Approximately 25% of those who are diagnosed with colorectal cancer will develop colorectal liver metastases (CRLM) as their illness advances. Despite major improvements in both diagnostic and treatment methods, the prognosis for patients with CRLM is still poor, with low survival rates. Accurate employment of imaging methods is critical in identifying the most effective treatment approach for CRLM. Different imaging modalities are used to evaluate CRLM, including positron emission tomography (PET)/computed tomography (CT). Among the PET radiotracers, fluoro-18-deoxyglucose (18F-FDG), a glucose analog, is commonly used as the primary radiotracer in assessment of CRLM. As the importance of 18F-FDG-PET/CT continues to grow in assessment of CRLM, developing a comprehensive understanding of this subject becomes imperative for healthcare professionals from diverse disciplines. The primary aim of this article is to offer a simplified and comprehensive explanation of PET/CT in the evaluation of CRLM, with a deliberate effort to minimize the use of technical nuclear medicine terminology. This approach intends to provide various healthcare professionals and researchers with a thorough understanding of the subject matter.

UNASSIGNED: Neuroblastoma is a solid malignant tumor with high malignancy and high risk for metastasis. The prognosis of neuroblastoma ranges from spontaneous regression to insensitivity to therapies and widespread metastasis. There is a non-invasive, panoramic imaging technique called 18F-fluorodeoxyglucose (18F-FDG) positron emission tomography-computed tomography (PET/CT), which can provide both complete anatomical information via CT and extent of FDG uptake value in tumors via positron emission detection. PET/CT is a powerful approach to estimating tumoral metabolic activities, and PET/CT parameters have been demonstrated to be associated with the prognosis of various tumors. However, the predictive performance of PET/CT for the prognosis of neuroblastoma remains unclear. This meta-analysis aims to assess the predictive values of maximum standardized uptake value (SUVmax), metabolic tumor volume (MTV), and total lesion glycolysis (TLG) for progression-free survival (PFS), event-free survival (EFS), and overall survival (OS) in neuroblastoma patients.
UNASSIGNED: Literature in PubMed, Embase, Cochrane Library, and Web of Science from January 1985 to June 2023 was searched for studies evaluating predictive values of PET/CT parameters for the prognosis of neuroblastoma. Search items mainly included \"Positron Emission Tomography Computed Tomography\" and \"Neuroblastoma\". Hazard ratio (HR) was used as a pooled statistic to assess the association of SUVmax, MTV, and TLG with PFS, EFS, and OS in neuroblastoma patients. Heterogeneity test and sensitivity analysis were performed.
UNASSIGNED: There were eight studies included, with 325 participants. Meta-analysis showed that higher SUVmax was associated with shorter OS [HR = 1.27, 95% CI (1.11, 1.45), p = 0.001], while no association with PFS [HR = 1.03, 95% CI (0.99, 1.07), p = 0.222] and EFS [HR = 2.58, 95% CI (0.37, 18.24), p = 0.341] was presented. MTV showed no association with OS [HR = 2.46, 95% CI (0.34, 18.06), p = 0.376] and PFS [HR = 2.60, 95% CI (0.68, 9.88), p = 0.161]. There was a statistically significant association between TLG and OS [HR = 1.00, 95% CI (1.00, 1.00), p = 0.00], while the HR was 1, so the association could not be concluded, and TLG showed no association with PFS [HR = 1.00, 95% CI (0.99, 1.00), p = 0.974].
UNASSIGNED: High SUVmax indicates poor OS in patients with neuroblastoma. The MTV and TLG are potential prognostic predictors that need to be further validated by more well-designed studies.
UNASSIGNED: https://www.crd.york.ac.uk/PROSPERO/, identifier 340729.

IgG4-related disease (IgG4-RD) is a systemic fibro-inflammatory disease, histopathologically characterized by dense lymphoplasmacytic infiltration rich in IgG4-positive plasma cells in affected organs. Classic hematologic presentations including lymphadenopathy, eosinophilia and polyclonal hypergammaglobulinemia are common, whereas bone marrow involvement of IgG4-RD is rarely reported. Here we present two patients of multi-organ IgG4-RD with bone marrow involvement, one on bone marrow biopsy, and the other on PET/CT. Presentations of other organ involvement included biopsy-proven IgG4-related tubulointerstitial nephritis, lymphadenopathies, submaxillary glands, arteritis, asthma, dysosmia, and constitutional symptoms. Bone marrow involvement was initially suspected due to leukopenia, anemia and thrombocytopenia in case#1, and was finally confirmed by histological evidence of significant IgG4-positive plasma cells infiltration in bone marrow. In case#2, we incidentally observed high uptakes of multi-bone marrow on 18F-FDG-PET/CT, with the maximum SUV value similar to that of the kidneys, submaxillary glands and hilar, mediastinal lymph nodes by 18F-FDG-PET/CT. Symptoms and all the hematologic presentation improved rapidly in both patients after steroids initiation. These two cases illustrate the rare bone marrow involvement in active IgG4-RD accompanied by other hematologic syndromes. The significance of disease pathogenesis is worthy of further study.

Ocular sebaceous adenocarcinoma is a rare malignant tumor. We report an unusual case of orbital sebaceous adenocarcinoma in a 48-year-old woman. The patient underwent F-18 2-fluoro-2-deoxy-glucose positron emission tomography/computed tomography ((18)F-FDG-PET/CT) to determine the initial clinical stage. (18)F-FDG-PET/CT showed strong uptake in the orbital lesion, but neither regional lymphatic nor distant metastases were seen. (18)F-FDG-PET/CT plays a role in the diagnosis, staging, restaging, and follow-up of ocular sebaceous carcinoma, although its application has some limitations in other primary and ocular malignancies due to the rarity of ocular sebaceous carcinoma.

A 38-year-old female was found to have multiple bilateral lung nodules in a routine chest X-ray examination. Thoracoscopy was performed with biopsy of three nodules from the right lower lobe and Congo red staining showed typical amyloid pattern. Initial diagnosis of pulmonary nodular amyloidosis was made. However, one nodule in the right upper lobe enlarged as detected by follow-up CT scan. The patient underwent F-18 fluorodeoxyglucose positron emission tomography ((18)F-FDG-PET)/CT and a significant high FDG uptake in the largest nodule in right upper lobe was observed while the uptake was normal or mildly increased in the other nodules. Meanwhile, right hilar and mediastinal lymph nodes adenopathy was noted. Right upper lobe was resected by thoracotomy. Surprisingly, histopathological findings showed pulmonary epithelioid hemangioendothelioma (PEH) with metastasis of hilar and mediastinal lymph nodes. To our knowledge, this is the first described case of PEH coexisting with pulmonary nodular amyloidosis.