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

Study Overview
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Brief Summary
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The reirradiation of thoracic tumor is difficult. The possibility of surgery or re course radiotherapy is very small. In the NCCN guideline, only systemic treatment is recommended. However, the effective rate of systemic treatment is low. SBRT has the characteristics of high dose in tumor target area and low dose in surrounding normal tissues. In theory, SBRT is more conducive to the protection of normal tissues and can potentially be used in the salvage treatment of recurrent lesions after radiotherapy. Even so, SBRT is still controversial in the rescue treatment of recurrent lung cancer after radiotherapy, especially for ultral-central lesions close to mediastinal structures (such as bronchus, esophagus and large blood vessels), which have a high probability of fatal side effects. However, a few studies on the application of SBRT in the reirradiation for ultral-central lung cancer have shown acceptable safety and efficacy. Generally speaking, there are few studies on SBRT in the treatment of recurrent ultral-central tumor with limited data. The purpose of this study is to further evaluate the efficacy and toxicities of SBRT in the treatment of recurrent ultral-central tumors after radiotherapy.

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

Conditions
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Stereotactic Body Radiation Therapy, Irradiation; Reaction, Thoracic Tumor, Recurrent Cancer

Intervention / Treatment
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* Radiation: stereotacitic body radiation therapy


Participation Criteria
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Eligibility Criteria
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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. Exclusion Criteria: Poor basic pulmonary function or symptom correlation caused by various reasons, unable to lie flat or cooperate with treatment. The general condition is poor, and the expected survival time is less than 3 months. Psychiatric patients or poor compliance, unable to cooperate to complete treatment. For other reasons, the researcher believes that it is not suitable to participate in this trial.

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 80 Years

Sexes Eligible for Study
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All

Study Plan
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How is the study designed?
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Arms and Interventions

| Intervention/Treatment |
| --- |
|Radiation: stereotacitic body radiation therapy|The patients were treated with high-dose and low fractionated radiotherapy, using modern precision radiotherapy technology.|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Toxcicties | Adverse events of radiation of normal tissues (Including lung, trachea, bronchus, esophagus, blood vessels, ribs, spinal cord, brachial plexus). | From the beginning of the treatment to 3 years after the treatment. | 
| Local control time | The time from the date of SBRT to the date of recurrence of the target tumor or the date of last observation. | From the beginning of the treatment to 3 years after the treatment. | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Overall survival time | The time from the date of SBRT to the date of death from any cause or the date of last observation. | From the beginning of the treatment to 3 years after the treatment. | 
| Disease progression time | The time from the date of SBRT to the date of disease progression from any cause or the date of last observation. | From the beginning of the treatment to 3 years after the treatment. |