Purpose
An appropriate healthy control dataset is mandatory to achieve good performance in voxel-wise analyses. We aimed at evaluating 18FFDG PET brain datasets of healthy controls (HC), based on ...publicly available data, for the extraction of voxel-based brain metabolism maps at the single-subject level.
Methods
Selection of HC images was based on visual rating, after Cook’s distance and jack-knife analyses, to exclude artefacts and/or outliers. The performance of these HC datasets (ADNI-HC and AIMN-HC) to extract hypometabolism patterns in single patients was tested in comparison with the standard reference HC dataset (HSR-HC) by means of Dice score analysis. We evaluated the performance and comparability of the different HC datasets in the assessment of single-subject SPM-based hypometabolism in three independent cohorts of patients, namely, ADD, bvFTD and DLB.
Results
Two-step Cook’s distance analysis and the subsequent jack-knife analysis resulted in the selection of
n
= 125 subjects from the AIMN-HC dataset and
n
= 75 subjects from the ADNI-HC dataset. The average concordance between SPM hypometabolism t-maps in the three patient cohorts, as obtained with the new datasets and compared to the HSR-HC standard reference dataset, was 0.87 for the AIMN-HC dataset and 0.83 for the ADNI-HC dataset. Pattern expression analysis revealed high overall accuracy (> 80%) of the SPM t-map classification according to different statistical thresholds and sample sizes.
Conclusions
The applied procedures ensure validity of these HC datasets for the single-subject estimation of brain metabolism using voxel-wise comparisons. These well-selected HC datasets are ready-to-use in research and clinical settings.
Radioembolization is a valuable therapeutic option in patients with unresectable intrahepatic cholangiocarcinoma. The essential implementation of the absorbed dose calculation methods should take ...into account also the specific tumor radiosensitivity, expressed by the α parameter. Purpose of this study was to retrospectively calculate it in a series of patients with unresectable intrahepatic cholangiocarcinoma submitted to radioembolization. Twenty-one therapeutic procedures in 15 patients were analysed. Tumor absorbed doses were calculated processing the post-therapeutic
Y-PET/CT images and the pre-treatment contrast-enhanced CT scans. Tumor absorbed dose and pre- and post-treatment tumor volumes were used to calculate α and α
parameters (dividing targeted liver in n voxels of the same volume with specific voxel absorbed dose). A tumor volume reduction was observed after treatment. The median of tumor average absorbed dose was 93 Gy (95% CI 81-119) and its correlation with the residual tumor mass was statistically significant. The median of α and α
parameters was 0.005 Gy
(95% CI 0.004-0.008) and 0.007 Gy
(95% CI 0.005-0.015), respectively. Multivariate analysis showed tumor volume and tumor absorbed dose as significant predictors of the time to tumor progression. The knowledge of radiobiological parameters gives the possibility to decide the administered activity in order to improve the outcome of the treatment.
A significant number of studies suggest that coffee consumption reduces cancer risk. This beneficial effect is usually ascribed to the presence of polyphenolic antioxidants and anti-inflammatory ...agents, including caffeine, cafestol, kahweol, and chlorogenic acids. To summarize recent literature on this subject, we performed a bibliographic search in PubMed and Embase over the period January 2005 to December 2020 to identify cohort studies and meta-analysis (with data collection ensuring quality of selected reports) that could provide quantitative data on the relationship between coffee consumption and common cancers. The totality of eligible scientific articles supports the evidence that coffee intake is inversely associated with risk of hepatocellular cancer and, to a slight extent, risk of breast cancer among postmenopausal women. As to the association with other organs, including the esophagus, pancreas, colorectum, kidneys, bladder, ovaries, and prostate, the results are less clear as reports reveal conflicting results or statistically nonsignificant data. Therefore, this overview does not provide broad-based conclusions. Important uncertainties include general study design, inhomogeneous patient sampling, different statistical analysis (deliberate), misreporting of socioeconomic status, education, coffee-brewing methods, consumption of caffeinated or decaffeinated coffee, smoking habits, and alcohol intake. Clearly, more epidemiologic research needs to be conducted before solid science-based recommendations can be made with regard to coffee consumption.
Objectives
The relationship between glucose metabolism and tumor cellularity before chemo-radiotherapy in patients with head and neck squamous cell carcinoma (SCC) has never been compared with that ...of patients evaluated after treatment. This retrospective study analyzed the correlation between glucose metabolism parameters expressed by standardized uptake value (SUV) derived from 18F-fluorodeoxyglucose (18F-FDG) PET/CT and cellularity tumor parameters expressed by apparent diffusion coefficients (ADC) derived from diffusion-weighted (DW) MRI in untreated and treated patients with head and neck SCC.
