Correlation between [68Ga]Ga-FAPI-46 PET Imaging and HIF-1α Immunohistochemical Analysis in Cervical Cancer: Proof-of-Concept.

Hypoxia leads to changes in tumor microenvironment (upregulated CAFs) with resultant aggressiveness. A key factor in the physiological response to hypoxia is hypoxia-inducible factor-1alpha (HIF-1α). [68Ga]Ga-FAPI PET imaging has been demonstrated in various cancer types. We hypothesized that [68Ga]Ga-FAPI PET may be used as an indirect tracer for mapping hypoxia by correlating the image findings to pathological analysis of HIF-1α expression. The [68Ga]Ga-FAPI PET/CT scans of women with cancer of the cervix were reviewed and the maximum and mean standardized uptake value (SUVmax and SUVmean) and FAPI tumor volume (FAPI-TV) were documented. Correlation analysis was performed between PET-derived parameters and immunohistochemical staining as well as between PET-derived parameters and the presence of metastasis. Ten women were included. All patients demonstrated tracer uptake in the primary site or region of the primary. All patients had lymph node metastases while only six patients had distant visceral or skeletal metastases. The mean SUVmax, SUVmean, and FAPI-TV was 18.89, 6.88, and 195.66 cm3, respectively. The average FAPI-TV for patients with additional sites of metastases was higher than those without. Immunohistochemistry revealed varying intensities of HIF-1α expression in all tested samples. There was a positive correlation between the presence of skeletal metastases and staining for HIF-1α (r=0.80;p=0.017). The presence of skeletal metastasis was correlated to the HIF-1⍺ staining (percentage distribution). Furthermore, the FAPI-TV was a better predictor of metastatic disease than the SUVmax.

The Pattern of Neurological Conditions in a Tertiary Institution in Nigeria: Six Years Experience in Ekiti State, Nigeria.

Background: Neurological disorders constitute major causes of morbidity, and globally, they are the leading causes of death. There is a dearth of neurologists in most African countries and the very few available ones are concentrated in urban areas. The cardiovascular and communicable risk factors responsible for most cases of acute and chronic neurological disorders are also prevalent in rural areas. Although patients from the neighbouring states attend the study centre, the majority are indigent. Therefore, there is a need to observe the pattern of these disorders in Ekiti, to appreciate the disease burden as it would help in the judicious allocation of human and other healthcare resources. Methodology: We reviewed the case files of patients seen at the neurology clinic and admitted via the emergency department into the Federal Teaching Hospital, Ido-Ekiti, over a period of 6 years (2016 to 2021). Results: A total of 881patients were seen during the study period, and they were mostly elderly male patients with chronic disorders in which stroke was the most common neurological disorder (44.9%) followed by seizure disorder (13.1%), and neurodegenerative disorders (9.9%). Tumors and myopathies were the least seen disorders. Conclusion: Health literacy on cardiovascular risk factors and even the distribution of manpower and material resources will help reduce the burden of neurological disorders among the attendees of the Ekiti tertiary health institution.

[68Ga]Ga-NODAGAZOL uptake in atherosclerotic plaques correlates with the cardiovascular risk profile of patients.

OBJECTIVES: This study aimed to determine the correlation of [68Ga]Ga-NODAGAZOL uptake in atherosclerotic plaques and the cardiovascular risk profile of patients imaged with positron emission tomography (PET), wherein quantification of uptake was determined by atherosclerotic plaque maximum target-to-background ratio (TBRmax). We also correlated uptake with a history of cardiovascular events. METHODS: We included patients who underwent PET/CT imaging post-injection of [68Ga] Ga-NODAGAZOL. We documented the number of atherosclerotic plaques found in the major arteries on CT and the cardiovascular risks in each patient. We quantified the intensity of tracer uptake in atherosclerotic plaque in the major arteries using the maximum standardized uptake value (SUVmax). The SUVmax of the most tracer-avid plaque was documented as representative of the individual arterial bed. We determined background vascular tracer activity using the mean standardized uptake value (SUVmean) obtained from the lumen of the superior vena cava. The maximum target-to-background ratio (TBRmax) was calculated as a ratio of the SUVmax to the SUVmean. The TBRmax was correlated to the number of atherogenic risk factors and history of cardiovascular events. RESULTS: Thirty-four patients (M: F 31:3; mean age ± SD: 63 ± 10.01 years) with ≥ 2 cardiovascular risk factors were included. Statistically significant correlation between TBRmax and the number of cardiovascular risk factors was noted in the right carotid (r = 0.50; p < 0.05); left carotid (r = 0. 649; p < 0.05); ascending aorta (r = 0.375; p < 0.05); aortic arch (r = 0.483; p < 0.05); thoracic aorta (r = 0.644; p < 0.05); left femoral (r = 0.552; p < 0.05) and right femoral arteries (r = 0.533; p < 0.05). TBRmax also demonstrated a positive correlation to history of cardiovascular event in the right carotid (U = 26.00; p < 0.05); left carotid (U = 11.00; p < 0.05); ascending aorta (U = 49.00; p < 0.05); aortic arch (U = 37.00; p < 0.05); thoracic aorta (U = 16.00; p < 0.05); left common iliac (U = 49.500; p < 0.05), right common iliac (U = 43.00; p < 0.05), left femoral (U = 40.500; p < 0.05) and right femoral (U = 37.500; p < 0.05). CONCLUSION: In this cohort of patients, a positive correlation was noted between atherosclerotic plaque uptake of [68Ga]Ga-NODAGAZOL and the number of atherogenic risk factors which translates to the risk of atherosclerosis and cardiovascular risk factors.

