Comparison of Ga-68 PSMA PET/CT and Multiparametric MRI for Initial Detection and Staging of Prostate Cancer.

Background Multiparametric magnetic resonance imaging (mpMRI) is widely used for the evaluation of prostate cancer and is known to have better accuracy. Gallium-68 prostate-specific membrane antigen (Ga-68 PSMA) is a radiotracer that shows high localization in prostate cancer cells. Purpose The purpose of this study was to assess the sensitivity and utility of Ga-68 PSMA positron emission tomography/computed tomography (PET/CT) in comparison with mpMRI as a noninvasive imaging technique for the initial diagnosis and locoregional staging of prostate cancer using transrectal ultrasound (TRUS)-guided biopsy as gold standard. Materials and Methods This prospective observational study conducted from August 2017 to April 2020 evaluated 60 men ( n = 60) with biopsy-proven prostate carcinoma. They underwent mpMRI and Ga-68 PSMA PET/CT scans within 14 days with TRUS biopsy being gold standard. T staging of disease, N staging of lymph nodes within the pelvis, and M staging of lesions in pelvic bones (within the imaging field of mpMRI) were compared using PSPP version 1.0.1 statistical software. Results All 60 men with a mean age of 69.9 ± 9.35 years showed Ga-68 PSMA avid disease, whereas 55 were detected by mpMRI. The sensitivity in detection of prostate lesions (with 95% confidence interval) was 99.08% for Ga-68 PSMA PET/CT and 84.40% for mpMRI. Ga-68 PSMA PET/CT detected greater number of patients with regional lymph nodal involvement (19/60) as compared with mpMRI (12/60). Ga-68 PSMA PET/CT showed PSMA avid pelvic skeletal lesions in nine patients, whereas mpMRI detected pelvic lesions in six patients. In addition, four other patients showed extrapelvic skeletal lesions on Ga-68 PSMA PET/CT. Conclusion Ga-68 PSMA PET/CT has superior sensitivity in detection of primary prostate tumor, as compared with mpMRI. Both modalities correlate well in detection of seminal vesicle involvement. Ga-68 PSMA PET/CT outperformed mpMRI in detection of lymph nodal and skeletal metastases. Hence, Ga-68 PSMA PET/CT should be considered as first-line diagnostic modality for carcinoma prostate. Summary Statement : Ga-68 PSMA PET/CT shows superior diagnostic performance than mpMRI in the evaluation of prostate cancer.

Ga68-FAPI Imaging and Lu177-FAPI Therapy in a Case of Metastatic Solitary Fibrous Tumor.

Solitary fibrous tumor (SFT) of the central nervous system (previously called hemangiopericytoma) is a rare mesenchymal tumor. Malignant SFT has a tendency to recur after surgery and can metastasize to distant organs. Treatment options for metastatic disease are limited. This case demonstrated high expression of FAP (fibroblast activating protein) in all metastatic sites with Ga-FAPI positron emission tomography-computed tomography imaging. Subsequently, the patient was treated with Lu177-FAPI-targeted radionuclide therapy. There was significant clinical response. There was mild partial morphological response seen on follow-up imaging.

A Pictorial Essay of Somatostatin Receptor Imaging in Tumor-Induced Osteomalacia: A Single Institutional Experience.

Tumor-induced osteomalacia (TIO) is a rare cause of severe debilitating osteomalacia, due to hypophosphatemia. A strong clinical suspicion based on biochemical parameters can lead to the search for a culprit tumor in the body. The disease entity is more commonly caused by benign mesenchymal tumors. While many imaging modalities have been tried, it is now known that these tumors show high somatostatin receptor (SSTR) expression. Hence SSTR receptor imaging has emerged as a useful diagnostic tool. Here we present a series of TIO cases with clinical presentation and imaging characteristics.

Assessing vaccine introduction and uptake timelines in Gavi-supported countries: are introduction timelines accelerating across vaccine delivery platforms?

BACKGROUND: Previous studies identified factors influencing regulatory approval to introduction timelines for individual vaccines. However, introduction and uptake timelines have not been comprehensively assessed across the portfolio of Gavi-supported vaccines. METHODS: We analysed median times between introduction milestones from vaccine licensure to country introduction and uptake across six vaccine-preventable diseases (VPDs), three delivery platforms and 69 Gavi-supported countries. Data were gathered from public, partner and manufacturer records. VPDs and prequalified vaccines analysed included Haemophilus influenzae type b (DTwP-HepB-Hib, pentavalent), pneumococcal disease (pneumococcal conjugate vaccine, PCV), rotavirus diarrhoea (rotavirus vaccine, RVV), cervical cancer (human papillomavirus vaccine, HPV), polio (inactivated polio vaccine, IPV) and meningococcal meningitis (meningococcal group A conjugate vaccine, MenA). RESULTS: Median time from first vaccine licensure to first Gavi-supported country introduction across VPDs at a 'global level' (Gavi-supported countries) was 5.4 years. Once licensed, MenA vaccines reached first introduction fastest (campaign=0.6 years; routine immunisation (RI)=1.7 years). Most introductions were delayed. Country uptake following first introduction was accelerated for more recently Gavi-supported RI vaccines compared with older ones. CONCLUSION: Factors accelerating timelines across delivery platforms included rapid product prequalifications by WHO, strong initial recommendations by the WHO Strategic Advisory Group of Experts (SAGE) on Immunization, achieving target product profiles on first vaccine licensure within a VPD and completing several VPD milestones at a global level prior to licensure. Milestones required for introduction in Gavi-supported countries should start prior or in parallel to licensure to accelerate uptake of vaccines delivered through diverse delivery platforms.

