RATIONALE: MAGE-A4 is a cancer-testis antigen widely expressed in various mesenchymal tumors but absent in normal tissues, making it an ideal immunotherapeutic target. Given the limited effectiveness of conventional therapies in advanced mesenchymal tumors, this study seeks to explore a novel treatment approach by engineering autologous T cells with a high-affinity TCR specific for MAGE-A4. PUOPOSE: This exploratory clinical study will assess safety profiles, treatment tolerance, and preliminary antitumor activity in patients with advanced mesenchymal malignancies.