Spectrum of thyroid function test among type 2 diabetic patients attending a rural health facility, southwest Nigeria: A hospital-based study.

Objectives: The thyroid gland produces hormones that have significant influence on carbohydrate metabolism; its disorders may affect carbohydrate metabolism in type 2 diabetic patients (T2DM) more than the non-diabetic (NDM) patients as reported in various studies. We determined the spectrum of thyroid function tests (TFTs) profile among T2DM in our rural health facility. Methods: T2DM patients and NDM patients were recruited for the study. The age, educational level, occupation, marital status, and duration of diabetes were extracted from interviewer's administered questionnaire. The weight, height, body mass indices (BMIs), and the waist and hip circumferences were measured. Waist-hip ratios (WHR) were calculated for all participants. Venous blood was collected and assayed for free triiodothyronine (fT3), free thyroxine (fT4), and thyroid stimulating hormone (TSH) using a Chemiluminescence Immunoassay (CLIA) 2nd Generation Autoanalyzer. The mean, standard deviation, frequencies, and percentages were calculated for the variables. The student's t-test and chi-square test were also determined as appropriate. Results: Seventy-eight patients made up of 56 T2DM and 22 NDM were evaluated in this study. Fifty-one were males while 27 were females; 67.9% and 59.1% of the female participants were T2DM and NDM, respectively. The WHR was significantly higher in T2DM than NDM (0.92 ± 0.05 versus 0.88 ± 0.06). The TSH was higher in T2DM than the NDM. Forty-four (78.6%) of the T2DM had euthyroid (normal) biochemical pattern; 12 (21.4%) showed abnormal biochemical pattern of euthyroid sick syndrome, subclinical hyperthyroid, and subclinical hypothyroid. Thirty (53.6%) of the T2DM were diagnosed less than five years ago. The value of TSH was increasing with the duration of diabetes but not in a statistically significant way. None of the T2DM showed overt hypothyroid or hyperthyroid test result. Conclusion: Thyroid function test may identify diabetics with altered thyroid hormone status that may impact on their metabolic control. Knowledge of the functional state of the thyroid gland can help in achieving a better metabolic control and attenuate the development of complications in T2DM.

An exploration of profile, perceptions, barriers, and predictors of research engagement among resident doctors: a report from CHARTING study.

Purpose/Aims: This research aimed to study the profile, perceptions, barriers, and predictors of Nigerian resident doctors' level of engagement in scientific research. Methods: This study was a descriptive cross-sectional quantitative survey of 438 resident doctors in Nigeria. This study forms a part of the big CHARTING Study, the protocol of which was published in "Nigeria Journal of Medicine 2019;28:198-205." Results: Three hundred and eighteen (72.8%) respondents were male and 119 (27.2%) were female. There were 229 (52.4%) registrars and 208 (47.6%) senior registrars, while residents in surgical versus nonsurgical specialties were 190 (44.5%) and 237 (55.5%), respectively. Three hundred and sixty-eight (85%) respondents had participated previously in research; 67 (15.6%) and 72 (16.6%) had their papers published in local or international journals, respectively; and only 46 (10.6%) had held first authorship positions in peer-reviewed journal publications. The significant barriers to research identified among them included lack of funding, lack of free time, inadequate training/knowledge on research methodology, and the onerous nature of clinical research. The independent predictor of previous engagement with research was years on current job (P = 0.007). This was similar to finding for the first authorship of a peer-reviewed article among the respondents (P = 0.017). Conclusion: This study concludes that publication and grantsmanship rates were very low among the surveyed resident doctors, despite their high rate of engagement in research projects. There is a need for increased research capacity building among resident doctors in Nigeria.

