Validation of Radiosynthesis and First in-Human Dosimetry of Ga-NOTA-UBI-29-41: A Proof of Concept Study.

Antimicrobial peptides (AMPs) such as UBI-29-41 offer a distinctive approach for precise detection due to their unique interactions with bacteria and makes them promising candidates for specific and selective imaging. The study was aimed to corroborate the in-house manual synthesis of Ga-NOTA-UBI-29-41, evaluate its uptake in patients with suspected infection, and estimate of patient-specific dosimetry to ensure optimal clinical application. Ga-NOTA-UBI-29-41 was synthesized by using a variable amount of UBI-29-41 (60-90 μg) to 555 MBq of Ga-68 in 0.

Lead-203 VMT-α-Neuroendocrine Tumor Scintigraphy: A Promising Theranostics Agent.

Targeted alpha therapy (TAT) using lead-212 (Pb-212)-labeled peptides presents an attractive option for the treatment of metastatic neuroendocrine tumors (NETs). As Pb-203 presents an accurate diagnostic surrogate to Pb-212, imaging with Pb-203-labelled peptides can be an important prerequisite to assess the feasibility of TAT with Pb-212-labelled agents. Here, we present the imaging data of a patient with metastatic NET with Pb-203 VMT-α-NET, a somatostatin receptor targeting agent, and demonstrate the matching distribution of Pb-203 VMT-α-NET with Ga-68 DOTANOC.

Potential Efficacy of 68 Ga-Trivehexin PET/CT and Immunohistochemical Validation of αvβ6 Integrin Expression in Patients With Head and Neck Squamous Cell Carcinoma and Pancreatic Ductal Adenocarcinoma.

Purpose: αvβ6 integrin is exclusively expressed in epithelial cells and is upregulated in many carcinomas, such as pancreatic ductal adenocarcinomas (PDACs) and head and neck squamous cell carcinomas (H&NSCCs). Trivehexin is a recently synthesized trimerized αvβ6 integrin selective nonapeptide, which can be labeled with a positron emitter like 68 Ga. This is a pilot study to assess the potential role of 68 Ga-Trivehexin PET/CT in patients with H&NSCC and PDAC and their correlation with αvβ6 integrin expression by the tumor tissue on immunohistochemistry (IHC).

Charting the Course of Targeted α Therapy With First-in-Human, Postadministration Image-Guided Dosimetry and Response Assessment of 212 Pb-VMT-α-NET in Metastatic Neuroendocrine Tumors.

212 Pb emerges as a compelling in vivo α-particle generator for targeted α therapy due to its favorable half-life ( t1/2 = 10.6 hours) aligning with the biological half-lives of small peptides and its potent α-particle emissions within the decay series. However, one of the challenges with 212 Pb is to perform appropriate image-guided dosimetry.

Actinium-225-PSMA radioligand therapy of metastatic castration-resistant prostate cancer (WARMTH Act): a multicentre, retrospective study.

Background: Actinium-225 (Ac) prostate-specific membrane antigen (PSMA) radioligand therapy (RLT) is a novel therapy for metastatic castration-resistant prostate cancer (mCRPC). We aimed to report the safety and antitumour activity of Ac-PSMA RLT of mCRPC in a large cohort of patients treated at multiple centres across the world.

Methods: This retrospective study included patients treated at seven centres in Australia, India, Germany, and South Africa.

The Role of PET-CT-Guided Metabolic Biopsies in Improving Yield of Inconclusive Anatomical Biopsies: A Review of 5 Years in a Teaching Hospital.

Tumour sampling is indispensable to diagnostic and therapeutic decision making. Thus, 18F-FDG PET/CT has the potential to accurately discriminate between viable and non-viable tissues due to its ability to characterise the metabolism of visible tissues. This study's objective was to evaluate the incremental utility of 18F-FDG PET-CT-guided metabolic biopsy in individuals with suspected lesions and a previous negative anatomical biopsy.

Validation of In-House Kit-Like Synthesis of Ga-Trivehexin and Its Biodistribution for Targeting the Integrin αvβ6 Expressing Tumors.

Integrin αvβ6 has become an extremely promising theranostic target for precise delineation of fast-growing malignant cells in the recent years. The aim of the study was to validate the in-house kit-like synthesis of Ga-Trivehexin (integrin αvβ6) and to evaluate its uptake in patients with integrin αvβ6 expressing head and neck and pancreatic cancer. Ga-Trivehexin was synthesized by adding the variable amount of integrin αvβ6 (30-50 μg) to full volume (4-5 mL) Ga-68 in 0.

Incremental Value of 18 F-FDG-Labeled Leukocytes PET/CT Over 18 F-FDG PET/CT Scan in the Detection of Occult Infection.

Purpose: Differentiating infection and sterile inflammation is the main clinical concern of clinicians as they are closely related to each other. Although 18 F-FDG PET/CT imaging is widely used, its main disadvantage is its lack of specificity to discriminate aseptic from septic inflammation. 18 F-WBC PET/CT scan is a promising tool for the accurate diagnosis of infection owing to its high specificity.

