Can an Ovarian Cyst Be Cancerous?

Ovarian cysts are very common in women during childbearing age and most of the time the cysts are benign. Although rare, ovarian cysts may sometimes be cancerous.

Cysts are formed as a byproduct of ovulation. Every month, a single egg follicle develops in the ovary and eventually releases the egg. Sometimes, ovulation will not occur and the follicle will continue to grow larger and larger as the fluid builds up inside it. Most of the time, this fluid will eventually reabsorb into the body and the cyst will disappear on its own. In fact, many women don’t even know that they have (or have had) an ovarian cyst.

Women with polycystic ovary syndrome (PCOS) are most likely to have cysts. In fact, multiple ovarian cysts are one of the defining characteristics of the disease. However, women without PCOS can also get ovarian cysts.

There are rare types of cysts that are, in fact, ovarian cancer. These cysts tend to have solid matter extending into the center of the cyst. Whenever solid tissue is seen in an ovarian cyst, your doctor will probably want to evaluate it by surgically removing it and performing a biopsy.

Based on the current evidence, there isn't a clear association between ovarian cancer and PCOS. While some early studies showed more than a doubling of the ovarian cancer risk in women with PCOS, others suggest that women with PCOS have a lower risk. Most of the conclusions are limited by the small size of these studies.

Similarly, while a few studies have suggested that a lack of ovulation, as occurs with PCOS, is linked to an increased risk of breast cancer, other studies have not shown any association. Further research is needed.

PCOS is associated with a 2.7-times increased risk of endometrial cancer. This may be due to a lower frequency of menstruation due associated with PCOS. 

If you start experiencing pelvic pain or discomfort, your doctor may want to check to see if you have an ovarian cyst. This can be done with a pelvic exam, in which the doctor will feel your ovary to see if there is a cyst there.

An ultrasound may also be used to confirm the presence of cysts. On an ultrasound, the cyst will appear as a fluid-filled sac. Solid cysts are more concerning and warrant further investigation. Your doctor may order additional testing, including other imaging tests, such as a CT scan or PET scan, bloodwork, and possibly a biopsy.