Conclusion
CRT aggravated immunosuppression and increased PD-1 expression in T lymphocyte subsets in patients with ESCC, possibly related to the radiation field. PD-1 expression in T lymphocyte subsets can predict short-term outcomes in patients and provide a theoretical basis for the sequential application of PD-1 immunosuppressants after radiotherapy and chemotherapy.
Methods
Seventy-three patients with ESCC who were treated with definitive CRT were enrolled. Before and after CRT, flow cytometry was used to detect thePD-1 expression in the peripheral blood and related immune indicators. Peripheral blood from 10 healthy individuals was used as control.
Objective
This study aimed to observe the dynamic changes in the expression of T lymphocytes, natural killer (NK) cells, and PD-1 in patients with first-diagnosed esophageal squamous cell carcinoma (ESCC) before and after chemoradiotherapy (CRT) and evaluate the impact of PD-1 expression in peripheral blood on the short-term outcome of patients with ESCC. Patients and
Results
The percentages of CD3+ (p = 0.018), CD4+ (p < 0.001), and CD8+ T cells (p < 0.001); NK cells (p = 0.009); and the CD4+/CD8+ ratio (p < 0.001), as well as PD-1+CD3+ (p < 0.001), PD-1+CD4+ (p < 0.001), and PD-1+CD8+ (p < 0.001) T cells, before CRT significantly differed from those in the post-CRT group. The percentages of PD-1+CD8+ T cells differed significantly between the radiotherapy alone and CRT groups (p < 0.05). PD-1 expression in CD3+, CD4+, and CD8+ T cells significantly decreased in patients achieving overall response rate (all p < 0.05). Compared with those in the incomplete response group, PD-1+CD8+ T cells significantly decreased in the CR group (p < 0.05).