A case of infantile spasms with three possibly pathogenic de novo missense variants in NF1 and GABBR1.

Neurofibromatosis type 1 (NF1) is one of the most common hereditary neurocutaneous disorders. Here, we report a unique case of a patient with typical NF1 findings and infantile spasms who had three possibly pathogenic de novo variants, c.3586C>T, p.(Leu1196Phe) and c.3590C>T, p.(Ala1197Val) in NF1 located in cis and c.1042G>C, p.(Ala348Pro) in GABBR1. This study contributes to our understanding of the effect of two cis variants on NF1 phenotypes and GABBR1-related neuropsychiatric disorders.

[18F]FDG uptake in axillary lymph nodes and deltoid muscle after COVID-19 mRNA vaccination: a cohort study to determine incidence and contributing factors using a multivariate analysis.

PURPOSE: Reactive FDG uptake in the axillary lymph nodes (ALN) and deltoid muscle (DM) after COVID-19 mRNA vaccination has been recognized, although the actual situation in the Japanese population remains unknown. To determine the incidence of reactive FDG uptake and its contributing factors, we retrospectively studied a cohort of subjects who were vaccinated at our hospital. METHODS: Whole-body FDG-PET/CT examinations performed in 237 subjects out of 240 subjects with a definite history of COVID-19 vaccination (BNT162b2; BioNTech-Pfizer) were analyzed. Positivity and SUVmax of FDG uptake in the ALN and DM ipsilateral to vaccination, various subject characteristics, and the grade of the pathological FDG-PET/CT findings were evaluated using a multivariate analysis. RESULTS: FDG uptake in the ALN and DM ipsilateral to vaccination was seen in about 60% of the subjects even soon (0-4 days) after the first vaccination, with percentages reaching 87.5% and 75.0%, respectively, after the second vaccination. DM uptake had almost disappeared at around 2 weeks, while ALN uptake persisted for 3 weeks or longer. A multivariate analysis showed that a short duration since vaccination, a younger age, a female sex, and a low FDG-PET/CT grade (minimal pathological FDG uptake) contributed significantly to positive ALN uptake, while a short duration since vaccination and a female sex were the only significant contributors to positive DM uptake. This study is the first to identify factors contributing to positive FDG uptake in ALN and DM after COVID-19 vaccination. CONCLUSION: A high incidence of FDG uptake in ALN and DM was observed after vaccination. ALN uptake seemed to be associated with a younger age, a female sex, and minimal pathological FDG uptake. After vaccination, an acute inflammatory reaction in DM followed by immune reaction in ALN linked to humoral immunity may be speculated.

Advanced Diagnostic System and Introduction of Newborn Screening of Adrenoleukodystrophy and Peroxisomal Disorders in Japan.

We established a diagnostic system for adrenoleukodystrophy (ALD) and peroxisomal disorders (PD) over 35 years ago in Japan, and have diagnosed 237 families with ALD and more than 100 cases of PD other than ALD using biochemical and molecular analyses. In particular, since the only treatment for the cerebral form of ALD is hematopoietic stem cell transplantation at an early stage of onset, we have developed a protocol for the rapid diagnosis of ALD that can provide the measurements of the levels of very-long-chain fatty acids in the serum and genetic analysis within a few days. In addition, to improve the prognosis of patients with ALD, we are working on the detection of pre-symptomatic patients by familial analysis from the proband, and the introduction of newborn screening. In this review, we introduce the diagnostic and newborn screening approaches for ALD and PD in Japan.

Determining the extent of tumor resection at surgical planning with 18F-fluciclovine PET/CT in patients with suspected glioma: multicenter phase III trials.

