It was observed that the pro-CRP, NSE, and CAE in the serum of patients with malignant lung tumors were 175.6 pg/mL, 33.6 ng/mL, and 31.9 ng/mL, respectively, while those of patients with benign lung tumors were 28.9 pg/mL, 12.5 ng/mL, and 10.8 ng/mL, respectively. Here, CRP is linked to lung cancer.