16 research outputs found
Differences in Tumour Aggressiveness Based on Molecular Subtype and Race Measured by [18F]FDG PET Metabolic Metrics in Patients with Invasive Carcinoma of the Breast
Breast cancer in women of African descent tends to be more aggressive with poorer prognosis. This is irrespective of the molecular subtype. [18F]FDG PET/CT metrics correlate with breast cancer aggressiveness based on molecular subtype. This study investigated the differences in [18F]FDG PET/CT metrics of locally advanced invasive ductal carcinoma (IDC) among different racial groups and molecular subtypes. Qualitative and semiquantitative readings of [18F]FDG PET/CT acquired in women with locally advanced IDC were performed. Biodata including self-identified racial grouping and histopathological data of the primary breast cancer were retrieved. Statistical analysis for differences in SUVmax, MTV and TLG of the primary tumour and the presence of regional and distant metastases was conducted based on molecular subtype and race. The primary tumour SUVmax, MTV, TLG and the prevalence of distant metastases were significantly higher in Black patients compared with other races (p < 0.05). The primary tumour SUVmax and presence of distant metastases in the luminal subtype and the primary tumour SUVmax and TLG in the basal subtype were significantly higher in Black patients compared with other races (p < 0.05). The significantly higher PET parameters in Black patients with IDC in general and in those with luminal and basal carcinoma subtypes suggest a more aggressive disease phenotype in this race
Impact of COVID-19 on cardiovascular testing in the United States versus the rest of the world
Objectives: This study sought to quantify and compare the decline in volumes of cardiovascular procedures between the United States and non-US institutions during the early phase of the coronavirus disease-2019 (COVID-19) pandemic.
Background: The COVID-19 pandemic has disrupted the care of many non-COVID-19 illnesses. Reductions in diagnostic cardiovascular testing around the world have led to concerns over the implications of reduced testing for cardiovascular disease (CVD) morbidity and mortality.
Methods: Data were submitted to the INCAPS-COVID (International Atomic Energy Agency Non-Invasive Cardiology Protocols Study of COVID-19), a multinational registry comprising 909 institutions in 108 countries (including 155 facilities in 40 U.S. states), assessing the impact of the COVID-19 pandemic on volumes of diagnostic cardiovascular procedures. Data were obtained for April 2020 and compared with volumes of baseline procedures from March 2019. We compared laboratory characteristics, practices, and procedure volumes between U.S. and non-U.S. facilities and between U.S. geographic regions and identified factors associated with volume reduction in the United States.
Results: Reductions in the volumes of procedures in the United States were similar to those in non-U.S. facilities (68% vs. 63%, respectively; p = 0.237), although U.S. facilities reported greater reductions in invasive coronary angiography (69% vs. 53%, respectively; p < 0.001). Significantly more U.S. facilities reported increased use of telehealth and patient screening measures than non-U.S. facilities, such as temperature checks, symptom screenings, and COVID-19 testing. Reductions in volumes of procedures differed between U.S. regions, with larger declines observed in the Northeast (76%) and Midwest (74%) than in the South (62%) and West (44%). Prevalence of COVID-19, staff redeployments, outpatient centers, and urban centers were associated with greater reductions in volume in U.S. facilities in a multivariable analysis.
Conclusions: We observed marked reductions in U.S. cardiovascular testing in the early phase of the pandemic and significant variability between U.S. regions. The association between reductions of volumes and COVID-19 prevalence in the United States highlighted the need for proactive efforts to maintain access to cardiovascular testing in areas most affected by outbreaks of COVID-19 infection
The added value of SPECT/CT in complicated osteomyelitis
ENGLISH ABSTRACT: Background: The detection of bone infection can be very difficult especially in bone with altered
structure due to prior trauma or surgical procedures. Complicated osteomyelitis (COM) is becoming a
public health problem especially with the difficult choice between, high cost surgery and prolonged
courses of intravenous or oral antibiotic therapy, as well as the social and psychological effect of longterm
disease and disability of the patient. The correct localisation of especially bone infection is still a
challenge for the clinician. The single photon emission computed tomography/low dose computed
tomography (SPECT/CT), by fusing the functional information with the anatomical parts, is a wellestablished
tool used in many nuclear medicine studies. This improves the overall quality of the study
with more clear answers. The aim of the study was to determine the added value of SPECT/CT in the
management of complicated osteomyelitis (COM) in patients with endo-prosthesis, post traumatic
osteomyelitis with and without metal implants and diabetic foot.
