Platelets in Cancer: Multifaceted Roles Beyond Hemostasis to Early Detection

Tumor-educated platelets (TEPs) are emerging as powerful minimally invasive liquid bi-opsy modalities for cancer diagnosis and prognosis. Through crosstalk with tumor cells, platelets sequester tumor-derived molecules and exhibit altered RNA splicing, protein content, and activation status, all of which reflect tumor biology. Numerous studies have reported that TEP-based assays can distinguish cancer patients from controls, with sensi-tivities and specificities often exceeding 80%. Furthermore, platelet RNA signatures can identify cancer types and stages, and elevated platelet counts (thrombocytosis) and spe-cific platelet RNA/protein biomarkers are correlated with adverse prognoses in multiple malignancies, including ovarian and lung cancers. Recent large-scale investigations have validated these findings, reinforcing that TEPs are promising diagnostic and prognostic indicators. Despite this potential, some challenges remain. Ensuring sufficient platelet purity, standardizing sample processing, and accounting for non-cancerous conditions that influence platelet profiles remain critical hurdles. Moreover, tumor heterogeneity and dynamic platelet “education” can complicate assay interpretation. Ongoing efforts are focused on refining biomarker panels, improving computational models for classification, and integrating TEP data with other liquid biopsy analytes (e.g., circulating tumor DNA) for enhanced accuracy. Overall, TEP-based liquid biopsy could transform clinical deci-sion-making by enabling the earlier detection of malignancies and more precise prognos-tic assessments. With further validation in large prospective trials, TEP assays may soon provide a routine and cost-effective approach for guiding individualized cancer care.