THBS2 and clear cell adenocarcinoma: Both approaches identified THBS2 (thrombospondin 2) and ERG (erythroblastosis virus E26 oncogene homolog) genes to be significantly differentially methylated across all three ovarian carcinoma histological types and, specifically, between endometrioid and clear cell carcinomas and suggested that different biological pathways are important in the natural history of the histological types.