15 research outputs found
Current Status of 68Ga-Pentixafor in Solid Tumours
No full textChemokine receptor CXCR4 is overexpressed in neoplasms and its expression is related to tumour invasion, metastasis and aggressiveness. 68Ga-Pentixafor is used to non-invasively image the expression of CXCR4 in tumours and has been widely used in haematological malignancies. Recent evidence shows that therapies targeting CXCR4 can increase the chemosensitivity of the tumour as well as inhibit tumour metastasis and aggressiveness. 68Ga-Pentixafor has shown promise as an elegant radiotracer to aid in the selection of patients whose tumours demonstrate CXCR4 overexpression and who therefore may benefit from novel therapies targeting CXCR4. In addition, its therapeutic partners 177Lu- and 90Y-Pentixather have been investigated in the treatment of patients with advanced haematological malignancies, and initial studies have shown a good treatment response in metabolically active lesions. 68Ga-Pentixafor in solid tumours complements 18F-FDG by providing prognostic information and selecting patients who may benefit from therapies targeting CXCR4. This review summarises the available literature on the potential applications of 68Ga-Pentixafor in solid tumours
Fibroblast Activation Protein Inhibitor (FAPI)-Based Theranostics
No full textFibroblast activation protein (FAP) is a serine protease selectively expressed in cancer-associated fibroblasts (CAFs), fibrotic tissues, and areas of active tissue remodeling, making it an attractive target for diagnostic imaging across a spectrum of disease. FAP inhibitors (FAPIs) labeled with PET tracers have rapidly advanced as a novel imaging modality with broad clinical applications that offers several advantages, including rapid tumor accumulation, low background uptake, and high tumor-to-background ratios. In oncology, FAPI PET has demonstrated excellent performance in visualizing a wide range of malignancies, including those with low glycolytic activity, such as pancreatic cancer, cholangiocarcinoma, and certain sarcomas. Its high sensitivity and specificity for the stromal component enables improved tumor delineation, staging, and response assessment. Additionally, the potential to guide theranostic approaches, where the same tracer can be labeled with therapeutic radionuclides, positions FAPI as a key player in precision oncology. Beyond oncology, FAPI PET has shown promise in imaging conditions characterized by fibrotic and inflammatory processes. In the cardiovascular field, FAPI PET imaging is being investigated for its ability to detect myocardial fibrosis and active cardiac remodeling, crucial in conditions like heart failure, post-myocardial infarction remodeling, and hypertrophic cardiomyopathy. This review highlights the expanding clinical applications of FAPI-based PET imaging across oncology, inflammation, and cardiovascular disease. While the current data are promising, further large-scale studies and multicenter trials are essential to validate these findings and establish standardized protocols. The versatility and broad applicability of FAPI PET underscore its potential as a transformative tool in precision medicine
Current status of Ga-68-pentixafor in solid tumours
No full textChemokine receptor CXCR4 is overexpressed in neoplasms and its expression is related to
tumour invasion, metastasis and aggressiveness. 68Ga-Pentixafor is used to non-invasively image
the expression of CXCR4 in tumours and has been widely used in haematological malignancies.
Recent evidence shows that therapies targeting CXCR4 can increase the chemosensitivity of the
tumour as well as inhibit tumour metastasis and aggressiveness. 68Ga-Pentixafor has shown promise
as an elegant radiotracer to aid in the selection of patients whose tumours demonstrate CXCR4
overexpression and who therefore may benefit from novel therapies targeting CXCR4. In addition, its
therapeutic partners 177Lu- and 90Y-Pentixather have been investigated in the treatment of patients
with advanced haematological malignancies, and initial studies have shown a good treatment
response in metabolically active lesions. 68Ga-Pentixafor in solid tumours complements 18F-FDG by
providing prognostic information and selecting patients who may benefit from therapies targeting
CXCR4. This review summarises the available literature on the potential applications of 68Ga-
Pentixafor in solid tumours.https://www.mdpi.com/journal/diagnosticsam2023Nuclear Medicin
The Role of PET/CT in Breast Cancer
No full textFemale breast cancer has surpassed lung cancer as the most commonly diagnosed cancer worldwide, with an estimated 2.3 million new cases (11.7%), followed by lung cancer (11.4%) The current literature and the National Comprehensive Cancer Network (NCCN) guidelines state that 18F-FDG PET/CT is not routine for early diagnosis of breast cancer, and rather PET/CT scanning should be performed for patients with stage III disease or when conventional staging studies yield non-diagnostic or suspicious results because this modality has been shown to upstage patients compared to conventional imaging and thus has an impact on disease management and prognosis. Furthermore, with the growing interest in precision therapy in breast cancer, numerous novel radiopharmaceuticals have been developed that target tumor biology and have the potential to non-invasively guide the most appropriate targeted therapy. This review discusses the role of 18F-FDG PET and other PET tracers beyond FDG in breast cancer imaging
The clinical utility of 2-deoxy-2-[18F]fluoro-d-glucose positron emission tomography in guiding myocardial revascularisation
No full textINTRODUCTION : Current myocardial revascularisation guidelines recommend that patients with acute coronary syndromes be timeously revascularised. Despite these class I recommendations, immediate access to timeous revascularisation is often not achievable in low- and middle-income countries (LMIC) and remote regions in high-income countries (HIC). Many patients present late outside of the therapeutic window for guideline-recommended interventions. 2-Deoxy-2-[18F]fluoro-d-glucose (2-[18F]FDG) is a radiopharmaceutical agent used to identify cardiac regions with viable or hibernating myocardium. Viable myocytes with impaired contraction may recover their contractility with successful myocardial revascularisation. However, there are conflicting hard outcomes data on patients with hibernating myocardium who are subsequently revascularised. Whether this management strategy results in improved major adverse cardiovascular events remains uncertain.
