A Systematic Review and Meta-Analysis on the Diagnostic and Prognostic Values of 18 F-FDG PET in Uveal Melanoma and Its Hepatic Metastasis.

In this systematic review and meta-analysis (PRISMA-compliant), we tried to investigate diagnostic and prognostic values of 18 F-FDG PET in uveal melanoma. A systematic search was conducted on the main medical literature databases to include studies that evaluated 18 F-FDG PET as the imaging modality to evaluate patients with uveal melanoma. Overall, 27 studies were included. Twelve had data about the detection rate of 18 F-FDG PET in primary intra-ocular tumours. The pooled sensitivity was 45% (95%CI: 41-50%). Furthermore, studies showed that the larger the primary tumour, the higher its uptake. Among the included studies, 13 assessed 18 F-FDG PET in detecting metastasis. The pooled sensitivity and specificity were 96% (95%CI: 81-99%) and 100% (95%CI: 94-100%), respectively. Regarding liver metastasis, they were 95% (95%CI: 79-99%) and 100% (95%CI: 91-100%), respectively. Noteworthy, the level of 18 F-FDG uptake was a strong predictor of patient survival. Lastly, 18 F-FDG PET could characterise lesions from the histopathology perspective, distinguishing high-risk from low-risk diseases. Overall, although not reliable in detecting primary intra-ocular tumours, 18 F-FDG PET is highly accurate for diagnosing metastatic uveal melanomas. It can also be a highly valuable modality in terms of patient prognostication. Thus, 18 F-FDG PET can be recommended in patients diagnosed with uveal melanoma to enhance decision-making and patient management.