Feasibility of F-FDG Labelling of Leucocytes in a Centre Without an On-Site Cyclotron and Monitoring of Radiation Dose to Occupational Worker in the Labelling Procedure.

Differentiation of infection from sterile inflammation is still a major concern for clinicians. The F-WBC positron emission tomography/computed tomography scan has been considered a promising tool for accurate diagnosis of infection owing to its high specificity, but it renders the availability of a medical cyclotron a necessity. The aim of the present study was to determine the feasibility of labeling leukocytes and establish the protocol in a center without the availability of an on-site medical cyclotron.

18F-Labeled WBC PET/CT Scan in a Case of Recurrent Glioblastoma Multiforme, Presented as Pyrexia of Unknown Origin.

Neoplastic causes account for approximately 10% to 20% cases of PUO (pyrexia of unknown origin). The mechanisms by which malignancies induce fever are not fully understood. The release of pyrogenic cytokines either directly from tumor cells or from macrophages responding to tumor are likely to play a major role, which acts on the hypothalamus, causing a change in the thermostatic set point.

Discordant findings of different positron emission tomography/CT tracers in a case of glioblastoma.

F-2-fluoro-2-deoxy-D-glucose ([F]-FDG) positron emission tomography (PET) CT has proven useful in the evaluation of high-grade glioma and is also useful as a predictor of the degree of malignancy in newly diagnosed brain tumors. It is commonly accepted that high-grade gliomas are characterized by increased FDG uptake, whereas the low-grade glioma demonstrates reduced or absent FDG uptake. [F]-FDOPA is an amino acid PET tracer which is a marker of the proliferative activity of brain tumors and demonstrates positive uptake in all grades of brain tumors; however, the degree of tracer uptake is significantly higher in high-grade tumors as compared to low-grade tumors.

18F-FDG PET/CT in Bilateral Breasts Metastasis From Ovarian Carcinoma.

Ovarian carcinomas generally metastasize within the peritoneal cavity due to exfoliation of malignant cells from primary tumor. Metastasis to the breasts is an unusual event and may mimic primary neoplastic disease. Usually, breast metastasis presents as a single isolated, well-circumscribed soft tissue lesion, and serous papillary carcinoma is the most common type of ovarian tumor that can metastasize to the breast.

Radioguided Surgery in Insulinoma Using Ga Labeled Exendin-4: a Case Report.

Laparoscopic resection of tumor is often performed for benign and small insulinomas, or for those located in the body or tail of the pancreas. The precise preoperative and intraoperative localization of the insulinoma is critical to minimize the surgical intervention. Conventional imaging studies, i.

Upfront Use of 177Lu-Labeled PSMA Radioligand Therapy and Treatment Response Assessment in Treatment-Naive Prostate Cancer.

Prostatic malignancy is the most common type of nonskin cancer and associated with significant morbidity and mortality. Early androgen deprivation therapy (ADT) is the treatment of choice in metastatic prostate cancer, whereas ADT delays progression of disease, but it is associated with significant adverse effects and frequently impairs the quality of life. Therefore, there is growing interest in treatments to postpone ADT while achieving a good progression-free survival.

In-House Preparation and Quality Control of Ac-225 Prostate-Specific Membrane Antigen-617 for the Targeted Alpha Therapy of Castration-Resistant Prostate Carcinoma.

Purpose: Ac-225 labeled with prostate-specific membrane antigen (PSMA-617), a transmembrane glycoprotein which is highly expressed in prostate carcinoma cells, is presently being considered a promising agent of targeted alpha therapy for the treatment of patients suffering from metastatic castration-resistant prostate cancer. In the present study, we report an optimized protocol for the preparation of therapeutic dose of Ac-225 PSMA-617 with high yield and radiochemical purity (RCP).

Methods: Ac-225 PSMA-617 was prepared by adding the peptidic precursor-PSMA-617 (molar ratios, Ac-225: PSMA-617 = 30:1) in 1 ml ascorbate buffer to Ac-225 and heating the reaction mixture at 90°C for 25 min to obtain the radiopeptide with high RCP and yield.

Dosimetric analyses of intra-arterial versus standard intravenous administration of 177Lu-DOTATATE in patients of well differentiated neuroendocrine tumor with liver-dominant metastatic disease.

Objective: The aim of the present study was to perform calculation of the absorbed doses to organs at risk and to neuroendocrine tumors and to determine whether hepatic intra-arterial (IA) injection of Lu-DOTATATE Peptide Receptor Radionuclide Therapy (PRRT) would achieve higher intratumoral concentrations than standard intravenous administration of Lu-DOTATATE.

Methods: 29 patients with Grade I-II, inoperable, metastatic gastro-entero-pancreatic neuroendocrine tumor (GEPNET) were prospectively identified and enrolled for the study. 15 patients of GEPNETs with liver-dominant metastatic disease and less than 3 sites of extrahepatic metastatic disease were administered a single dose of Lu-DOTATATE therapy through the selective catheterization of the hepatic artery (IA group).