Methods: This was a prospective study, between February 2010 and February 2012. Patients with
suspected COM who fulfilled the selection and inclusion criteria were included. All had abnormal three
phase bone scan followed by infection imaging with 99mTc labelled white blood cells and 99mTc -colloid if
the99mTc labelled white blood cell study was abnormal. 67Ga citrate was used in vertebral involvement.
Planar and SPECT/CT images were reviewed for presence of abnormal uptake and for its localization in
bone and soft tissue. Scan results were defined as positive or negative. Both planar and SPECT/CT
images were compared regarding diagnosis and precise localization of infection. The final diagnosis was
obtained from surgical specimen or microbiological culture as well as clinical follow-up of all patients.
Results: There were 72 patients, 29 male and 43 female with mean age of 57 yrs [range 27-88].There
were 24 patients with prosthesis, 16 with hip prosthesis (PH=16), and 8 with knee prosthesis (PK=8).
There were 44 patients with post traumatic osteomyelitis, 26 with metal implants (TOM=26) and 18
without metal implants (TOWM= 18). Four patients had diabetic foot (DF= 4). Infection was diagnosed
in 19/72 patients on planar images and in 21/72 on SPECT/CT. Infection was diagnosed in 4 patients
with prosthesis, 16 patients with post traumatic injury and one diabetic foot patient. The four patients
with prosthesis, SPECT /CT added diagnostic value by excluding osteomyelitis in 3 patients and by
defining the exact extent and localizing soft tissue and bone infection (STI/OM) in one patient. In 16
patients with post traumatic OM on planar images, SPECT /CT added diagnostic value, by excluding OM in 4 patients and confirming only STI, better localisation of the uptake in bone
and soft tissue in 5 patients, of them 2 patient was negative on planar, and in 7 patients, confirmed and
defined the exact extent of
both OM and STI. One diabetic foot was positive for STI on the planar, the SPECT/CT added diagnostic
value by defining the extent of the infection.
In summary the added value of SPECT/CT was:
a. Overall infection:
1. Exclusion of osteomyelitis by confirming only soft tissue involvement: 7 patients (10%)
2. Better localization in bone and soft tissue: 6 patients (8%)
3. Better delineation of extent of infection: 9 patients (12%)
4. None: 50 patients (70%)
b. In positive cases only:
1. Exclusion of osteomyelitis by confirming only soft tissue involvement: 7 patients (33%)
2. Better localization in bone and soft tissue: 5 patients (24%)
3. Better delineation of extent of infection: 9 patients (43%)
4. None: 0 patients
The overall sensitivity, specificity, positive predictive value, negative predictive value and accuracy for
infection, on planar was 90%, 100%, 100%, 97%, 97%, respectively and for SPECT/CT 100%, 100%,
100%, 100%, 100%. For OM on planar, the sensitivity, specificity , positive predictive value, negative
predictive value and accuracy was 100%, 89%, 53%, 100%, 90%, respectively and for SPECT/CT 100%,
100%, 100%, 100%, 100%.
Conclusion:
In complicated osteomyelitis, SPECT/CT is useful in localizing, defining the exact extent of infection
where the planar images are abnormal, with no added value if the planar images are negative. We
recommend in clinical practice the routine use of hybrid SPECT/CT imaging in complicated osteomyelitis
when planar images are abnormal.AFRIKAANSE OPSOMMING: Agtergrond: Die opspoor van beeninfeksie is veral moeilik in been wat as gevolg van vorige trauma of
chirurgiese prosedures misvorm is. Gekompliseerde osteomiëlitis word ‘n gesondheidsprobleem veral
as gevolg van die moeilike keuse tussen hoë koste chirurgie en langdurige kursusse binneaarse of orale
antibiotika, asook die sosiale en sielkundige gevolge van langstaande siekte en die gestremdheid van die
pasiënt.
Die korrekte lokalisering van veral beeninfeksie is steeds ‘n uitdaging vir die geneesheer. Enkel foton
emissie rekenaartomografie / lae dosis rekenaartomografie (SPECT/CT), die kombinasie van funksionele
en anatomiese inligting, is ‘n goed gevestigde metode in baie kerngeneeskunde ondersoeke. Dit
verbeter die algemene kwaliteit van die studie met ‘n meer spesifieke antwoord. Die doel van hierdie
studie was om die bykomende waarde van SPECT/CT in die hantering van gekompliseerde osteomiëlitis
in pasiënte met endo-protese, post traumatise osteomiëlitis met en sonder metaal prosteses asook
diabetiese voet te bepaal.
