Testicular germ cell tumors (TGCTs) are nearly universally curable malignancies. Nevertheless, standard cisplatin-based chemotherapy is not curative in a small subgroup of patients. Previously, we showed that PD-L1 overexpression is associated with worse prognosis in TGCTs, while tumor infiltrating lymphocytes (TILs) are prognostic in different types of cancer. This study aimed to evaluate the prognostic value of PD-1 and PD-L1 expressing TILs in TGCTs.
PD-L1 positive TILs were found significantly more often in seminomas (95.9% of patients) and embryonal carcinomas (91.0%) compared to yolk sac tumors (60.0%), choriocarcinomas (54.5%) or teratomas (35.7%) (All p < 0.05). TGCTs patients with high infiltration of PD-L1 positive TILs (HS ≥ 160) had significantly better progression-free survival (HR = 0.17, 95% CI 0.09 - 0.31, p = 0.0006) and overall survival (HR = 0.08, 95% CI 0.04 - 0.16, p = 0.001) opposite to patients with lower expression of PD-L1 (HS < 150). PD-1 expressing TILs were not prognostic in TGCTs.
Surgical specimens from 240 patients with primary TGCTs were included into this translational study. The PD-1 and PD-L1 expression on tumor and TILs were detected by immunohistochemistry using anti-PD-1 and anti-PD-L1 monoclonal antibody. Scoring was performed semiquantitatively by weighted histoscore (HS) method.
The prognostic value of PD-L1 expressing TILs in TGCTs was demonstrated for the first time.
Oncotarget. 2017 Mar 28 [Epub]
Michal Chovanec, Zuzana Cierna, Viera Miskovska, Katarina Machalekova, Daniela Svetlovska, Katarina Kalavska, Katarina Rejlekova, Stanislav Spanik, Karol Kajo, Pavel Babal, Jozef Mardiak, Michal Mego
nd Department of Oncology, Comenius University, Faculty of Medicine & National Cancer Institute, Bratislava, Slovak Republic., Department of Pathology, Comenius University, Faculty of Medicine, Bratislava, Slovak Republic., st Department of Oncology, Comenius University, Faculty of Medicine & St. Elisabeth Cancer Institute, Bratislava, Slovak Republic., Department of Pathology, Slovak Medical University St. Elisabeth Cancer Institute, Bratislava, Slovak Republic., Translational Research Unit, 2nd Department of Oncology, Comenius University, Faculty of Medicine & National Cancer Institute, Bratislava, Slovak Republic.