OBJECTIVE: Glioma is the most common type of central nervous system tumor reported worldwide. Current imaging technologies have limitations in the diagnosis and assessment of glioma. The present study aimed to confirm the diagnostic efficacy and safety of anti-1-amino-3-[18F]fluorocyclobutane carboxylic acid (18F-fluciclovine; anti-[18F]FACBC) as a radiotracer for patients undergoing combined positron emission tomography and computed tomography (PET/CT) for suspected glioma. METHODS: Combined data from two multicenter, open-label phase III clinical trials were evaluated for this study. The two trials enrolled patients with suspected high- or low-grade glioma on the basis of clinical symptoms, clinical course, and magnetic resonance imaging findings, and who were scheduled for tumor resection surgery. Patients fasted for ≥ 4 h and received 2 mL of 18F-fluciclovine (radioactivity dose 78.3-297.0 MBq), followed by a 10-min PET scan 10-50 min after injection. The primary efficacy endpoint was the positive predictive value (PPV) of the gadolinium contrast-enhanced T1-weighted image negative [Gd (-)] and 18F-fluciclovine PET-positive [PET ( +)] area of the scans, using the histopathological diagnosis of the tissue sampled from that area as the standard of truth. All adverse events reported during the study were recorded for safety analysis. RESULTS: A total of 45 patients aged 23-89 years underwent 18F-fluciclovine PET; 31/45 patients (68.9%) were male, and 30/45 patients (66.7%) were suspected to have high-grade glioma. The PPV of 18F-fluciclovine PET in the Gd (-) PET ( +) area was 88.0% (22/25 areas, 95% confidence interval: 70.0-95.8). The extent of planned tumor resection was modified in 47.2% (17/36 cases) after 18F-fluciclovine PET scan, with an extension of area in 30.6% (11/36 cases) and reduction in 16.7% (6/36 cases). Furthermore, tissue samples collected from PET ( +) areas tended to have a higher malignancy grade compared with those from PET (-) areas. Overall, 18F-fluciclovine was well tolerated. CONCLUSION: 18F-fluciclovine PET/CT is useful for determining the extent of tumor resection at surgical planning, and may serve as a safe and effective diagnostic tool for patients with suspected glioma. TRIAL REGISTRATION: These trials were registered in the Japan Pharmaceutical Information Center Clinical Trials Information (JapicCTI-152986, JapicCTI-152985).

Acute encephalopathy in children with tuberous sclerosis complex.

OBJECTIVE: We examined the clinical manifestations of acute encephalopathy (AE) and identify risk factors for AE in children with tuberous sclerosis complex (TSC). METHODS: The clinical data of 11 children with clinically diagnosed TSC associated with AE and 109 children with clinically diagnosed TSC alone aged 4 years or older were collected from 13 hospitals. RESULTS: Of the 11 children with AE, 5 had histories of febrile seizures (FS), and all had histories of febrile status epilepticus (FSE). AE developed within 24 h after fever onset in all children with seizures lasting 30 min or longer. All children developed coma after seizure cessation. Head magnetic resonance imaging (MRI) revealed widespread abnormalities in the cerebral cortex, subcortical white matter, corpus callosum, basal ganglia, and thalamus. One child died; seven had severe neurological sequelae; and the other three, mild sequelae. Logistic regression analysis revealed that a history of FSE was correlated with the development of AE. SIGNIFICANCE: AE in children with TSC was characterized by sudden onset after fever, followed by coma, widespread brain edema evident on MRI, and poor outcomes. A history of FSE was a risk factor for the development of AE.

Comparison of 18F-FDG PET/CT and 67Ga-SPECT for the diagnosis of fever of unknown origin: a multicenter prospective study in Japan.

