Purpose or Case Report: In Li-Fraumeni Syndrome (LFS), early metabolic alterations can precede the structural evidence of cancer. This creates an important opportunity for PET-CT to detect tumors earlier than conventional imaging alone. Our objective was to illustrate the predictive value of serial PET-CT for early tumor detection in Trp53 mutant mice, using a representative case study.
Methods & Materials: Homozygous Trp53 mutant mice underwent baseline PET/CT at 2 months of age, followed by monthly surveillance scans. PET/CT metrics, including SUVmax and 3D localization, were used to identify metabolic hotspots. MRI was performed for anatomical correlation after a hotspot was detected. All suspected tumors were confirmed with terminal histopathology.
Results: In Mouse 1307, serial PET/CT revealed focal bowel metabolic activity (SUVmax 8.6) prior to any overt clinical signs. 3D PET/CT analysis precisely localized this hotspot, guiding subsequent MRI evaluation. MRI confirmed rapid tumor growth, with volumes increasing from 1293 mm^3 to 5194 mm^3 over a one-month period.
Conclusions: This case demonstrates that serial PET/CT can identify early metabolic signatures of tumor development in Trp53 mutant mice, enabling targeted MRI confirmation and timely intervention. This suggests PET/CT could serve as a minimally invasive biomarker to improve surveillance strategies for high-risk pediatric LFS patients.