The chemo-brain effect in colorectal cancer patients.

Abstract

e24095 Background: The chemo-brain effect associated with systemic chemotherapy results in cognitive disturbances impacting the capacity to engage in tasks and quality of life (QOL). Patients with colorectal cancer (CRC) who receive adjuvant chemotherapy generally have long survival times. The long-term effect of chemotherapy on cognition is uncertain. We aimed to ascertain the frequency of long-term cognitive impairment using neuropsychological assessments and correlating with neuroimaging. Methods: In this prospective pilot study, patients (n=22) with stage II to III CRC between 45 to 75 years old, who were planned to receive adjuvant chemotherapy, were recruited. 3 visits were scheduled for each subject – pre-chemotherapy (V1), at 1 month post chemotherapy (V2), and at 6 months post chemotherapy (V3). Serial tests were performed – the Cambridge Neuropsychological Test Automated Battery (CANTAB), QOL questionnaires (Hospital Anxiety and Depression Scale (HADS), Perceived Deficits Questionnaire (PDQ), EORTC QLQ-C30, FACT-ES), 3 item pocket smell test, functional PET/MRI brain imaging, and blood biomarker studies. Results: 18/22 subjects (13 male, 5 female) had completed tests at all 3 visits; the median age was 62 years (range 51 – 69). 9/18 had an initial decline (median -0.033) of Rapid Visual Information processing (RVP) at V2; 3/9 showed improvement to baseline at V3. 8/18 had a persistent decline in RVP scores at V3 (median -0.054). This was associated with increased HADS depression scores (mean 3.63 at V2 vs 4.63 at V1), worsening attention scores (mean 4.38 at V3 and 3.63 at V1), prospective memory scores (mean 3.75 at V3 vs 3.38 at V1), and total scores (mean 14.63 at V3 vs 13.75 at V1) on the PDQ. 7/18 had an increase in Paired Associates Learning (PAL) errors (median +6) at V2. 3/7 improved to baseline at V3, while 4/7 continued to have a persistent decline. PAL scores were not associated with worsening retrospective or prospective PDQ memory scores, changes in HADS depression or EORTC QLQ-C30 scores. There was no difference in baseline CANTAB scores for patients reporting declining vs stable QLQ-C30 scores. Conclusions: Only half of patients with initial RVP A and PAL decline improved at 6 months post chemotherapy. Further efforts should be placed to identify those at risk of poor recovery, and develop strategies to manage the chemo-brain effect. The correlation of cognitive decline with neuroimaging will be presented in the final analysis.