Background. The pathological subtype of osteosarcoma is one of the most common malignant bone tumors. Notably, chemotherapy-resistant metastatic osteosarcoma has been reported to cause significant mortality and shows poor prognosis with the currently available multidisciplinary treatments. This study investigated whether combined adoptive TIL and anti-PD1 therapy improves the prognosis of patients with chemotherapy-resistant metastatic osteosarcoma. Methods. A total of 60 patients with chemotherapy-resistant metastatic osteosarcoma between June 2016 and March 2018 were enrolled. The primary endpoint was to evaluate the safety and adverse effects (AEs) of infusions of TIL and anti-PD1 therapy in the patients. Besides, secondary endpoints included assessing the objective response rate (ORR), progression-free survival time (PFS), and overall survival time (OS). Results. We reported that combined TIL therapy and anti-PD1 therapy is safe and all treatment-related AEs were reversible or manageable. The ORR of all the patients is 36.67%, and patients with more infusions of TIL and CD8⁺TIL, less infusions of CD8⁺PD1⁺TIL, and less infusion of CD4⁺FoxP3⁺TIL exhibited increased PFS and OS. Conclusion. This study determined that combined TIL and anti-PD1 therapy is safe and effective in metastatic osteosarcoma patients with chemotherapy resistance.

中文翻译：

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过继性 TIL 治疗联合抗 PD1 治疗耐药转移性骨肉瘤患者的回顾性分析

背景。骨肉瘤的病理亚型是最常见的恶性骨肿瘤之一。值得注意的是，据报道，化疗耐药的转移性骨肉瘤会导致显着的死亡率，并且在目前可用的多学科治疗中预后不良。本研究调查了过继性 TIL 和抗 PD1 联合治疗是否能改善化疗耐药转移性骨肉瘤患者的预后。方法. 2016 年 6 月至 2018 年 3 月期间共有 60 名化疗耐药转移性骨肉瘤患者入组。主要终点是评估患者输注 TIL 和抗 PD1 治疗的安全性和不良反应 (AE)。此外，次要终点包括评估客观缓解率（ORR）、无进展生存期（PFS）和总生存期（OS）。结果。我们报道联合 TIL 治疗和抗 PD1 治疗是安全的，所有与治疗相关的 AE 都是可逆或可控的。所有患者的ORR为36.67%，TIL和CD8 ⁺ TIL输注较多，CD8 ⁺ PD1 ⁺ TIL输注较少，CD4 ⁺ FoxP3 ^{+输注较少的患者}TIL 表现出增加的 PFS 和 OS。结论。本研究确定了 TIL 和抗 PD1 联合治疗对化疗耐药的转移性骨肉瘤患者是安全有效的。