Comparison of muscle activity, strength, and balance, before and after a 6-month training using the FIFA11+ program (part 2)

BACKGROUND

Sports injury prevention training programs have been reported to be effective in decreasing the incidence of injuries. The aim of this study was to evaluate the effects of a 6-month training period, using part 2 of the FIFA11+ program (the Fédération Internationale de Football), on the activation and strength of core and lower limb muscles and on static and dynamic balance performance.

STUDY DESIGN

Case series; level of evidence, 4.

METHODS

Eight college male soccer players, aged mean 20.4 ± 0.5 years old, completed the FIFA11+ program at least three times per week for 6 months. The following variables were measured both before and after the 6-month training program: activities of more than 30 muscles (core and lower limb muscles), measured using the standardized uptake values of 18F-fluorodeoxyglucose on positron emission tomography; isokinetic strength of the knee flexor and extensor and hip abductor muscles, measured at 60° s^-1; static balance over a 60-s period, measured using a gravicorder; and dynamic balance, measured using the star excursion balance test.

RESULTS

Training improved the activity levels of core (obliquus externus abdominis and erector spinae) and lower limb (tibialis anterior) muscles (p ≤ 0.03), corrected the between-limb difference in the activation of the semimembranosus and improved dynamic balance, with a greater training effect on the nondominant limb (p ≤ 0.02). Training also improved the knee flexor force of the nondominant lower limb (p = 0.02).

CONCLUSION

Routine performance of the FIFA11+ program can improve the activation of core and lower limb muscles, with a concomitant improvement in dynamic balance. These improvements could be beneficial in lowering the risk of sports-related injuries.

18F-fluorodeoxyglucose positron emission tomography-computed tomography scan after gastric endoscopy in those who present with non-specific symptoms, is it necessary or not?

Background and Aims:

Retrospectively analyze the sensitivity of ¹⁸F-fluorodeoxyglucose positron emission tomography-computed tomography (¹⁸F-FDG PET-CT) in the diagnosis of gastric malignancy compared with gastric endoscopy in persons with nonspecific symptoms and evaluate the necessity of ¹⁸F-FDG PET-CT scan before surgery.

Materials and Methods:

A total of 53 patients with gastric malignancy proven by surgery and pathology were enrolled in the study. All the patients underwent gastric endoscopy and PET-CT scan before surgery. And the PET-CT images were interpreted by the observers who were blinded to the results of the gastric endoscopy. The sensitivity of gastric endoscopy, ¹⁸F-FDG PET-CT, and serum tumor markers in the diagnosis of gastric malignancy were calculated ultimately.

Results:

Of 53 gastric malignancy patients, five cases were proven to be false-negative detected by gastric endoscopy, and the sensitivity of which was 90.57%. The sensitivity of PET scan alone was 86.79%, which was observed no significant difference to that of gastric endoscopy diagnosis, P = 0.54. While all of the patients had been detected positive on PET-CT images, the sensitivity of which was significantly higher than that of the gastric endoscopy diagnosis or that of the serum tumor markers, P < 0.001. And the FDG uptake was positively correlated with the depth of the cancer invasion into the gastric wall (P < 0.0001) and the degree of lymph nodes infiltration (P = 0.02). It also various from different differentiation degree significantly, P = 0.04.

Conclusions:

¹⁸F-fluorodeoxyglucose PET-CT could detect gastric carcinoma in persons with nonspecific symptoms which showed negative in gastric endoscopy. And it is necessary to be aware of the possibility of gastric malignancy when the result of PET-CT scan is positive.

Molecular imaging in immuno-oncology: current status and translational perspectives

Introduction: Only 20-40% of patients respond to therapy with immune checkpoint inhibitors (ICIs). Therefore, the early identification of subjects that can benefit from such therapeutic regimen is mandatory. Areas covered: The immunobiological mechanisms of ICIs are briefly illustrated. Furthermore, the limitations of traditional radiological approaches are covered. Then, the pros and cons of molecular imaging through positron emission computed tomography (PET/CT) are reviewed, with a particular focus on ¹⁸f-fluorodeoxyglucose (¹⁸F-FDG) and PET-derived metabolic parameters. Lastly, translational perspective of radiopharmaceuticals others than ¹⁸F-FDG such as ⁸⁹zirconium (⁸⁹Zr) or fluorine-18 (¹⁸F) labeled monoclonal antibodies (e.g.⁸⁹Zr-atezolizumab, ⁸⁹Zr-nivolumab) binding to specific biomarkers are discussed. Expert opinion: Molecular imaging presents a prominent role for the management of oncological patients treated with ICIs. Preliminary clinical data indicate that PET/CT with ¹⁸F-FDG is useful for assessing the response to treatment and for the imaging of immune-related adverse effects. Nevertheless, the methodological approach (iPERCIST, PERCIMT, or others) to be used for an optimal diagnostic accuracy and patients' evaluation is still a debated issue. PET/CT with radioligands directed toward ICIs biomarkers, although is still in a translational phase, holds the promise of accurately predicting the response to treatment and revealing the acquired resistance to immunotherapy.

