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This study compares the dosimetric features and clinical effects of body gamma knife and VMAT radiotherapy for locally advanced primary liver cancer. We retrospectively analyze 20 patients from Chifeng Tumor Hospital who cannot or refuse surgery. For each patient, we will develop both body gamma knife and VMAT radiotherapy plans. Then, we'll compare the dose distribution in the tumor target (including conformity index and homogeneity index) and the radiation exposure to organs at risk (such as the spinal cord, stomach, and liver). The goal is to find out which radiotherapy approach is more beneficial, so patients, families, and healthcare teams can better understand how this research supports treatment decisions.

Inclusion Criteria:

• Aged 18-75 years.
• Clinically or pathologically confirmed primary liver cancer; unsuitable for or - refusing surgery, with single tumor diameter ≤5 cm and ≤5 nodules.
• ECOG PS score 0-1.
• Liver function: Child-Pugh grade A or B.
• Prothrombin time (PT) < 4 seconds above the normal control range.
• No hepatic encephalopathy or moderate to large ascites.
• Renal and cardiopulmonary function basically normal.
• Gastroscopy findings: no severe esophageal varices or active peptic ulcer.
• Hemoglobin ≥90 g/L, WBC ≥3.0×10⁹/L, neutrophil ≥1.5×10⁹/L, platelet ≥40×10⁹/L.
• No obvious cachexia; life expectancy > 3 months.
• Not pregnant; no HIV or syphilis infection.
• Able to understand the study and sign informed consent.

Exclusion Criteria:

• History of portal hypertension, esophageal variceal bleeding, or related conditions.
• History of anti-RHCC treatment or spontaneous tumor rupture.
• Postoperative pathology indicates metastatic cancer or other primary cancers.
• Cerebrovascular accident within 6 months before enrollment.
• Severe lung disease; serum creatinine > 1.25×the upper normal limit.
• Poorly controlled acute or active infection; severe mental illness.
• Suspected systemic or local lymphadenopathy on imaging.
• Pregnant or lactating women; presence of other serious underlying diseases.
• Currently participating in other clinical trials; refusal to provide informed consent.

Patients with locally advanced primary liver cancer (unsuitable for/refusing surgery, meeting inclusion & not exclusion criteria), aged 18-75 years, from Chifeng Tumor Hospital.