PDCD1 and neoplasm: In conclusion, there is a significant correlation between PD-1 pathway-related immune cells and clinical pathological features of EC; tumor size, poor tumor differentiation, deep tumor infiltration, lymph node metastasis, high expression of PD-1, PD-L1, FOXP3, and CD25 are independent risk factors affecting patient prognosis; and patients with high expression of CD4 and CD8 have better prognosis.