Methods
In 19 patients with no previous exposure to any treatment and 17 different chemo-radiotreated patients with head and neck SCC, we correlated the semi-quantitative uptake values (SUVmax, SUVpeak, and SUVmean) with the ADC functional parameters (ADCmin, ADCmean) including the standard deviation of ADC values (ADCsd).
Results
No significant correlation was found between glucose metabolism parameters and ADCmin or ADCmean in untreated and treated patient groups. However, in untreated patients, significant inverse correlations were found between ADCsd and SUVmax (
P
= 0.039,
r
= −0.476), SUVpeak (
P
= 0.003,
r
= −0.652) and SUVmean (
P
= 0.039,
r
= −0.477). Analyses after chemo-radiotherapy in 17 patients showed no significant correlation between glucose metabolism parameters and DW MRI values, excluding a persistent significant (but lower intensity) inverse correlation between SUVpeak and ADCsd (
P
= 0.033,
r
= −0.519).
Conclusions
The demonstrated relationships suggest complex interactions especially between metabolic activity and heterogeneity of tumoral tissue, which might play a complementary role in the assessment of head and neck SCC.
Trial date of registration and registration number
Our retrospective study was registered on April 9th, 2020 by the Ethics Committee of the Coordinating Center “Area Vasta Nord Ovest” (CEAVNO) with Registration Number CEAVNO09042020.
Purpose
The aim of this meta-analysis was to compare the reported sentinel lymph node detection rate (SDR), false-negative rate (FNR), and negative predictive value (NPV) as measures of performance ...of sentinel lymph node biopsy (SNB) techniques based on the use of radio-colloids, in clinically neck-negative T1/2 oro-oropharyngeal squamous cell carcinoma.
Methods
Studies were stratified according to the SNB technique: (1)
99m
Tc-nanocolloid planar lymphoscintigraphy with the use of intra-operative hand-held gamma-probe (L-G); (2) L-G with the additional contribution of pre-operative SPECT/CT (L-SPECT/CT-G); (3) L-G with the additional contribution of intra-operative blue dye or indocyanine green optical tracers (L-G-O); (4) L-SPECT/CT-G with the additional contribution of optical tracers (L-SPECT/CT-G-O). The SDRs were summarized accordingly. To summarize the FNRs and NPVs: (i) the index test (SNB) was based on histological evaluation of resected sentinel lymph nodes (SLN) performed on immunohistochemistry and step serial sectioning; (ii) the reference standards were the elective neck dissection or follow-up for tumor-free SNB.
Results
From a total of 3693 patients, the overall SDRs for the L-G, L-SPECT/CT-G, L-G-O, and L-SPECT/CT-G-O techniques were 98.2% (95% CI 97–99.1), 98.9% (95% CI 97.5–99.7), 97.4% (95% CI 95.3–98.9), and 98% (95% CI 95.8–99.2). From a total of 1634 patients, the overall FNRs for the L-G, L-SPECT/CT-G and L-G-O techniques were 8.5% (95% CI 3.4–15.5), 6.2% (95% CI 0.9–15.7), and 9.1% (95% CI 4.3–15.4); moreover, the overall NPVs were 93% (95% CI 90.5–94.9), 91.2% (95% CI 88.3–93.8), and 93.9% (95% CI 90.9–96.3), respectively. Promising initial findings emerged from L-SPECT/CT-G-O.
Conclusions
The superiority of SPECT/CT over planar methods has been reported for providing identification of SLNs by aberrant lymphatic drainage. The additional contribution of optical tracers (mainly represented by blue dye) to the radiocolloid-based techniques did not improve significantly the measures of performance.
Idiopathic normal pressure hydrocephalus (iNPH) is a debated entity with controversial pathogenesis, diagnostic criteria, and predictors of response after ventriculoperitoneal shunt (VPS). ...Parkinsonian signs are frequently reported in the clinical picture, sometimes due to the coexistence of an underlying neurodegenerative parkinsonism and sometimes in the absence thereof. To distinguish these two scenarios is crucial, since they may carry different long-term response to CSF drainage.
