis. Brain SUV_max, blood-pool SUV_mean, and liver SUV_mean were measured at blood glucose ranges of 61-70, 71-80, 81-90, 91-100, 101-110, 111-120, 121-130, 131-140, 141-150, 151-160, 161-170, 171-180, 181-190, 191-200, and 201 mg/dL and above. At each blood glucose range, 10 PET images were analyzed (total, 150). The mean (±SD) SUV of the brain, liver, and blood pool at each blood glucose range was calculated, and blood glucose and SUV curves were generated. Because brain and tumors show a high expression of glucose transporters 1 and 3, we generated an SUV correction formula based on percentage reduction in brain SUV_max with increasing blood glucose level. Results: Mean brain SUV_max gradually decreased with increasing blood glucose level, starting after a level of 110 mg/dL. The approximate percentage reduction in brain SUV_max was 20%, 35%, 50%, 60%, and 65% at blood glucose ranges of 111-120, 121-140, 141-160, 161-200, and 201 mg/dL and above, respectively. In the formula we generated, measured SUV_max is multiplied by a reduction factor of 1.25, 1.5, 2, 2.5, and 2.8 for the blood glucose ranges of 111-120, 121-140, 141-160, 161-200, and 201 mg/dL and above, respectively, to correct SUV. Brain SUV_max did not differ between hypoglycemic and normoglycemic patients (P > 0.05). SUV_mean in the blood pool and liver was lower in hypoglycemic patients (P < 0.05) and did not differ between hyperglycemic (P > 0.05) and normoglycemic patients. Conclusion: Hyperglycemia gradually reduces brain ¹⁸F-FDG uptake, starting after a blood glucose level of 110 mg/dL. Hyperglycemia does not affect ¹⁸F-FDG activity in the liver or blood pool. Hypoglycemia does not seem to affect brain ¹⁸F-FDG uptake but appears to reduce liver and blood-pool activity. The simple formula we generated can be used to correct SUV in hyperglycemic adults in selected cases.

Diabetes Mellitus-Related Fractional Glucose Uptake in Men and Women Imaged With 18F-FDG PET-CT

CONTEXT

Cohort studies show that cognitive dysfunction and both vascular and Alzheimer's dementia are more common in patients with type 2 diabetes mellitus (T2DM).

OBJECTIVE

To review and compare brain volume and 18F-fluorodeoxyglucose (FDG) uptake in brain of individuals age 60 to 70 years with or without type 2 diabetes.

DESIGN

We searched 620 medical records for negative 18FDG PET-CT scans obtained during 33 months. Records showing history of cognitive impairment, Alzheimer's disease, neurologic disorders, any history of brain atrophy, or documented cerebral infarction on neuroimaging were excluded from the study.

RESULTS

A total of 119 medical records met the inclusion criteria. Data from 63 women and 56 men (without T2DM, 86; with T2DM, 33) were analyzed. Brain volume was larger in men than women (mean ± SD, 1411 ± 225 cm3 vs 1325 ± 147 cm3, respectively; P = 0.02), but men had a significantly lower fractional glucose uptake (SUVgluc), calculated as fasting blood glucose × SUVmax. [median (minimum, maximum), 63.6 (34.6, 126.6) vs 70.0 (36.4, 134.3); P = 0.02]. Brain volume was also larger in persons without T2DM than in those with T2DM (1392 ± 172 cm3 vs 1269 ± 183 cm3; P < 0.001), but SUVgluc was similar between these groups. Brain volume correlated with SUVgluc in both men and women overall (P < 0.001) but not in men and women with T2DM (P = 0.20 and 0.36, respectively).

CONCLUSION

In men without T2DM, median brain volume was larger and fractional glucose uptake was less than in women without T2DM. In men and women with T2DM, brain volume and fractional glucose uptake were similar. The findings support the hypothesis that fractional glucose uptake becomes impaired in men with T2DM.

