RASSF2 and eosinophilia-myalgia syndrome: The homology can explain the result that no statistical differences of the epigenetic inactivation frequency of RASSF2 was found between the ectopic and the eutopic endometrial of the EAOC and EMS group, and it also inferred that hypermethylation of RASSF2 might not be involved in the pathogenesis of EMS and only be related to the malignant transformation of EMS.