68Ga-PSMA-11 PET/CT Initial Staging in Black and White South African Males with ISUP Grade Group 1 and 2 Prostate Adenocarcinoma.

Prostate adenocarcinoma (PCa) is a leading cause of mortality. Black males with high-risk PCa have a poorer prognosis compared to white males. Patients with International Society of Urological Pathology (ISUP) Grade Group (GG) 1 and 2 PCa have little potential for metastases post radical prostatectomy. 68Gallium prostate specific membrane antigen (68Ga-PSMA) PET/CT imaging for metastatic PCa is superior to conventional imaging in staging high-risk PCa. No strong evidence is available to support imaging low-risk patients. We aimed to evaluate the value of 68Ga-PSMA PET/CT in black and white South African (BSA and WSA) males with GG1 and 2 PCa at initial staging. We evaluated 25 WSA and 123 BSA males. The image findings were correlated with prostate specific antigen (PSA). PSA levels significantly correlated with both primary tumor and whole-body PSMA-tumor volume (PSMA-TV) and were higher in BSA males. No differences were noted in the occurrence of metastases; however, PSA, seminal vesicle invasion and black race predicted metastases. Our findings suggest higher PSMA expression and tumor burden in BSA with histologically low-risk PCa, and future research with immunohistochemistry evaluation will be essential to confirm these findings.

Hematologic toxicity profile and efficacy of [225Ac]Ac-PSMA-617 α-radioligand therapy of patients with extensive skeletal metastases of castration-resistant prostate cancer.

PURPOSE: Actinium-225-labeled prostate-specific membrane antigen ([225Ac]Ac-PSMA-617) is safe and effective in the treatment of metastatic castration-resistant prostate cancer (mCRPC). No study has specifically assessed its safety in patients with extensive skeletal metastases of mCRPC. We aimed to investigate the hematologic toxicity and efficacy of [225Ac]Ac-PSMA-617 therapy in patients with extensive skeletal metastases of mCRPC. METHODS: We retrospectively reviewed the medical record of patients treated with [225Ac]Ac-PSMA-617 for mCRPC. We included patients with a superscan pattern of skeletal metastases and those with 20 or more multifocal sites of skeletal metastases on baseline [68 Ga]Ga-PSMA-11 PET/CT. We reviewed the levels of hemoglobin, white blood cell (WBC), and platelet prior to each cycle of treatment and determined the presence of impaired bone marrow function at baseline and the grade of toxicity in the hematologic parameters induced by treatment. We evaluated the predictors of hematologic toxicity using binary logistic regression analysis. We also determined the presence of renal dysfunction before or during treatment. We assessed response to treatment using prostate-specific antigen response and the progression-free survival (PFS) and overall survival (OS). RESULTS: A total of 106 patients were included. Skeletal metastasis was in the superscan pattern in 34 patients (32.1%) and multifocal in 72 patients (67.9%). The median treatment cycle was 4 (range = 1-9). Ninety-eight patients (92.5%) had abnormal baseline hematologic parameters. One patient had grade 4 thrombocytopenia. Grade 3 anemia, leukopenia, and thrombocytopenia were seen in 1 (0.9%), 3 (2.8%), and 2 (1.9%) patients, respectively. Age, the number of treatment cycles, and the presence of renal dysfunction were significant predictors of hematologic toxicity. Eighty-five patients (80.2%) achieved PSA response. The median PFS and OS of the study population were 14:00 (95%CI: 8.15-19.86) months and 15.0 (95%CI: 12.8-17.2) months, respectively. CONCLUSIONS: [225Ac]Ac-PSMA-617 induces a good anti-tumor effect in about 80% of patients with extensive skeletal metastases of mCRPC with a rare incidence of severe hematologic toxicity. Age, number of treatment cycles, and the presence of renal dysfunction were significant risk factors for hematologic toxicity of [225Ac]Ac-PSMA-617 therapy.

Correlation Between CT Features of Active Tuberculosis and Residual Metabolic Activity on End-of-Treatment FDG PET/CT in Patients Treated for Pulmonary Tuberculosis.