Prevalence of newly diagnosed sarcoidosis in patients with ventricular arrhythmias: a cardiac magnetic resonance and 18F-FDG cardiac PET study

Cardiac sarcoidosis (CS) is known to be associated with ventricular tachycardia (VT); however, most investigations to date have focused on patients with known extra-cardiac sarcoidosis. The presence of CS is typically evaluated using 18F-fluorodeoxyglucose (18F-FDG) uptake on cardiac positron emission tomography (PET) or late gadolinium enhancement (LGE) on cardiac magnetic resonance (CMR). In this study, we sought to determine the prevalence of primary CS and the relationship between myocardial 18F-FDG uptake and LGE in patients with VT without known sarcoidosis. We retrospectively identified 67 patients without known sarcoidosis or active ischemic heart disease (i.e. significant ischemic disease that had not been previously revascularized) referred for both CMR and PET for evaluation of VT. Standard cine- and LGE- CMR and cardiac PET protocols were used. Myocardial LGE was defined as signal intensity > 5 SDs above the mean signal intensity of normal myocardium. Cardiac PET images were considered positive if there was focal myocardial 18F-FDG uptake having greater activity than the left ventricular blood pool. 45 patients (67%) had LGE, while only 4 (6%) had myocardial FDG uptake. Nine percent of patients with LGE had FDG-uptake while none without LGE did, and 10% of the cohort had indeterminate FDG uptake presumably from poor dietary preparation. Of those with both FDG uptake and LGE, 3/4 ultimately received a clinical diagnosis of CS. 4.5% of patients without previously known sarcoidosis or active ischemic heart disease presenting with VT have newly diagnosed CS. Detection of CS can be increased using a CMR first approach followed by cardiac PET for patients with non-ischemic LGE.

18F-fluorodeoxyglucose positron emission tomography/computed tomography in the evaluation of spinal giant cell tumors

OBJECTIVE

To investigate the value of ¹⁸F-fluorodeoxyglucose (¹⁸F-FDG) positron emission tomography/computed tomography (PET/CT) in the evaluation of spinal giant cell tumors (GCTs).

MATERIALS AND METHODS

The PET/CT and clinical data of 16 patients with spinal GCTs were reviewed. The maximal standardized uptake value (SUVmax), longest diameter, and CT features of spinal GCTs were analyzed. The value of PET/CT and MRI in displaying the recurrent lesions was compared. PET Response Criteria in Solid Tumors were adopted to evaluate the response to radiotherapy.

RESULTS

Data from 7 males and 9 females (median age 32.5 years) were analyzed. Eight patients had primary GCTs with a median SUVmax of 11.91 and a median length of 4.42 cm. Eight patients had relapsed GCTs with a median SUVmax of 10.34 and a median length of 6.23 cm. There was no statistical difference between the SUVmax of primary and relapsed GCTs. The SUVmax did not correlate with length. In 8 relapsed patients, 4 lesions invaded the vertebral canal, but 2 of which were not displayed on MRI. Metal prostheses showed extremely low signal intensity on MRI, even in the 3 cases with increased intra-prosthetic ¹⁸F-FDG concentration. Five relapsed patients with subsequent radiotherapy had a repeat PET/CT. A complete, partial, and stable metabolic response was observed in 1, 3, and 1 patient, respectively.

CONCLUSIONS

Both the primary and recurrent spinal GCTs avidly accumulate ¹⁸F-FDG. For recurrent GCTs, PET/CT may provide incremental value in the assessment of the vertebral canal and intra-prosthetic involvement and the response to radiotherapy.

The Prognostic Role of Baseline Metabolic Tumor Burden and Systemic Inflammation Biomarkers in Metastatic Castration-Resistant Prostate Cancer Patients Treated with Radium-223: A Proof of Concept Study

