Chemotherapy uses strong drugs to kill fast-growing cancer cells or slow their growth. The main chemotherapy drugs used to treat ovarian cancer are:
- Carboplatin - Carboplatin is one of the most common chemotherapy drugs used for ovarian cancer. It works by causing damage to the genetic material of cells (DNA), which kills them or stops them from dividing. Carboplatin is often given together with another chemotherapy drug called paclitaxel.
- Paclitaxel - Paclitaxel (brand name Taxol) stops cell division by preventing separation of chromosomes during cell division. This means cells cannot complete mitosis and die. Paclitaxel and carboplatin are often used together as an initial (first-line) treatment for ovarian cancer.
- Cisplatin - Cisplatin works in a similar way to carboplatin by damaging DNA to kill cancer cells. It may be used as an alternative to carboplatin in some circumstances, such as if the cancer has come back after initial treatment. Side effects of cisplatin can include nausea, vomiting, numbness or tingling in the hands and feet, and hearing loss.
- Doxorubicin - Doxorubicin stops cell division by interfering with DNA and RNA functions in cancer cells. It can be used alone or combined with other chemotherapy drugs to treat ovarian cancer. Possible side effects include hair loss, mouth sores, nausea, vomiting and low white blood cell counts.
- Topotecan - Topotecan works by inhibiting an enzyme called topoisomerase that is involved in cell replication. This stops cancer cells from dividing and growing. It may be used when the cancer has returned after initial treatment or for women who cannot tolerate other chemotherapy drugs. Side effects can include low blood cell counts, diarrhea, mouth sores, and hair loss.
Targeted Drug Therapies
Targeted drugs are designed to specifically attack cancer cells while doing less harm to normal cells. Several targeted therapies are now used for ovarian cancer drugs:
- Bevacizumab (Avastin) - Bevacizumab works by blocking the formation of new blood vessels (angiogenesis) that tumors need to grow. By cutting off the blood supply to cancerous growths, it inhibits tumor growth and spread. Bevacizumab is often used in combination with chemotherapy as a first- or second-line treatment.
- Olaparib (Lynparza) - Olaparib is a type of targeted therapy called a PARP inhibitor. It works by blocking an enzyme called poly ADP-ribose polymerase that is involved in DNA repair. Without this enzyme, cancer cells have difficulty repairing DNA damage caused by chemotherapy or radiation therapy. Olaparib is approved for patients with genetic mutations in BRCA1 or BRCA2 genes and has shown benefits when used as maintenance therapy after chemotherapy.
- Niraparib (Zejula) - Like olaparib, niraparib is a PARP inhibitor approved to treat advanced ovarian cancer in patients who have responded to platinum-based chemotherapy. It is taken as a pill on an ongoing basis after primary treatment to help maintain remission.
- Rucaparib (Rubraca) - Rucaparib is another PARP inhibitor that has shown effectiveness for recurrent ovarian cancer, particularly in patients with BRCA mutations. It received FDA approval in late 2016 for this use.
Immunotherapy
Immunotherapy harnesses the body's own immune system to fight cancer. For ovarian cancer treatment, the immunotherapy drug that has shown the most promise so far is:
- Pembrolizumab (Keytruda) - Pembrolizumab is a type of immunotherapy called a PD-1 inhibitor. It blocks PD-1 receptors on T cells that normally help keep the immune system in check and allow cancer to avoid detection. By blocking PD-1, pembrolizumab boosts the immune response against cancer cells. It has shown effectiveness as either a single agent or in combination with chemotherapy for advanced ovarian cancer drugs, especially in tumors with high microsatellite instability or mismatch repair deficiency.
Vaccine Therapy
Early research suggests ovarian cancer vaccines designed to stimulate antitumor immune responses may benefit some patients:
- OvaRex MAb - OvaRex is an experimental vaccine made from five tumor-associated antigens commonly found in ovarian cancer cells. It aims to teach the immune system to recognize and attack these cancer antigens. Studies so far show OvaRex can potentially extend remission or survival when given after primary treatment for ovarian cancer in combination with chemotherapy. Larger clinical trials are still underway.
Radiation Therapy
Radiation therapy uses high-energy rays or particles (such as X-rays or protons) to kill cancer cells or slow their growth. For ovarian cancer, radiation is most commonly used:
- After surgical removal of ovarian cancer tumor tissues, to destroy any remaining microscopic cancer cells in the abdomen. This can further reduce the risk of cancer recurrence.
- For advanced cancer that has spread beyond the ovaries, sometimes combined with chemotherapy as palliative treatment to temporarily relieve cancer symptoms from tumor growths in specific areas.
- Rarely, internal or external beam radiation therapy may be used along with chemotherapy as primary treatment before surgery to shrink a large ovarian tumor in order to make surgical removal easier.
With advances in chemotherapy, targeted therapies, immunotherapy, and personalized treatment approaches, the prognosis for ovarian cancer is slowly improving. Emerging treatments hold promise to someday offer more women a chance at long-term remission or even a cure. Ongoing research is still needed to further advance ovarian cancer treatment options.