Patients who complete a standard course of anti-tuberculous treatment (ATT) for pulmonary tuberculosis and are declared cured according to the current standard of care commonly have residual metabolic activity (RMA) in their lungs on fluorine-18 fluorodeoxyglucose positron emission tomography/computed tomography (FDG PER/CT) imaging. RMA seen in this setting has been shown to be associated with relapse of tuberculosis. The routine clinical use of FDG PET/CT imaging for treatment response assessment in tuberculosis is hindered by cost and availability. CT is a more readily available imaging modality. We sought to determine the association between CT features suggestive of active tuberculosis and RMA on FDG PET/CT obtained in patients who completed a standard course of ATT for pulmonary tuberculosis. We prospectively recruited patients who completed a standard course of ATT and declared cured based on negative sputum culture. All patients had FDG PET/CT within 2 weeks of completing ATT. We determined the presence of RMA on FDG PET images. Among the various lung changes seen on CT, we considered the presence of lung nodule, consolidation, micronodules in tree-in-bud pattern, FDG-avid chest nodes, and pleural effusion as suggestive of active tuberculosis. We determine the association between the presence of RMA on FDG PET and the CT features of active tuberculosis. We include 75 patients with a mean age of 36.09 ± 10.49 years. Forty-one patients (54.67%) had RMA on their FDG PET/CT while 34 patients (45.33%) achieved complete metabolic response to ATT. There was a significant association between four of the five CT features of active disease, p < 0.05 in all cases. Pleural effusion (seen in two patients) was the only CT feature of active disease without a significant association with the presence of RMA. This suggests that CT may be used in lieu of FDG PET/CT for treatment response assessment of pulmonary tuberculosis.

A Prospective Investigation of Tumor Hypoxia Imaging with 68Ga-Nitroimidazole PET/CT in Patients with Carcinoma of the Cervix Uteri and Comparison with 18F-FDG PET/CT: Correlation with Immunohistochemistry.

Hypoxia in cervical cancer has been associated with a poor prognosis. Over the years 68Ga labelled nitroimidazoles have been studied and have shown improved kinetics. We present our initial experience of hypoxia Positron Emission Tomography (PET) imaging in cervical cancer with 68Ga-Nitroimidazole derivative and the correlation with 18F-FDG PET/CT and immunohistochemistry. Twenty women with cervical cancer underwent both 18F-FDG and 68Ga-Nitroimidazole PET/CT imaging. Dual-point imaging was performed for 68Ga-Nitroimidazole PET. Immunohistochemical analysis was performed with hypoxia inducible factor-1α (HIF-1α). We documented SUVmax, SUVmean of the primary lesions as well as tumor to muscle ratio (TMR), tumor to blood (TBR), metabolic tumor volume (MTV) and hypoxic tumor volume (HTV). There was no significant difference in the uptake of 68Ga-Nitroimidazole between early and delayed imaging. Twelve patients had uptake on 68Ga-Nitroimidazole PET. Ten patients demonstrated varying intensities of HIF-1α expression and six of these also had uptake on 68Ga-Nitroimidazole PET. We found a strong negative correlation between HTV and immunohistochemical staining (r = -0.660; p = 0.019). There was no correlation between uptake on PET imaging and immunohistochemical analysis with HIF-1α. Two-thirds of the patients demonstrated hypoxia on 68Ga-Nitroimidazole PET imaging.

Profile and determinants of intention to migrate by early career doctors in Nigeria: A report from CHARTING study.

INTRODUCTION: Recently, there has been an upsurge in the migration of medical personnel, especially early career doctors (ECDs) from low- and middle-income countries, Nigeria inclusive, to high-income countries with wide-ranging consequences on the social and economic systems of the donor countries. This study assessed the profile and determinants of intention to emigrate by ECDs in Nigeria. METHODS: A cross-sectional study conducted among Nigerian ECDs from nine tertiary hospitals. Socio-demographic characteristics, intention & reasons to emigrate and willingness to return were collected using a self-administered semi-structured questionnaire. Data were analysed using Statistical Package for Social Sciences (SPSS) version 23. RESULTS: A total number of 763 ECDs participated in the study. The majority (88.2%) were less than 40 years of age and the male to female ratio was 2:1. Majority of the participants (69.4%) received monthly income ≤833 US Dollar. About two-thirds of ECDs had plans to emigrate and most to developed countries. Common reasons for intention to migrate were better quality of postgraduate training, improved quality of life and better remuneration. CONCLUSION: High proportion of Nigerian ECDs has intention to emigrate out with potential adverse effect on the fragile health system in the country.

18F-FDG-PET/CT imaging of uterine cervical cancer recurrence in women with and without HIV infection.

