[Malignant degeneration in women operated on for endometriosis]

The endometriosis can undergo estrogen-dependent changes similar to endometrium and may carry a risk for developing hyperplasia and carcinoma during unopposed estrogen stimulation. We reviewed the existing literature to analyze the potential of malignancy arising from extraovarian endometriosis by estrogen stimulation. Our two cases are also discussed. According to our study there are 21 cases published in the literature of malignant transformation of endometriosis after estrogen stimulation. The most common place for malignant trans formation is the vagina. The most common hystological type is adenocarcinoma in 13 cases. Our two cases were with adenocarcinoma and adenosquamous carcinoma. The incidence of malignant transformation of the endometriosis can not be estimated based upon these cases. There is a need for randomised clinical trials.

The estrogen stimulation may lead to premalignant or malignant transformations of the residual foci of endometriosis. That is why addition of progestins to the estrogen substitutional therapy should be considered in women with endometriosis after total hysterectomy with oophorectomy, especially if a residual foci are present or suspected. With our study we think we can make more clear the way an endometriosis is transformed into a malignancy.