The Validation of ICBT Clinical Trial: Disease Stress Adjustment in Breast Cancer Patients

Breast cancer and its treatment can cause ongoing emotional distress, including anxiety, depressive symptoms, stress-related reactions, and difficulties adjusting to life after treatment. This study evaluates an 8-week Internet-based cognitive behavioral therapy (ICBT) program designed to support psychological adjustment and improve quality of life among adults with stage I-III breast cancer who have completed primary cancer treatment. Approximately 100 participants will be randomly assigned to either an ICBT group or a control group. Participants in the ICBT group will receive treatment as usual together with the 8-week online program, while participants in the control group will receive treatment as usual alone during the main study period. The study will compare changes in anxiety, depressive symptoms, post-traumatic stress symptoms, and quality of life between the two groups.

Inclusion Criteria: * Adults aged 18-65 years. * Diagnosis of stage I-III breast cancer. * Completion of primary breast cancer treatment, including surgery, chemotherapy, radiation therapy, and/or targeted therapy. Participants currently receiving endocrine therapy are eligible. * Ability to read and write Chinese and to use a mobile application and the Internet. * Access to an Internet-enabled device and ability to independently participate in the online intervention. * Willingness to complete the online intervention modules and study assessment questionnaires. Exclusion Criteria: * Diagnosis of stage IV breast cancer. * Concurrent diagnosis of another type of cancer. * Currently receiving surgery, chemotherapy, radiation therapy, or targeted therapy for breast cancer. * Diagnosis of a psychiatric disorder within the past 6 months, including major depressive disorder, generalized anxiety disorder, or schizophrenia. * No current psychiatric diagnosis but a Patient Health Questionnaire-9 (PHQ-9) score greater than 20 at screening. * Current suicidal intent or a history of actual self-harm behavior. * Currently receiving another form of psychotherapy or having recently received cognitive behavioral therapy. * Inability to independently use the online intervention application because of insufficient Chinese literacy, Internet proficiency, or access to an Internet-enabled device.