Research Suggests Some Ovarian Cancers Begin in a Fallopian Tube
Last updated: June 2021
Doctors once thought that ovarian cancer began in the ovaries. However, recent research shows that some ovarian cancers actually begin in the fallopian tubes. This new information may help guide prevention, early detection, and treatment.
What are the fallopian tubes?
There are 2 fallopian tubes in a woman’s anatomy. These long, thin tubes connect the ovaries to the uterus. The uterus, or womb, has 1 ovary and 1 tube on each side. Eggs travel from the ovaries through the fallopian tubes to the uterus to be fertilized or passed during menstruation.1
What is high-grade serous ovarian carcinoma (HGSOC)?
There are many types of ovarian cancer. High-grade serous carcinoma (HGSOC) is the most common subtype. Three out of every 4 who have ovarian cancer have it. In most cases, it is diagnosed at later stages, which makes it harder to treat successfully. HGSOC is also the most aggressive type of ovarian cancer.2,3
Doctors originally thought HGSOC started in the surface tissue of the ovary. This tissue is also called the epithelium. Now, they know that there are 2 spots where ovarian cancer cells begin to grow:2,3
- The surface of a fallopian tube
- The surface of an ovary
Linking early tumors with ovarian cancer
More than 10 years ago, doctors found that fallopian tube lesions called serous tubal intraepithelial carcinomas (STIC) might be forerunners to HGSOC. Women with BRCA 1 and BRCA2 mutations who had their fallopian tubes and ovaries removed were found to have these lesions.4
Recent research has confirmed this early finding. Doctors now believe the time between the development of these early tumors and ovarian cancer is about 7 years. This means that early detection could help those with ovarian cancer get treatment when it is most effective.5
What we know now
Having BRCA genes and the TP53 gene mutation are strongly linked to fallopian tube lesions that later become ovarian cancer.2,3
Since the discovery of STIC, 3 other possible precancerous lesions have been found. These include:3
- Low-grade serous tubal intraepithelial lesions (STIL)
- Secretory cell outgrowths (SCOUTS)
Science also shows that surgery to remove the fallopian tubes but not the ovaries provide a much lower risk of ovarian cancer. Leaving the ovaries in place allows these organs to release hormones that reduce the risk of cancer. However, because the ovaries are still there, cancer can still begin there.5
More research is needed. There is no screening for ovarian cancer or precancerous lesions. There is also no recommended guideline for what to do when these lesions are found and removed. Doctors also need to know more about the genetic mutations linked to fallopian tube lesions (STIC).
Things to consider
Talk with your doctor about current research on fallopian tube lesions. You may want to ask if you are a candidate for removal of the fallopian tubes to help reduce your risk. Or, it may be possible to take a biopsy of your fallopian tubes to look for abnormal cells. Genetic screening may also be a possibility. Genetic tests may reveal whether you have any of the gene mutations linked to STIC or ovarian cancer.
Have you heard of platinum-resistant ovarian cancer?