METHODS : In this narrative review, we will critically appraise the existing body of evidence on whether using 2-[18F]FDG positron emission tomography (PET) in guiding myocardial revascularisation leads to compelling clinical outcomes or not. Furthermore, we will discuss possible reasons for the lack of differences in patient outcomes.
RESULTS : A few randomised controlled trials have challenged the concept of viability testing with 2-[18F]FDG PET. One trial demonstrated that a reduction in mortality could be observed if PET recommendations are followed.
CONCLUSION : The current evidence is insufficient for clinicians in LMIC or remote areas in HIC without access to catheterisation laboratories to refrain from referring patients for viability imaging.http://link.springer.com/journal/403362022-08-13hj2022Nuclear Medicin
Gallium-68 fibroblast activation protein inhibitor positron emission tomography in cardiovascular disease
No full textGallium-68 fibroblast activation protein inhibitor [(68Ga)Ga-FAPI] is a new radiopharmaceutical positioning itself as the preferred agent in patients with malignant tumours, competing with 2-Deoxy-2-[18F]fluoro-d-glucose [2-(18F)FDG] using positron emission tomography (PET). While imaging oncology patients with [68Ga]Ga-FAPI PET, incidental uptake of [68Ga]Ga-FAPI has been detected in the myocardium. This review summarises original research studies associating the visualisation of FAPI-based tracers in the myocardium with underlying active cardiovascular disease
Determination of stream flow reduction associated with afforestation on a selected quaternary catchment of the Crocodile River, Mpumalanga
No full textM.Sc.The foresty industry is a very important industry m South Africa. Forestry is mostly practised in rural areas. Commercial plantations cover only 1.18% of the area of South Africa, with Mpumalanga Province having the largest area and greatest density of commercial plantations. This is because Mpumalanga province is physiographically and climatically conducive to afforestation. The study area, quaternary catchment X22D, is situated in Mpumalanga province; about 80 percent of this catchment is afforested with pine. The hydrological impact of afforestation in the study area is estimated in this study using two models, namely Shell and Affdem3. The impact of afforestation on surface flow depends on the percentage of the afforested area in a catchment, the rotational period, the genera, and the availability of water. As the percentage of afforested area in a catchment increases, so does the consumption of water by the trees increase. This author found that there is a positive relationship between the consumption of water by trees, and the rotational period and the availability of water. Also: Eucalyptus and Pine are consuming more water than Wattle. Understanding these effects of afforestation on water resources at the level of a quaternary catchment is a fundamental requirement in optimal water resource allocation and the long-term sustainable use of water. Keywords: Afforestation, stremflow, hydrological models, riparian zone, afforestation permit system
Juvenile offenders’ rehabilitation programmes in the Department of Correctional Services in Durban management area
No full textThesis submitted in partial fulfillment of the requirements for the Doctor of Philosophy in Management Sciences (Public Administration), Durban, South Africa, 2020.The White Paper on Corrections in South Africa, 2004 makes provision for the
rehabilitation of offenders who are sentenced by the South African courts to between two
years and life imprisonment. The study was aimed at ascertaining if the juvenile offenders
who were serving their respective sentences in the Durban Management Area
participated in rehabilitation programmes because they saw the value, need and
importance in the role that these programmes could play in assisting them to change their
criminal mindsets. The study used the mixed methods approach, where a total of 150
juvenile offenders who were serving their prison terms were sampled. Qualitative in-depth
interviews were targeted whereby the spiritual care worker, three social workers and ten
educators were interviewed. The study was also extended to the ten ex-juvenile offenders
who once participated in the rehabilitation programmes to establish how participating in
rehabilitation programmes benefitted them and whether the acquired skills assisted them
with reintegration into their respective societies and in leading a crime-free life.