Invasive Fungal Infection in COVID-19-Recovered Patient Detected on 18F-FDG-Labeled Leukocytes PET/CT Scan.

Occurrence of invasive fungal infections has gained significant attention during recent times in patients with COVID-19. Patients with severe form of COVID-19, such as those treated in the intensive care unit with prolonged steroid use, are particularly vulnerable to secondary bacterial and fungal infections. Disseminated systemic mycosis is a life-threatening condition, especially in immunocompromised patients.

Therapeutic efficacy of Ac-PSMA-617 targeted alpha therapy in patients of metastatic castrate resistant prostate cancer after taxane-based chemotherapy.

Objectives: Ac-PSMA-617 therapy has shown good response in many recent studies. We report our experience of targeted alpha therapy with Ac-PSMA-617 in mCRPC patients who have failed therapy with taxanes.

Materials And Methods: Thirty-eight patients with CRPC with progressive disease following at least one taxane-based chemotherapy received Ac-PSMA-617 between July 2017 and Nov 2019.

Incremental Value of Ga-68 Prostate-Specific Membrane Antigen-11 Positron-Emission Tomography/Computed Tomography Scan for Preoperative Risk Stratification of Prostate Cancer.

Background: Prostate cancer (PC) is the second-most common cause of cancer.Ga-prostate-specific membrane antigen (PSMA)-11 positron-emission tomography/computed tomography (PET/CT) scan help in accurate staging of PC owing to its high PSMA avidity and specificity. The aim of this prospective observational study was to determine the incremental value of Ga-68 PSMA-11 PET/CT over multiparametric magnetic resonance imaging (mpMRI) in the locoregional staging of intermediate- and high-risk PC using histopathology from radical prostatectomy specimens as a gold standard.

Radiation Exposure to the Nuclear Medicine Personnel During Preparation and Handling of Bi-Radiopharmaceuticals.

Because of the excellent ability of α-particles to transfer a high amount of energy over a short tissue range, targeted α-therapy has been attracting rising numbers of nuclear medicine centers. In this study, we estimated the radiation exposure to the occupational workers with pocket dosimeters during handling of the α-emitter Bi, used for targeted α-therapy of neuroendocrine tumor and castration-resistant prostate cancer patients. The dose rates from patients at different distances and time points after injection of the therapy were also evaluated.

Successful Management Of Tumor-Induced Osteomalacia with Radiofrequency Ablation: A Case Series.

Tumor-induced osteomalacia (TIO) is a curable condition when the tumor is correctly located and completely removed. These tumors are, however, small and located in regions that make surgical removal difficult and sometimes risky in some patients. Experience of radiofrequency ablation (RFA) in the management of TIO is limited.

Molecular Imaging to the Surgeons Rescue: Gallium-68 DOTA-Exendin-4 Positron Emission Tomography-Computed Tomography in Pre-operative Localization of Insulinomas.

Background: Insulinoma is an islet-cell neoplasm that secretes insulin. It is usually localized to the pancreas and is often the most common cause of endogenous hyperinsulinemic hypoglycaemia in non-diabetic adult patients. Surgical excision with a curative intent is the standard modality of treatment, and it requires precise localization of tumor tissue.

Dosimetric analysis of patients with gastro entero pancreatic neuroendocrine tumors (NETs) treated with PRCRT (peptide receptor chemo radionuclide therapy) using Lu-177 DOTATATE and capecitabine/temozolomide (CAP/TEM).

Objective:: Two radiosensitizing chemotherapeutic drugs, capecitabine (CAP) and temozolomide (TEM), are administered concurrently to enhance the therapeutic efficacy of peptide receptor radionuclide therapy (PRRT). This study aims to assess the biodistribution and normal-organ and tumor radiation dosimetry for Lu-177 DOTATATE administered concurrently with CAP/TEM.

Methods:: 20 patients with non-resectable histologically confirmed gastroenteropancreatic neuroendocrine tumors with normal kidney function, a normal haematological profile and somatostatin receptor expression of the tumor lesions, as scintigraphically assessed by a Ga-68 DOTANOC scan, were included in two groups-case group (n = 10) and control group (n = 10).

Radiation Dose to the Occupational Worker during the Synthesis of Re-labeled Radiopharmaceuticals in the Nuclear Medicine Department.

Aim: The aim of this study is to estimate whole-body radiation dose to the radiopharmacist involved in labeling of three different Re-labeled compounds, namely, Re-Lipiodol, Re-tin colloid, and Re-hydroxyl-ethylidene-diphosphonate (HEDP) and to compare the occupational burden with the dose limits recommended by Atomic Energy Regulatory Board, India.

Materials And Methods: The Department of Nuclear Medicine at Fortis Memorial Research Institute currently synthesizes three different Rhenium-188 labeled compounds, namely, Re-Lipiodol, Re-HEDP, and Re-tin colloid. To estimate the radiation exposure to the radiopharmacist involved in the synthesis, a survey meter was used to measure radiation level before the start of labeling procedure in the radiopharmacy by keeping it at the location where the radiopharmacist normally stands during preparation.