Preoperative stereotactic body radiotherapy combined with surgical treatment for renal cell carcinoma and inferior vena cava tumour thrombus: study protocol for a single-arm cohort trial

INTRODUCTION: Although surgery is currently the first choice for patients with renal cell carcinoma and vena cava tumour thrombus, the surgery is difficult, with many complications, and the prognosis of patients is not ideal. Renal cell carcinoma is not sensitive to traditional radiotherapy, but the development of stereotactic ablative body radiotherapy (SABR) technology with the characteristics of high precision, dose and conformity has made the radiotherapy of renal cell carcinoma reexamined. METHODS AND ANALYSIS: STUDY DESIGN: This trial is a single-arm cohort study sponsored by Peking University Third Hospital. STUDY TREATMENT: Preoperative stereotactic ablative radiotherapy combined with surgical treatment. PRIMARY ENDPOINTS: (1) Adverse reactions after 4–6 weeks of SABR. (2) Mayo staging of tumour thrombus. (3) The length of the tumour thrombus from the corresponding anatomical mark. (4) Invasion of the inferior vena cava wall. (5) Recurrent-free survival rate of the tumour. (6) Cancer-specific survival rate. (7) Overall survival rate. (8) Perioperative indicators including operation time, intraoperative bleeding volume and postoperative complications. SECONDARY ENDPOINTS: (1) The longest diameter of the tumour and (2) Lymph node condition. MAIN INCLUSION CRITERIA: Patients with renal cell carcinoma and inferior vena cava tumour thrombus graded from Mayo II to IV and eligible for radical nephrectomy and inferior vena cava thrombectomy. MAIN EXCLUSION CRITERIA: Patients with previous targeted therapy, chemotherapy or other interventions, or who cannot tolerate SABR or surgery. PLANNED SAMPLE SIZE: 20 patients. ETHICS AND DISSEMINATION: The trial protocol and the informed consent of the subjects were submitted and approved by the Peking University Biomedical Ethics Committee. TRIAL REGISTRATION NUMBER: ChiCTR1800015118.