Early detection of ovarian cancer with transvaginal ultrasound

This fact box will help you to weigh the benefits and harms of transvaginal ultrasound for early detection of ovarian cancer. The information and numbers are based on the best scientific evidence currently available.

This fact box was developed by the Harding Center for Risk Literacy.

What is ovarian cancer?

Ovarian cancer is caused by an uncontrolled multiplying of abnormal cells that gradually turn into a tumor. The ovaries are part of the female reproductive system. The tumor can develop from one of the different tissues of the ovaries, leading to different kinds of ovarian cancer. Increased growth of cells through malignant or benign lesions can lead to the tumor spreading in the abdomen and pelvic cavity. At an early stage, tumors often remain unnoticed because they don’t necessarily cause physical complaints. When the tumor grows in size, symptoms can include abdominal pain, bloating, changes in bowel movements as well as unexplained weight loss or an extreme increase in abdominal girth [3].

Ovarian cancer is the eighth most widespread type of cancer in women, but the fifth most likely to lead to death. The risk of getting ovarian cancer increases with age. Being overweight, not having given birth, and infertility can also increase the risk. Ovarian cancer occurs more often in women whose immediate relatives have had breast or ovarian cancer [4].

What is early detection of ovarian cancer with transvaginal ultrasound?

Early detection (screening) targets people who do not show symptoms of a particular disease (here, ovarian cancer). The aim is to detect and treat ovarian cancer at an early stage.

An ultrasound uses high-frequency sound waves to create images of internal organs. Because the ovaries are located deep in the pelvic cavity, taking pictures of these involves inserting an ultrasound probe into the vaginal canal (transvaginal ultrasound) [5].

Who might consider early detection of ovarian cancer with transvaginal ultrasound?

Many gynecologists in Germany offer ultrasound of the ovaries for early detection of ovarian cancer. This is often part of what is known as gynecological cancer screening. When no cancer is suspected, the screening is classified as an individual health service that must be paid for out of pocket [6].

What are the alternative options for early detection?

Alternative early detection examinations include a pelvic exam and blood tests such as the tumor marker CA-125 test. When no cancer is suspected, statutory health insurance covers the yearly pelvic exam alone for patients aged 20 years and older [6].

Fact box early detection of ovarian cancer with transvaginal ultrasound
Fact box early detection of ovarian cancer with transvaginal ultrasound © Harding Center for Risk Literacy
What does the fact box show?

The fact box shows the benefits and harms of participating versus not participating in ovarian cancer screening for women aged 55 to 74 years.

The table may be read as follows:

With or without screening, about 3 out of every 1,000 women died from ovarian cancer over the course of 11 years.

The numbers in the fact box are rounded. They were reported in one study in which about 200,000 women took part. Over a period of 7 to 14 years, they had a more or less annual ultrasound of the ovaries for early detection of ovarian cancer [1].

What other aspects should be considered?

In spite of annual screening, about one out of every five tumours was either overlooked or was too small to be identified at that point by the experts responsible for interpreting the results of the ultrasound.

Furthermore, the study examined the combined effects of the screening for ovarian cancer by ultrasound and a blood test for the tumor marker CA-125. After an average of 11 years, the number of women who died from ovarian cancer did not differ between the women who were screened with these combined methods and the women who were not screened. However, we cannot yet rule out whether there may be a decrease in ovarian cancer deaths of between 0 to 1 out of every 1,000 women who took part in at least 7 to 14 years of combined screening.

Do the results provide proof (evidence) for the benefits and harms of the screening?

The presented results are drawn from a single large study. Further follow-up is necessary in order to determine the effect screening has on mortality before firm conclusions can be reached on the long-term efficacy of ovarian cancer screening [1].

Version history of the fact box
  • November 2017 (last update)

Information within the fact box was obtained from the following sources:

[1] Jacobs IJ, Menon U, Ryan A, et al. Ovarian cancer screening and mortality in the UK Collaborative Trial of Ovarian Cancer Screening (UKCTOCS): a randomised controlled trial. Lancet2016;387(10022):945-56 doi: 10.1016/s0140-6736(15)01224-6

[2] Menon U, Gentry-Maharaj A, Hallett R, et al. Sensitivity and specificity of multimodal and ultrasound screening for ovarian cancer, and stage distribution of detected cancers: results of the prevalence screen of the UK Collaborative Trial of Ovarian Cancer Screening (UKCTOCS). Lancet Oncology 2009;10(4):327-40 doi: 10.1016/s1470-2045(09)70026-9

[3] Burges A, Schmalfeldt B. Ovarian cancer: diagnosis and treatment. Dtsch Arztebl Int 2011;108(38):635-41 doi: 10.3238/arztebl.2011.0635

[4] Robert Koch-Institut. Krebs in Deutschland 2011/2012 2015 [Available from:www.gekid.de/Doc/krebs_in_deutschland_2015.pdf accessed 02.11.2017.

[5] Galanski M, Lackner K. Prinzipien der bildgebenden Diagnostik in der Onkologie. In: Schmoll H-J, Höffken K, Possinger K, eds. Kompendium Internistische Onkologie: Standards in Diagnostik und Therapie. Berlin, Heidelberg: Springer, 2006:429-48.

[6] IGeL-Monitor. Ultraschall der Eierstöcke zur Krebsfrüherkennung 2014 [Available from:www.igel-monitor.de/igel-a-z/igel/show/ultraschall-der-eierstoecke-zur-krebsfrueherkennung.html accessed 05.12.2017.