Effects of plasma glucose levels on regional cerebral 18F-fluorodeoxyglucose uptake: Implications for dementia evaluation with brain PET imaging

Purpose:

Hyperglycemia affects FDG uptake in the brain, potentially emulating Alzheimer’s disease in normal individuals. This study investigates global and regional cerebral FDG uptake as a function of plasma glucose in a cohort of patients.

Methods:

120 consecutive male patients with FDG PET/CT for initial oncologic staging (July-Dee 2015) were reviewed. Patients with dementia, cerebrovascular accident, structural brain lesion, prior oncology treatment or high metabolic tumor burden (recently shown affecting brain FDG uptake) were excluded. 53 (24 nondiabetic) eligible patients (age 65.7 ± 2.8 mean ± SE) were analyzed with parametric computer software, MIMneuro™. Regional Z-scores were evaluated as a function of plasma glucose and age using multi variable linear mixed effects models with false discovery analysis adjusting for multiple comparisons. If the regression slope was significantly (p < 0.05) different than zero, hyperglycemia effect was present.

Results:

There was a negative inverse relationship (p < 0.001) between global brain FDG uptake and hyperglycemia. No regional hyperglycemia effect on uptake were present when subjects were normalized using pons or cerebellum. However, regional hyperglycemia effects were seen (p < 0.047–0.001) when normalizing by the whole brain. No obvious pattern was seen in the regions affected. Age had a significant effect using whole brain normalization (p < 0.04–0.01).

Conclusions:

Cortical variation in FDG uptake were identified when subjects were hyperglycemic. However, these variations didn’t fit a particular pattern of dementia and the severity of the affect is not likely to alter clinical interpretation.

Hyperpolarized [1-13C] pyruvate MR spectroscopy detect altered glycolysis in the brain of a cognitively impaired mouse model fed high-fat diet

Higher dietary intakes of saturated fatty acid increase the risk of developing Alzheimer’s disease and dementia, and even in people without diabetes higher glucose levels may be a risk factor for dementia. The mechanisms causing neuronal dysfunction and dementia by consuming high-fat diet degrading the integrity of the blood-brain barrier (BBB) has been suggested but are not yet fully understood, and metabolic state of the brain by this type of insult is still veiled. The objective of this study was to investigate the effect of high-fat diet on the brain metabolism by a multimodal imaging method using the hyperpolarizedcarbon 13 (¹³C)-pyruvate magnetic resonance (MR) spectroscopy and dynamic contrast-enhanced MR imaging in conjunction with the biochemical assay and the behavior test in a mouse model fed high-fat diet (HFD). In mice were fed 60% HFD for 6 months, hyperpolarized [1-¹³C] pyruvate MR spectroscopy showed decreased perfusion (p < 0.01) and increased conversion from pyruvate to lactate (p < 0.001) in the brain. The hippocampus and striatum showed the highest conversion ratio. The functional integrity of the blood-brain barrier tested by dynamic contrast-enhanced MR imaging showed no difference to the control. Lactate was increased in the cortex (p < 0.01) and striatum (p < 0.05), while PDH activity was decreased in the cortex (p < 0.01) and striatum (p < 0.001) and the phosphorylated PDH was increased in the striatum (p < 0.05). Mice fed HFD showed less efficiency in learning memory compared with control (p < 0.05). To determine whether hyperpolarized ¹³C-pyruvate magnetic resonance (MR) spectroscopy could detect a much earier event in the brain. Mice fed HFD for 3 months did not show a detectable cognitive decline in water maze based learning memory. Hyperpolarized [1-¹³C] pyruvate MR spectroscopy showed increased lactate conversion (P < .001), but no difference in cerebral perfusion. These results suggest that the increased hyperpolarized [1-¹³C] lactate signal in the brain of HFD-fed mice represent that altered metabolic alteration toward to glycolysis and hypoperfusion by the long-term metabolic stress by HFD further promote to glycolysis. The hyperpolarized [1-¹³C] pyruvate MR spectroscopy can be used to monitor the brain metabolism and will provide information helpful to understand the disease process.