OBJECTIVE: The aim of this multicenter prospective study was to compare the sensitivity of 18F-fluorodeoxyglucose (FDG)-positron emission tomography/computed tomography (PET/CT) with that of 67Ga single photon emission computed tomography (SPECT) for the identification of the site of greatest importance for the final diagnosis of the cause of fever of unknown origin (FUO). METHODS: The study participants consisted of patients with an axillary temperature ≥ 38.0 °C on ≥ 2 occasions within 1 week, with repeated episodes for ≥ 2 weeks prior to providing consent, and whose final diagnosis after undergoing specific examinations, including a chest-to-abdomen CT scan, was uncertain. All the patients underwent FDG-PET/CT imaging first, followed by 67Ga-SPECT imaging within 3 days. The results of the FDG-PET/CT and 67Ga-SPECT examinations were reviewed by the central image interpretation committee (CIIC), which was blinded to all other clinical information. The sensitivities of FDG-PET/CT and 67Ga-SPECT were then evaluated with regard to identifying the site of greatest importance for a final diagnosis of the cause of the fever as decided by the patient's attending physician. The clinical impacts (four grades) of FDG-PET/CT and 67Ga-SPECT on the final diagnosis were evaluated. RESULTS: A total of 149 subjects were enrolled in this study between October 2014 and September 2017. No adverse events were identified among the enrolled subjects. Twenty-one subjects were excluded from the study because of deviations from the study protocol. Among the 128 remaining subjects, a final diagnosis of the disease leading to the appearance of FUO was made for 92 (71.9%) subjects. The final diagnoses in these 92 cases were classified into four groups: noninfectious inflammatory disease (52 cases); infectious disease (31 cases), malignancy (six cases); and other (three cases). These 92 subjects were eligible for inclusion in the study's analysis, but one case did not meet the PET/CT image acquisition criteria; thus, PET/CT results were analyzed for 91 cases. According to the patient-based assessments, the sensitivity of FDG-PET/CT (45%, 95% CI 33.1-58.2%) was significantly higher than that for 67Ga-SPECT (25%, 95% CI 15.5-37.5%) (P = 0.0029). The clinical impact of FDG-PET/CT (91%) was also significantly higher than that for 67Ga-SPECT (57%, P < 0.001). CONCLUSIONS: FDG-PET/CT showed a superior sensitivity to 67Ga-SPECT for the identification of the site of greatest importance for the final diagnosis of the cause of FUO.

Clinical evaluation of childhood cerebral adrenoleukodystrophy with balint's symptoms.

BACKGROUND: Childhood cerebral adrenoleukodystrophy (CCALD) is the most common phenotype of adrenoleukodystrophy (ALD) and is characterized by the progression of intellectual, psychic, visual, and gait disturbances. Progression of this intractable disease can only be prevented by hematopoietic stem cell transplantation during the early stages of the disease. The aim of this study was to clinically evaluate children with CCALD who have visual symptoms to enable early diagnosis. METHODS: We enrolled 41 Japanese children with CCALD who had visual symptoms. We retrospectively analyzed age of onset, past medical history, initial symptoms, visual symptoms and findings on brain magnetic resonance imaging. RESULTS: The median age of disease onset was 7 years (range 5-10 years). The most common visual symptom was strabismus (n = 22). There was only one patient with the triad of symptoms of Balint's syndrome. Seventeen patients had incomplete Balint's syndrome and showed one or two of the triad of symptoms. Almost all patients with complete or incomplete Balint's syndrome showed bilateral parieto-occipital white matter lesions. CONCLUSIONS: CCALD could develop into Balint's syndrome, especially the incomplete form. Therefore, CCALD should be considered when boys show new symptoms, including lack of eye contact or bumping into objects.

A pediatric case of anaplastic astrocytoma with a gliomatosis cerebri; the growth pattern and changes in serum VEGF-121 levels after bevacizumab treatment.

Gliomatosis cerebri (GC) is a rare diffusely infiltrating glial neoplasm that carries a poor prognosis. Because tumors are undetectable in most patients at early-stage of the onset, a useful diagnostic method is expected. We compared serum vascular endothelial growth factor (VEGF)-121 levels in patients with GC or glioblastoma and controls. VEGF-121 levels were significantly higher in one patient with GC and patients with glioblastoma than in controls. VEGF-121 levels decreased in a patient with GC after bevacizumab-based therapy. Thus, VEGF-121 may be useful for diagnosing GC, its disease-monitoring and understanding its etiology.

Comparison of histopathology and preoperative 18F-FDG-PET/CT of osteomyelitis aiming for image guided surgery: A preliminary trial.

