Fear of cancer recurrence in long-term colorectal cancer survivors: A randomized controlled trial of a therapist-guided eHealth intervention.

12004 Background: Despite the availability of effective interventions, fear of cancer recurrence (FCR) remains a prevalent and significant concern among cancer survivors, underscoring the need for more accessible and scalable approaches. This trial assessed the effectiveness of a therapist-guided eHealth intervention, TG-iConquerFear. Methods: This parallel randomized controlled trial (ClinicalTrial.org #NCT04287218) enrolled Danish colorectal cancer survivors (CRCS) who had completed curative-intent primary treatment between March 2014 and December 2018, were aged ≥ 18 years, and reported Fear of Cancer Recurrence Inventory-Short Form (FCRI-SF) scores ≥22 (i.e. clinical FCR). After diagnostic interview, eligible participants were randomized to TG-iConquerFear (intervention) or a webpage with self-help mindfulness exercises (augmented control) in a 1:1 ratio. The 10-week TG-iConquerFear program comprised six modules with written therapist guidance delivered asynchronously. Follow-up questionnaires were administered at two weeks (T1), three months (T2), and six months (T3) post-intervention. The primary outcome was predefined as the difference in the change scores of the total FCRI score at T2, analyzed as intention-to-treat. Secondary outcomes were anxiety, depression, emotional distress, health-related quality of life (HrQoL) and physical symptom burden. Pre- and post-intervention mean within and between groups were pairwise compared using Student’s t-test. Results: Of 9,946 eligible CRCS, 5,515 (55.4%) completed FCR screening, and 299 (5.4%) CRCS reported clinically significant FCR (FCRI score ≥ 22). Among them, 221 (73.9%) expressed interested in FCR treatment, and 103 (46.6 %) were randomized to TG-iConquerFear (n = 49) or control (n = 54). Main reasons for non-randomization included new cancer diagnoses or FCR not affecting everyday life. Participants completed 4.5 modules on average, and 55% completed the intervention. Baseline total FCRI score was 84.6/168 in both groups. Total FCRI score decreased more from baseline to T2 in the TG-iConquerFear group (mean -21.7, 95% CI [-30.1, -13.3]) compared to the augmented control group (mean -2.6 95% CI [-7.8, 2.6]). This represents a between-group difference at T2 of 19.1 (95% CI [10.0, 28.3], p < 0.001) corresponding to a standardized effect size (Cohen’s d ) of 0.62 (95% CI [0.13 - 1.1]). A higher proportion of TG-iConquerFear participants were in the non-clinical range at T2 compared to control participants (81.5% vs. 42.9%, p = 0.002). Statistically significant differences favoring the intervention group were observed across all secondary outcomes. Conclusions: The TG-iConquerFear intervention demonstrated a statistical and clinically significant reduction in fear of cancer recurrence in a population of long-term CRCS. The effects were sustained at six months post-intervention. Clinical trial information: NCT04287218 .