Feasibility and preliminary efficacy of iConquerFear: a self-guided digital intervention for fear of cancer recurrence

Purpose Approximately 50% of cancer survivors experience moderate-severe fear of cancer recurrence (FCR). Self-guided digital interventions have potential to address the high level of FCR-related unmet needs at scale, but existing digital interventions have demonstrated variable engagement and efficacy. This study aimed to evaluate the feasibility and preliminary efficacy of iConquerFear, a five-module self-guided digital FCR intervention. Methods Eligible curatively treated breast cancer survivors were recruited. Participants reporting clinically significant FCR (≥ 13 on the Fear of Cancer Recurrence Inventory-Short Form; FCRI-SF) were given access to iConquerFear. Feasibility was indicated by > 50% of eligible participants enrolling in iConquerFear and recording moderate (≥ 120 min) or greater usage. Preliminary efficacy was evaluated via changes in self-reported FCR severity, anxiety, depression, intrusions and metacognitions from baseline to immediately and 3 months post-intervention. Results Fifty-four (83%) of 65 eligible participants enrolled in iConquerFear; six subsequently withdrew. Thirty-nine (83%) participants recorded moderate ( n = 24; 120–599 min) or high ( n = 15; ≥ 600 min) usage. Engagement levels increased with participant age ( p = 0.043), but were lower in participants with higher baseline FCR ( p = 0.028). Qualitative feedback indicated engagement was sometimes limited by difficulties with navigation and relating to featured survivors. Participants reported significantly improved FCR (mean reduction (95%CI): baseline to post-intervention − 3.44 (− 5.18, − 1.71), baseline to 3-month follow-up − 4.52 (− 6.25, − 2.78), p = < 0.001). Conclusion iConquerFear is a feasible and potentially efficacious intervention for reducing FCR in breast cancer survivors. Easier navigation and more relatable examples may enhance engagement. Implications for Cancer Survivors iConquerFear may help address moderate but burdensome FCR levels in cancer survivors.