123
I-FP-CIT-SPECT was believed to be helpful in this regard, however its role in predicting surgical outcome has been disputed. We illustrate a patient presented with gait disturbance, urinary incontinence, and asymmetrical parkinsonian signs, who underwent a 3T brain MRI and a
123
I-FP-CIT-SPECT. VPS was performed. The patient repeated a
123
I-FP-CIT-SPECT, 18 months after the operation, and was clinically followed up for 24 months. Our patient displayed clinical and radiological criteria for iNPH and an abnormal asymmetrical uptake in
123
I-FP-CIT-SPECT, consistent with her asymmetrical parkinsonism. However, the organization of the substantia nigra studied with iron-sensitive sequences in 3T brain MRI scan appeared intact. The patient revealed an improvement both clinically and in
123
I-FP-CIT-SPECT at postsurgical follow-up. Our report suggests that abnormal
123
I-FP-CIT-SPECT may not necessarily reveal an overlap with neurodegenerative parkinsonism; its partial reversibility may suggest that the mechanical effect exerted on the striatum by ventriculomegaly ultimately leads to downregulation of dopaminergic transporters which may improve after VPS.
Purpose
To assess the presence and pattern of incidental interstitial lung alterations suspicious of COVID-19 on fluorine-18-fluorodeoxyglucose positron emission tomography (PET)/computed tomography ...(CT) (
18
FFDG PET/CT) in asymptomatic oncological patients during the period of active COVID-19 in a country with high prevalence of the virus.
Methods
This is a multi-center retrospective observational study involving 59 Italian centers. We retrospectively reviewed the prevalence of interstitial pneumonia detected during the COVID period (between March 16 and 27, 2020) and compared to a pre-COVID period (January–February 2020) and a control time (in 2019). The diagnosis of interstitial pneumonia was done considering lung alterations of CT of PET.
Results
Overall,
18
FFDG PET/CT was performed on 4008 patients in the COVID period, 19,267 in the pre-COVID period, and 5513 in the control period. The rate of interstitial pneumonia suspicious for COVID-19 was significantly higher during the COVID period (7.1%) compared with that found in the pre-COVID (5.35%) and control periods (5.15%) (
p
< 0.001). Instead, no significant difference among pre-COVID and control periods was present. The prevalence of interstitial pneumonia detected at PET/CT was directly associated with geographic virus diffusion, with the higher rate in Northern Italy. Among 284 interstitial pneumonia detected during COVID period, 169 (59%) were FDG-avid (average SUVmax of 4.1).
Conclusions
A significant increase of interstitial pneumonia incidentally detected with
18
FFDG PET/CT has been demonstrated during the COVID-19 pandemic. A majority of interstitial pneumonia were FDG-avid. Our results underlined the importance of paying attention to incidental CT findings of pneumonia detected at PET/CT, and these reports might help to recognize early COVID-19 cases guiding the subsequent management.
To investigate dopaminergic function in a large cohort of patients with corticobasal syndrome (CBS) and describe its relationship with clinical features in comparison to Parkinson's disease and ...healthy control subjects. In addition, we assessed prevalence and features of individuals with CBS and in vivo evidence of preserved nigral neuronal density.
Substantia nigra pars compacta (SNc) neuronal degeneration is a mandatory pathological criterion for definite corticobasal degeneration, though sporadic autopsy-proven cases with ante-mortem imaging evidence of preserved nigral terminals have been recently described.
In this multicenter study, we investigated presynaptic nigrostriatal function in 36 outpatients fulfilling clinical criteria for "probable corticobasal degeneration" (age 71±7.3 years; disease duration 3.9±1.6 years), 37 PD and 24 healthy control subjects using FP-CIT single photon emission computed tomography. Clinical, neuropsychological, and magnetic resonance imaging assessment was performed to characterize CBS patients. Linear discriminant analysis was used to categorize normal vs. pathological scans.
FP-CIT binding reduction in patients with CBS was characterized by larger variability, more uniform reduction throughout the striatum and greater hemispheric asymmetry compared to PD. Moreover, there was no significant correlation between tracer uptake values and clinical features such as disease duration and severity. Despite all CBS subjects showed obvious bilateral extrapyramidal signs, FP-CIT uptake was found to be normal bilaterally in four CBS patients and only unilaterally in other four cases. Extensive clinical, neuropsychological and imaging assessment did not reveal remarkable differences between CBS subjects with normal vs. pathological FP-CIT uptake.
Our findings support the hypothesis that extrapyramidal motor symptoms in CBS are not invariably associated with SNc neuronal degeneration and that supranigral factors may play a major role in several cases. CBS individuals with normal FP-CIT uptake do not show any clinical or cognitive feature suggesting a different pathology than CBD.
PDF