Situational assessment of adult vaccine preventable disease and the potential for immunization advocacy and policy in low- and middle-income countries.

By 2050, the number of adults over 65 years of age will be double the under-5 population, and heavily concentrated in low- and middle-income countries. Population growth and increasing life expectancies call for effective healthy aging strategies inclusive of immunization to reduce the burden of vaccine-preventable diseases, improve quality of life, and mitigate antimicrobial resistance. Based on a review of available literature on the pneumococcal disease, influenza, and herpes zoster epidemiology and economic burden, and the health systems and policy barriers for adult immunization, we identified evidence gaps and considerations for prioritizing adult immunization. The body of evidence for adult immunization and the health and economic burden of adult disease is heavily concentrated in high-income countries. The few countries reporting adult immunization policies generally focus on high-risk groups. Despite robust child immunization programs in most countries, adult immunization programs and policies lag far behind and there is a general lack of appropriate delivery platforms. Global adult disease burden and economic costs are substantial but evidence from low- and middle-income countries is limited. There is a need for a strengthened evidence base and political commitment to drive a comprehensive, global technical consensus on adult immunization.

Tc 99m Sestamibi Scanning in Multiple Myeloma--a New look with SPECT-CT.

UNLABELLED: A variety of diagnostic tools including biochemistry, radiological imaging bone marrow studies and recently metabolic imaging with FDG PET are used for assessment of disease extent in myeloma. AIM: To evaluate the role of metabolic imaging with Tc99m Sestamibi (Mibi) SPECT-CT in Multiple myeloma. MATERIALS AND METHODS: Patients in various stages of Myeloma were scanned after 20mCi Tc99m Sestamibi was injected i/v. Whole body planar scans were obtained with a dual head gamma camera and SPECT-CT imaging was done. Images were analyzed for degree and extent of abnormal Mibi uptake, extent of lesions seen on low-dose CT and fusion of these images. RESULTS: 112 Whole body Sestamibi Scans were performed in 84 patients (46 Males; 38 Females). Out of these 24 (28.5%) were recently diagnosed cases (Pre-therapy); 35 (41.7 %) were follow-up cases who had received Chemotherapy in the past (Post-therapy), there were 2 cases (2.3%) of Smouldering Myeloma, 4 cases (4.7%) of Plasmacytoma, 13 cases (15.5%) of MGUS (Monoclonal gammopathy of Unknown Significance) and 3 cases (3.6%) of suspected Myeloma (not biopsy confirmed). Myeloma lesions showed good concentration of Mibi. Additionally, the CT scan component of SP.ECT-CT allowed visualization of osteolytic lesions of myeloma. Mibi uptake becomes positive on scan earlier than radiological changes and in follow-up cases, the presence or absence of Mibi uptake could differentiate active from old burnt-out lesions. Whole body scan could detect additional lesions in Plasmacytoma patients. Patients of MGUS showed poor concentration of Sestamibi. CONCLUSION: Whole body Sestamibi Imaging (WBSI) is very useful for evaluating the extent of disease in multiple myeloma. Being a metabolic imaging modality it is superior to radiological (X-ray or CT) assessment alone, and where FDG PET scan is not available, it is a valuable tool for myeloma assessment at a much lower cost.

An unusual case of gallium scan mimicking a bone scan.

Gallium-67 localization is based on the fact that it binds to plasma proteins like transferrin and lactoferrin, which have iron-binding sites. Abnormal biodistribution of gallium-67 citrate can occur in iron-overload states. We report one such case of gallium scan mimicking a bone scan due to skeletal uptake of gallium.

Assessment of diastolic heart function--experience with 16-gated myocardial perfusion SPECT.

BACKGROUND: Ischaemic heart disease (IHD) is a major health problem today. However the focus has shifted primarily to angiographically detecting epicardial vessel stenoses, and ways and means of surgically correcting the blocks. Patients are often not fully evaluated for cardiac function, and diastolic dysfunction of heart, which is often an earlier manifestation than systolic dysfunction, goes undetected. METHODS: Recent gamma cameras have better imaging quality due to attenuation correction with SPECT-CT. 121 patients underwent gated myocardial perfusion imaging (MPI) for suspected coronary artery disease (CAD). We studied the diastolic function of these patients by 16-gated SPECT MPI. RESULTS: 60% patients showed absence of inducible ischaemia on MPI, and hence further invasive procedures like angiography were prevented, 40% showed inducible ischaemia and had to be further evaluated and required intervention. Of all 121 patients, 10% had LV systolic and diastolic dysfunction whereas 66% had isolated diastolic dysfunction. 40% patients had no ischaemia, normal systolic function and only diastolic dysfunction. 40% of these cases had symptoms of chest heaviness/angina equivalent. CONCLUSION: Myocardial perfusion imaging is a useful modality for evaluating patients of suspected CAD and in addition to perfusion data, also provides functional assessment of systolic and diastolic function, which provides comprehensive information regarding patients' symptomatology and can guide further management.