ALDH1A1 and neoplasm: Thus, other OC biomarkers that are currently in development may be considered in a panel, such as RNA (38, 39), DNA methylation (40–42), circulating tumor cells (CTCs), and circulating tumor DNA (ctDNA) (43–45), the Cu isotope, and markers within exosomes, GSTT1, FOLR1, ALDH1, and mRNAs, most likely in conjunction with CA125 (32).