Over the last years has emerged the urgent need for the identification of reliable prognostic biomarkers able to potentially identify metastatic castration-resistant prostate cancer (mCRPC) patients most likely to benefit from Radium-223 (Ra-223) since baseline. In the present monocentric retrospective study, we analyzed the prognostic power of systemic inflammation biomarkers and 18F-Fluorodeoxyglucose Positron Emission Tomography/Computed Tomography (FDG-PET)-derived parameters and their potential interplay in this clinical setting. The following baseline laboratory parameters were collected in 59 mCRPC patients treated with Ra-223: neutrophil-to-lymphocyte ratio (NLR), derived NLR (dNLR), lymphocyte-to-monocyte ratio (LMR), platelets-to-lymphocyte ratio (PLR), and systemic inflammation index (SII), while maximum Standardized Uptake Value, Metabolic Tumor Volume (MTV), and Total Lesion Glycolysis (TLG) were calculated in the 48 of them submitted to baseline FDG-PET. At the univariate analysis, NLR, dNLR, MTV, and TLG were able to predict the overall survival (OS). However, only NLR and MTV were independent predictors of OS at the multivariate analysis. Additionally, the occurrence of both increased NLR and MTV at baseline identified mCRPC patients at higher risk for lower long-term survival after treatment with Ra-223. In conclusion, the degree of systemic inflammation, the quantification of the metabolically active tumor burden and their combination might represent potentially valuable tools for identifying mCRPC patients who are most likely to benefit from Ra-223. However, further studies are needed to reproduce these findings in larger settings.

Impairment of Everyday Spatial Navigation Abilities in Mild Cognitive Impairment Is Weakly Associated with Reduced Grey Matter Volume in the Medial Part of the Entorhinal Cortex

BACKGROUND

Research in rodents identified specific neuron populations encoding information for spatial navigation with particularly high density in the medial part of the entorhinal cortex (ERC), which may be homologous with Brodmann area 34 (BA34) in the human brain.

OBJECTIVE

The aim of this study was to test whether impaired spatial navigation frequently occurring in mild cognitive impairment (MCI) is specifically associated with neurodegeneration in BA34.

METHODS

The study included baseline data of MCI patients enrolled in the Alzheimer's Disease Neuroimaging Initiative with high-resolution structural MRI, brain FDG PET, and complete visuospatial ability scores of the Everyday Cognition test (VS-ECog) within 30 days of PET. A standard mask of BA34 predefined in MNI space was mapped to individual native space to determine grey matter volume and metabolic activity in BA34 on MRI and on (partial volume corrected) FDG PET, respectively. The association of the VS-ECog sum score with grey matter volume and metabolic activity in BA34, APOE4 carrier status, age, education, and global cognition (ADAS-cog-13 score) was tested by linear regression. BA28, which constitutes the lateral part of the ERC, was used as control region.

RESULTS

The eligibility criteria led to inclusion of 379 MCI subjects. The VS-ECog sum score was negatively correlated with grey matter volume in BA34 (β= -0.229, p = 0.022) and age (β= -0.124, p = 0.036), and was positively correlated with ADAS-cog-13 (β= 0.175, p = 0.003). None of the other predictor variables contributed significantly.

CONCLUSION

Impairment of spatial navigation in MCI is weakly associated with BA34 atrophy.

Malignant perivascular epithelioid cell tumor of the ileum on 18F-fluorodeoxyglucose positron emission tomography/ computed tomography with pathological correlation

A 75-year-old woman presented with a 1-month history of abdominal pain. Contrast-enhanced computed tomography (CT) demonstrated a large solid mass in the left lower abdominal quadrant, suspicious for malignancy. Staging with ¹⁸F-fluorodeoxyglucose (FDG) positron emission tomography/CT imaging demonstrated intense FDG uptake in the mass with no evidence of metastatic disease. Complete surgical resection was performed, and histopathological analysis confirmed a malignant perivascular epithelioid cell tumor of the ileum.

Performance of 18F-FDG PET/CT Radiomics for Predicting EGFR Mutation Status in Patients With Non-Small Cell Lung Cancer

Objective

To assess the performance of pretreatment ¹⁸F-fluorodeoxyglucose positron emission tomography/computed tomography (¹⁸F-FDG PET/CT) radiomics features for predicting EGFR mutation status in patients with non-small cell lung cancer (NSCLC).

Patients and Methods

We enrolled total 173 patients with histologically proven NSCLC who underwent preoperative ¹⁸F-FDG PET/CT. Tumor tissues of all patients were tested for EGFR mutation status. A PET/CT radiomics prediction model was established through multi-step feature selection. The predictive performances of radiomics model, clinical features and conventional PET-derived semi-quantitative parameters were compared using receiver operating curves (ROCs) analysis.

Results

Four CT and two PET radiomics features were finally selected to build the PET/CT radiomics model. Compared with area under the ROC curve (AUC) equal to 0.664, 0.683 and 0.662 for clinical features, maximum standardized uptake values (SUV_max) and total lesion glycolysis (TLG), the PET/CT radiomics model showed better performance to discriminate between EGFR positive and negative mutations with the AUC of 0.769 and the accuracy of 67.06% after 10-fold cross-validation. The combined model, based on the PET/CT radiomics and clinical feature (gender) further improved the AUC to 0.827 and the accuracy to 75.29%. Only one PET radiomics feature demonstrated significant but low predictive ability (AUC = 0.661) for differentiating 19 Del from 21 L858R mutation subtypes.