BACKGROUND: To compare the rate, time and, pattern of recurrence of cervical cancer between patients with and without HIV infection and to determine factors predicting cervical cancer recurrence in patients evaluated by 18F-FDG-PET/CT. METHODS: We reviewed the 18F-FDG-PET/CT images of patients with histologically proven cervical carcinoma who were presenting with suspected recurrence. We extracted epidemiologic data, previous treatment, histologic subtype, HIV status, viral load and CD4 counts from the electronic laboratory database and the referral form for the 18F-FDG-PET/CT study. RESULTS: We studied 303 women including 112 HIV-infected patients. FIGO stage III disease was present in 131 patients. Of 198 patients with recurrence, 74 were HIV-infected while 124 were not (P=0.849). HIV infected patients were younger (41.99±9.30 years) compared to HIV-uninfected (50.19±11.09), P<0.001. Local recurrence was present in 125 patients while 100 patients had a distant recurrence. Recurrence occurred at a single site in 88 patients and two or more sites in 110 patients. No significant difference in the recurrent patterns between HIV-infected and uninfected patients. Median time to recurrence was 10.50 months (range: 6.00-156.00) among HIV-infected versus 12.00 months (IQR:7.00-312.00) among the uninfected, P=0.065. FIGO stage III (P=0.042) and the presence of histological sub-types other than SCC (P=0.005) were significant predictors of recurrence. HIV infection by itself was not significant in predicting recurrence (P=0.843). CONCLUSIONS: HIV infection has no significant impact on the rate, time or pattern of recurrence in women with suspected cervical carcinoma recurrence. Advanced disease and histological variant other than SCC are predictive of recurrence.

Pattern of Prostate Cancer Recurrence Assessed by 68Ga-PSMA-11 PET/CT in Men Treated with Primary Local Therapy.

Imaging plays a vital role in detecting the recurrence of prostate cancer (PCa) to guide the choice of salvage therapy. Gallium-68 prostate-specific membrane antigen positron-emission tomography/computed tomography (68Ga-PSMA-11 PET/CT) is useful for detecting PCa recurrence. We assessed the pattern of PCa recurrence stratified by serum prostate-specific antigen level and type of primary local treatment in men with biochemical recurrence (BCR) after primary local therapy with radical prostatectomy or external beam radiotherapy (EBRT) using 68Ga-PSMA-11 PET/CT. We reviewed patients imaged with 68Ga-PSMA-11 PET/CT for the localization of the site of PCa recurrence. We determined the site and number of lesions due to PCa recurrence at different PSA levels. A total of 247 men (mean age of 65.72 ± 7.51 years and median PSA of 2.70 ng/mL (IQR = 0.78-5.80)) were included. 68Ga-PSMA-11 PET/CT detected the site of recurrence in 81.4% of patients with a median number of lesions per patient of 1 (range = 1-5). 68Ga-PSMA-11 PET/CT positivity was 43.6%, 75.7%, 83.3%, 90.0%, and 95.8% at PSA levels of <0.5, 0.5-1.0., 1.1-2.0, 2.1-5.0, and 5.0-10.0, respectively. The most common site of recurrence was in the prostate gland/bed at all PSA levels. Pelvic, extra-pelvic, and combined pelvic and extra-pelvic sites of recurrence were seen in 118, 50, and 33 patients, respectively. The risk of extra-pelvic recurrence increases with rising PSA levels. 68Ga-PSMA-11 PET/CT has a high lesion detection rate for biochemical recurrence of PCa in patients previously treated with primary local therapy.

Immune reconstitution inflammatory syndrome-associated Graves disease in HIV-infected patients: clinical characteristics and response to radioactive iodine therapy.

OBJECTIVES: We aimed to describe the clinical characteristics and the response to radioactive iodine (RAI) treatment of immune reconstitution inflammatory syndrome-associated Graves disease (IRIS-GD) in comparison to Graves disease (GD) seen in HIV-uninfected patients. METHODS: We retrospectively reviewed the medical records of patients treated with RAI for GD. We obtained clinical, biochemical and HIV-related information of patients from their medical records. We compared patient characteristics and response to RAI treatment between patients with IRIS-GD and GD seen in HIV-uninfected patients. RESULTS: A total of 253 GD patients, including 51 patients with IRIS-GD, were included. Among IRIS-GD patients, CD4 cell nadir was 66 cells/µL (range: 37-103) with a peak HIV viral load of 60 900 copies/mL (range: 36 542-64 500). At the time of diagnosis of IRIS-GD, all patients had a completely suppressed HIV viraemia with a CD4 cell count of 729 cells/µL (range: 350-1279). The median interval between the commencement of HIV treatment and the onset of GD was 63 months. At 3 months follow-up, the proportion of patients with IRIS-GD achieving a successful RAI treatment outcome (euthyroid/hypothyroid state) was lower than that of HIV-uninfected patients (35.3% vs. 63.4%, respectively; p < 0.001). The response rate remained lower (60.8%) among patients with IRIS GD than among HIV-uninfected GD patients (80.2%, p = 0.004) at 6 months follow-up. After correcting for differences in age, gender and pre-treatment thyroid-stimulating hormone level, there was no significant difference in RAI treatment response between the two groups. CONCLUSIONS: After correcting for possible confounders, the response to RAI treatment was not different between patients with IRIS-GD and GD in HIV-uninfected patients.