Metode: ‘n Prospektiewe studie is tussen Februarie 2010 en Februarie 2012 gedoen. Pasiënte met
vermoedelik gekompliseerde osteomiëlitis wat aan die keuse en insluitingskriteria voldoen het, is
ingesluit. Almal het abnormale drie-fase beenflikkergramme gehad, gevolg deur infeksiebeelding met
99mTc gemerkte witselle en 99mTc kolloïed indien die 99mTc gemerkte witselstudie abnormaal was.
67Ga sitraat is gebruik wanneer daar werwelaantasting teenwoordig was. Die planare en SPECT/CT
beelde is vergelyk ten opsigte van diagnose en presiese lokalisering van die infeksie. Die finale diagnose
is met behulp van chirurgiese monsters en mikrobiologiese kweking asook die kliniese opvolg van alle
pasiënte bepaal.
Resultate: Die studie het 72 pasiënte, 29 mans en 43 vroue, met gemiddelde ouderdom van 57 jaar [27
– 88 ingesluit]. Daar was 24 pasiënte met prosteses, waarvan 16 met heupprosteses (PH= 16) en 8 met
knieprosteses (PK= 8). Van die 44 pasiënte met post traumatiese osteomiëlitis, het 26 metaal prosteses
(TOM= 26) en 18 geen metaalprosteses gehad nie (TOWM= 18). Vier pasiënte het diabetiese voet gehad
(DF= 4). By 19/72 van die pasiënte is infeksie op die planare beelde gediagnoseer en in 21/72 op die
SPECT/CT beelde. Die bykomende twee gevalle was 1 met TOM en 1 met TOWM.
Infeksie is by 4 pasiënte met prosteses, 16 pasiënte met post traumatiese besering en 1 met diabetiese
voet gediagnoseer. In die vier pasiënte met prosteses, het SPECT/CT ‘n diagnostiese bydrae gelewer om
osteomiëlitis by 3 van die pasiënte uit te skakel en die presiese omvang en lokalisering van sagte weefsel en beeninfeksie (STI/OM) in een pasiënt te bepaal. In 16 pasiënte met
post traumatise osteomiëlitis op die planare beelde, was SPECT/CT van diagnostiese waarde, waar
osteomiëlitis in 4 pasiënte uitgesluit is, en slegs STI bevestig is. Beter lokalisering van die opname in
been en sagte weefsel was in 5 pasiënte moontlik, van wie 2 op die planare beelde negatief was, en in 7
pasiënte bevestig en die presiese omvang met beide OM en STI gedefinieer is. Een diabetiese voet was
positief vir STI op die planare beelde, maar die SPECT/CT het diagnostiese waarde verbeter deur die
omvang van die infeksie beter te toon.
Ter opsomming, was die waarde van die SPECT/CT:
1. Uitsluiting van osteomiëlitis deur slegs van sagte weefsel aantasting te bevestig:
7 pasiënte 10%
2. Beter lokalisering in been en sagte weefsel: 5 pasiënte 7%
3. Beter definisie van omvang van infeksie: 9 pasiënte 12%
4. Geen bykomende waarde: 51 pasiënte 71%
Die algehele sensitiwiteit, spesifisiteit, positiewe voorspellingswaarde, negatiewe voorspellingswaarde
en akkuraatheid vir die opspoor van infeksie vir die planare beelde was 90%, 100%, 100%, 97%, 97%,
onderskeidelik en vir die SPECT/CT 100%, 100%, 100%, 100% en 100%. Vir osteomiëlitis was
sensitiwiteit, spesifisiteit, positiewe voorspellingswaarde, negatiewe voorspellingswaarde en
akkuraatheid van planare beelde 100%, 89%, 53%, 100%, 90%, onderskeidelik en die van SPECT/CT
100%, 100%, 100%, 100% , 100%.
