Objective To explore the PGI 2 and TXA 2 for lung cancer patients and ones with lung cancer metastasis,in onder to provide nomal index for diagnosis and differential diagnosis in lung cancer metastasis.Methods To test plasma PGI 2 and TXA 2 by means of RIA in all cases.One group of patients who received non operative treatment:Six cases of patients with distant metastasis;Eight cases with hilus of long metastasis;Seven cases without metastasis.The other group of patients who received radical operation;Six cases of patients with distant metastasis;Seven cases with hilus of lung metastasis;Six cases without metastasis.Result The PGI 2/TXA 2 ratio of the patient whether distant metastasis or hilus of lung metastasis was obviously lower than that of the patients without metastasis( P