Abstract: [Abstract]Objective: To investigate the change pattern of perioperative plasma D-dimer levels in patients with lung cancer, and the relationship of plasma D-dimer level with clinical pathological features. Methods: 64 cases of lung cancer patients were taken as cancer group, and 15 cases of benign lung disease were as control group. The plasma D-dimer was determined two days before operation and the first, fifth, ninth day after operation. The clinical pathological parameters and type of surgery were evaluated at the same time. Results: Plasma D-dimer levels in patients with lung cancer were much higher than those in control group(t=3.087，P＜0.05). D-dimer levels in TNM stageⅠpatients were lower than those in stageⅡor Ⅲ patients(P＜0.05, respectively). Plasma D-dimer levels in small cell cancer patients were higher than non-small cell cancer patients(P＜0.05). D-dimer levels were changing in different time of perioperative period(P＜0.001). In cancer group, D-dimer levels were up-regulated on the first day after operation, and then significantly down-regulated on the fifth and ninth day. D-dimer levels on the ninth day after operation were much lower than levels before operation(pairwise comparison, P＜0.05, respectively). In control group, D-dimer levels were increased on the first day after operation, and were unchanged on the fifth day (P=0.174), then were decreased on the ninth day. And there were no significantly difference between levels on the ninth day after operation with D-dimer levels before operation (P=0.631). D-dimer levels in cancer group and control group were significantly different (P=0.005). In addition to the fifth day (P=0.069), postoperative D-dimer levels in cancer group were much higher than control group (the first day P=0.009, the ninth day P=0.017). Conclusions: Plasma D-dimer levels before operation in patients with lung cancer were much higher than those in benign lung disease, and were associated with TNM stage and cell type. D-dimer levels in lung cancer patients were significantly increased from the first day after operation, and then decreased significantly until the ninth day, which were lower than D-dimer levels before operation. But they were still higher than benign lung disease patients at the same time interval.

Key words: D-dimer, Lung Neoplasms, Perioperative Period, Surgery