The Association of Tumor Burden by 18F-FDG PET/CT and Survival in Vulvar Carcinoma.

PURPOSE: The aim of this study was to assess the impact of 18F-FDG PET/CT metabolic parameters obtained at initial staging of vulva carcinoma on survival in women with and without HIV infection. PATIENTS AND METHODS: 18F-FDG PET/CT images of women with vulva cancer who are planned for definitive therapy were analyzed. SUVmax, SUVmean, MTV, and total lesion glycolysis (TLG) as well as whole-body MTV and whole-body TLG were computed. RESULTS: Twenty-five women were included with a mean age of 43.44 ± 10.32. The majority of the patients were HIV infected with a median CD4 count of 444.00 cells/mm3. The HIV-infected women are younger at diagnosis than their HIV-uninfected counterparts. All patients presented with inguinofemoral lymph node involvement, whereas half the patients had pelvic nodal metastasis. All the patients with distant visceral or skeletal metastasis were HIV infected. The lungs were the most common site of distant metastasis. When comparing the SUVmax, SUVmean, MTV, TLG, wbMTV, and wbTLG between HIV-infected and HIV-uninfected patients, we did not find statistical differences. Twelve patients (48%) were upstaged to metastatic disease. Seven patients had died at the time of analysis. The wbMTV and wbTLG were significantly higher in nonsurvivors than survivors. CONCLUSIONS: 18F-FDG PET/CT improves initial staging of squamous cell carcinoma among women with and without HIV infection. The whole-body tumor burden assessed by 18F-FDG PET metabolic metrics did not differ between HIV-infected and HIV-uninfected women. A higher whole-burden tumor burden is associated with a higher risk of mortality among women with vulva cancer.

Impact of optimized PET imaging conditions on 18F-FDG uptake quantification in patients with apparently normal aortas.

BACKGROUND: The cardiovascular committee of the European Association of Nuclear Medicine (EANM) recently published recommendations on imaging conditions to be observed during 18F-FDG PET imaging of vascular inflammation. This study aimed to evaluate the impact of applying these optimized imaging conditions on PET quantification of arterial 18F-FDG uptake. METHODS AND RESULTS: Fifty-seven patients were prospectively recruited to undergo an early 18F-FDG PET/CT imaging at 60 minutes and repeat delayed imaging at ≥ 120 minutes post tracer injection. Routine oncologic 18F-FDG PET protocol was observed for early imaging, while delayed imaging parameters were optimized for vascular inflammation imaging as recommended by the EANM. Aortic SUVmax of the ascending aorta and SUVmean from the lumen of the superior vena cava (SVC SUVmean) were obtained on early and delayed imaging. Target-to-background ratio (TBR) was obtained for the early and delayed imaging. Aortic SUVmax increased by a mean of 70%, while SVC SUVmean decreased by a mean of 52% between early and delayed imaging (P < 0.001). TBR increased by 122% following delayed imaging. TBR increased, while SVC SUVmean declined across all time-points from 120 to > 180 minutes. Aortic SUVmax significantly increased at imaging time-points between 120 and 180 minutes. No significant improvement in aortic SUVmax was seen at imaging time-points beyond 180 minutes. CONCLUSIONS: 18F-FDG PET imaging conditions optimized for vascular inflammation imaging lead to an improved quantification through an increase in the quantified vascular tracer uptake and decrease in blood-pool background activity.

[68Ga]Ga-Pentixafor for PET Imaging of Vascular Expression of CXCR-4 as a Marker of Arterial Inflammation in HIV-Infected Patients: A Comparison with 18F[FDG] PET Imaging.

