CPS score, also known as Combined Positive Score, refers to the ratio of the number of PD-L1 staining-positive cells (tumor cells, lymphocytes, macrophages) to the total number of tumor cells in the sample, which is divided into percentile values between 1 and 100 to determine the effectiveness of immunotherapy. For different tumors such as gastric cancer, head and neck squamous cancer, uroepithelial cancer, etc., the CPS scoring criteria are different, as follows:
1. Gastric cancer: For recurrent locally advanced/metastatic gastric cancer/gastroesophageal junction adenocarcinoma (GC/GEJA), CPS ≥1 is the standard for first-line treatment. Pembrolizumab blocks the interaction between PD-1 and its ligands PD-L1 and PD-L2, thereby activating T lymphocytes to kill gastric cancer cells. In addition, CPS ≥5 is the standard for nabulizumab combination chemotherapy.
2. Head and neck squamous carcinoma: For recurrent/metastatic head and neck squamous carcinoma, CPS ≥1 is an indication for pembrolizumab for non-nasopharyngeal carcinoma.
3. Uroepithelial carcinoma: For locally advanced/metastatic uroepithelial carcinoma (UC), CPS ≥10 is a criterion for immunotherapy with tirilizumab.
In conclusion, CPS score is the indication of whether advanced or metastatic malignant tumors can be treated with immunotherapy, and a high CPS score indicates a good effect by immunotherapy, while a low CPS score indicates that immune checkpoint inhibitors are less effective against the tumor.
Therefore, the treatment of cancer should follow the principle of individualization and adopt appropriate treatment according to the actual condition.