Simultaneous high PD-L1 and low VEGFR2 expression is associated with better overall survival in rectal cancer.

BACKGROUND

The aim of the present study was to analyze the association of programmed cell death-ligand 1 (PD-L1) and vascular endothelial growth factor receptor 2 (VEGFR2) expression levels with clinicopathological characteristics and survival to provide a treatment strategy for rectal cancer.

METHODS

Immunohistochemical staining of VEGFR2 and PD-L1 was carried out, and the association of PD-L1 and VEGFR2 expression levels with clinicopathological characteristics and survival were investigated in 77 pair-matched rectal cancer patients.

RESULTS

PD-L1 and VEGFR2 expression levels in surgical tumor tissues were higher than those in paired adjacent normal tissues, respectively (both P<0.05). The results of the 5-year overall survival (OS) analysis showed that patients with low VEGFR2 expression (66.7% 43.5%, P=0.042) and high tumor PD-L1 expression (63.9% 26.1%, P=0.001) in tumor tissues demonstrated significantly better OS. Patients with high TNM stage had poorer OS [hazard ratio (HR): 2.093, 95% confidence interval (CI): 1.027-4.087, P=0.030]. Similar results of poorer OS could be seen in patients with low tumor PD-L1 expression (HR: 3.365, 95% CI:1.747-6.481, P=0.005), as well as patients with high tumor VEGFR2 expression (HR: 0.418, 95% CI: 0.232-0.993, P=0.048).

CONCLUSIONS

The results indicated that tumor PD-L1 and VEGFR2 expression levels were associated with OS, and the combination of tumor PD-L1 and VEGFR2 levels might be an independent prognostic factor in rectal cancer.