Unless ovarian cancer is caught early (and fewer than 2 in 10 cases are), surgery is generally followed by chemotherapy. The goal of chemotherapy, which is usually administered orally or intravenously (IV), is to kill any cancer cells remaining in the body after surgery. Doctors also sometimes use chemotherapy before surgery to shrink very large tumors so that they are easier to remove. Doctors sometimes treat advanced ovarian cancer by using next-generation medicines called targeted drugs. These fight the disease by homing in on traits that distinguish malignant ovarian cells from normal, healthy ones. While radiation plays a role in the treatment of many cancers, it is not typically used for ovarian cancer. Doctors might use radiation to kill cancer cells that have spread beyond the ovaries to areas such as the brain or spinal cord. Hormone therapy, a treatment for some breast cancers, is not generally part of the strategy for fighting ovarian cancer. The exception is a rare type of ovarian cancer called ovarian stromal tumors. (1) RELATED: Large Study Finds No Link Between Use of Talcum Powder in Genital Area and Ovarian Cancer
Ovarian Cancer Surgery: Removing as Much Tumor as Possible
No matter how early doctors diagnose ovarian cancer, surgery is usually part of the treatment plan. Surgery can be extensive if the cancer is advanced and doctors feel the patient is healthy enough in general to withstand the operation. This is true for epithelial ovarian cancer, the most common type of ovarian cancer, as well as for uncommon forms called ovarian germ cell tumors and stromal tumors. One major goal of surgery is staging the cancer to see if it has spread beyond the ovaries. Staging the cancer is essential for helping doctors decide on the best treatment and make a prognosis (a prediction of the course of the disease). Depending on how advanced the cancer is, the surgeon may remove both ovaries and fallopian tubes (a procedure called a bilateral salpingo-oophorectomy) as well as the uterus (an operation called a hysterectomy). Some patients who want to preserve their fertility may have the choice of having an initial surgery that removes only the ovary with the cancer and its adjacent fallopian tube. If a patient has more advanced cancer, surgery will also probably involve removing the omentum, a layer of fatty tissue within the abdomen, as well as lymph nodes in the pelvis and abdomen. Any fluid present in the pelvis or abdominal cavity also has the potential to contain cancer cells, so the surgeon will remove it and send a sample for testing. In addition to staging, surgery to remove as much of an epithelial ovarian tumor as possible — a process called debulking — is a key part of treatment. In order to debulk an ovarian tumor, surgeons may also need to remove a piece of a nearby organ, such as the colon, small intestine, or bladder. Removal of the spleen or gallbladder, as well as parts of the stomach, liver, or pancreas, might also be necessary. Research has shown that surgery that leaves behind no visible cancer or reduces tumor size to 1 centimeter or less has the best outcome. (2) RELATED: Complications of Ovarian Cancer: How Does It Affect Your Body in the Short and Long Term?
Chemotherapy Is Usually Part of the Plan
When found very early, ovarian cancer is usually very treatable and sometimes curable. (3) Women with stage 1 cancers that are deemed low-grade (meaning a tumor sample contains mainly healthy-looking cells) generally don’t receive chemotherapy after surgery. But because ovarian cancer is often detected at later stages, these patients are in the minority. Patients who have advanced disease and those whose disease falls into the most common variety of ovarian cancer (epithelial ovarian cancer) usually receive two different chemotherapy drugs in combination. Typically one drug is a type called a platinum-based compound, usually cisplatin (Platinol) or carboplatin (Paraplatin), while the other is a category of drug called a taxane, such as paclitaxel (Taxol) or docetaxel (Taxotere). These drugs are generally administered in three to six cycles. Other common drugs used to treat ovarian cancer include:
paclitaxel protein-bound (Abraxane)Hexalen (altretamine)capecitabine (Xeloda)cyclophosphamide (Cytoxan)etoposide (Vepesid)gemcitabine (Gemzar)ifosfamide (Ifex)irinotecan (Camptosar)doxorubicin liposomal (Doxil)melphalan (Alkeran)pemetrexed (Alimta)topotecan (Hycamtin)vinorelbine (Navelbine)
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Treatments for Advanced Ovarian Cancer
Some women with advanced ovarian cancer may be candidates for intraperitoneal (IP) chemotherapy, in which Platinol and Taxol are injected into the abdominal cavity through a catheter (thin tube). Patients who might benefit from this treatment are those who have been diagnosed with stage 3 (the cancer has not spread beyond the abdomen) cancer, with tumors that have been “optimally” debulked (meaning they are no larger than 1 centimeter after surgery). IP chemotherapy directs a concentrated dose of drugs to the tumor site. Medication is also absorbed into the bloodstream and can attack cancer cells elsewhere in the body. IP treatment seems to help some patients live longer. But it can also cause more extreme side effects than IV medication, such as abdominal pain, nausea, and vomiting. Researchers are investigating the effectiveness of giving IP chemotherapy during surgery using heated drugs, known as heated intraperitoneal chemotherapy (HIPEC), or “hot” chemotherapy. In this procedure, surgeons remove all visible tumors, then pump chemotherapy medication, which has been heated to 103 degrees Fahrenheit, through the abdominal cavity. Surgeons physically rock the patient on the operating table to make sure the drug reaches all areas of the abdomen. (4) Some research, including one study from 2018, has shown that HIPEC can extend some patients’ lives. (5,6) Women who received HIPEC plus surgery had an overall survival rate of about one year longer than those who only underwent surgery. (7) In November 2022, the FDA approved a new drug to treat certain types of advanced ovarian cancer called mirvetuximab soravtansine-gynx (Elahere). This new drug is an antibody conjugate. It is for some patients who have epithelial ovarian cancer — the most common form. It may also be used for cancers in the fallopian tubes and peritoneum. (8,9) Elahere is approved only for patients with a specific type of ovarian cancer, called folate receptor alpha-positive platinum-resistant disease, who have previously received treatments like chemotherapy, immunotherapy, or hormone therapy. About a third of patients in a clinical trial responded to the treatment. Some saw a decrease in the tumor burden in their bodies, and others had no cancer detected after treatment.
Targeted Therapy: Next-Gen Ovarian Cancer Treatment
Researchers have developed a relatively new type of treatment called targeted therapy that attacks cancer by focusing on traits that the cancer cells need to survive. Instead of killing cancer cells outright, as standard chemotherapy does, targeted drugs interfere with the way these cells function, which can ultimately cause them to die. By zeroing in on cancer cells, targeted drugs avoid harming healthy cells. Patients with advanced epithelial ovarian cancer may be treated with chemotherapy as well as with the targeted drug bevacizumab (Avastin). Avastin attaches to a protein that allows a cancer to develop the new blood vessels it needs to grow. Other targeted drugs, called PARP inhibitors (PARP is an enzyme in cells that helps repair damaged DNA), may be used to treat the small percentage of ovarian cancers linked to mutations in the BRCA gene. These medications may also be used as maintenance therapy (to prevent cancer from recurring after treatment) for patients with or without BRCA gene mutations. PARP inhibitors include olaparib (Lynparza), rucaparib (Rubraca), and niraparib (Zejula). (10)
Immunotherapy: A Promising Approach?
Immunotherapy is a newer approach in treating ovarian cancer. It involves stimulating a person’s immune system so it can better identify and attack cancer cells. Some studies have suggested that combining immunotherapy medication with chemotherapy could offer survival benefits for women with ovarian cancer. (11) Right now, researchers are still studying the effectiveness of this treatment, but it may hold potential down the road. Additional reporting by Julie Marks.
