Neurocognitive Functioning in Metastatic Cancer Survivors Treated With Immune Checkpoint Blockade: First Results of A Single Center Cohort Study

Background: Cancer survivors treated with immune checkpoint blockade (ICB) may be at risk of experiencing neurocognitive impairment (NCI) (Rogiers et al., 2020).Methods: Patients with unresectable AJCC Stage III/IV cancer of any type, who initiated ICB ≥1y ago and achieved complete remission, were eligible for this ongoing study. Neurocognitive functioning was assessed using the test battery COGBAT and the Corsi Block Tapping Test. Neurocognitive impairment was defined by the International Cancer and Cognition Taskforce guidelines and deficits per subtest as ≤ -1,5SD. Subjective cognition and fear of cancer recurrence (FCR) were retrieved through the Cognitive Failure Questionnaire and the FCR-Inventory-Short-Form.Results: Between 07/2022 and 10/2022, 35 patients were recruited (22M/13F). Median age was 61y[44-92]; median time since complete remission was 3.3y[0.3-9.3]; all but 1 electively discontinued ICB; median time since last ICB administration was 3.9y[0.0-9.3]. Thirty-one survivors had been diagnosed with melanoma, 3 with non-small cell lung carcinoma, 1 with bladder cancer. Nine patients had a history of brain metastasis. A majority (N=20, 57%) had NCI, of whom 4 had a prior history of brain metastasis. Cognitive deficits were predominately observed in processing speed (N=14, 40%) and memory (learning ability, N=14, 40%; visual recognition, N=12, 34%; long-term recall, N=11, 31%; short-term recall, N=10, 29%; visuospatial memory span, N=3, 9%). In a lesser amount, deficits were detected in executive function (working memory, N=6, 17%; cognitive flexibility, N=5, 14%; inhibition, N=4, 11%; planning, N=3, 9%) and attention (alertness, N=4, 11%; divided attention, N=3, 9%). Age was the only significant predictor for the degree of objective cognitive function (β=.-726, p<.001). Seven survivors (20%) reported subjective NCI, of whom 2 had objective NCI. Twenty-one survivors (60%) had significant to pathological FCR. Conclusions: A majority of the cancer survivors treated with ICB have objective neurocognitive impairment and suffer from clinically relevant FCR.