Safety and Efficacy of SBRT in the Reirradiation for Ultra-central Thoracic Malignant Tumors

Inclusion Criteria

• •Pathological diagnosis is malignant tumor.
• •The location of the target lesion belongs to the ultra-central type of chest.
• •The target lesion had a history of radiotherapy, and the lesion diameter is ≤ 5cm.
• •There is no extensive systemic metastasis or although there is metastasis, the metastasis have been controlled by previous treatment.
• •KPS\>70, no serious or uncontrolled underlying diseases, such as severe or uncontrolled hypertension, diabetes, cardiovascular and cerebrovascular diseases and organ dysfunction, and patients are expected to be tolerated by radiotherapy.