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.

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.

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.

Letjie.maserumule@gmail.com Introduction: Prostate cancer remains a leading cause of mortality despite multiple therapy options. Peptide radioligand therapy (PRLT) with 177Lutetium-prostate specific membrane antigen (¹⁷⁷Lu-PSMA) prolongs survival and improve quality of life in heavily pretreated patients with metastatic castrate resistant prostate cancer (mCRPC). Benefits of earlier introduction of PRLT in chemotherapy-naïve mCRPC patients are still not extensively explored. The aim is to report initial experience of PSA response and progression free survival (PFS) in chemotherapy-naïve mCRPC patients treated with ¹⁷⁷Lu-PSMA. Methods: We retrospectively reviewed 18 chemotherapy-naïve patients with mCRPC who presented for PRLT. The patients received ¹⁷⁷Lu-PSMA at 6–8 weeks intervals with an average activity 8 GBq per cycle. PSA was measured prior each cycle and monitored three monthly after completion of PRLT. PSA response classified as ≥ 50% decline, any decline, and disease progression (≥ 25% increase above baseline). Results: All patients had metastases on ⁶⁸Ga-PSMA PET/CT. Seven and 4 patients had nodal and skeletal metastases only respectively, 6 had both, and 1 had additional lung metastases. All patients had good functional status with Eastern Cooperative Oncology Group score of 0 to 1. All patients had received hormonal therapy, 4 had prostatectomy, and 7 had pelvic radiation. A total of 90 cycles (median 4, range 2–6) were administered. Following the first cycle, decline of 50% or more in PSA was noted in 22% and any decline in 61% of patients. Seven patients’ (39%) PSA increased after one cycle. After the last cycle, all 13 (72%) patients who had a PSA response demonstrated a decline of 50% or more. Ninety percent of patients who had any PSA decline after the initial cycle had durable PSA response of 50% or more. Fifty-seven percent of patients who had an initial increase in PSA progressed. All patients had a follow-up of at least 4 months. The median PFS was 9 months (range 4–36 months). Conclusion: A positive response was noted in this chemotherapy-naïve cohort with durable PSA decline in over 70% of the patients. Relatively prolonged median PFS of 9 months was seen. Article published online: 25 May 2023 © 2023. The Author(s). This is an open access article published by Thieme under the terms of the Creative Commons Attribution License, permitting unrestricted use, distribution, and reproduction so long as the original work is properly cited. (https://creativecommons.org/licenses/by/4.0/) Thieme Medical and Scientific Publishers Pvt. Ltd. A-12, 2nd Floor, Sector 2, Noida-201301 UP, India