Abstract
Objective: Differentiating ovarian cancer from benign and borderline adnexal lesions remains challenging. We previously identified nine platelet protein markers associated with ovarian cancer. This study aimed to validate these markers on platelet-derived extracellular vesicles (EVs) and assess their ability to distinguish ovarian cancer from benign and borderline adnexal lesions. Methods: Patients were recruited between 2021 and 2025 at Uppsala University Hospital and Gävle Hospital, Sweden, and grouped according to postoperative histopathological diagnosis. Platelet-free plasma samples were analyzed by flow cytometry. Platelet-derived EVs (CD41+) and nine platelet protein markers (ACTN4, CRKL, ERP29, GELS, MAP1A, MYCT1, PHB, RELN, and SRC) were quantified on CD41+CD62P+ and CD41+CD62P− EV populations. Group differences were assessed using non-parametric tests, binary and proportional odds logistic regression, and Boruta feature selection. Results: Total CD41+ EVs and CD41+CD62P+ EVs did not differ between groups. Levels of CD62P+anti-GELS, CD62P+anti-SRC, and CD62P−anti-MYCT1 were highest in ovarian cancer. CD62P+anti-GELS was independently associated with ovarian cancer in both crude analysis (OR 1.47, 95% CI 1.16-1.85; C-statistic 0.63) and analysis adjusted for age and CA125 (OR 1.59, 95% CI 1.21-2.08; C-statistic 0.82). Boruta algorithm identified ultrasound assessment and CA125, followed by CD62P+anti-GELS, CD62P−anti-SRC, CD62P−anti-ERP29, CD62P−anti-MAP1A, and CD62P+anti-ACTN4, as the variables associated with ovarian cancer. CD62P+anti-ERP29 was specifically associated with advanced-stage ovarian cancer compared with other abdominal malignancies (OR 2.43, 95% CI 1.53-4.38; C-statistic 0.85). Conclusion: CD62P+anti-GELS on platelet EVs was independently associated with ovarian cancer after adjustment for age and CA125. Together with CD62P+/CD62P− anti-SRC, CD62P+anti-ACTN4, CD62P−anti-ERP29 and CD62P−anti-MAP1A, it may complement ultrasound evaluation and CA125 in distinguishing ovarian cancer from benign and borderline adnexal lesions.