What Causes Tumors on Your Ovaries?

Ovarian tumors can be noncancerous (benign) or cancerous (malignant). Both benign and malignant tumors can arise from any ovarian tissue, including in the epithelial cells, germ cells, and sex cord or stroma tissue.

• Epithelial ovarian tumors
  • Arise in the ovarian surface epithelium 
  • Mostly benign
• Germ cell ovarian tumors
  • Arise from the primordial germ cells (oocytes)
  • Can be benign or malignant (most are benign)
  • Subtypes are determined by structural differentiation:
    • Extraembryonic differentiation (yolk sac tumor)
    • Somatic differentiation (teratoma)
    • No differentiation (dysgerminoma)
  • Account for less than 2% of all ovarian cancers
• Sex cord and stromal ovarian tumors
  • Arise from the sex cord cells (Sertoli or granulosa cells) or stromal cells (fibroblasts or primitive gonadal stroma)
  • Develop from structural tissue cells in the ovary, which produce the female hormones estrogen and progesterone

Epithelial ovarian cancer is the most common type of ovarian cancer, and it typically affects older women (the median age of diagnosis is 63 years).

Ovarian tumors may not cause symptoms, and symptoms depend on the location and size of the tumor. Symptoms range from stomach pain to endocrinological abnormalities caused by hormone-producing tumors.

Symptoms of tumors on your ovaries may include:

• Nausea and vomiting
• Abdominal bloating or swelling
• Persistent abdominal and pelvic pain
• Constipation
• Frequent urination or urine retention
• Early satiety
• Painful menstrual cramps 
• Menstrual irregularities
• Lower back pain
• Pain during sex
• Vaginal bleeding after menopause

Since ovarian cancer may not cause symptoms in the early stages, detection and diagnosis can be delayed and lead to poor prognosis. Ovarian tumors typically spread intraperitoneally and become apparent later in life due to increased abdominal girth (the distance around the abdomen at a specific point) produced by cancer-related ascites.

Factors that can increase your risk of ovarian tumors include the following:

• Age: Women aged 55-64 have the highest prevalence of ovarian cancer.
• Family history: Risk increases if a mother or sister has had ovarian cancer.
• Mutations in the BRCA1 or BRCA2 genes: These genetic mutations increase the risk of ovarian cancer considerably.
• Obesity: If you have a body mass index of 30 kg/m2 or more, you may be at higher risk
• Nulliparous or late pregnancy: Women who have never conceived and carried a pregnancy or who had a pregnancy after age 35 are at higher risk.
• Fertility medications and hormone therapies: Continuing to take estrogen after menopause may increase the risk of developing ovarian cancer.

Treatment of ovarian tumors depends on the symptoms present. Benign ovarian tumors can be treated conservatively. Most ovarian cysts do not produce major symptoms, dissolve on their own, and do not require surgical intervention.

If these approaches fail and the tumor grows or causes discomfort or cancer is suspected, your doctor may suggest surgery and chemotherapy.

• Surgery: Ovarian cysts that cause discomfort must be surgically removed. Ovarian neoplasms that continue to develop will also require surgery. If the preoperative risk assessment indicates a low probability of cancer, ovarian-sparing surgery (ovarian cystectomy) is performed to remove only the mass or tumor, leaving the rest of the ovary intact. The whole ovary is removed if ovarian cancer is suspected based on pelvic imaging or ovarian tumor markers.
• Chemotherapy: Chemotherapy drugs can inhibit the ability of cancer cells to grow or replicate. Typically, chemotherapy is administered before surgery to decrease the size of the tumor, making it easier to remove. It may also be administered after surgery to kill any remaining cancer cells and prevent a recurrence. Chemotherapy can be administered in the following ways:
  • Orally in pill form
  • Injections:
    • Intramuscularly (injection into muscle tissue or fat tissue)
    • Intravenously (injection into the bloodstream)
    • Intrathecally (injection into the spinal column)

Although ovarian cancer cannot necessarily be prevented, you may be able to reduce your risk by making lifestyle changes, such as:

• Eating a healthy diet rich in whole, natural foods
• Reducing your intake of processed and refined foods
• Exercising regularly
• Maintaining a healthy weight
• Quitting smoking
• Taking birth control pills