Comparison of 4D computed tomography and F-18 fluorocholine PET for localisation of parathyroid lesions in primary hyperparathyroidism: A systematic review and meta-analysis.

Minimally invasive parathyroidectomy (MIP) is the standard of care for primary hyperparathyroidism (PHPT). Four dimensional computed tomography(4DCT) and F-18 Fluorocholine positron emission tomography/computed tomography (FCH PET/CT) localize adenomas accurately to perform MIP. We aimed to conduct a systematic review and metanalysis to evaluate the diagnostic performance of 4DCT and FCH PET/CT scan for quadrant wise localisation in PHPT patients and to do head-to-head comparison between these two modalities. DESIGN, PATIENTS AND MEASUREMENT : After searching through PubMed and EMBASE databases, 46 studies (using histology as a gold standard) of 4DCT and FCH PET/CT were included. RESULTS: Total number of patients included were 1651 and 952 for 4DCT scan (studies n = 26) and FCH PET/CT scan (studies n = 24) respectively. In per patient analysis, FCH PET/CT and 4DCT had pooled sensitivities of 92% (88-94) and 85% (73-92) respectively and in per lesion analysis, 90% (86-93) and 79% (71-84), respectively. In the subgroup with negative conventional imaging/persistent PHPT, FCH PET/CT had comparable sensitivity to 4DCT (84% [74-90] vs. 72% [46-88]). As per patient wise analysis, FCH PET/CT had better detection rates than 4DCT ([92.4 vs. 76.85], odds ratio -3.89 [1.6-9.36] p = .0024) in the subpopulation where both FCH PET/CT and 4DCT were reported. CONCLUSION: Both 4DCT and FCH PET/CT scan performed well in newly diagnosed patients, patients with persistent disease and in those with inconclusive conventional imaging results. FCH PET/CT scan had a higher pooled sensitivity than 4DCT in detecting patients with PHPT in head to head comparison.

18F-NaF PET uptake characteristics of coronary artery culprit lesions in a cohort of patients of acute coronary syndrome with ST-elevation myocardial infarction and chronic stable angina: A hybrid fluoride PET/CTCA study.

BACKGROUND: 18F-NaF PET/CT identifies high-risk plaques due to active calcification in coronary arteries with potential to characterize plaques in ST-elevation myocardial infarction (MI) and chronic stable angina (CSA) patients. METHODS: Twenty-four MI and 17 CSA patients were evaluated with 18F-NaF PET/CTCA for SUVmax and TBR values of culprit and non-culprit plaques in both groups (inter-group and intra-group comparison), and pre- and post-interventional MI plaques sub-analysis. RESULTS: Culprit plaques in MI patients had significantly higher SUVmax (1.6; IQR 0.6 vs 1.3; IQR 0.3, P = 0.03) and TBR (1.4; IQR 0.6 vs 1.1; IQR 0.4, P = 0.006) than culprit plaques of CSA. Pre-interventional culprit plaques of MI group (n = 11) revealed higher SUVmax (P = 0.007) and TBR (P = 0.008) values than culprit CSA plaques. Culprit plaques showed significantly higher SUVmax (P = 0.006) and TBR (P = 0.0003) than non-culprit plaques in MI group, but without significant difference between culprit and non-culprit plaques in CSA group. With median TBR cutoff value of 1.4 in MI culprit plaques, 6/7 plaques (85.7%) among the event prone non-culprit lesions had TBR values > 1.4 in CSA group. CONCLUSION: The study shows higher SUVmax and TBR values in MI culprit plaques and comparable TBR values for event prone plaques of CSA group in identifying high-risk plaques.

Multifocal Extramedullary Relapse With Neuroleukemiosis in a Case of Early T-Cell Precursor ALL: 18F-FDG PET/CT Findings.

ABSTRACT: Early T-cell precursor ALL (acute lymphoblastic leukemia) is a rare type of childhood and adult T-cell ALL. Disease recurrence is common within 2 years from the time of initial diagnosis. Outcomes of relapse have been characterized through risk stratification schemes, and one of the major determinants of overall survival is the overall tumor burden and sites of relapse. Although testicular recurrence is common; Peripheral nerve as a site of recurrence is relatively rare. We present a case of early T-cell ALL on maintenance therapy with multifocal relapse on FDG PET/CT in the cervical lymph nodes, the testis, and the left sciatic nerve. Bone marrow and flow cytometry confirmed the relapse.

Imaging-Guided Use of Combined 177Lu-DOTATATE and Capecitabine Therapy in Metastatic Mediastinal Paraganglioma.

Peptide receptor radionuclide therapy targets highly expressed somatostatin receptors in well-differentiated neuroendocrine tumors, producing stability or a partial response in most patients with inoperable or metastatic disease. However, neuroendocrine tumors showing increased 18F-FDG uptake have limited treatment options and a poor outcome, and the role of peptide receptor radionuclide therapy is still unclear. Here, we present the case of a young man with mediastinal paraganglioma and extensive metastatic disease showing avidity on both somatostatin receptor imaging and 18F-FDG imaging. The patient experienced a partial response to peptide receptor chemoradionuclide therapy (177Lu-DOTATATE and low-dose capecitabine), as well as a significantly improved quality of life. This case highlights the utility of peptide receptor chemoradionuclide therapy when there is extensive disease avid for both somatostatin receptor and 18F-FDG and a lack of other suitable treatment modalities.