Conclusions

EGFR mutations status in patients with NSCLC could be well predicted by the combined model based on ¹⁸F-FDG PET/CT radiomics and clinical feature, providing an alternative useful method for the selection of targeted therapy.

Detection of muscle metastases on 18F-fluorodeoxyglucose positron emission tomography/computed tomography scan in 13 cases

Muscular metastases (MMs) form an infrequent entity, and their physiopathology is still not well-defined. In this study, we estimated the incidence of MMs that were detected by ¹⁸F-fluorodeoxyglucose positron emission tomography/computed tomography and also specified their metabolic characteristics. This study includes 13 patients with MMs from a remotely located primary tumor. The results of this study showed an incidence of MMs at about 1%, with the most frequently involved muscles being iliopsoas and paraspinal. Lung cancer seems to be the most common tumor that causes MMs. Furthermore, these MMs vary in size and physiological uptake; they seem to be out of the ordinary and easily detected. They are often associated with other extra muscular locations and frequently involve the trunk muscles. Their detection in the course of the evolution of a specific neoplasia testifies to their aggressiveness and portends an unfavorable prognosis. The data in our series confirm that in the literature regarding the underlying primary tumors and anatomical sites involved by MMs.

Association between non-alcoholic fatty liver disease and myocardial glucose uptake measured by 18F-fluorodeoxyglucose positron emission tomography

BACKGROUND

Non-alcoholic fatty liver disease (NAFLD) has emerged as an independent risk factor for cardiovascular diseases. However, there were few studies evaluating the condition of myocardial glucose metabolism in patients with NAFLD. Therefore, the aim of this study was to investigate the association between NAFLD and myocardial glucose uptake assessed by using 18F-fluorodeoxyglucose (18F-FDG) positron emission tomography (PET) and whether or not alteration of myocardial glucose uptake could be an indicator linking to cardiac dysfunction in NAFLD individuals.

METHODS AND RESULTS

A total of 743 asymptomatic subjects (201 with NAFLD, 542 without NAFLD) were retrospectively studied. The ratio of maximum myocardium FDG uptake to the mean standardized uptake value of liver (SUVratio) was calculated to estimate myocardial glucose uptake by using 18F-FDG PET. The diagnosis of fatty liver and fatty liver grading was confirmed by unenhanced CT according to diagnostic criterion of previous studies. The myocardial geometric and functional data were obtained by echocardiogram. Myocardial glucose uptake was significantly lower in individuals with NAFLD compared with those without fatty liver (P < .001). When analysis of association trend was performed, SUVratio quartiles showed correlated inversely and strongly with liver steatosis (P < .001). NAFLD patients with lower myocardial glucose uptake were more likely to have higher proportion of increased LV filling pressure (P < .05). A significant relationship between myocardial SUVratio and E/e' ratio was presented in the trend analysis (P < .05). Moreover, multivariate regression analysis showed that myocardial glucose uptake was independently associated with NAFLD after adjusting for clinical important factors (all P < .001).

CONCLUSIONS

The presence of NAFLD in otherwise healthy subjects is closely associated with decreased myocardial glucose uptake assessing by 18F-FDG PET imaging. Furthermore, the NAFLD individuals with lower myocardial glucose uptake are more likely to have high risk of having impaired diastolic heart function.

A Rare Case of Pulmonary Schistosomiasis: 18F-Fluorodeoxyglucose Positron Emission Tomography/Computed Tomography Findings

Schistosomiasis is a helminthic infection acquired through direct contact with contaminated fresh water. To the best of our knowledge, this is the first case pulmonary of schistosomias is evaluated with 18F-fluorodeoxyglucose (18F-FDG) positron emission tomography/computed tomography (PET/CT) reported in the literature. Functional imaging with 18F-FDG PET/CT may help in the diagnosis of schistosomiasis, leading to a correct definition of the disease extension.

Predictive Value of 18F-Fluorodeoxyglucose Positron Emission Tomography or Positron Emission Tomography/Computed Tomography for Assessment of Occult Lymph Node Metastasis in Non-Small Cell Lung Cancer

OBJECTIVE

The purpose of the current study was to investigate the diagnostic performance of 18F fluorodeoxyglucose (FDG) positron emission tomography (PET) or positron emission tomography/computed tomography (PET/CT) for the prediction of occult lymph node metastasis (OLNM) in non-small cell lung cancer (NSCLC) patients through a systematic review and meta-analysis.

