High-Resolution PET Imaging for In Vivo Monitoring of Tumor Response After Photodynamic Therapy in Mice

摘要: The aim of this study was to investigate the use [18F]fluoro-2-deoxy-D-glucose (FDG) and a small-animal PET scanner assess early tumor response after photodynamic therapy (PDT) in mice. PDT consists intravenous administration photosensitizer that accumulates preferentially tissue, followed by local illumination with red light. Two different photosensitizers were used: Photofrin (PII), which has been approved for clinical use, disulfonated aluminum phthalocyanine (AIPcS), is second-generation drug. These drugs have shown induce necrosis through action mechanisms, i.e., mainly initial vascular stasis (PII) or direct cell kill (AIPcS). FDG used follow both perfusion metabolic activity tissue. Methods: performed using mouse model implanted two contralateral murine mammary tumors (5 mm diameter × 2.5 thickness) on back. Only one subjected PDT, whereas other served as control. A total 13 mice studied, 1 without illumination, 3 at 30 min 2 h PII-PDT AIPcS-PDT. Dynamic imaging mice, placed pairs prostate position parallel transaxial planes Sherbrooke animal scanner, bolus injection 11 MBq (300 µCi) FDG. Blood samples collected concurrently from during each an automated microvolumetric blood sampler. Results: Analysis time-activity curves showed (a) scans first provided estimate perfusion, confirmed samples; (b) uptake 15 measurement metabolism clearly demonstrating relative efficacy drugs; (c) tracer concentration interval 3–15 appropriate indicator mechanisms indirect Conclusion: This pilot feasibility dynamic vivo assessing