May 22, 2012 | Elena Perez
Though menopause does not cause cancer, 90% of ovarian cancers occur after menopause, according to the American Cancer Society. The association is due to the fact that certain cancer rates increase with age, which is probably why half of ovarian cancer cases have been diagnosed in women older than 63 years of age.
Ovarian cancer is also incredibly difficult to detect: There are no obvious symptoms in the early stages of the disease and women often do not show signs of ovarian cancer until the cancer is well advanced.
The American Society of Clinical Oncology states that 70% of ovarian cancers are not detected until it is far advanced and has already metastasized, or spread, to other parts of the body.
Unfortunately, by this time, late-stage ovarian cancer not only grows quickly, which shortens remission periods, but it is also resistant to certain chemotherapies.
Scientists believe that there are certain types of stem cells that could be responsible for the development and recurrence of ovarian cancer, as well as the cancer’s resistance to chemotherapy. Identifying these cells would allow doctors to test which treatments would be most effective for ovarian cancer patients.
In December, 2011, Massachusetts Hospital and Harvard Medical School reported that they isolated the cells that both fuel the cancer and resist chemotherapy treatment. These cells expressed the proteins CD44 and CD24, which play a role in the growth and maturation of cancer stem cells; as well as Epcam (3+), which is expressed in and associated with cancers; but they did not express E-cadherin (expressed in epithelial tissue), which is involved in the suppression of tumors.
Though these specific cells only comprised 1% of cancer cells, they were related to the rapid growth of cancer and shorter tumor-free intervals. These cancer stem cells showed no resistance to doxorubicin, a type of chemotherapy, but they were impacted by Mullerian inhibiting substance (MIS), a protein hormone that prevents (via apoptosis) the growth of the Mullerian ducts (which mature into female reproductive organs) during embryonic development.
Scientists believe that if women can be tested to see if their genes express these proteins, which are unaffected by doxorubicin, they may be able to effectively treat ovarian cancer with MIS.
Though more studies and tests must be made to ensure this type of treatment will be safe and successful, it seems there are great strides being made in ovarian cancer research, which can give women hope.
At the University of Pennsylvania, the Basser Research Center will focus specifically on gene mutations that cause ovarian cancer, while the Yale School of Medicine identified genetic markers for ovarian cancer, in hopes of being able to determine if a woman has an increased genetic risk of developing ovarian cancer.
In the meantime, women can still talk to their doctors about physical exams and tests that screen for ovarian cancer. The American Cancer Society also found that exercise is associated with reduced recurrence of ovarian cancer as well as survival rates, so stay active.