OBJECTIVE: There are currently no robust methods for accurately localizing the infection focus of osteomyelitis. Accumulation of fluorodeoxyglucose (FDG) is nonspecific, and it is well-known that it can indicate inflammatory cells and sites of inflammation, and its effectiveness in detecting osteomyelitis has been reported recently. However, the optimal cut-off value for the Standardized Uptake Value (SUV) in detecting the focus of osteomyelitis through 18F-FDG-PET/CT is not known. We investigated the optimal SUV cut-off values using 18F-FDG positron emission tomography (PET)computed tomography (CT) to visualize the infection focus of osteomyelitis accurately. PATIENTS AND METHODS: Initially, we investigated a case where osteomyelitis was bacteriologically detected after orthopedic surgery on lower limb. Based on the surgical pathology, we explored the optimal SUV cut-off value of the 18F-FDG PET/CT image taken before surgery. The SUV cut-off value was varied, using the GE Rainbow Color Scale on a dedicated workstation. We searched for the most accurate visualization of the extent of the infectious lesion. Subsequently, using the SUV cut-off value decided on the basis of the first case studied, we investigated the accuracy for diagnosing osteomyelitis. A total of sixteen patients underwent 18F-FDG PET/CT for suspected osteomyelitis (one case involved the upper extremity and 15 cases the lower one). All patients underwent surgery. The final diagnosis was made by means of bacteriologic culture of surgical specimens and histopathologic analysis. We compared surgical pathology and preoperative 18F-FDG PET/CT. RESULTS: In the first case studied, the infection was most accurately localized with a SUV with a lower level of 2.00 and an upper of 8.00. Upon comparing the pathological findings and the 18F-FDG PET/CT, we set a SUV with a lower level of 2.00 and an upper level of 8.00. In thirteen cases, infection was detected with positive pathological findings. Preoperative 18F-FDG PET/CT showed high accumulation in these cases. In the remaining three cases, no infection was detected on either pathological findings nor 18F-FDG PET/CT findings. CONCLUSIONS: The infection focus of osteomyelitis was accurately visualized by setting the SUV cut-off lower level to 2.00 and upper level to 8.00. We believe that this 18F-FDG PET/CT technique is helpful for image guided surgery of osteomyelitis.

Skin and hair abnormalities of Cantu syndrome: A congenital hypertrichosis due to a genetic alteration mimicking the pharmacological effect of minoxidil.

Cantu syndrome is an autosomal dominant disorder, first described by Cantu in 1982, that is characterized by congenital hypertrichosis, characteristic facial anomalies and cardiomegaly. Recent investigations have revealed that this syndrome is caused by mutations of ABCC9, which encodes a regulatory subunit of SUR2, an adenosine triphosphate-mediated potassium channel opener, expressed not only in smooth muscle but also in hair follicles. However, the abnormalities of skin and hair in patients with Cantu syndrome have not been well explored. We herein report three Japanese patients with Cantu syndrome and describe their specific skin manifestations and alterations in the histopathology of their hair follicles and sebaceous glands. Similar alterations were shared among those three patients and may be related to the function of SUR2, namely the regulation of hair follicle growth, because SUR2 is a known pharmacological target of minoxidil.

Diagnostic Performance and Safety of Positron Emission Tomography Using 18F-Fluciclovine in Patients with Clinically Suspected High- or Low-grade Gliomas: A Multicenter Phase IIb Trial.

OBJECTIVES: The study objective was to assess the diagnostic performance of positron emission tomography (PET) for gliomas using the novel tracer 18F-fluciclovine (anti-[18F]FACBC) and to evaluate the safety of this tracer in patients with clinically suspected gliomas. METHODS: Anti-[18F]FACBC was administered to 40 patients with clinically suspected high- or low-grade gliomas, followed by PET imaging. T1-weighted, contrast-enhanced T1-weighted, and fluid-attenuated inversion recovery (or T2-weighted) magnetic resonance imaging (MRI) scans were obtained to plan for the tissue collection. Tissues were collected from either "areas visualized using anti-[18F]FACBC PET imaging but not using contrast-enhanced T1-weighted imaging" or "areas visualized using both anti-[18F]FACBC-PET imaging and contrast-enhanced T1-weighted imaging" and were histopathologically examined to assess the diagnostic accuracy of anti-[18F]FACBC-PET for gliomas. RESULTS: The positive predictive value of anti-[18F]FACBC-PET imaging for glioma in areas visualized using anti-[18F]FACBC-PET imaging, but not visualized using contrast-enhanced T1-weighted images, was 100.0% (26/26), and the value in areas visualized using both contrast-enhanced T1-weighted imaging and anti-[18F]FACBC-PET imaging was 87.5% (7/8). Twelve adverse events occurred in 7 (17.5%) of the 40 patients who received anti-[18F]FACBC. Five events in five patients were considered to be adverse drug reactions; however, none of the events were serious, and all except one resolved spontaneously without treatment. CONCLUSION: This Phase IIb trial showed that anti-[18F]FACBC-PET imaging was effective for the detection of gliomas in areas not visualized using contrast-enhanced T1-weighted MRI and the tracer was well tolerated.