METHODS

The PubMed, Cochrane, and EMBASE database, from the earliest available date of indexing through March 31, 2020, were searched for studies evaluating the diagnostic performance of preoperative 18F FDG PET or PET/CT for the prediction of OLNM in NSCLC patients.

RESULTS

Across 14 studies (3,535 patients), the pooled sensitivity for 18F FDG PET or PET/CT was 0.79 (95% CI; 0.70-0.86) with heterogeneity (I2 = 81.5, p < 0.001) and a pooled specificity of 0.65 (95% CI; 0.57-0.72) with heterogeneity (I2 = 93.7, p < 0.001). Likelihood ratio (LR) syntheses gave an overall positive likelihood ratio (LR+) of 2.3 (95% CI; 1.9-2.6) and a negative likelihood ratio (LR-) of 0.32 (95% CI; 0.23-0.44). The pooled diagnostic odds ratio (DOR) was 7 (95% CI; 5-10). The hierarchical summary receiver operating characteristic curve indicates that the area under the curve was 0.77 (95% CI; 0.74-0.81).

CONCLUSION

The current meta-analysis showed a moderate sensitivity and specificity of 18F FDG PET or PET/CT for the prediction of OLNM in NSCLC patients. The DOR was low and the likelihood ratio scatter-gram indicated that 18F FDG PET or PET/CT might not be useful for the prediction of OLNM in NSCLC patients and not for its exclusion.

Hot-clot artifact in the lung parenchyma on 18F-fluorodeoxyglucose positron emission tomography/computed tomography mimicking malignancy with a homolateral non-small cell lung cancer

¹⁸F-fluorodeoxyglucose (¹⁸F-FDG) positron emission tomography/computed tomography (CT) is an important tool widely used in the oncology to stage and restage various malignancies. Intense focal FDG uptake in the lung parenchyma associated with the absence of anatomical lesion detected on CT can be explained by a lung microembolism, known as hot-clot artifact. We report, to the best of our knowledge, the first case describing a single hot-clot artifact located in the same lung as a histologically proven non-small cell lung cancer.

Distribution Characteristics of Colorectal Peritoneal Carcinomatosis Based on the Positron Emission Tomography/Peritoneal Cancer Index

Background: Colorectal peritoneal carcinomatosis (CRPC) is a primary cause of death in colorectal cancer (CRC) patients. In the past, computed tomography (CT) has been the primary method used to evaluate the distribution of CRPC. This study uses ¹⁸F-FDG positron emission tomography/computed tomography (PET/CT) to investigate the distribution characteristics of CRPC. Materials and Methods: The distribution characteristics of 46 patients with CRC who were treated in the authors' hospital were retrospectively analyzed using the peritoneal cancer index (PCI). Results: The 46 patients in the study showed CRPC involvement in 203 of the 598 abdominal and pelvic regions studied (33.9%, 203/598). The regional proportions of CRPC involvement, from high to low, were as follows: region 6 (13.8%), region 0 (10.3%), region 1 (9.9%), region 5 (8.9%), region 7 (8.4%), region 3 (8.4%), region 2 (7.4%), region 4 (7.4%), region 11 (6.9%), region 8 (6.4%), region 12 (5.4%), region 9 (3.4%), and region 10 (3.4%). Thirty-three patients had a PCI of <20, and 13 patients had a PCI of ≥20. Those 13 were among the 17 (37% 17/46) who had CRPC involvement in all three regions. According to the location of the primary CRC focus, the 46 patients were divided into three groups: right hemicolon, left hemicolon, and rectum. The frequency of CRPC was greater in the rectum group than in the left hemicolon group, and the SUV_max of CRPC was greater in the right hemicolon group than in the left hemicolon group; these differences were statistically significant (p < 0.05). Conclusions: The distribution of CRPC has certain characteristics in the abdominal and pelvic cavities. The PET-PCI scores can provide a basis for the diagnosis and clinical treatment strategies in patients with CRC.

Primary hepatic diffuse large B-cell lymphoma presenting unusual imaging features

Primary hepatic lymphomas are frequently misdiagnosed, due to their rarity and non-specific clinical manifestations. As these tumors can be successfully treated with chemotherapy and/or radiotherapy, early recognition on imaging is essential to avoid unnecessary surgery. We report a case of primary hepatic lymphoma in a 73-year-old woman presenting with a 1-week history of persistent fever and elevated hepatobiliary enzymes. Ultrasound showed a hypoechoic hepatic mass in the anterior segment. Dynamic contrast-enhanced computed tomography (CT) revealed an ill-defined solitary mass showing peripherally dominant slight-to-moderate enhancement contrasting with a hypovascular central area. On magnetic resonance imaging, the mass showed moderate hyperintensity on T2-weighted imaging, hypointensity on T1-weighted imaging, doughnut-like hyperintensity on diffusion-weighted imaging, and an obviously low apparent diffusion coefficient (ADC). The pattern of enhancement resembled that of CT. Neither calcification nor any fat component was observed. Doughnut-like accumulation was seen on ¹⁸F-fluorodeoxyglucose (FDG)-positron emission tomography/CT without other FDG-avid lesions. Imaging findings suggested the possibility of cholangiocellular carcinoma, but the low ADC and extremely high FDG accumulation were suggestive of malignant lymphoma, and diffuse large B-cell lymphoma was pathologically confirmed from percutaneous biopsy. The mass disappeared after radiochemotherapy, and no recurrence has been observed for 3 years.

