Endometriosis is a disease of unknown ethology; there are several theories that are unproven. It is known that women with such disease present with infertility, and that recurrence is very high, and apparently not depending of estrogenic stimulus. This phenomenon has been contributed to other growth factors and some oncogens. There are few studies about oncogens or other hormonal receptors; so, this study tries to evaluate them in eutopic tissue and in ectopic one of women with previous diagnosis of endometriosis. Our results show that myc as PRLr are expressed differently in the different tissues; and neu is expressed in the same way in both tissues. So, it was concluded that the cells of the endometriosis focus, have a differential status relating to expression of some of their genes, which target on their development and maintenance in a hormonal environment which differs from the uterine cavity.