Identification of multiple pathways involved in the malignant transformation of endometriosis (Review)

Abstract

The association between endometriosis and malignant transformation has often been described in the medical literature. A search was conducted between 1966 and 2010 through the English language literature (online Medline PubMed database) using the keywords endometriosis combined with malignant transformation. The search revealed an increase in reports describing endometriosis and malignancy. Approximately 1.0% of women with endometriosis have lesions that undergo malignant transformation. The malignant processes that are associated with endometriosis may be classified into three groups: i) epithelial ovarian cancers (endometrioid adenocarcinoma and clear cell carcinoma), ii) other Müllerian-type tumors, including Müllerian-type mucinous borderline tumor and serous borderline tumor and iii) sarcomas such as adenosarcoma and endometrial stromal sarcoma in the female pelvic cavity. Persistent oxidative stress induced by endometriosis-dependent hemorrhage may be associated with carcinogenesis. In conclusion, the malignant transformation of endometriosis has multiple pathways of development and may share a common pathogenic mechanism; iron-induced oxidative stress derived from repeated hemorrhage.

Figures

Figure 1

Trends in the number of reports describing endometriosis and malignancy from the PubMed database, encompassing the years 1966 to 2010. The gray columns show the number of reports describing endometriosis and epithelial malignancy. The black columns show the number of reports describing endometriosis and mesenchymal malignancy. The number of reports continued to increase for both malignancies.

Figure 2

Endometriosis contributes to tumorigenesis via three major pathways. The malignant processes that are associated with endometriosis can be classified into three groups: i) epithelial ovarian cancers (endometrioid adenocarcinoma and clear cell carcinoma), ii) other Müllerian-type tumors (MMBT, SBT and LG-ET), as well as iii) sarcomas (adenosarcoma and ESS) in the female pelvic cavity.