Investigation of the Effect of Acceptance and Commitment Therapy-Based Intervention in Oncology Patients

Participants: * They will be randomly divided into three groups (Group 1: ACT, Group 2: Psychoeducation, Group 3: Routine care). * All participants will be asked to complete data collection forms. * Group 1 will participate in a 5-session Acceptance and Commitment Therapy-Based Intervention for Oncology Patients intervention program. * Group 2 will participate in a 5-session Psychoeducation for Oncology Patients program. * During this period, participants in group 3 will continue their routine treatment. * After completion of the interventions, participants will be asked to complete the data collection forms again. * The researchers will then analyze the results and write the report.