Verification of the tumor volume delineation method using a fixed threshold of peak standardized uptake value.

We aimed to determine the difference in tumor volume associated with the reconstruction model in positron-emission tomography (PET). To reduce the influence of the reconstruction model, we suggested a method to measure the tumor volume using the relative threshold method with a fixed threshold based on peak standardized uptake value (SUVpeak). The efficacy of our method was verified using 18F-2-fluoro-2-deoxy-D-glucose PET/computed tomography images of 20 patients with lung cancer. The tumor volume was determined using the relative threshold method with a fixed threshold based on the SUVpeak. The PET data were reconstructed using the ordered-subset expectation maximization (OSEM) model, the OSEM + time-of-flight (TOF) model, and the OSEM + TOF + point-spread function (PSF) model. The volume differences associated with the reconstruction algorithm (%VD) were compared. For comparison, the tumor volume was measured using the relative threshold method based on the maximum SUV (SUVmax). For the OSEM and TOF models, the mean %VD values were -0.06 ± 8.07 and -2.04 ± 4.23% for the fixed 40% threshold according to the SUVmax and the SUVpeak, respectively. The effect of our method in this case seemed to be minor. For the OSEM and PSF models, the mean %VD values were -20.41 ± 14.47 and -13.87 ± 6.59% for the fixed 40% threshold according to the SUVmax and SUVpeak, respectively. Our new method enabled the measurement of tumor volume with a fixed threshold and reduced the influence of the changes in tumor volume associated with the reconstruction model.

Clinical Value of FDG-PET/CT for the Evaluation of Rheumatic Diseases: Rheumatoid Arthritis, Polymyalgia Rheumatica, and Relapsing Polychondritis.

FDG is a tracer for visualizing glucose metabolism. PET/CT using FDG is widely used for the diagnosis of cancer, because glycolysis is elevated in cancer cells. Similarly, active inflammatory tissue also exhibits elevated glucose metabolism because of glycolysis in activated macrophages and proliferating fibroblasts. Elevated FDG uptake by active inflammatory tissues, such as those affected by arthritis, vasculitis, lymphadenitis, and chondritis, has enabled the diagnosis of inflammatory diseases using FDG-PET/CT. Rheumatoid arthritis (RA) is a systemic, chronic inflammation of the joints resulting in synovitis. Several clinical studies of RA have demonstrated that FDG uptake in affected joints reflects the disease activity of RA, with strong correlations between FDG uptake and various clinical parameters having been noted. Furthermore, the use of FDG-PET for the sensitive detection and early monitoring of the response to RA therapy has been reported. RA is sometimes associated with subclinical vasculitis, which is related to systemic inflammation. FDG-PET/CT can be used to evaluate subclinical vasculitis in the aorta or carotid artery. Polymyalgia rheumatica (PMR) is an autoimmune musculoskeletal disease of unknown etiology characterized by pain and stiffness in the shoulder, neck, and pelvic girdle, but not in the small finger joints in the hands, together with fever, fatigue, and weight loss. There is no specific test for PMR, and its diagnosis is based on clinical diagnostic criteria and the exclusion of other diseases with similar symptoms. However, FDG-PET/CT reveals a characteristic FDG uptake by the bursitis in ischial tuberosity, greater trochanter, lumbar or cervical spinous process, and scapulohumeral joint. A combination of FDG-PET/CT findings showed a high diagnostic value for PMR in a differential diagnosis from RA. FDG-PET/CT is also very useful for evaluating large vessel vasculitis, which is often associated with PMR. Relapsing polychondritis is a rare multisystem disease of unknown etiology involving cartilaginous and proteoglycan-rich structures. Its rarity and diversity of symptoms often result in a delayed diagnosis. FDG-PET/CT reveals unique FDG uptake findings for chondritis in the auricular, nasal, trachea, bronchial tree, and costal cartilage and in the cartilage of joints. Thus, the spread of knowledge regarding these very specific FDG-PET/CT findings could promote the early diagnosis and improved disease control of relapsing polychondritis.

