Benign Ovarian Tumors

Benign ovarian tumors at a glance

  • Benign ovarian tumors are slow-growing solid masses in or on a woman’s ovary.
  • Ovarian tumors are most often benign, however, some types may develop into ovarian cancer if left untreated.
  • Symptoms are rare and tumors are usually detected during a routine pelvic exam or Pap test.
  • Treatment typically involves surgical removal of the tumor and sometimes the surrounding tissue or the affected ovary.
  • Fertility is often preserved after treatment.

What is a benign ovarian tumor?

An ovarian tumor is a slow-growing abnormal mass of tissue on or in a woman’s ovary. A tumor is a solid mass, unlike a fluid-filled ovarian cyst. Tumors, which occur in many areas of the body, are abnormal growths that don’t have any purpose. A tumor can be benign or cancerous (malignant), but ovarian tumors are typically benign.

For information on cancerous ovarian tumors, read ovarian cancers.

Benign ovarian tumors most commonly occur in women of childbearing age. They occur in about 50 percent of women with irregular menstruation and in about 30 percent of women with regular menstruation.

Benign ovarian tumors are divided into three main types, based on where the abnormal cell growths originated:

Surface epithelial tumors ­­– these tumors begin in the cells lining the surface of the ovary. It is the most common type of ovarian tumor.

Stromal tumors ­­– these benign and malignant tumors begin in the part of the ovary that manufactures female reproductive hormones. It is very rare and when cancerous is considered a low-grade cancer.

Germ cell tumors – these tumors begin in the cells that develop into eggs. The majority of germ cell tumors are benign, but sometimes can develop into cancer. These are most common in younger women and, if treated early, fertility can be preserved.

Risk factors for ovarian tumors

The causes of benign ovarian tumors are not well understood. Some research suggests correlations between certain risk factors and the development of ovarian tumors:

  • Obesity
  • Infertility
  • Family history of ovarian tumors or ovarian cancer.

Ovarian tumor symptoms and diagnosis

Ovarian tumors are generally asymptomatic, meaning a woman rarely has any noticeable symptoms. In some women, the tumor is so undetectable that it eventually grows large enough to cause pelvic or abdominal discomfort by encroaching on nearby organs. In these cases symptoms may include:

  • Abdominal pain
  • Trouble urinating or frequent urination
  • Low back pain
  • Pain with sexual intercourse
  • Bad cramps with a woman’s periods
  • Feeling full quickly after eating, or no appetite
  • Nausea or vomiting.

Since symptoms are rare, tumors are usually spotted during routine physical exams, including a pelvic exam or Pap test. As such, women should always have routine pelvic exams to help ensure that changes in the ovaries are diagnosed as early as possible.

Ovarian tumor removal and treatment

In some cases, benign tumors need no treatment; doctors may simply use “watchful waiting” to make sure they cause no problems.

When ovarian tumors are present and don’t go away, when they are painful, and when they grow, they are usually treated with surgery, such as laparoscopy to remove the tumor. For larger ovarian tumors, surgeons may perform a laparotomy, and if the tumor is malignant (cancerous), the surgeon may selectively remove part or all of the abnormal growth. This process is called ovarian tumor debulking.

Some ovarian tumors are removed while leaving the rest of the ovary intact. Other times the surgeon may remove the entire affected ovary and Fallopian tube. Rarely, both ovaries are removed.

Removing one ovary will not affect the normal function of the remaining ovary. So hormone effects (pubertal change, menstruation) and reproductive capacity of the other ovary should be unaffected.