By the time someone has symptoms of ovarian cancer, it is usually in an advanced state. Treatment is extraordinarily difficult, and, sadly, most people will die. One in 78 women will develop ovarian cancer, and more than 230,000 women in the U.S. are currently affected. Of these, approximately 80 percent have no family history of ovarian cancer and no indication that they were at risk for developing it.
In addition to the lack of early symptoms, late stage diagnosis occurs because there is no effective way to screen for or diagnose ovarian cancer in its earliest forms. A recent study of hundreds of thousands of women showed that screening with ultrasounds and blood testing did not save as many lives as hoped. In fact, ineffective screening leading to false reassurance (via a false negative result) is a serious concern even in high-risk patients.
Despite the name “ovarian cancer,” scientific discoveries from the last 20 years point to the fallopian tubes (two thin tubes that allow eggs to travel from the ovaries to the uterus) as the site of origin for the most common and most lethal form of ovarian cancer, high-grade serous carcinoma. Researchers found that cells lining the fallopian tubes are particularly prone to mutations in a cancer-suppressing gene called p53. These mutations allow for uncontrolled multiplication of cancerous cells and their spread throughout the body. In studying p53 mutations in ovarian cancer, scientists traced them back to tiny precancers in the fallopian tubes.
With most ovarian cancers originating in the fallopian tube, researchers decided to investigate whether people whose fallopian tubes have been removed, which is done to remove an ectopic pregnancy, treat inflammatory processes in the fallopian tube and sometimes as a form of birth control, , would have a reduced risk of developing ovarian cancer. Large epidemiologic studies show this to be the case, and it has been eye-opening for physicians like us. Given the seemingly insurtmountable challenge of developing a screening test, clinicians are beginning to offer people who have completed childbearing and who are already undergoing planned surgeries the option of removing their fallopian tubes in order to prevent ovarian cancer. This strategy, called “opportunistic salpingectomy,” is safe—and early data suggest it could reduce the risk of ovarian cancer by at least 65 percent. And as part of another gynecologic surgery, the preventative removal of fallopian tubes is supported by the American College of Obstetricians and Gynecologists and many professional societies worldwide.
Removing a person’s fallopian tubes may sound like a radical idea, especially because elective procedures do carry risk, but in the U.S. alone more than one million women undergo hysterectomies or tubal ligations every year, which are often considered elective as well. A simple change in surgical technique—removing the fallopian tubes with the uterus during hysterectomy, and removing instead of “tying” the tubes for those opting surgical contraception —would add ovarian cancer prevention to two of the most common gynecologic procedures without the need for a separate medical intervention. This is a move we, as surgeons, believe is in the best interests of our patients.
For the time being, surgery is simply the best possible option to reduce ovarian cancer risk. While ultrasound and other pelvic imaging techniques are useful for visualizing the uterus and ovaries, they cannot reliably show us the fallopian tubes. Furthermore, cancer cells from the fallopian tubes likely spread while they are still microscopic. Technology that can both “see” the tube and identify microscopic precancers would be needed for effective screening.
It has been similarly difficult to find a biomarker for early disease. Known biomarkers are detectable in the bloodstream usually only after cancer has advanced well beyond the fallopian tubes and the adjoining ovaries. Since early disease progression occurs by direct spread of microscopic cells from the fallopian tubes and onto the surfaces of organs and tissues in the abdominal cavity instead of through the blood, testing for blood biomarkers may never prove useful.
Unlike removing the ovaries, which causes menopause, removal of the fallopian tubes has no known negative health consequence after child-bearing is complete, and it adds nominal risk and time to the performance and recovery from the original surgical procedure. Salpingectomy during hysterectomy and in lieu of tubal ligation for surgical contraception was incorporated into routine practice in British Columbia more than 10 years ago. Researchers recently published preliminary data showing that this practice results in decreased incidence of ovarian cancer in the general population. The possibility that we could reduce the number of people affected by this lethal cancer with a change in surgical practice that has no lasting consequences after the completion of childbearing is a game changer. Extending this option to nongynecologic surgery would exponentially increase the number of people with access to the surgical prevention of ovarian cancer, and is the capstone of ongoing implementation research.
It’s important that people have greater agency over their health, especially when it comes to preventing a cancer for which we have neither adequate screening nor a dependable cure. Work is underway to ensure that all patients desiring surgical contraception or undergoing hysterectomy are offered an opportunistic salpingectomy. In addition, efforts to scale this beyond gynecological procedures to operations like gallbladder surgery, hernia repair, and other are mounting. Saving lives from ovarian cancer can become a reality in our lifetimes if we offer the opportunity of fallopian tube removal to the hundreds of thousands of patients undergoing abdominal operations every year in the U.S.
This is an opinion and analysis article, and the views expressed by the author or authors are not necessarily those of Scientific American.
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