PD-L1 in Lung Adenocarcinoma: Insights into the Role of 18F-FDG PET/CT

Purpose

This study aimed to evaluate the role of ¹⁸F-fluorodeoxyglucose (¹⁸F-FDG) positron emission tomography (PET)/computed tomography (CT) in expression of tumor programmed death ligand-1 (PD-L1) expression and prognostic significance of ¹⁸F-FDG PET/CT at different PD-L1 status in patients with lung adenocarcinoma.

Patients and Methods

Seventy-three patients with primary lung adenocarcinoma who received ¹⁸F-FDG PET/CT before treatment were retrospectively included in this study. Expression of tumor PD-L1, programmed death-1 (PD-1) and glucose metabolic parameters were evaluated.

Results

Tumor PD-L1 expression was positively correlated with maximum standardized uptake value (SUVmax), total lesion glycolysis (TLG), hexokinase II (HK-II) and glucose transporter 1 (GLUT-1) (P<0.0001 for all). SUVmax was a unique independent predictor of tumor PD-L1 expression, with an optimal cut-off value of 9.5. For all the patients, tumor stage (P<0.001) and SUVmax (P=0.009) were independent prognostic indicators of disease-free survival (DFS)/progression-free survival (PFS) while carcino-embryonic antigen (CEA) (P=0.003), Ki67 (P=0.042), PD-L1 (P=0.048) and TLG (P=0.004) were independent prognostic indicators of overall survival (OS). Tumor stage (P=0.004) and SUVmax (P=0.022) were independent prognostic indicators of DFS/PFS while TLG (P=0.012) and CEA (P=0.045) were independent prognostic indicators of OS in the PD-L1-positive group. In the PD-L1-negative group, tumor stage (P=0.002) and CEA (P=0.006) were unique independent prognostic indicators of DFS/PFS and OS, respectively.

Conclusion

¹⁸F-FDG PET/CT may potentially predict tumor PD-L1 expression and play a role in predicting prognosis of PD-L1/PD-1 immunotherapy in lung adenocarcinoma.

Benign uptake of 18F-fluorodeoxyglucose in the gallbladder on positron emission tomography-computed tomography

¹⁸F-fluorodeoxyglucose (FDG) positron emission tomography (PET) has been established as the indisputable tool in the oncological arena to diagnose, stage/restage, and report treatment response for various tumor malignancies. FDG uptake mostly identifies pathological uptake in oncological scans with the tracer on PET studies; however, benign uptakes are also commonly seen. Reported here is a benign case of increased uptake of the FDG on a PET with computed tomography scan in the gallbladder (GB) of a patient being screened for a known carcinoma breast. The benign accumulation of the tracer is seen in the GB to various degrees and this phenomenon may occur as a result of FDG excretion into the bile. When interpreting clinical PET images, recognition of this phenomenon is important to avoid misdiagnosing physiological GB FDG uptake as pathological so as to avoid misinterpretations of the findings.

Quantitative Comparison of Prone and Supine PERCIST Measurements in Breast Cancer

Positron emission tomography (PET) is typically performed in the supine position. However, breast magnetic resonance imaging (MRI) is performed in prone, as this improves visibility of deep breast tissues. With the emergence of hybrid scanners that integrate molecular information from PET and functional information from MRI, it is of great interest to determine if the prognostic utility of prone PET is equivalent to supine. We compared PERCIST (PET Response Criteria in Solid Tumors) measurements between prone and supine FDG-PET in patients with breast cancer and the effect of orientation on predicting pathologic complete response (pCR). In total, 47 patients were enrolled and received up to 6 cycles of neoadjuvant therapy. Prone and supine FDG-PET were performed at baseline (t₀; n = 46), after cycle 1 (t₁; n = 1) or 2 (t₂; n = 10), or after all neoadjuvant therapy (t₃; n = 19). FDG uptake was quantified by maximum and peak standardized uptake value (SUV) with and without normalization to lean body mass; that is, SUV_max, SUV_peak, SUL_max, and SUL_peak. PERCIST measurements were performed for each paired baseline and post-treatment scan. Receiver operating characteristic analysis for the prediction of pCR was performed using logistic regression that included age and tumor size as covariates. SUV and SUL metrics were significantly different between orientation (P < .001), but were highly correlated (P > .98). Importantly, no differences were observed with the PERCIST measurements (P > .6). Overlapping 95% confidence intervals for the receiver operating characteristic analysis suggested no difference at predicting pCR. Therefore, prone and supine PERCIST in this data set were not statistically different.

