Ovarian Cancer—Epidemiology, Classification, Pathogenesis, Treatment, and Estrogen Receptors’ Molecular Backgrounds

Global epidemiological reports indicate a steady increase in the tendency to develop ovarian cancer. The symptoms of ovarian cancer are non-specific, and there is no effective screening tool. Most often, surgery, chemotherapy, and radiotherapy, alone or in combination, are used to treat ovarian cancer. We have a better understanding of the biology of ovarian cancer, the genetic basis of hereditary ovarian cancer, the stage of the disease, and the role of cytoreductive surgery and more effective chemotherapy, which translates into an increase in the percentage of patients who survive 5 years after diagnosis. A growing body of evidence points to the role of genetic factors in the development of cancer. It is known that mutations in the BRCA1 gene are responsible for an increased risk of developing ovarian cancer. The role of other genetic disorders, such as polymorphic variants, in increasing the risk of developing cancer is still being investigated. Ovarian cancer is a hormone-dependent cancer and its steroid hormones are estrogens. Estrogens affect cells through the estrogen receptors ERα and ERβ. An imbalance between ERα and ERβ receptor expression may, therefore, be a key step in estrogen-dependent carcinogenesis. In 60% of cancer cases, significantly elevated levels of ERα receptors are detected. The ERα receptor is encoded by the ESR1 gene, so its polymorphisms can be considered molecular markers of ovarian cancer. This article discusses the epidemiology, pathogenesis, risk factors, genetic testing, treatment, and diagnosis of ovarian cancer, as well as providing an overview of standard treatment approaches and new, targeted biologic therapies.