Relationship between distressing cancer-related recollections and hippocampal volume in cancer survivors

Objective: Having cancer is extremely stressful, and distressing cancer-related recollections are frequently reported by cancer survivors. Smaller hippocampal volume has been observed in stress-related neuropsychiatric disorders, such as posttraumatic stress disorder (PTSD) and major depression. The aim of this study was to determine whether there is a similar association between distressing cancer-related recollections and hippocampal volume. Method: The subjects were 67 women who had had breast cancer surgery 3 or more years earlier and had no history of PTSD or major depression before the cancer. Each woman was evaluated with a semistructured interview to determine whether she had a history of distressing cancer-related recollections. Hippocampal volume was measured by three-dimensional magnetic resonance imaging, and memory function was assessed by the Wechsler Memory Scale - Revised. Results: The volume of the left hippocampus was significantly smaller (5%) in the subjects with a history of distressing cancer-related recollections (N=28) than in those without any such history (N=39). There was no significant difference in right hippocampal volume or whole brain volume measured as a control. There were no significant differences in delayed memory or percentage retention. However, significantly worse immediate visual memory, but not verbal memory, was observed in the subjects with a history of distressing cancer-related recollections. Conclusions: Having distressing cancer-related recollections is associated with smaller left hippocampal volume in survivors of breast cancer.