A Prospective, Single-Center, Single-Arm, Phase II Clinical Study of Stereotactic Ablative Radiotherapy Combined With Axitinib and Toripalimab in the Treatment of Oligometastatic Clear Cell Renal Cell Carcinoma
This is a phase II clinical trial testing whether a combination of stereotactic ablative radiotherapy (SABR), axitinib, and toripalimab is effective and safe for treating oligometastatic clear cell renal cell carcinoma (a type of kidney cancer that has spread to 5 or fewer sites). In this study, all metastatic tumors will be treated with SABR - a precise, high-dose radiation therapy delivered in 5 sessions. At the same time, participants will receive axitinib (an oral targeted cancer drug) twice daily, and toripalimab (an intravenous immunotherapy) every 3 weeks for up to 2 years. The study will enroll 48 participants. The main goal is to measure the objective response rate - the proportion of patients whose tumors shrink or disappear after treatment. Researchers will also track how long patients live without their cancer worsening, overall survival, and any side effects from the treatment. Participants will have regular imaging scans, blood tests, and quality-of-life assessments throughout the treatment and follow-up period.
• Histologically confirmed diagnosis of clear cell renal cell carcinoma (ccRCC).
• Age ≥ 18 years.
• Eastern Cooperative Oncology Group (ECOG) performance status of 0-2.
• Radiological evidence of distant metastasis meeting the MD Anderson (MDA) definition of oligometastatic disease: ≤5 metastatic lesions, all amenable to curative-intent local therapy. Lesions must be measurable per RECIST 1.1 criteria.
• Prior definitive local therapy to the primary tumor, including surgery, stereotactic radiotherapy, or ablation.
• Either no prior systemic therapy for metastatic disease (first-line naïve), or prior first-line tyrosine kinase inhibitor (TKI) therapy only with subsequent oligoprogression (≤5 progressive lesions with remaining lesions stable).
• Adequate organ function:
• Hemoglobin (Hb) ≥ 80 g/L
• Absolute neutrophil count (ANC) ≥ 1.5 × 10⁹/L
• Platelet count (PLT) ≥ 75 × 10⁹/L
• Serum total bilirubin ≤ 1.5 × upper limit of normal (ULN)
• Alanine aminotransferase (ALT) and aspartate aminotransferase (AST) ≤ 3 × ULN
• Prothrombin time (PT) and activated partial thromboplastin time (aPTT) ≤ 1.5 × ULN
• Voluntary written informed consent obtained, with commitment to complete all treatment and follow-up visits.