Abstract
Objectives: We found programmed death-1-ligand 1 (PD-L1) was a negative prognosis factor for patients with non-small cell lung cancer (NSCLC) for 3 years follow-up in our previous study. In order to further confirm our study result, we followed up 5 years and picked up some different patients with NSCLC underwent surgical resection in the same period in our hospital.
Methods: PD-L1 expression in 120 NSCLC tissue specimens and 10 benign control samples embedded with wax were retrospectively detected by immunohistochemistry.
Results: No PD-L1 expression was found in 10 benign controls, while 57.5% tissue specimens of NSCLC had PD-L1 expression. There was no relationship between PD-L1 expression and patient age, gender, histopathological type. However, PD-L1 expression was significantly correlated to the degree of tumor cell differentiation, local lymph node metastasis, stage of tumor-node-metastasis (TNM) and survival time of patients. Poor tumor cell differentiation, local lymph node metastasis, and advanced stage of TNM were related with higher PD-L1 expression. PD-L1 negative NSCLC patients had longer overall 5-year survival time compared with PD-L1 positive ones (P<0.0001). PD-L1 status was a significant independent prognostic factor of NSCLC (χ2 = 18.153, RR = 2.946, P<0.001).
Conclusion: Up-regulated PD-L1 expression in NSCLC is related with the degree of tumor cell differentiation, local lymph node metastasis and stage of TNM. PD-L1 expression is an important risk factor associated with poor prognosis of NSCLC.
- © 2011 ERS