Objective: To investigate the clinical significance of the serum VEGF as a marker for monitoring the clinical course of tumor patients cured by surgery and radiotherapy.Methods: Enzyme linked immunosobent assay (ELISA) was used to detect serum levels of VEGF in the patients with carcinoma. Results: X-ray irradiation could induce thetumor cells to express and secret VEGF. Patients withelevated values of serum VEGF 60 days after radiotherapy had higher rate of tumor recurrence and metastasis. There was more chance of metastasis in lung cancer patients with higher level of VEGF after surgical resection (12/21). Less post-operation (3 months~4 years) patients without relapse or cancerometastasis showed elevated values of serumVEGF than those with relapse or cancerometastasis. There was negative correlation between the serum Hb and VEGF in the tumor patients (g = -0.289, P<0.01). In the 28 patients with normal Hb levels at pre-operation, 17 patients withdecreased Hb levels had more chance getting higher VEGF after operation than the others (P<0.05). Conclusion:clinical manifestation should be considered in theapplication of serum VEGF as a tumor marker, aprognostic factor, and a recurrence indicator of tumor. To determine the levels of serum VEGF and Hb, correct the low level of Hb and block the effect of VEGF by specialmeans may be helpful for tumor patients. Objective: To investigate the clinical significance of the serum VEGF as a marker for monitoring the clinical course of tumor patients cured by surgery and radiotherapy. Methods: Enzyme linked immunosobent assay (ELISA) was used to detect serum levels of VEGF in the patients with carcinoma Results: X-ray irradiation could induce the tumor cells to express and secret VEGF. Patients withelevated values ​​of serum VEGF 60 days after radiotherapy had higher rate of tumor recurrence and metastasis. There was more chance of metastasis in lung cancer patients with higher level of VEGF after surgical resection (12/21). Less post-operation (3 months to 4 years) patients without relapse or cancerometastasis showed elevated values ​​of serum VEGF with those with relapse or cancerometastasis. There was negative correlation between the serum Hb and VEGF in the tumor patients (g = -0.289, P <0.01). In the 28 patients with normal Hb levels at pre-operation, 17 patients with depened Hb levels had more chance g etting higher VEGF after operation than the others (P <0.05). Conclusion: clinical manifestation should be considered in the application of serum VEGF as a tumor marker, a prognostic factor, and a recurrence indicator of tumor. To determine the levels of serum VEGF and Hb , correct the low level of Hb and block the effect of VEGF by special mayans be be helpful for tumor patients.