The causal link between chemotherapy and cognitive impairment is unclear. We studied testicular cancer patients’ objective and subjective cognitive function longitudinally, comparing a surgery group with a surgery + chemotherapy group, addressing prior methodological issues using a computerized test to limit assessment issues, and controlling for confounding variables.
Prospectively, of 145 patients from 16 centres with sufficient data, n = 61 receiving surgery + chemotherapy (etoposide and cisplatin ± bleomycin, BEP/EP; or single agent carboplatin) were compared to n = 41 receiving surgery alone. CogHealth assessed six objective cognitive tasks. The Cognitive Failures Questionnaire assessed self-perceived cognitive dysfunction. The Functional Assessment of Chronic Illness Therapy-Fatigue and the Hospital Anxiety and Depression Scale assessed psychological influences. Linear mixed models compared changes from baseline (< 6 months post-surgery/pre-chemotherapy) to follow-up (12-18 months post-baseline), controlling covariates.
There were no significant interaction effects for five objective cognitive function tasks suggesting that changes over time were not due to group membership. However, psychomotor function (controlling for age) and physical well-being were significantly worse for the chemotherapy versus the surgery group at baseline, with groups converging by follow-up. Groups showed no differences in subjective cognitive dysfunction. The chemotherapy group showed higher anxiety, poorer functional well-being and worse fatigue compared to the surgery-only group at baseline, but not by follow-up. For both groups, emotional well-being, functional well-being and anxiety significantly improved over time.
No substantive differences in objective or subjective cognitive dysfunction in either group persisted 12-18 months post-baseline. Patients undergoing chemotherapy for testicular cancer differ from findings in breast cancer populations.