APOE and Mental deterioration: Methods: Patient C.S. is a 74-year old female with a 5-year history of cognitive decline who was placed on DFMO (500 mg b.i.d.)for 12 months, with amyloid PET scans (baseline and 12-months), APOE genotyping and neuropsychological exams at baseline, 3, 9, and 12 months.