Purpose <p>This study aimed to evaluate the serum of ovarian cancer (OC) patients using two-dimensional polyacrylamide gel electrophoresis (2D PAGE) and electrospray ionization liquid chromatography mass spectrometry (ESI-LCMS) analysis for the detection of ovarian cancer-associated plasma proteins.</p> Methods <p>Our study included 50 serum samples collected from newly diagnosed OC patients and 50 serum samples from age-matched female controls. These serum samples were used to compare the 1-dimensional and 2-dimensional gel electrophoresis (2DE) protein profiles and identify potential markers of OC progression using ESI-LCMS.</p> Results <p>By analysing and comparing the two-dimensional gel spot patterns and identification using ESI-LCMS, we could observe stage-specific patterns in the expression of alpha-1 antitrypsin (A1AT), a steady increase from stage I to stage IV. There was also a substantial decrease in its expression after debulking surgery and chemotherapy.</p> Conclusion <p>In conclusion, our study revealed that A1AT might be used as a putative biomarker for disease confirmation and progression rather than early detection. However, large studies with large cohorts are needed to generalize the conclusion.</p>