People living with human immunodeficiency virus (PLHIV) have excess risk of atherosclerotic cardiovascular disease (ASCVD). Arterial inflammation is the hallmark of atherogenesis and its complications. In this study we aimed to perform a head-to-head comparison of fluorine-18 fluorodeoxyglucose positron emission tomography/computed tomography ([18F]FDG PET/CT) and Gallium-68 pentixafor positron emission tomography/computed tomography [68Ga]Ga-pentixafor PET/CT for quantification of arterial inflammation in PLHIV. We prospectively recruited human immunodeficiency virus (HIV)-infected patients to undergo [18F]FDG PET/CT and [68Ga]Ga-pentixafor PET/CT within two weeks of each other. We quantified the levels of arterial tracer uptake on both scans using maximum standardized uptake value (SUVmax) and target-background ratio. We used Bland and Altman plots to measure the level of agreement between tracer quantification parameters obtained on both scans. A total of 12 patients were included with a mean age of 44.67 ± 7.62 years. The mean duration of HIV infection and mean CD+ T-cell count of the study population were 71.08 ± 37 months and 522.17 ± 260.33 cells/µL, respectively. We found a high level of agreement in the quantification variables obtained using [18F]FDG PET and [68Ga]Ga-pentixafor PET. There is a good level of agreement in the arterial tracer quantification variables obtained using [18F]FDG PET/CT and [68Ga]Ga-pentixafor PET/CT in PLHIV. This suggests that [68Ga]Ga-pentixafor may be applied in the place of [18F]FDG PET/CT for the quantification of arterial inflammation.

FDG PET/CT for evaluating systemic arterial inflammation induced by anthracycline-based chemotherapy of Hodgkin lymphoma: A retrospective cohort study.

To evaluate arterial fluorodeoxyglucose (FDG) uptake as a marker of arterial inflammation in multiple vascular beds in patients treated with anthracycline-based chemotherapy for Hodgkin lymphoma (HL).We used maximum standardized uptake value (SUVmax) and target-to-background ratio (TBR) to quantify arterial FDG uptake in the carotid artery, ascending aorta, abdominal aorta, and femoral artery obtained on positron emission tomography/computed tomography (PET/CT) imaging performed at baseline before chemotherapy and after completion of chemotherapy in patients with HL treated with an anthracycline-containing regimen. We compared the SUVmax and TBR obtained at baseline with that obtained post-chemotherapy for each arterial bed to evaluate the effect of anthracycline-based chemotherapy. We evaluated the effect of cardiovascular risk factors such as human immunodeficiency virus (HIV) infection, smoking, hypertension, and diabetes on the changes in SUVmax and TBR seen in the different arterial beds after anthracycline-based chemotherapy.Fifty-two patients were included with a mean age of 34.56 ±â€Š10.19 years. There were 33 males, and 18 patients were HIV-infected. The mean interval between completion of chemotherapy and follow-up flourine-18 fluorodeoxyglucose positron emission tomography/computed tomography (FDG PET/CT) scan was 65 weeks. We found no significant difference in arterial FDG uptake measured by SUVmax and TBR in all arterial beds between the pre- and post-chemotherapy FDG PET/CT. There was no significant impact of HIV infection, smoking, and hypertension on the changes in arterial FDG uptake following treatment with anthracycline-based chemotherapy.In patients with HL who were treated with anthracycline-based chemotherapy, we found no significant increase in arterial inflammation measured by FDG PET/CT after an average follow-up period of about 65 weeks since completion of chemotherapy.

18F-FDG PET/CT imaging of vulva cancer recurrence: A comparison of PET-derived metabolic parameters between women with and without HIV infection.

OBJECTIVE: To assess the patterns of recurrence of vulva cancer on 18F-FDG PET/CT and to compare the 18F-FDG PET metabolic metrics in patients with and without Human Immunodeficiency Virus (HIV). METHODS: Maximum standardized uptake value (SUVmax), mean standardized uptake value (SUVmean), metabolic tumour volume (MTV and total lesion glycolysis (TLG) were obtained on Flourine-18 Fluorodeoxyglucose Positron Emission Tomography/Computed Tomography (18F-FDG PET/CT) images of women referred with suspected or confirmed vulva cancer recurrence. We compared HIV-infected and HIV-uninfected patients regarding pattern disease recurrence, age at diagnosis, and the PET-derived metabolic indices. RESULTS: We analyzed 33 patients with a mean age 50.76 ± 15.78 including 21 HIV-infected women. The majority of patients (94 %) had squamous cell carcinoma and 84.85 % were Blacks. Of the HIV-infected individuals, the median CD4 count was 526.0 cells/mm3 (IQR: 379.0-729.0). HIV infected patients were younger than the HIV uninfected at the time of diagnosis: 40.50 ±â€Š8.87 vs 66.54 ±â€Š9.71 respectively, p < 0.001. We found a local (vulvar) recurrence rate of 75.8 %. Nodal pelvic recurrences were higher in the HIV-infected patients than in the HIV uninfected patients (70 % vs 30 %, p = 0.027). Three patients had distant metastasis and all three were HIV-infected. There was a higher whole-body MTV and TLG among HIV-infected women compared with HIV-uninfected women, 103.39 vs 17.58 and 852.64 vs 101.79, respectively (p < 0.05 for both). CONCLUSION: HIV-infected women are diagnosed with vulva cancer at a younger age. HIV-infected patients had a higher rate of pelvic lymph node recurrence. There is a higher tumor burden at vulva cancer recurrence among women with HIV infection.

