FOLR1 and breast cancer: Similarly, analysis of the diagnostic and prognostic role of FOLR1 and FOLR3 in effusion cytology of ovarian cancer (n = 71), breast cancer (n = 10), and malignant mesothelioma (n = 10) using quantitative PCR and flow cytometry showed significantly higher concentrations of FOLR1 and FOLR3 in ovarian carcinoma samples compared to breast or mesothelioma.