The significance of this study emanated from the literature, which points out that the
juvenile offenders and other categories of offenders repeat their crimes after their release.
This, therefore, begs the question: ‘Why is this happening?’ despite the fact Department
of Correctional Services (DCS) has rehabilitation programmes which are aimed at
changing the criminal mindsets of all offenders to desist from committing crime again.
This study was, therefore, expected to find the answer to this question and to assist the
Department of Correctional Services to tailor its rehabilitation programmes in a manner
that will maximally impact the juvenile offenders. The study was also intended to
contribute towards the body of knowledge in the field of behavioural sciences. The
managerial implication of the study was that it might inform the new policy direction that
the Department of Correctional Services might take based on the findings.
The study found that most of the juvenile offenders agreed that they participated in
rehabilitation programmes because they wanted to change their criminal mindsets. 95%
of the juvenile offenders stated that they were positively impacted by the rehabilitation
programmes and therefore, their attitude towards crime and criminality had changed. The study also found that 91% of the juvenile offenders participated in rehabilitation because
they saw the need, value and importance of rehabilitation programmes. Interestingly 93%
of the juvenile offenders mentioned that they would never commit a crime again. It
emerged in the study that juvenile offenders were mostly impacted by the education and
training programmes. It transpired that of the ten ex-juvenile offenders who were
interviewed, five were now university graduates and were employed. Two of the exjuvenile offenders were qualified Chartered Accountants and had had their criminal
records expunged. The other two were lecturers at two institutions of higher learning in
KwaZulu-Natal. One ex-juvenile offender who had B. Comm Accounting degree owned a
property business and employed four graduates who had never been to prison.
It emerged in the study that amongst the challenges faced by ex-juvenile offenders was
the fact that they were unemployable because of their criminal records. In this study, the
author argued that there was tangible evidence that the juvenile offenders in the Durban
Management Area were positively impacted by the rehabilitation programmes delivered
to them. This was evident in education and training programmes. It was also the argument
of this study that criminal records negate all the efforts of ex-juvenile offenders to lead a
crime-free life. This, therefore, meant that there should be a policy shift which would
address this challenge.
The study, therefore, recommended that the current and ex-juvenile offenders should be
provided with entrepreneurial skills so that they could open and manage their businesses
on their release from the prison. This could be an opportunity for institutions like the
Durban University of Technology Entrepreneurial Department to partner with the
Department of Correctional Services as a community outreach programme and roll out
these much-needed entrepreneurial skills to juvenile offenders. This could also be the
Durban University of Technology’s contribution to crime prevention, poverty alleviation
and employment creation.
A Comparison of 68Ga-PSMA PET/CT-Based Split Renal Function with 99mTc-MAG3 Renography in Patients with Metastatic Castration-Resistant Prostate Carcinoma Treated with 177Lu-PSMA
No full textBackground: Physiological PSMA expression in the cells of the proximal renal tubules and consecutive radiopharmaceutical binding and retention could potentially lead to radioligand-therapy-induced nephrotoxicity. Thus, patients with metastatic castration-resistant prostate cancer undergo 99mTc-Mercaptoacetyltriglycine (MAG3) renal scintigraphy to assess kidney function and to exclude renal obstruction as part of their workup for PSMA-targeted radioligand therapy (RLT). 99mTc-MAG-3 renal scintigraphy often requires an additional visit to the nuclear medicine department and patients spend 30–90 min in the department, which is inconvenient and takes up camera time. In addition, the patients are subjected to a baseline 68Ga-PSMA PET/CT to assess for PSMA-positive disease prior to targeted radioligand therapy. The aim of this retrospective cross-sectional study was to compare 99mTc-MAG-3-based split renal function (SRF) with 68Ga-PSMA-derived SRF. Methods: This retrospective cross-sectional study included 28 patients with histologically proven metastatic castration-resistant prostate cancer (mCRPC) who received 177Lu-PSMA617. A comparison between the split renal function using 68Ga-PSMA PET/CT and the 99mTc-MAG-3-derived split renal function was carried out in 56 kidneys (n = 56). The SRF on 68Ga-PSMA was calculated using the volume and the average standard uptake value (SUVmean) within each VOI calculated as previously described by Roser et al.: SRF = (VOLUMEright) ∗ SUVmeanright/(VOLUMEright ∗ SUVmeanright + VOLUMEleft ∗ SUVmeanleft). Paired tests and correlation coefficients were used to compare 68Ga-PSMA and 99mTc-MAG-3. A visual comparison of kidney morphology on both studies was also performed. Results: The median SRF of the right kidney was 49.9% (range: 3–91%) using 68Ga-PSMA PET/CT and 50.5% (range: 0–94%) with 99mTc-MAG3 scintigraphy. Notably, there was a strong correlation between SRF measurements obtained from PSMA and 99mTcMAG3, with a Pearson correlation coefficient of 0.957 (p < 0.001). Both 99mTc-MAG3 and 68Ga-PSMA PET/CT studies identified morphological renal abnormalities; there were nine hydronephrotic kidneys, four shrunken kidneys and one obstructed kidney, and there was a strong positive correlation between 68Ga-PSMA kidney morphology and 99mTcMAG3 renal scintigraphy kidney morphology, with a correlation coefficient of 0.93. Conclusions: PSMA-derived split function demonstrated a high correlation with renal function assessed on diuretic 99mTc-MAG3 renograms. PET-derived split renal function may, therefore, be considered an alternative to diuretic renogram-based split function. Furthermore, both 99mTc-MAG3 and 68Ga-PSMA PET/CT studies identified morphological renal abnormalities such as hydronephrosis, shrunken and obstructed kidneys. This correlation underscores the potential utility of 68Ga-PSMA imaging as a valuable tool for assessing kidney morphology as an alternative to renogram split function in clinical practice
Comparing 68Ga-Pentixafor,18F-FDG PET/CT and Chemokine Receptor 4 Immunohistochemistry Staining in Breast Cancer: A Prospective Cross Sectional Study
No full textBackground. CXCR4 is a chemokine receptor that is frequently overexpressed in invasive breast cancer and plays a major role in tumor proliferation, aggressiveness and metastasis. The aim of this prospective study was to establish the value of CXCR4-directed PET imaging in patients with breast cancer using the novel CXCR4-targeted PET probe 68Ga-Pentixafor by comparing it with 18F-FDG PET/CT (n = 40). Materials and methods. In this prospective cross-sectional study, fifty-one patients with breast cancer aged 36–81 (median (Q1-Q3) 51 (42.5–63)), n = 47 (92%) with initially diagnosed and n = 4 (8%) patients with recurrent breast cancer, underwent CXCR4-targeted PET imaging using 68Ga-Pentixafor. Maximum standardized uptake values (SUVmax), total lesion glycolysis (TLG) or total lesion uptake (TLU), metabolic tumor volume (MTV) and tumor-to-background ratios (TBR) of tumor lesions were measured and correlated with pathological prognostic factors, molecular subtypes and CXCR4 immunohistochemistry (IHC) staining. 18F-FDG PET/CT images were available in 40 of 51 cases (82%) and were compared semi-quantitatively. The patients were followed up for a median of 11 months (range 4–80 months) to determine whether CXCR4 expression correlated with survival. Results. 68Ga-Pentixafor-PET/CT was visually positive in 49/51 (96%) of the cases; in addition, [18F]FDG demonstrated a higher SUVmax compared to 68Ga-Pentixafor. The mean SUVmax was 7.26 ± 2.84 and 18.8 ± 9.1 for 68Ga-Pentixafor and [18F]FDG, respectively. Thirty-seven percent (18/51) of patients had triple-negative breast cancer and 25/51 (49%) had estrogen receptor (ER+) disease. There was a statistically significant correlation between tumor grade, proliferative index (Ki-67) and SUVmax obtained from 68Ga-Pentixafor PET p = 0.002. There was no correlation between the SUVmax obtained from 68Ga-Pentixafor and PET molecular subtypes, estrogen receptor (ER), progesterone receptor (PR) or human epidermal growth factor receptor 2 (HER2) status; however, triple-negative breast cancers had more avid 68Ga-Pentixafor accumulation compared to luminals A and B. The median (Q1–Q3) 68Ga-Pentixafor TLU was significantly higher in HIV-positive (376 (219–881)) compared to HIV-negative (174 (105–557)) breast cancer patients. Conclusions. In conclusion, 68Ga-Pentixafor had a sensitivity of 96% and a specificity of 100% for detecting primary breast cancer; in addition, 68Ga-Pentixafor exhibited significantly higher uptake in patients with higher tumor grade, high proliferative index and triple-negative breast cancer (TNBC), as well as HIV-infected breast cancer patients, highlighting the potential clinical utility and prognostic role of CXCR4-targeted PET imaging in aggressive breast cancer. Notably, 68Ga-Pentixafor complements 18F-FDG by detecting more metastasis in the brain and the skull where FDG has limitations, while 18F-FDG remains superior for detecting skeletal metastasis. Future research should further explore the potential of CXCR4-targeted PET imaging in selecting patients with triple-negative breast cancer and high-grade breast cancer who may benefit from CXCR4-targeted therapies, particularly in the context of HIV co-infection
