Assessing cognitive dysfunction in breast cancer: what are the tools?

The goal of adjuvant chemotherapy in the treatment of breast cancer is to reduce recurrence and mortality. With respect to quality of life and morbidity, however, such treatments come at a cost. Decreased cognitive functioning, development of fatigue, and mood alterations are common during chemotherapy and persist after its conclusion as evidenced by subjective self-reports and objective neurocognitive performance records. Few efforts, however, have used standardized neuropsychological measures, and no study has empirically selected those measures that best distinguish women in active chemotherapy from those who have previously completed it. Perhaps the most glaring deficit in the literature is that no study has used baseline data to track individual neurocognitive changes across treatment phases and after completion. This article provides an overview of the field of neuropsychology and the cognitive domains theorized to be affected by chemotherapy and the measures typically used, including validated computerized tests, which are tools for future studies; briefly summarizes existing research on the cognitive effects that chemotherapy has on breast cancer patients; compares data resulting from an ongoing pilot study of the cognitive performance of women actively undergoing anthracycline-containing chemotherapy with that of women 6-12 months post chemotherapy completion; and provides a preliminary analysis of the relationship between cognitive and emotional functioning. Future uses of these data to refine the ideal tools that efficiently, accurately, and validly detect short-term and persistent chemotherapy effects are proposed.