A 1-week extension of a ketogenic diet provides a further decrease in myocardial 18F-FDG uptake and a high detectability of myocarditis with FDG-PET

BACKGROUND

Short periods of fasting and/or low-carbohydrate diet have been proven beneficial for decreasing the myocardial uptake of 18F-fluorodeoxyglucose (18F-FDG) and enhancing the detection of inflammatory heart diseases by 18F-FDG positron emission tomography (PET). This study aimed at determining whether this benefit is increased when a low-carbohydrate ketogenic diet is prolonged up to 7 days.

METHODS

Wistar rats underwent serial 18F-FDG-PET imaging after an 18-hour fasting period and after 2, 4 and 7 days of a ketogenic diet (3% carbohydrate) and they were compared to rats submitted to the same protocol but with normal diet (44% carbohydrate). The 18F-FDG-PET/ketogenic protocol was also applied in rats with immune myocarditis (injection of porcine cardiac myosin).

RESULTS

The 7-day ketogenic diet was associated with (1) a sustained increase in circulating ketone bodies at an equivalent level to that reached after 18-hour fasting, (2) a gradual decrease in 18F-FDG uptake within normal myocardium reaching a lower level compared to fasting at the 7th day (myocardium-to-blood ratios: 1.68 ± 1.02 vs 3.25 ± 1.40, P < .05) and (3) a high 18F-FDG-PET detectability of myocarditis areas.

CONCLUSION

One-week extension of a ketogenic diet provides a further decrease in the 18F-FDG uptake of normal myocardium and a high detectability of inflammatory areas.

Unexpected rare metastases of renal cell carcinoma

Renal cell carcinomas (RCCs) commonly metastasize to the lungs and bones and rarely to the parathyroid, maxillary sinus, and adrenals. It is indeed very rare to have these all these metastases occurring simultaneously in an individual. We share a case of 67-year-old woman provisionally treated for parathyroid carcinoma but subsequently found to actually have metastatic RCC to the left maxillary sinus, parathyroid, lungs, and adrenals on ¹⁸F-fluorodeoxyglucose positron emission tomography-computed tomography.

Quantification of 18F-fluorodeoxyglucose uptake to detect residual nodal disease in locally advanced head and neck squamous cell carcinoma after chemoradiotherapy: results from the ECLYPS study

BACKGROUND

The Hopkins criteria were introduced for nodal response evaluation after therapy in head and neck cancer, but its superiority over quantification is not yet confirmed.

METHODS

SUV_{body weight} thresholds and lesion-to-background ratios were explored in a prospective multicenter study of standardized FDG-PET/CT 12 weeks after CRT in newly diagnosed locally advanced head and neck squamous cell carcinoma (LAHNSCC) patients (ECLYPS). Reference standard was histology, negative FDG-PET/CT at 12 months after treatment or ≥ 2 years of negative follow-up. Area under the receiver operator characteristics curves (AUROC) were estimated and obtained thresholds were validated in an independent cohort of HNSCC patients (n = 127).

RESULTS

In ECLYPS, 124 patients were available for quantification. With a median follow-up of 20.4 months, 23 (18.5%) nodal neck recurrences were observed. A SUV₇₀ threshold of 2.2 (AUROC = 0.89; sensitivity = 79.7%; specificity = 80.8%) was identified as optimal metric to identify nodal recurrence within 1 year after therapy. For lesion-to-background ratios, an SUV₅₀/SUV_liver threshold of 0.96 (AUROC = 0.89; sensitivity = 79.7%; specificity = 82.8%) had the best performance. Compared with Hopkins criteria (AUROC = 0.81), SUV₇₀ and SUV₅₀/SUV_liver provided a borderline significant (p = 0.040 and p = 0.094, respectively) improvement. Validation of thresholds yielded similar AUROC values (SUV₇₀ = 0.93, SUV₅₀/SUV_liver = 0.95), and were comparable to the Hopkins score (AUROC = 0.91; not statistically significant).

CONCLUSION

FDG quantification detects nodal relapse in LAHNSCC patients. When using EARL standardized PET acquisitions and reconstruction, absolute SUV metrics (SUV₇₀ threshold 2.2) prove robust, yet ratios (SUV₅₀/SUV_liver, threshold 0.96) may be more useful in routine clinical care. In this setting, the diagnostic value of quantification is comparable to the Hopkins criteria.