Fluorodeoxyglucose Positron Emission Tomography integrated with computed tomography in carcinoma of the cervix: Its impact on accurate staging and the predictive role of its metabolic parameters.

OBJECTIVES: To determine the impact of FDG-PET/CT in the initial staging of cervical cancer among women with and without HIV and to determine the abilities of FDG-PET/CT metabolic parameters in predicting the presence of distant metastasis. METHODS: We reviewed the FDG-PET/CT images of women with FIGO stage IB2 to IVA carcinoma of the cervix. We compared the FIGO stage before and after FDG-PET/CT. Maximum and mean standardized uptake values (SUVmax and SUVmean), metabolic tumor volume (MTV) and total lesion glycolysis (TLG) of the primary lesion were determined. We compared these parameters between the HIV-infected and uninfected woman and also determined their abilities to predict the presence of distant metastasis. RESULTS: 126 women, mean age 48.05 ± 11.80 years were studied. Seventy-three patients were HIV-infected. The disease was upstaged in 65 patients, 32 of which were upstaged to stage IVB. HIV-infected women were younger (43.36 ± 8.03 years versus 54.51 ± 13.12, p<0.001) and had more advanced disease (p = 0.022) compared with HIV-uninfected. In a univariate logistic regression adjusted for the FIGO stage of the disease, there were significant associations between MTV and TLG of the primary tumor and distant metastasis. SUVmax, SUVmean, MTV and TLG performed well in predicting the presence of distant metastasis with areas under the curves (AUCs) of 0.63, 0.66, 0.80 and 0.77 respectively. These performances improved after adjustment for the FIGO stage of the disease with AUCs of 0.80, 0.79, 0.84 and 0.82 for SUVmax, SUVmean, MTV and TLG respectively. CONCLUSION: Inclusion of 18F-FDG-PET/CT in the pre-therapy assessment of cervical cancer improves the accuracy of staging in about half of the patients. The metabolic parameters of the primary tumor perform well in predicting the presence of distant metastases.

Diagnostic utility of 18F-FDG PET/CT in fever of unknown origin among patients with end-stage renal disease treated with renal replacement therapy.

OBJECTIVE: To evaluate the role of fluorine-18-fluorodeoxyglucose positron emission tomography/computed tomography (18F-FDG PET/CT) in identifying the cause of fever of unknown origin (FUO) in patients on renal replacement therapy (RRT) for end-stage renal disease (ESRD). SUBJECTS AND METHODS: We retrospectively reviewed the 18F-FDG PET/CT scans of 46 patients with a mean age of 39.28±12.50 years on RRT for ESRD. All patients with abnormal scans had histopathologic examination and microbial cultures of tissue samples from areas with increased standardized uptake value maximum (SUVmax) suggesting the cause of FUO in the 18F-FDG PET/CT scan. Fluorine-18-FDG PET/CT was considered helpful if it led to the diagnosis of the cause of FUO after histopathologic and microbiologic examinations. RESULTS: Fluorine-18-FDG PET/CT was helpful in identifying the cause of FUO in 22/46 patients (47.83%). Infection was the cause of fever in all these 22 patients. C-reactive protein (CRP) (P=0.003) and procalcitonin levels (P=0.021) were higher in patients with helpful 18F-FDG PET/CT. No significant difference was found in blood sugar levels and leucocytes counts between patients with helpful 18F-FDG PET/CT outcome and those without. By multiple regression analysis, the odds of a helpful 18F-FDG PET/CT increased with every unit increase in CRP level (OR: 1.009; 95% CI: 1.003-1.016; P=0.005). CONCLUSION: About half of the 18F-FDG-PET/CT scans (22/46) identified the cause of FUO in patients on RRT for ESRD. The clinical utility of 18F-FDG PET/CT in this group of patients is comparable to its average performance in the unselected patients' population evaluated for FUO. A higher CRP level was predictive of a positive 18F-FDG PET/CT outcome.