KRT19 and cancer: In this context, the fact that TD-EVs can be used as diagnostic tumor markers, as can the presence of epithelial and stromal markers in RNA of plasmatic neoplastic EVs, the objective of this work was to validate by RT-PCR the presence of KRT19, CEA, COL11A1, and COL1A2 in RNA of plasmatic EVs in healthy and diverse-malignancy patients for the development of a non-invasive cancer diagnosis system using liquid biopsy.