Hippocampal Memory Impairment In Breast Cancer Survivors After Chemotherapy Measurement Using Covert Testing

1024 Background: Cognitive impairments are frequently reported following adjuvant chemotherapy, yet potential neuropathological substrates remain uncertain. Chemotherapy and anti-estrogen therapy have neurotoxic effects in rodent models, with disproportionate impairment of the structure and function of the hippocampus, a critical structure for long-term declarative and relational memory. To date, there have been no detailed assessments of human hippocampal function following adjuvant chemotherapy. Methods: We used a specialized test of covert long-term memory processing sensitive to hippocampal impairment, involving eye-movement tracking coupled with functional MRI (fMRI). We compared 13 premenopausal breast cancer survivors on tamoxifen who were within 18 months of completing adjuvant chemotherapy to 14 healthy controls. Results: Relative to controls, patients were not impaired on standard delayed overt recognition memory testing or on neuropsychological tests. In contrast, patients were impaired in eye-...