The psychosomatic symptoms of patients with differentiated thyroid cancer (DTC) during the initial treatment phase need to be improved. Stress coping training aims to reshape an individual's perception of stress and provide skill training, thereby influencing how they cope in stressful situations. Symptom management theory emphasizes improving health outcomes by helping individuals perceive and manage their symptoms.

Therefore, this clinical trial combines stress coping training and symptom management theory to construct and test an intervention program for psychosomatic symptoms in DTC patients. The main questions it aims to answer are:

• Does the psychosomatic symptom intervention alleviate participants' levels of anxiety and depression?
• Does the psychosomatic symptom intervention promote participants' achievement of TSH suppression therapy standards?
• Does the psychosomatic symptom intervention enhance participants' self-management efficacy?
• Does the psychosomatic symptom intervention improve participants' shoulder joint function?

Researchers will compare the psychosomatic symptom intervention with continuous psychological care (a form of comforting care) to determine if the intervention better promotes participants' psychosomatic health.

1. Before conducting this clinical trial, researchers conducted qualitative interviews with DTC patients and healthcare providers, followed by literature analysis and expert consultations to develop a psychosomatic symptom intervention program for DTC patients during the initial treatment phase.
2. A total of 84 DTC patients in the initial treatment phase were recruited and randomly grouped into two blocks. The intervention group received a 12-week psychosomatic symptom intervention in addition to routine care, while the control group received 12 weeks of continuous care. Data were collected before the intervention, at the end of the intervention, 3 months after the intervention, and 6 months after the intervention.

The psychosomatic symptom intervention mainly includes:

• Psychological module: symptom logs, meditation, positive psychology, and emotional management
• Physiological module: gargling exercises, "T" exercises, "米" exercises, and shoulder-neck exercises
• The psychosomatic module aims to intervene at three levels: individual, environmental, and health and disease. The individual level includes role management and self-awareness. The environmental level includes resource utilization, family support, peer support, and social support. The health and disease level includes disease management, individual counseling, and progressive muscle relaxation training.
• The intervention is divided into three stages: concept formation, skill acquisition and repetition, and application and completion. These stages are further divided into six sub-stages, each containing content from the psychological, physiological, and psychosomatic modules.

Inclusion criteria:

1. Clinical diagnosis of differentiated thyroid cancer
2. Participants had to be in the initial treatment phase
3. Cognitive and communication skills are normal
4. Can use a smartphone
5. Voluntary participation in the study

Exclusion criteria:

1. History of neck or shoulder trauma
2. Coexisting serious heart, brain, or lung diseases
3. History of a major psychological disorder or mental illness
4. Patients taking hypnotics or psychotropic medications
5. have recently participated in a similar intervention or are receiving other psychotherapy