BACKGROUND: Programmed cell death ligand 1 (PD-L1) regulates immune responses through interaction with its receptor. PD-L1 is not only a predictor of poor prognosis but also a new therapeutic target in several malignancies. Neoadjuvant chemoradiotherapy (CRT) is an effective tool for local control of rectal cancer, but the disease recurrence rate remains high. The aim of this study was to retrospectively evaluate the correlation between PD-L1 expression and clinicopathological variables in rectal cancer after neoadjuvant CRT. MATERIALS AND METHODS: A total of 90 rectal cancer patients who underwent neoadjuvant CRT were enrolled in this study. We evaluated PD-L1 expression using immunohistochemistry. Moreover, we investigated the correlation between PD-L1 expression and tumor-infiltrating T cells, and between CD8- and Foxp3-positive cells. RESULTS: Patients with high PD-L1 expression more frequently had vascular invasion and tumor recurrence compared to patients with low PD-L1 expression (P = 0.0225 and P = 0.0051). High PD-L1 expression was significantly associated with poor recurrence-free and overall survival (P = 0.0027 and P = 0.0357). Multivariate analysis revealed lymph node metastasis and high PD-L1 expression as independent risk factors for tumor recurrence (P = 0.0102 and P = 0.0374). Numbers of infiltrating CD8-positive cells in patients with high PD-L1 expression were significantly lower than in patients with low PD-L1 expression (P = 0.0322). CONCLUSION: Our data suggest that inhibition of PD-L1 may be a new immunotherapeutic strategy to reduce tumor recurrence and improve prognosis in patients with rectal cancer after neoadjuvant CRT.
BACKGROUND:Programmed cell death ligand 1 (PD-L1) regulates immune responses through interaction with its receptor. PD-L1 is not only a predictor of poor prognosis but also a new therapeutic target in several malignancies. Neoadjuvant chemoradiotherapy (CRT) is an effective tool for local control of rectal cancer, but the disease recurrence rate remains high. The aim of this study was to retrospectively evaluate the correlation between PD-L1 expression and clinicopathological variables in rectal cancer after neoadjuvant CRT. MATERIALS AND METHODS: A total of 90 rectal cancerpatients who underwent neoadjuvant CRT were enrolled in this study. We evaluated PD-L1 expression using immunohistochemistry. Moreover, we investigated the correlation between PD-L1 expression and tumor-infiltrating T cells, and between CD8- and Foxp3-positive cells. RESULTS:Patients with high PD-L1 expression more frequently had vascular invasion and tumor recurrence compared to patients with low PD-L1 expression (P = 0.0225 and P = 0.0051). High PD-L1 expression was significantly associated with poor recurrence-free and overall survival (P = 0.0027 and P = 0.0357). Multivariate analysis revealed lymph node metastasis and high PD-L1 expression as independent risk factors for tumor recurrence (P = 0.0102 and P = 0.0374). Numbers of infiltrating CD8-positive cells in patients with high PD-L1 expression were significantly lower than in patients with low PD-L1 expression (P = 0.0322). CONCLUSION: Our data suggest that inhibition of PD-L1 may be a new immunotherapeutic strategy to reduce tumor recurrence and improve prognosis in patients with rectal cancer after neoadjuvant CRT.
Authors: Jose G Guillem; David B Chessin; Alfred M Cohen; Jinru Shia; Madhu Mazumdar; Warren Enker; Philip B Paty; Martin R Weiser; David Klimstra; Leonard Saltz; Bruce D Minsky; W Douglas Wong Journal: Ann Surg Date: 2005-05 Impact factor: 12.969
Authors: Koen C M J Peeters; Corrie A M Marijnen; Iris D Nagtegaal; Elma Klein Kranenbarg; Hein Putter; Theo Wiggers; Harm Rutten; Lars Pahlman; Bengt Glimelius; Jan Willem Leer; Cornelis J H van de Velde Journal: Ann Surg Date: 2007-11 Impact factor: 12.969
Authors: Harry H Yoon; Jared M Orrock; Nathan R Foster; Daniel J Sargent; Thomas C Smyrk; Frank A Sinicrope Journal: PLoS One Date: 2012-08-06 Impact factor: 3.240