Objective To prepare human vascular endothelial growth factor (hVEGF) radioimmunoassay (RIA) and chemiluminescence immunoassay (CLIA) kits and evaluate their clinical value in diagnosis of early lung cancer and colorectal cancer.

Methods A detection method was established according to the technical indices of the kits. The techniques for coating magnetic particles and ¹²⁵iodine and acridine ester labeling with antibody were evaluated. Sensitivity, precision, and recovery of the kits were determined. The sensitivity and specificity of the kits in the diagnosis of early cancers (lung and colorectal cancers) were evaluated by testing cancer and normal serum samples. Independent sample t-test was used for inter-group comparison.

Results The optimal ratios were as follows: 1 mL of magnetic particles to 1 mg of the antibody, 55.5 MBq ¹²⁵iodine to 0.1 mg of the antibody, and 25 μg acridine ester to 0.2 mg of the antibody. The detection sensitivities of RIA and CLIA kits were 17.6 and 9.2 pg/mL respectively. For precision, the CLIA kit had slightly higher intra-batch variability and lower inter-batch variability than the RIA kit. The mean recovery levels of the RIA and CLIA kits were 103.28% and 101.85% respectively, and the latter had higher detection accuracy. The clinical sensitivity and specificity in the diagnosis of lung cancer and colorectal cancer were all above 90%. RIA kit and CLIA kit showed that the specificity of hVEGF in normal serum samples was 98.11% (104/106) and 99.06% (105/106), respectively.. There were significant differences in hVEGF between cancer patients and normal subjects (t=−16.695–−14.920, all P<0.01).

Conclusions The technical indices of the hVEGF RIA and CLIA kits were good. The CLIA kit had higher sensitivity and specificity than the RIA kit and has clinical value in screening and auxiliary diagnosis of early lung and colorectal cancers.