Correlation of mutation with programmed death ligand-1 (PD-L1) expression and their clinicopathological significance in colorectal cancer.

BACKGROUND

The prognostic significance of mutations in colorectal cancer (CRC) remains controversial. Recently, an association between programmed death ligand-1 (PD-L1) and mutations has been reported. The study presented here was conducted to investigate the effect of mutations on the prognosis of CRC patients and the association between mutations and PD-L1.

METHODS

mutations were analyzed by targeted next-generation sequencing using formalin-fixed paraffin-embedded specimens from 224 primary CRC patients. PD-L1 expression was evaluated by immunohistochemical staining.

RESULTS

mutations and PD-L1 expression were detected in 21.4% and 10.3% of CRC patients, respectively. mutations were significantly correlated with right-side colon cancer (P=0.011) and were correlated inversely with lymph node metastasis (P=0.026), distant metastasis (P=0.047), and high TNM stage (P=0.036). In univariate analysis, mutations were correlated with longer relapse-free survival in CRC patients. PD-L1 expression was correlated significantly with mutations (P<0.001).

CONCLUSIONS

mutations were associated with favorable prognostic factors, longer relapse-free survival, and expression of PD-L1. Further investigation is needed to identify whether mutations are a good prognostic factor. Additionally, further studies are needed to understand the mechanisms behind the correlation between mutations and PD-L1 expression.