OLIGO-10: Stereotactic Ablative Radiation Therapy for Metastatic Patients With 6 to 10 Metastatic Sites

1. A patient with a previously verified diagnosis of a malignant neoplasm of any localization (ICD 10-11 codes C) who meets the inclusion criteria, after approval by the tumor board for the study group, will undergo the following procedures:

Three-dimensional/four-dimensional computed tomography for simulation using specialized fixation devices (the choice of the CT method and fixation devices will depend on the location of the metastasis).

The resulting images will be added to the contouring program.

Delineation of targets and organs at risk will be performed.

Clinical volumes and error margins will be determined. 2. The total dose per target and dose limits for critical structures will be prescribed.

Dosimetric planning for the course of external beam radiation therapy will be carried out.

Irradiation sessions will be conducted on a linear accelerator with a multi-leaf collimator, including a function for visual control of the target using cone beam tomography with kilo-voltage/mega-voltage radiation.

When the target is localized in the lungs, liver, or adrenal glands, to reduce the radiation load on surrounding healthy tissues and achieve necessary control over the position of the metastasis, irradiation will be performed with a deep breath hold or at specific phases of respiration. 3. Tumor Localization / Description / Total Focal Dose (Gy) / Number of Fractions / Single Focal Dose (Gy) / Irradiation Mode:

Lung Tumors:

Tumors ≤ 3 cm located in the parenchyma: TD 45 Gy in 3 fractions with 15 Gy each day Tumors adjacent to the chest wall or \< 3 cm: TD 50 Gy in 5 fractions with 10 Gy each day Tumors within 2 cm of the mediastinum or brachial plexus: TD 60 Gy in 8 fractions with 7.5 Gy each day Bones: TD 24 Gy in 3 fractions with 8 Gy each day

Brain Metastases:

Tumor volume from 0.5 to 5 cm³: TD 20-22 Gy in 1 fraction at a time Tumor volume from 5 to 10 cm³: TD 16-18 Gy or TD 18-20 Gy in 1 fraction at a time Liver: Radiation regimen selection based on the tolerance of surrounding tissues and proximity to critical structures: TD 30-60 Gy in 3-8 fractions with 6-15 Gy each day

Adrenal Glands: TD 60 Gy in 8 fractions with 7.5 Gy each day 4. Expected Duration of Patient Participation in Clinical Testing:

Pre-hospital period: Comprehensive examination of the patient before treatment. Inpatient period: Includes pre-radiation preparation for up to 3 working days, SABR treatment for 1 to 8 working days.

Follow-up period: 3, 6, 9, and 12 months post-treatment; thereafter, follow-up will occur every 6 months up to 60 months.

Collection and processing of received data.

• Effectiveness (PFS) [Срок оценки: From the date of initiation until the date of documented disease progression, assessed over a period of up to 60 months.]
• Effectiveness (LC) [Срок оценки: From the date of initiation until the date of documented radiological signs of metastasis relapse, assessed over a period of up to 60 months.]
• Effectiveness (OS) [Срок оценки: From the date of initiation until the date of death from any cause, assessed over a period of up to 60 months.]
• Time-to-CTX-change [Срок оценки: End of years 1, 2, 3, 4, 5 (study completion)]