Ovarian Cancer Treatment Options

Chemotherapy drugs are given during the ovarian cancer treatment process to kill the cancer cells. The timing of chemotherapy is dependent on the stage of the ovarian cancer. It can be given before surgery, after surgery, or both.

Chemotherapy for ovarian cancer can be given in different ways:

• By vein (IV): The drugs can be given through a thin tube inserted into a vein.
• Intraperitoneal (IP): Chemotherapy that is given directly into the abdomen.
• Combination of vein and directly into the abdomen: Some women get IV chemotherapy combined with intraperitoneal (IP) chemotherapy.
• By mouth: Some drugs for ovarian cancer can be given by mouth.

Targeted therapy is a special type of chemotherapy that uses drugs or other substances to identify and attack specific cancer cells, rather than all cells like traditional chemotherapy. Because this treatment specifically seeks out cancer cells, normal cells are less likely to be damaged.

While each type of targeted therapy works differently, they all alter the way cancer cells grow, divide, repair, and interact with other cells.

Monoclonal antibody therapy is a type of targeted therapy in which the antibodies attach to the substances and kill cancer cells, block their growth, or keep them from spreading.

Bevacizumab is a monoclonal antibody that may be used with chemotherapy to treat ovarian epithelial cancer, fallopian tube cancer, or primary peritoneal cancer that has recurred. This drug starves the cancer cells of the blood supply they need to grow. It is approved for newly diagnosed or relapsed ovarian cancer patients and can be used in combination with chemotherapy.

Poly (ADP-ribose) polymerase inhibitors (PARP inhibitors) are targeted therapy drugs that block DNA repair and may cause cancer cells to die. PARP inhibitor therapy is being studied in treating ovarian epithelial cancer that remains after chemotherapy.

Therapies may be used in different combinations depending on the stage of cancer and the health of the patient. Targeted therapy may be prescribed as oral pills or administered intravenously.

As mentioned earlier, radiation therapy is rarely used in the initial treatment of ovarian cancer, but it is continuously being researched for use as a standard form of treatment. Sometimes, radiation may be used to relieve pain and other problems caused by the disease. It may also be used to treat small, localized recurrent cancer. The treatment is given at a hospital or clinic. Each treatment takes only a few minutes.

Although radiation therapy isn’t used as often, it is being tested more frequently in clinical trials in hopes of becoming another treatment option for ovarian cancer.

Immunotherapy is a type of cancer treatment that uses our body's immune system to recognize, target, control, and eliminate certain types of cancer cells.

Immunotherapy drugs help the immune system:

• Detect and attack cancer cells while leaving healthy cells intact
• Adapt to changes in the cancer, re-evaluate, and launch a new attack
• “Remember” the cancer cells, target and kill them if cancer recurs
• Boost immune cells to maximize their cancer-fighting ability

Oncologists might recommend immunotherapy for patients with resistance to chemotherapy, with recurrent ovarian cancer, or with ovarian cancer Stage 2 or higher.

Currently, Pembrolizumab, an immune checkpoint inhibitor, is approved to block the production of PD-1 protein. This protein reduces the body’s natural ability to recognize foreign substances, like cancer cells. By blocking PD-1 from overproducing, the body can identify cancer cells and use the immune system to attack and kill them. 

Hormone-blocking drugs, called hormone therapy, are not often used for epithelial ovarian cancer, which is the most common type of ovarian cancer.  It is used more often in treating a different kind type of ovarian cancer known as an ovarian stromal tumor.

Luteinizing-hormone-releasing hormone (LHRH) agonists

Also known as GnRH agonists, these hormone-blocking drugs shut down estrogen production from the ovaries. They are used to lower estrogen levels in premenopausal women. Examples are goserelin and leuprolide, which are given by injection every 1 to 3 months. Side effects can include menopause symptoms like hot flashes and vaginal dryness. Long-term use may weaken bones, possibly leading to osteoporosis.

Tamoxifen

Often used to treat hormone-positive breast cancer, tamoxifen aims to block estrogen's cancer-stimulating effects. Some women experience vaginal dryness and hot flashes while taking tamoxifen. Unlike some treatments, it does not cause bone loss but increases the risk of blood clots in the legs.

Aromatase Inhibitors

Aromatase inhibitors block an enzyme that converts other hormones into estrogen in postmenopausal women. These drugs are used for breast cancer but also to treat recurring ovarian stromal tumors and low-grade serous carcinomas. Examples are letrozole, anastrozole, and exemestane, which are taken daily as pills.

Side effects of this treatment include joint pain, hot flashes, muscle pain, and bone thinning, which can lead to fragile bones and osteoporosis.