Near-Infrared Fluorescent Zwitterionic Folic Acid Probe and Serum CA125 for Enhancing Diagnostic Accuracy of Malignant Ovarian Cancer Ascites.

IntroductionAccurate detection of malignant cells in ovarian cancer ascites is essential for diagnosis and surgical staging. However, conventional cytological examination is hampered by low sensitivity and interpretive subjectivity. We evaluated a dual-modality strategy combining a near-infrared fluorescent zwitterionic folic acid (ZW-FA) probe targeting folate receptor α with serum biomarkers.MethodsAscites and peritoneal lavage specimens were processed into cell blocks. A ZW-FA fluorescence cutoff was exploratorily derived using receiver operating characteristic curve analysis. Diagnostic performance of ZW-FA staining (quantified using ImageJ), hematoxylin-eosin (H&E) staining, serum cancer antigen 125 (CA125), human epididymis protein 4, and the risk of ovarian malignancy algorithm was assessed individually and in combination. Postoperative histopathological diagnosis served as the reference standard.ResultsAmong 80 participants, the optimal ZW-FA cutoff was 48.40 (area under the curve = 0.881). Automated fluorescence quantification achieved 100.00% technical reproducibility, providing an objective and consistent readout. ZW-FA correctly classified 2 of 5 (40.00%) specimens that were non-diagnostic by H&E because of insufficient cellularity. In the complete-case comparative analysis of 65 participants, ZW-FA showed higher diagnostic accuracy than H&E staining (86.15% vs. 81.54%). The combination of ZW-FA staining and serum CA125 achieved a sensitivity of 100.00%, a specificity of 81.25%, and an accuracy of 95.38%, exceeding the accuracy of all H&E-based dual-modality strategies (≤ 90.77%).ConclusionThe ZW-FA/CA125 dual-modality strategy may improve the diagnostic assessment of ovarian cancer ascites and peritoneal lavage specimens, particularly in paucicellular samples. Further validation in larger, independent multicenter cohorts is warranted.