RESUMO
PURPOSE: The prognostic evaluation of glioma recurrence patients is important in the therapeutic management. We investigated the prognostic value of 11C-methionine PET-CT (MET-PET) dynamic and semiquantitative parameters in patients with suspected glioma recurrence. METHODS: Sixty-seven consecutive patients who underwent MET-PET for suspected glioma recurrence at MR were retrospectively included. Twenty-one patients underwent static MET-PET; 46/67 underwent dynamic MET-PET. In all patients, SUVmax, SUVmean and tumour-to-background ratio (T/B) were calculated. From dynamic acquisition, the shape and slope of time-activity curves, time-to-peak and its SUVmax (SUVmaxTTP) were extrapolated. The prognostic value of PET parameters on progression-free (PFS) and overall survival (OS) was evaluated using Kaplan-Meier survival estimates and Cox regression. RESULTS: The overall median follow-up was 19 months from MET-PET. Recurrence patients (38/67) had higher SUVmax (p = 0.001), SUVmean (p = 0.002) and T/B (p < 0.001); deceased patients (16/67) showed higher SUVmax (p = 0.03), SUVmean (p = 0.03) and T/B (p = 0.006). All static parameters were associated with PFS (all p < 0.001); T/B was associated with OS (p = 0.031). Regarding kinetic analyses, recurrence (27/46) and deceased (14/46) patients had higher SUVmaxTTP (p = 0.02, p = 0.01, respectively). SUVmaxTTP was the only dynamic parameter associated with PFS (p = 0.02) and OS (p = 0.006). At univariate analysis, SUVmax, SUVmean, T/B and SUVmaxTTP were predictive for PFS (all p < 0.05); SUVmaxTTP was predictive for OS (p = 0.02). At multivariate analysis, SUVmaxTTP remained significant for PFS (p = 0.03). CONCLUSION: Semiquantitative parameters and SUVmaxTTP were associated with clinical outcomes in patients with suspected glioma recurrence. Dynamic PET-CT acquisition, with static and kinetic parameters, can be a valuable non-invasive prognostic marker, identifying patients with worse prognosis who require personalised therapy.
RESUMO
BACKGROUND: Hazard classification of chemicals can be defined as a logic-mathematical operation aimed at identifying the type and severity of the inherent hazards of a substance or a mixture. OBJECTIVES: The purpose of this study was to evaluate, in 134 safety data sheets (SDSs): i) the hazard classification and ii) its coherence with sections 9 (physical-chemical properties), 11 (toxicological properties) and 12 (ecological properties) of the SDSs. METHODS: Hazard classification and the information provided in sections 9, 11 and 12 of the SDSs have been evaluated against the criteria provided in annexes VI of the Dangerous Substance Directive, II and III of the Dangerous Preparations Directive, I and VI of the Regulation (EC) n. 1272/2008. RESULTS: Most of the analyzed SDSs of substances (62%) was associated to non-classified chemicals (61.4%), although 19.6% of them should have been classified. By contrast, 59.4% of classified substances (representing 38.6% of analyzed ones) were wrongly classified. Fifty-four %, 54% and 67% of suggested substances hazard classification were in line with sections 9 (physical-chemical properties), 11 (toxicological properties) and 12 (ecological properties). CONCLUSIONS: The proportion of hazard classification mistakes in SDS was significant, suggesting the need of more qualified experts to derive classification. The introduction of an ad hoc evaluation team, managed by a single, qualified specialist, could represent a solution to ensure the needed improvement of SDSs quality.