TRIAL REGISTRATION

US National Library for Medicine, NCT01179360. Registered 11 August 2010, https://clinicaltrials.gov/ct2/show/NCT01179360.

The impact of 18F-FDG PET on initial staging and therapy planning of pediatric soft-tissue sarcoma patients

BACKGROUND

Soft-tissue sarcomas in children are a histologically heterogenous group of malignant tumors accounting for approximately 7% of childhood cancers. There is a paucity of data on the value of ¹⁸F-fluorodeoxyglucose (FDG) positron emission tomography (PET)/computed tomography (CT) for initial staging and whether PET influenced management of these patients.

OBJECTIVE

The aim of this analysis is to assess the use of ¹⁸F-FDG PET exclusively, and as a supplement to cross-sectional imaging in comparison to typical imaging protocols (CT and magnetic resonance imaging [MRI]) for initial staging as well as therapy planning in pediatric soft-tissue sarcoma patients.

MATERIALS AND METHODS

The list of ¹⁸F-FDG PET/CT performed for soft-tissue sarcoma between March 2007 and October 2017 was obtained from the Hospital Information System database. Twenty-six patients who had received ¹⁸F-FDG PET, MRI and/or CT at initial diagnosis were included in the study. ¹⁸F-FDG PET and concurrent diagnostic CT and MRI at initial staging were independently reviewed to note the number of primary and metastatic lesions detected by each modality. A chart review was conducted to collect information on final diagnosis, staging and treatment plan.

RESULTS

During the study period, 26 patients (15 females) ages 1.3-17.9 years (median age: 6 years) had received ¹⁸F-FDG PET/CT at initial diagnosis of soft-tissue sarcoma. Diagnostic CT was available for comparison in all 26 patients and MRI was available in 18 patients. The mean interval between cross-sectional imaging and ¹⁸F-FDG PET was 5.9 days (range: 0-30 days). All 26 primary lesions were equally detected by ¹⁸F-FDG PET compared to CT and MRI. From 84 metastatic lesions, 16 were detected by PET as well as CT and MRI, 12 by ¹⁸F-FDG PET only (included mainly lymph node metastases) and 56 by CT and MRI only (included mainly lung metastases). ¹⁸F-FDG PET changed therapy planning in 5 patients out of 26 (19%) by showing additional lesions not detected by CT and MRI.

CONCLUSION

¹⁸F-FDG PET proved to be a valuable tool for precise initial staging of pediatric soft-tissue sarcoma patients, especially in detecting lymph node metastasis, and could be included in their initial work-up. Given the relative rarity and heterogeneity of this group of tumors, additional investigations are required to definitely establish a role for ¹⁸F-FDG PET in the initial staging and therapy planning of soft-tissue sarcoma in the pediatric population.

A Metabolic Intravascular Platform to Study FDG Uptake in Vascular Injury

PURPOSE

Metabolic alterations underlie many pathophysiological conditions, and their understanding is critical for the development of novel therapies. Although the assessment of metabolic changes in vivo has been historically challenging, recent developments in molecular imaging have allowed us to study novel metabolic research concepts directly in the living subject, bringing us closer to patients. However, in many instances, there is need for sensors that are in close proximity to the organ under investigation, for example to study vascular metabolism.

METHODS

In this study, we developed and validated a metabolic detection platform directly in the living subject under an inflammatory condition. The signal collected by a scintillating fiber is amplified using a photomultiplier tube and decodified by an in-house tunable analysis platform. For in vivo testing, we based our experiments on the metabolic characteristics of macrophages, cells closely linked to inflammation and avid for glucose and its analog ¹⁸F-fluorodeoxyglucose (¹⁸F-FDG). The sensor was validated in New Zealand rabbits, in which inflammation was induced by either a) high cholesterol (HC) diet for 16 weeks or b) vascular balloon endothelial denudation followed by HC diet.

RESULTS

There was no difference in weight, hemodynamics, blood pressure, or heart rate between the groups. Vascular inflammation was detected by the metabolic sensor (Inflammation: 0.60 ± 0.03 AU vs. control: 0.48 ± 0.03 AU, p = 0.01), even though no significant inflammation/atherosclerosis was detected by intravascular ultrasound, underscoring the high sensitivity of the system. These findings were confirmed by the presence of macrophages on ex vivo aortic tissue staining.

CONCLUSION

In this study, we validated a tunable very sensitive metabolic sensor platform that can be used for the detection of vascular metabolism, such as inflammation. This sensor can be used not only for the detection of macrophage activity but, with alternative probes, it could allow the detection of other pathophysiological processes.