Systemic Therapy Alone or With Stereotactic Body Radiotherapy for Oligometastatic Kidney Cancer (STROKER Study)

PRIMARY OBJECTIVES:

To compare the progression-free survival (PFS) between patients receiving SBRT + standard systemic therapy versus standard systemic therapy alone.

SECONDARY OBJECTIVES:

I. To compare the overall survival (OS) between patients receiving SBRT + standard systemic therapy versus standard systemic therapy alone.

II. To compare the cancer specific survival (CSS) between patients receiving SBRT + standard systemic therapy versus standard systemic therapy alone.

III. To estimate the local control (LC) rate of SBRT. IV. To compare the post-treatment progression-free survival (post-treatment PFS) between patients receiving SBRT + standard systemic therapy versus standard systemic therapy alone.

V. To evaluate treatment-related toxicity after adding SBRT based on patient-reported outcomes and researcher reported adverse events.

VI. To compare the quality of life between patients treated with SBRT or not using EQ-5D-5L, FKSI-DRS and FKSI-19.

OUTLINE: Patients are randomized to either Control arm or SBRT arm.

Control arm: Patients receive standard of care systemic therapy on study. SBRT arm: Patients undergo SBRT to all metastatic sites in addition to standard of care systemic therapy on study.

Patients periodically receive computed tomography (CT), positron emission tomography (PET)/CT, and/or magnetic resonance imaging (MRI) throughout the trial.

Inclusion criteria

• Pathologically confirmed diagnosis of renal cell carcinoma of any histology
• Age ≥ 18 years.
• ECOG performance status of 0-2.
• Imaging suggests the presence of distant metastases, with no more than 5 metastatic lesions according to RECIST 1.1 criteria and MDA standards.
• The patient has received local therapy to primary site, including surgery, stereotactic radiotherapy, or ablation.
• The patient has received no more than 2 lines of systemic therapy.
• No significant impairment of major organ function:

Hemoglobin (HB) ≥ 80 g/L Absolute neutrophil count (ANC) ≥ 1.5 × 10⁹/L Platelets (PLT) ≥ 75 × 10⁹/L Serum total bilirubin ≤ 1.5 × ULN Alanine aminotransferase (ALT) and aspartate aminotransferase (AST) ≤ 3 × ULN Prothrombin time (PT) and activated partial thromboplastin time (aPTT) ≤ 1.5 × ULN

Exclusion criteria

• Presence of intracranial metastases.
• Target lesions have previously received high-dose irradiation with .
• Target lesions are unsuitable for radiation therapy judged by treating radiation oncologist (e.g., lesions invading the gastrointestinal tract or penetrating the bronchus).
• Uncontrollable metastatic pleural effusion or ascites.
• Presence of other malignancies that have not been cured.
• History of significant psychiatric disorders that impede understanding of informed consent and compliance with the study protocol.
• Presence of other serious illnesses that may pose significant risks or affect radiation therapy.
• Women who are pregnant, breastfeeding, or with plans for childbearing during the study.
• Any other reasons deemed by the investigator to make the subject unsuitable for participation in the study.