Phase IIa clinical study of [18F]fluciclovine: efficacy and safety of a new PET tracer for brain tumors.

OBJECTIVE: [18F]Fluciclovine (anti-[18F]FACBC) has demonstrated diagnostic efficacy for cancers of the brain where [18F]fludeoxyglucose has limitations. We conducted a phase IIa study of anti-[18F]FACBC to assess its accumulation pattern and safety in patients with malignant glioma. METHODS: Five patients with glioma scheduled for brain tumor resection received anti-[18F]FACBC. Brain positron emission tomography (PET) was performed following intravenous administration of anti-[18F]FACBC, and subsequently, preoperative gadolinium contrast-enhanced T1-weighted (CE-T1W) magnetic resonance imaging (MRI) was performed for surgery. Specimens for histopathological evaluation were collected during surgery, and their location was precisely determined on CE-T1W MRI and anti-[18F]FACBC PET/CT images. In addition, tumor extent defined on the MRI and PET/CT images was compared. To determine time-activity curves for anti-[18F]FACBC uptake in brain tumor and normal tissues, regions of interest were set in the brain tumor, contralateral normal tissue and the cerebellum, and their standardized uptake values (SUV) were calculated. The safety of anti-[18F]FACBC was assessed based on subjective symptoms and objective findings, electrocardiograms, vital signs, laboratory results, and the incidence of adverse events. RESULTS: Anti-[18F]FACBC accumulated in the malignant gliomas of all patients. CE-T1W MRI detected gliomas in all patients, but anti-[18F]FACBC PET/CT generally delineated wider regions of tumor extent than CE-T1W MRI. Two of the histopathologically confirmed tumors were located in regions that were defined using anti-[18F]FACBC PET/CT, but not using CE-T1W MRI. Two patients experienced three mild adverse events: one complained of a dull headache and later a mild headache, and the other showed general malaise. These symptoms resolved spontaneously without treatment. Only the mild headache could not be ruled out from having a causal relationship with anti-[18F]FACBC. Favorable T/N ratios regarding anti-[18F]FACBC uptake between tumors and normal control tissues were demonstrated in this trial. CONCLUSIONS: It is suggested that anti-[18F]FACBC PET/CT has the ability to delineate glioma spread that is undetectable using CE-T1W MRI. Anti-[18F]FACBC is safe in patients with malignant glioma. This study was registered in the Japan Pharmaceutical Information Center Clinical Trials Information, which is one of the World Health Organization registries (registration number: JapicCTI-111387).

Comparison of 11C-4DST and 18F-FDG PET/CT imaging for advanced renal cell carcinoma: preliminary study.

