Programmed cell death 1 expression in esophageal squamous cell carcinoma and association with clinical...

The aim of this retrospective study was to evaluate the programmed cell death 1 (PD-1) expression in esophageal squamous cell carcinoma (ESCC) and association with clinical characteristics.

From January 2009 to December 2014, 88 patients with ESCC were retrospectively included in this study. Eighty-eight cancer tissues, 35 paraneoplastic atypical hyperplasia tissues (PAHTs), and 30 relative normal esophageal tissues (RNETs) were collected and tested for expression of PD-1 by immunohistochemistry assay. The PD-1 expression and clinical characteristics of the ESCC patients were evaluated. The prognosis of the ESCC patients was compared between the PD-1 positive and negative patients.

The PD-1 positive rate was 51.2% (45/88), 22.9% (8/35), and 6.7% (2/30) for the cancer tissue, PAHT, and RNET, respectively, with statistical difference (P < 0.05); The PD-1 expression was significantly associated with lymph node metastasis (P < 0.05) and pathology grade (P < 0.05). The median overall survival was 29.8 months and 32.1 months for the PD-1 positive and negative groups without statistical difference (hazard ratio = 1.00, 95% confidence interval = 0.58-1.71, P < 0.05).

PD-1 may play a key role in the process of carcinogenesis of ESCC but not associated with prognosis and overall survival.