Cancer Center, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China.
Front Immunol. 2021 Dec 7;12:759250. doi: 10.3389/fimmu.2021.759250. eCollection 2021.
It was widely accepted that programmed death-ligand 1 (PD-L1) positive, tumor mutational burden-high (TMB-H) or microsatellite instability-high (MSI-H) tumor are prone to have better treatment response to immune checkpoint blockade. The value of immune checkpoint blockade in PD-L1 negative gastric cancer patients has been questioned due to lower objective response rate (ORR).
We report an unusual case of a PD-L1 negative, proficient mismatch repair (pMMR)/microsatellite stability (MSS), tumor mutational burden-low (TMB-L) gastric cancer patient who achieved good response to immune checkpoint blockade after failure of systematic treatment. Multiple lymph nodes and bone metastases are the main characteristics of this patient. The patient survived for more than 30 months after diagnosis.
This case suggested that PD-L1 negative gastric cancer patient may also benefit from immune checkpoint blockade. In gastric cancer, patients with lymph node metastasis may be potential beneficiaries.
程序性死亡配体 1（PD-L1）阳性、肿瘤突变负担高（TMB-H）或微卫星不稳定高（MSI-H）的肿瘤对免疫检查点阻断治疗更敏感，这一观点得到了广泛认可。由于客观缓解率（ORR）较低，免疫检查点阻断在 PD-L1 阴性胃癌患者中的应用价值受到了质疑。
我们报告了一例 PD-L1 阴性、错配修复功能完整（pMMR）/微卫星稳定（MSS）、肿瘤突变负担低（TMB-L）的胃癌患者，该患者在系统治疗失败后对免疫检查点阻断治疗有较好的反应。该患者的主要特征是多发淋巴结和骨转移。诊断后，该患者的生存期超过 30 个月。
该病例提示 PD-L1 阴性的胃癌患者可能也能从免疫检查点阻断治疗中获益。在胃癌中，有淋巴结转移的患者可能是潜在的获益人群。