Management of Diabetes Mellitus Before 18F-Fluorodeoxyglucose PET/CT: A Nationwide Patient-Centered Assessment of Approaches to Examination Preparation

PURPOSE

The aim of this study was to perform, from the patient's point of view, a nationwide assessment of nuclear medicine practices regarding diabetic management before ¹⁸F-fluorodeoxyglucose (FDG) PET/CT for oncologic indications.

METHODS

This prospective observational study was exempt from institutional review board oversight. Sixty-five nuclear medicine scheduling lines (33 academic, 32 private practice, 12-17 in each of the five US regions) were called using a prewritten script under the guise of a nonexpert patient's family member about scheduling a patient with diabetes with "cancer" for FDG PET/CT. Each center was called three times on three different days. The following data were collected: (1) blood glucose threshold for rescheduling an examination, (2) when or if to stop various medications, (3) fasting requirements, and (4) time-of-day scheduling preferences. Withheld information was not specifically requested. Descriptive statistics were calculated.

RESULTS

There were 195 phone calls (mean duration, 2.9 min; range, 2-6 min). Relevant information was often withheld; withholding rates were as follows: blood glucose threshold, 71% (138 of 195); short-acting insulin instructions, 30% (59 of 195); long-acting insulin instructions, 99% (193 of 195); metformin instructions, 88% (179 of 195); fasting duration, 37% (72 of 195); and time-of-day scheduling preference, 91% (177 of 195). Mean provided data were as follows: blood glucose threshold, 195 mg/dL (range, 150-210 mg/dL); short-acting insulin withholding, 4.9 hours (range, 4-8 hours); long-acting insulin withholding, 12 hours (range, 12-24 hours); fasting duration, 5 hours (range, 4-8 hours); and preferred examination time, 91% (177 of 195). When specified (n = 18), morning scheduling was preferred (8% [15 of 195] versus 2% [3 of 195]).

CONCLUSIONS

Diabetes-specific information is commonly withheld by nuclear medicine call centers throughout the United States when discussing oncologic FDG PET/CT despite local and national policies indicating its importance.

Effects of Tumor Burden on Reference Tissue Standardized Uptake for PET Imaging: Modification of PERCIST Criteria

Purpose To examine the effect metabolic burden (tumor and/or cardiac myocyte uptake) has on fluorine 18 fluorodeoxyglucose (FDG) distribution in organs and tissues of interest. Materials and Methods Positron emission tomographic (PET)/computed tomographic (CT) scans at the Ann Arbor Veterans Affairs hospital from January to July 2015 were reviewed. A total of 107 scans (50 patients; mean age, 64.3 years ± 13.2 [standard deviation]) had metabolic tissue burden assessed by using total lesion glycolysis (TLG) obtained from autosegmentation of the tumor and/or cardiac tissue. Standardized uptake value (SUV) and subsequent normalized SUV uptake in target organs and tissues were compared with 436 FDG PET/CT scans previously reported in 229 patients as a function of TLG to describe the effect(s) that metabolic burden has on reference tissue (blood pool, liver, and brain) FDG uptake. Subsequent regression by using linear mixed-effects models was used. If the slope of the regression was significantly (P < .05) different than zero, then an effect from TLG was present. Results There was a negative inverse relationship (P < .0001) between FDG uptake within reference tissues (blood pool, liver, and brain) and TLG in comparison to the study population at similar blood glucose levels. This TLG effect was no longer statistically significant (P > .05) when FDG uptake was normalized to a reference tissue (eg, blood pool or liver). Conclusion Metabolic tissue burden can have a significant effect on SUV measurements for PET imaging. This effect can be mitigated by normalizing FDG uptake to a reference tissue. ^© RSNA, 2018.

Effects of blood glucose level on 18F-FDG uptake for PET/CT in normal organs: A systematic review

Purpose

To perform a systematic review of the effect of blood glucose levels on 2-Deoxy-2-[18F]fluoro-D-glucose (18F-FDG) uptake in normal organs.

