Having questions about ovarian cancer is natural. People trying to understand more about the condition may want to know:
- how common ovarian cancer is
- who is most at risk of developing ovarian cancer
- what the outlook is for people with an ovarian cancer diagnosis
While cancer is different for every person, ovarian cancer statistics can provide an idea of what to expect. Read on to learn more about ovarian cancer.
What is ovarian cancer?
Ovarian cancer affects the female reproductive system.
Ovarian cancer is a type of cancer that affects the ovaries, which are the female reproductive glands. The two ovaries sit either side of the uterus, or womb.
Ovarian cancer may begin in the ovaries or in the fallopian tubes, which connect the ovaries to the womb.
Ovarian cancer can develop from various cell types, but tumors usually arise from the epithelial cells that form the outer layer of the ovaries.
Not all epithelial tumors are cancerous. Doctors refer to those that are cancerous as epithelial ovarian carcinomas. They classify these carcinomas into different grades, stages, and types after looking at the cells in a laboratory. The most common type is called a serous carcinoma.
Doctors grade ovarian cancer tumors from grade 1 to grade 3 depending on how closely the cells resemble normal tissue. Grade 1 tumors look the most like noncancerous tissue and are usually less severe. Grade 3 tumors look the least like healthy tissue, and people with this grade of tumor have the worst outlook.
Doctors also give ovarian cancer a stage from stage 1 to stage 4, which relates to the size of the tumor and whether or not the cancer has spread outside of the ovary.
Finally, doctors determine the type of ovarian cancer. The type depends on how well the cancer cells respond to treatment with chemotherapy and how fast they grow. Type 1 tumors grow slowly but do not respond well to chemotherapy. Type 2 tumors grow quickly but do respond to chemotherapy.
How common is ovarian cancer?
In the United States, ovarian cancer accounts for around 3 percent of cancers in women.
Statistics suggest that ovarian cancer is gradually becoming less common. According to the ACS, the rate of diagnosis of ovarian cancer has steadily declined over the past 20 years.
Below, we explain which groups of people ovarian cancer is most likely to affect:
Ovarian cancer mainly affects older individuals. About half of the people who receive a diagnosis of ovarian cancer are over the age of 63 years.
White people are more likely than African-American people to develop ovarian cancer.
The following data is from the Centers for Disease Control and Prevention (CDC). The table shows the number of new cases of ovarian cancer per 100,000 women for each U.S. state in 2015. The figures are age-adjusted to the 2000 U.S. standard population.
|U.S. State||New cases per 100,000|
|District of Columbia||12.5|
The ACS anticipate that California will be the U.S. state with the highest number of new ovarian cancer diagnoses in 2018. They predict that the U.S. states with the fewest new cases will be South Dakota and Vermont.
It is important to remember that rates of ovarian cancer are different in each state for many reasons, one of which is differing population density. Geography is not a causal factor in the development of ovarian cancer.
Certain lifestyle factors, such as smoking, can increase the risk of developing ovarian cancer.
Many different factors may increase a person's risk of developing ovarian cancer. These risk factors include:
- getting older
- being overweight or obese
- having a child after 35 years of age or never carrying a pregnancy to full term
- having in vitro fertilization (IVF)
- using hormone replacement therapy (HRT) after menopause
- having a family history of ovarian cancer or a type of inherited gene change called family cancer syndrome
- having had breast cancer
- smoking may increase the risk of mucinous-type ovarian cancer
Doctors use 5-year survival rates to compare the outlook for people with different types of cancer. For all types of ovarian cancer, the average 5-year relative survival rate is 47 percent. This means that people with ovarian cancer are 47 percent as likely as people who do not have the condition to live for at least 5 years following diagnosis.
The 5-year survival rates vary depending on the type of ovarian cancer.
Only around 14.8 percent of people with early-stage ovarian cancer receive an early diagnosis. An early diagnosis can improve an individual's outlook. For example, the 5-year relative survival rate of ovarian cancer that has not spread outside the ovary is about 92 percent.
As with any form of cancer, the sooner a person receives a diagnosis, the better their outlook tends to be. Outlook also improves if a doctor diagnoses cancer in its early stages.
People may feel more informed once they understand the statistics relating to ovarian cancer. However, it is vital to remember that everyone's experience of cancer is different.
Anyone with concerns about potential cancer symptoms should speak to their doctor straight away. People with questions about cancer following a diagnosis should also talk to a healthcare professional.
The ACS offer a range of resources to help people learn more about their cancer and find local support groups.