High PD-1 expression level is associated with an unfavorable prognosis in patients with cervical adenocarcinoma

PURPOSE: The effectiveness of immunotherapy for cervical adenocarcinoma (CA) has not been demonstrated yet. Programmed cell death 1 (PD-1), programmed cell death-ligand 1 (PD-L1), and CD8 may be used as biomarkers of response to immune therapy in CA patients. In the present study, we aimed to investigate whether the expression levels of PD-1, PD-L1, and CD8 can predict the prognosis of patients with CA and their response to immune checkpoint inhibition therapy. METHODS: In the present study, the clinical stage for all 82 patients with cervical adenocarcinoma was classified according to the guidelines of the International Federation of Gynecology and Obstetrics (FIGO); there were 5, 48, 5, 14, 8, and 2 patients with stage IA, IB, IIA, IIB, IIIB, and IVB disease, respectively. The levels of PD-1, PD-L1, and CD8 were analyzed by the immunohistochemical analysis of the formalin-fixed paraffin-embedded tumor samples. The correlation between the expression levels and patient prognosis was analyzed using the Kaplan–Meier method and univariate and multivariate Cox proportional hazard regression models. RESULTS: We observed a significant inverse correlation between the expression of PD-1 and CD8 (p = 0.001, chi-square test). We also found a significant inverse correlation between the expression of PD-L1 and CD8 (p = 0.027). The overall survival and progression-free survival rates were significantly worse in patients with positive PD-1 expression (p = 0.031; p = 0.087, respectively). CONCLUSION: Our results suggest that a high PD-1 expression is associated with a poor prognosis in patients with CA. Further research is necessary to identify the molecular mechanisms that mediate this association. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (10.1007/s00404-020-05589-0) contains supplementary material, which is available to authorized users.