Methods

We searched the MEDLINE, EMBASE and Cochrane databases through 22 April 2017 to identify all relevant studies using the keywords “PET/CT” (positron emission tomography/computed tomography), “standardized uptake value” (SUV), “glycemia,” and “normal.” Analysis followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses recommendations. Maximum and mean SUVs and glycemia were the main parameters analyzed. To objectively measure the magnitude of the association between glycemia and 18F-FDG uptake in different organs, we calculated the effect size (ES) and the coefficient of determination (R²) whenever possible.

Results

The literature search yielded 225 results, and 14 articles met the inclusion criteria; studies included a total of 2714 (range, 51–557) participants. The brain SUV was related significantly and inversely to glycemia (ES = 1.26; R² 0.16–0.58). Although the liver and mediastinal blood pool were significantly affected by glycemia, the magnitudes of these associations were small (ES = 0.24–0.59, R² = 0.01–0.08) and negligible (R² = 0.02), respectively. Lung, bone marrow, tumor, spleen, fat, bowel, and stomach 18F-FDG uptakes were not influenced by glycemia. Individual factors other than glycemia can also affect 18F-FDG uptake in different organs, and body mass index appears to be the most important of these factors.

Conclusion

The impact of glycemia on SUVs in most organs is either negligible or too small to be clinically significant. The brain SUV was the only value largely affected by glycemia.

Effects of blood glucose level on 18F fluorodeoxyglucose (18F-FDG) uptake for PET/CT in normal organs: an analysis on 5623 patients

Our purpose was to evaluate the effect of glycemia on ¹⁸F-FDG uptake in normal organs of interest. The influences of other confounding factors, such as body mass index (BMI), diabetes, age, and sex, on the relationships between glycemia and organ-specific standardized uptake values (SUVs) were also investigated. We retrospectively identified 5623 consecutive patients who had undergone clinical PET/CT for oncological indications. Patients were stratified into groups based on glucose levels, measured immediately before ¹⁸F-FDG injection. Differences in mean SUVmax values among glycemic ranges were clinically significant only when >10% variation was observed. The brain was the only organ that presented a significant inverse relationship between SUVmax and glycemia (p < 0.001), even after controlling for diabetic status. No such difference was observed for the liver or lung. After adjustment for sex, age, and BMI, the association of glycemia with SUVmax was significant for the brain and liver, but not for the lung. In conclusion, the brain was the only organ analyzed showing a clinically significant relationship to glycemia after adjustment for potentially confounding variables. The lung was least affected by the variables in our model, and may serve as an alternative background tissue to the liver.

Hyperglycemia during first-line R-CHOP or dose adjusted R-EPOCH chemotherapy for non-Hodgkin lymphoma is prevalent and associated with chemotherapy alteration - a retrospective study

High-dose glucocorticoids such as prednisone are combined with cytotoxic chemotherapy in the R-CHOP or dose adjusted R-EPOCH regimens used for non-Hodgkin lymphoma (NHL). In this retrospective study, our primary objective was to evaluate the incidence of hyperglycemia during first-line R-CHOP or DA-EPOCH-R. The secondary objectives were to evaluate the incidence of chemotherapy alteration and overall survival in those with and without hyperglycemia. One hundred and sixty patients were eligible. We found that 47% of all patients had at least one hyperglycemic episode and hyperglycemia was associated with chemotherapy alteration (p = .028). Multivariate analysis revealed international prognostic index (IPI) ≥ 3 (p = .045) and chemotherapy alteration (p = .001) were associated with decreased overall survival. We conclude that hyperglycemia is common during first-line NHL treatment with R-CHOP or DA-EPOCH-R, even in the absence of known diabetes and is associated with alterations of chemotherapy. Baseline pre-PET scan fasting blood glucose of 100 mg/dL or higher may predict hyperglycemia during therapy.