Internet-Delivered Psychological Treatment for Cancer Survivors

Inclusion Criteria: * Cancer survivor at least 0.5 years after main therapy * Clinically significant anxiety or depression (Patient Health Questionnaire 9 \[PHQ-9\]≥10, or Generalized Anxiety Disorder 7 \[GAD-7\]≥8, or 9-item Fear of Cancer Recurrence Inventory \[FCRI-9\]≥16) * At least 18 years old * Resident of Region Stockholms, Västra Götalandsregionen, or Region Skåne, Sweden (listed and de facto) * Sufficient technical knowledge and knowledge of the Swedish language to take part in a text-based online treatment * Continuous access to an electronic device that can be used to access the study web platform Exclusion Criteria: * Recurrent thoughts of suicide, as based on clinical judgement aided by the structured interview and the self-report version of the Montgomery-Åsberg Depression Rating Scale (MADRS-S) item 9 * Severe medical condition (e.g., very poor prognosis, stage IV cancer), severe psychiatric disorder (e.g., psychotic disorder, bipolar disorder, or severely debilitating substance use disorder, severe depression), or medical treatment (e.g., chemotherapy, immunotherapy, radiotherapy) that makes the treatment unfeasible * Other ongoing psychological treatment * Continuous psychotropic medication not stable for the past 4 weeks, or not expected to remain stable during the treatment period * Planned absence for more than one week of the intended treatment period * No complete the pre-treatment assessment