PURPOSE: 4'-[Methyl-(11)C]-thiothymidine (4DST) has been developed as an in vivo cell proliferation marker based on its DNA incorporation mechanism. This study evaluated the potential of 4DST PET/CT for imaging cellular proliferation in advanced clear cell renal cell carcinoma (RCC), compared with FDG PET/CT. Both 4DST and FDG uptake were compared with biological findings based on surgical pathology. METHODS: Five patients (3 men and 2 women; mean (±SD) age 64.8 ± 11.0 years) with a single RCC (mean diameter: 9.3 ± 3.2 cm) were examined by PET/CT using 4DST and FDG. The dynamic emission scan of 4DST for RCC over 35 min followed by a static emission scan of the body for 4DST and FDG. Then we compared the maximum standardized uptake value (SUVmax) of 20 areas of RCC on both 4DST and FDG images with (1) the Ki-67 index of cellular proliferation (2) Fuhrman grade system for nuclear grade (G) in RCC and (3) pathological phosphorylated grade of mammalian target of rapamycin (pmTOR). RESULTS: All patient cases showed clear uptake of FDG and 4DST in RCC tumors, with mean 4DST SUVmax of 7.3 ± 2.2 (range 4.3-9.4) and mean FDG SUVmax of 6.0 ± 2.8 (range 3.4-10.4). The correlation coefficient between SUVmax and Ki-67 index was higher with 4DST (r = 0.61) than with FDG (r = 0.43). Tumor 4DST uptake (G0: 1.4, G2: 2.6, G2 5.6, G4: 5.7) and tumor FDG uptake (G0: 1.8, G2: 2.9, G2 3.7, G4: 4.1) were both related to Fuhrman grade system. The 4DST uptake increased as the pmTOR grade increases (G0: 3.1, G1: 4.8, G2: 4.7, G3: 6.2); in contrast FDG uptake was unrelated to pmTOR grade (G0: 2.8, G2: 4.0, G2 3.3, G4: 3.6). CONCLUSION: A higher correlation with the proliferation of RCC was observed for 4DST than for FDG. The 4DST uptake exhibits the possibility to predict pmTOR grade, indicating that 4DST has potential for the evaluation of therapeutic effect with mTOR inhibitor in patients with RCC.

18F-FDG PET/CT Findings in Two Cases With Myelodysplastic Syndrome Accompanied by Behçet's Disease.

Recently, the co-occurrence of myelodysplastic syndrome (MDS) and Behçet's disease (BD) has been reported in association with trisomy 8 and HLA 51, with the pathology varying from vasculitis to acute neutrophilic inflammation. We report for the first time about imaging findings of F-fluorodeoxyglucose (FDG) positron emission/computed tomography (PET/CT) in 2 cases having MDS accompanied by BD. In these cases, 18 F-FDG PET/CT images clearly revealed high uptake by bone marrow in MDS and by genital aphthous or ileocecal ulcers in BD. F-FDG PET/CT may be the ideal modality for the detection of comorbidity of MDS and BD.

Evaluation of a new motion correction algorithm in PET/CT: combining the entire acquired PET data to create a single three-dimensional motion-corrected PET/CT image.

PURPOSE: This study evaluated the potential of Q.Freeze algorithm for reducing motion artifacts, in comparison with ungated imaging (UG) and respiratory-gated imaging (RG). PATIENTS AND METHODS: Twenty-nine patients with 53 lesions who had undergone RG F-FDG PET/CT were included in this study. Using PET list mode data, five series of PET images [UG, RG, and QF images with an acquisition duration of 3 min (QF3), 5 min (QF5), and 10 min (QF10)] were reconstructed retrospectively. The image quality was evaluated first. Next, quantitative metrics [maximum standardized uptake value (SUVmax), mean standardized uptake value (SUVmean), SD, metabolic tumor volume, signal to noise ratio, or lesion to background ratio] were calculated for the liver, background, and each lesion, and the results were compared across the series. RESULTS: QF10 and QF5 showed better image quality compared with all other images. SUVmax in the liver, background, and lesions was lower with QF10 and QF5 than with the others, but there were no statistically significant differences in SUVmean and the lesion to background ratios. The SD with UG and RG was significantly higher than that with QF5 and QF10. The metabolic tumor volume in QF3 and QF5 was significantly lower than that in UG. CONCLUSION: The Q.Freeze algorithm can improve the quality of PET imaging compared with RG and UG.

FDG-PET/CT for Detection of Extramedullary Disease in 2 Pediatric Patients With AML.

Positron emission tomography combined with computed tomography (PET/CT) is a promising diagnostic procedure for the detection of extramedullary disease (EMD) in acute myeloid leukemia. We studied 2 children with acute myeloid leukemia who underwent PET to assess for EMD at diagnosis as well as in remission. We detected 5 EMD lesions in 2 cases with PET, only 2 of which were detectable on clinical examination. Our cases show PET's increased sensitivity over physical examination alone in assessing and monitoring the extent of this disease.