To investigate the correlation between the expression levels of HIF-1α and PD-L1 and the risk of lymphatic metastasis in patients with non-small cell lung cancer (NSCLC).

A total of 97 NSCLC patients who underwent surgical treatment in our hospital from December 2015 to December 2017 without lymph node metastasis were selected. Immunohistochemical analysis was used to detect the expression of HIF-1α and PD-L1 in cancer lesions of all patients. Then a follow-up period of 24 months was performed to record the occurrence of lymphatic metastases. All patients were grouped according to the expression levels of HIF-1α and PD-L1, and the differences in the risk of lymphatic metastasis in patients with different expression levels of the two proteins during the follow-up period were analyzed. COX regression analysis was used to determine the relationship between HIF-1α and PD-L1 and NSCLC lymph node metastasis.

All patients were followed up for an average of 19 (12, 24) months. A total of 92 patients completed the follow-up. 36 cases of lymph node metastasis occurred. The rate of lymph node metastasis was 39.13%. Lymph node metastasis rates in patients with high and low expression of HIF-1α were 92.6% and 26.9%, respectively. Lymph node metastasis rates in patients with high expression of HIF-1α were significantly higher than those in patients with low expression (log-rankχ²=63.052; P<0.001) . The incidence of lymph node metastasis in patients with high PD-L1 expression and low expression was 82.1% and 21.3%, respectively. The lymph node metastasis rate in patients with high PD-L1 expression was significantly higher than that in patients with low expression (log-rankχ²=39.555; P<0.001). HIF-1α high expression (HR=25.790, 95%CI=10.005-30.287), PD-L1 high expression (HR=16.693, 95%CI=12.014-20.356), CEA (HR=1.058, 95%CI=1.013-1.106) is a risk factor for lymphatic metastasis in patients with NSCLC (P<0.05).

The high expression of HIF-1α and PD-L1 has significant correlation with the risk of lymphatic metastasis in patients with NSCLC, and can be used as targets for early prediction and treatment.