ESR1 and leiomyoma: In conclusion, considering that no evidence of systemic exogenous or endogenous hyperestrogenism are on record in our case, it is arguable that the presence of a leiomyoma, close to a pool of adenomyotic foci, along with the overexpression of estrogen receptors and enzymes involved in steroidogenesis, represent a hyperestrogenic microenvironment with converging sources of estrogen biosynthesis.