Gevolgtrekking: SPECT/CT is nuttig in die lokalisering en definiëring van die presiese omvang van die
infeksie in gekompliseerde osteomiëlitis in gevalle waar die planare beelde abnormaal is, met geen
bykomende waarde wanneer planare beelde negatief is nie. Ons beveel SPECT/CT beelding as roetine in
kliniese praktyk aan wanneer planare beelde in gekompliseerde osteomiëlitis abnormaal is
False-positive prostate cancer bone metastases on magnetic resonance imaging correctly classified on gallium-68-prostate-specific membrane antigen positron emission tomography computed tomography
Imaging in prostate cancer is important in defining the local extent of disease, nodal involvement, and identifying metastases. Bone scan is the most commonly used modality for identification of bone metastasis in prostate cancer despite its reported low sensitivity and specificity compared to magnetic resonance imaging (MRI) which is the imaging gold standard for bone metastasis. Gallium-68 prostate-specific membrane antigen positron emission tomography-computed tomography (68Ga PSMA PET-CT) imaging is a relatively new addition to the imaging modalities in prostate cancer. This is a report of a patient with high-risk prostate cancer with features consistent with skeletal metastases on MRI but negative for skeletal metastases on bone scan and 68Ga PSMA PET CT. Histology confirmed the absence of skeletal metastases
Differences in Tumour Aggressiveness Based on Molecular Subtype and Race Measured by [<sup>18</sup>F]FDG PET Metabolic Metrics in Patients with Invasive Carcinoma of the Breast
Breast cancer in women of African descent tends to be more aggressive with poorer prognosis. This is irrespective of the molecular subtype. [18F]FDG PET/CT metrics correlate with breast cancer aggressiveness based on molecular subtype. This study investigated the differences in [18F]FDG PET/CT metrics of locally advanced invasive ductal carcinoma (IDC) among different racial groups and molecular subtypes. Qualitative and semiquantitative readings of [18F]FDG PET/CT acquired in women with locally advanced IDC were performed. Biodata including self-identified racial grouping and histopathological data of the primary breast cancer were retrieved. Statistical analysis for differences in SUVmax, MTV and TLG of the primary tumour and the presence of regional and distant metastases was conducted based on molecular subtype and race. The primary tumour SUVmax, MTV, TLG and the prevalence of distant metastases were significantly higher in Black patients compared with other races (p p < 0.05). The significantly higher PET parameters in Black patients with IDC in general and in those with luminal and basal carcinoma subtypes suggest a more aggressive disease phenotype in this race
Optimisation of BMI-based Images for Overweight and Obese Patients – Implications on Image Quality, Quantitative Accuracy and Radiation Dose in Whole Body 18F-FDG PET/CT Imaging.
Abstract
Background - In PET/CT imaging the amount of 18 F-FDG activity injected to patient is mainly based on the patient body weight (BW) or on body mass index (BMI). Imaging overweight and obese patients using standard protocols results quite often in poor diagnostic images. The purpose of this study was to optimise BMI-based whole body 18 F-FDG PET images obtained from overweight and obese patients and assess the added value in terms of image quality, quantitative accuracy and radiation dose in comparison to BW-based images. Methods - The NEMA-IEC-body phantom was scanned on the mCT 128 slices scanner (Siemens Healthineers). The spheres and background were filed with F-18 activity. Spheres-to-background (2.1kBq/mL) ratio was 4:1. Data was reconstructed using the OSEM-TOF-PSF routine reconstruction (2 iterations, 21 subsets, 3mm Gaussian filter). The optimisation was performed by varying number of iterations, number of subsets, filter’s size and type and matrix size. The phantom images were assessed using contrast recovery coefficients (CRCs). The optimised reconstruction was applied to 17 overweight and obese patients. The optimised BMI-based images and BW-based images were compared visually and using signal-to-noise ratio (SNR), SUVmax and SUVpeak measurements. Results- The visual assessment of the optimised phantom images using 1 iteration, 21 subsets, 3mm Hamming filter showed better image quality and CRC values compared to the routine reconstruction. On patient data, the optimised BMI-based images provided better image quality compared to BW-based images in 87.5% of the overweight cases and 66.7% for obese cases. Compared to BW-based images, the optimised BMI-based images resulted in reduction of 18.6% in SUVmax, 10.6% in SUVpeak and 59% in radiation dose for overweight patients. Similar trends were observed in obese patients. SNR improvement on BMI optimised images over BW images was 55% and 59% on overweight and obese patients, respectively. Conclusions - The optimised BMI-based approach using 1 iteration, 21 subsets, 3mm Hamming filter improves image quality, reduces radiation dose and provides, at least, similar quantitative accuracy compared to the BW-based approach for both overweight and obese patients. These findings are compelling enough support to conducting a full assessment of the approach on a large patient population.</jats:p
