Objective:To study the value of the differentially expressed proteins from primary and recurrent ovarian cancer serum for early diagnosis of primary and recurrent ovarian cancer.Methods: WCX kit(Bruker Daltonics GraBH) and matrix-assisted laser desorption/ionization time-offlight mass spectrometry(MALDI-TOF-MS]technology were used to detect serum samples from 49 patients with primary ovarian cancer and 21 patients with recurrent disease.Results:In the mass range(Mr) from 1 000 to 12 000 Da,eight differentially expressed protein peaks were screened from primary ovarian cancer serum.Among them,four protein peaks with Mr 1 457,1 857,2 202, 7 761 were lowly expressed and the others with Mr 2 946,5 333,5 859,5 901 were highly expressed. Ten differentially expressed protein peaks were screened from recurrent ovarian cancer serum. Among them.1 944,1 980,2 080,2 661,2 993,4 450,4 659,5 359 Da protein expressions were increased significantly,and 1897,7868 Da protein expressions were decreased significantly.The pattern of primary ovarian cancer was applied to 8 early-stage ovarian cancer serum samples, and 7 serum samples were successfully predicted with the accuracy of 87.5%.The pattern of recurrent ovarian cancer was applied to 9 without pelvic:or abdominal mass recurrent ovarian cancer serum samples,and 8 serum samples were successfully predicled with the accuracy of 88.9%.Conclusions:Combination of MALDI-TOF-MS and WCX kit technology can directly screen the diferrential expressed protein from primary and recurrent ovarian cancer serum.They have clinical significance for enhancement of sensitivity and specificity of ovarian cancer diagnosis. Objective: To study the value of the differentially expressed proteins from primary and recurrent ovarian cancer serum for early diagnosis of primary and recurrent ovarian cancer. Methods: WCX kit (Bruker Daltonics GraBH) and matrix-assisted laser desorption / ionization time-off light mass spectrometry (MALDI-TOF-MS) technology were used to detect serum samples from 49 patients with primary ovarian cancer and 21 patients with recurrent disease. Results: In the mass range (Mr) from 1 000 to 12 000 Da, eight differentially expressed protein peaks were screened from primary ovarian cancer serum. Amm them, four protein peaks with Mr 1 457,1 857,2 202, 7 761 were lowly expressed and the others with Mr 2 946,5 333,5 859,5 901 were highly expressed. Ten differentially expressed protein peaks were screened from recurrent ovarian cancer serum. Among them.1 944,1 980,2 080,2 661,2 993,4 450,4 659,5 359 Da protein expressions were significantly increased, and 1897,7868 Da Protein expressions were decreased s ignificantly.The pattern of primary ovarian cancer was applied to 8 early-stage ovarian cancer serum samples, and 7 serum samples were successfully predicted with the accuracy of 87.5%. The pattern of recurrent ovarian cancer was applied to 9 without pelvic: or abdominal mass recurrent ovarian cancer serum samples, and 8 serum samples were successfully predicted with the accuracy of 88.9%. Conclusions: Combination of MALDI-TOF-MS and WCX kit technology can directly screen the diferrential expressed protein from primary and recurrent ovarian cancer serum. they have clinical significance for enhancement of sensitivity and specificity of ovarian cancer diagnosis.