The solubility of 5-fluorouracil (5-FU), a widely used chemotherapeutic agent to treat solid tumors, which include colorectal, head and neck, breast, and lung cancer, was determined at temperatures ranging from 278.15 to 333.15 K in 11 pure solvents and binary water + ethanol solvent mixtures using the polythermal method. It was demonstrated that the solubility of 5-FU increases with increasing temperature in the pure solvents and at constant solvent composition in the solvent mixtures. Moreover, the solubility of 5-FU in the solvent mixtures exceeds its solubility in pure water and ethanol. The experimental solubility data of 5-FU in the pure solvents and solvent mixtures were correlated using the modified Apelblat and λh model equations. The predicted solubility data obtained agree with the experimental data based on the calculated relative deviation (RD) and the average relative deviation (ARD%) values. The selected solvents are categorized as either Class 2 or 3 (less toxic and lower risk to human health) solvents, and hence the correlated and experimentally derived solubility data of 5-FU presented provide a pathway to develop and engineer enhanced pharmaceutical processes and products based on this compound.

Purpose: To evaluate the diagnostic accuracy of PET with different radiotracers and parameters in differentiating between true glioma progression (TPR) and post treatment-related change (PTRC).Methods: Studies on using PET to differentiate between TPR and PTRC were screened from the PubMed and Embase databases. By following the PRISMA checklist, the quality assessment of included studies was performed, the true positive and negative values (TP and TN), false positive and negative values (FP and FN), and general characteristics of all the included studies were extracted. Results of PET consistent with reference standard were defined as TP or TN. The pooled sensitivity (Sen), specificity (Spe), and hierarchical summary receiver operating characteristic curves (HSROC) were generated to evaluate the diagnostic accuracy.Results: The 33 included studies had 1,734 patients with 1,811 lesions suspected of glioma recurrence. Fifteen studies tested the accuracy of 18F-FET PET, 12 tested 18F-FDG PET, seven tested 11C-MET PET, and three tested 18F-DOPA PET. 18F-FET PET showed a pooled Sen and Spe of 0.88 (95% CI: 0.80, 0.93) and 0.78 (0.69, 0.85), respectively. In the subgroup analysis of FET-PET, diagnostic accuracy of high-grade gliomas (HGGs) was higher than that of mixed-grade gliomas (Pinteraction = 0.04). 18F-FDG PET showed a pooled Sen and Spe of 0.78 (95% CI: 0.71, 0.83) and 0.87 (0.80, 0.92), the Spe of the HGGs group was lower than that of the low-grade gliomas group (0.82 vs. 0.90, P = 0.02). 11C-MET PET had a pooled Sen and Spe of 0.92 (95% CI: 0.83, 0.96) and 0.78 (0.69, 0.86). 18F-DOPA PET had a pooled Sen and Spe of 0.85 (95% CI: 0.80, 0.89) and 0.70 (0.60, 0.79). FET-PET combined with MRI had a pooled Sen and Spe of 0.88 (95% CI: 0.78, 0.94) and 0.76 (0.57, 0.88). Multi-parameters analysis of FET-PET had pooled Sen and Spe values of 0.88 (95% CI: 0.81, 0.92) and 0.79 (0.63, 0.89).Conclusion: PET has a moderate diagnostic accuracy in differentiating between TPR and PTRC. The high Sen of amino acid PET and high Spe of FDG-PET suggest that the combination of commonly used FET-PET and FDG-PET may be more accurate and promising, especially for low-grade glioma.