Metastatic epithelial ovarian cancer represents a challenging stage of the disease where cancer cells have spread beyond the ovaries to distant parts of the body. Understanding treatment options—from established methods to innovative approaches being tested in clinical trials—can help patients navigate their care journey with greater confidence and awareness of available possibilities.

Understanding Treatment Goals When Cancer Has Spread

When epithelial ovarian cancer reaches a metastatic stage, which doctors also call Stage IV disease, the cancer has traveled from the ovaries to distant organs such as the liver, lungs, or even bones. At this point, treatment focuses on several important goals: controlling the growth of cancer cells, managing symptoms to maintain comfort and quality of life, and extending survival as much as possible. While a cure becomes less likely when cancer has spread this far, many people still respond well to treatment and can experience periods of remission where the disease is controlled.^[2]

Treatment plans for metastatic ovarian cancer depend heavily on where the cancer has spread, how much cancer is present throughout the body, and the patient’s overall health and strength. A person’s age, their ability to withstand intensive treatments, and whether they have other medical conditions all influence which therapies their medical team will recommend. The approach must be personalized because what works well for one person may not be the best choice for another.^[7]

Medical societies and cancer treatment organizations have established standard treatment protocols that combine surgery and chemotherapy as the foundation of care. At the same time, researchers continue to study new medications and treatment combinations through clinical trials. These investigations aim to find more effective ways to fight this aggressive disease, offering hope that tomorrow’s standard treatments will be better than today’s options.^[4]

It’s important to understand that even when cancer has reached distant sites, treatment can often help patients feel better and possibly live longer. Some people with late-stage ovarian cancer survive more than twelve years after treatment, and in medical terms, they are considered cured. While this outcome is not common, it demonstrates that advanced disease does not automatically mean giving up on treatment or hope.^[18]

Standard Treatment Approaches

The cornerstone of treating metastatic epithelial ovarian cancer combines two main approaches: surgery and chemotherapy. Surgery, called cytoreductive surgery or debulking surgery, aims to remove as much visible cancer as possible from the body. During this operation, surgeons typically remove both ovaries, the fallopian tubes, the uterus including the cervix, and any other areas where cancer has spread within the pelvis or abdomen. The goal is to leave behind no visible tumor or the smallest amount of remaining disease possible, as this greatly influences how well chemotherapy will work afterward.^[6]

When cancer has spread extensively or when a patient is not strong enough for major surgery immediately, doctors may recommend chemotherapy first. This approach, called neoadjuvant chemotherapy, works to shrink tumors before attempting surgery. After several rounds of this pre-surgery chemotherapy, if the cancer responds well and becomes smaller, the patient may then undergo cytoreductive surgery, followed by additional chemotherapy. This strategy can make surgery safer and more effective for some patients.^[23]

The standard chemotherapy regimen for epithelial ovarian cancer combines two types of drugs: a platinum-based medication, usually carboplatin, and a taxane-based drug, typically paclitaxel. These medications work by damaging the DNA of cancer cells and interfering with their ability to divide and multiply. The chemotherapy is usually given through a vein in cycles, with treatment days followed by rest periods to allow the body to recover. Most patients receive this combination for six cycles, with each cycle lasting three weeks, though the exact duration depends on how the cancer responds and how well the patient tolerates the treatment.^[13]

About 80 percent of patients initially respond to this first-line chemotherapy, meaning their tumors shrink or disappear on scans and their blood tests improve. However, the challenge with metastatic ovarian cancer is that even after a good initial response, the cancer often returns. The disease typically follows a pattern of remission and relapse, with each period of remission becoming shorter over time as the cancer develops resistance to the chemotherapy drugs.^[16]

For patients whose cancer returns after six months or more following successful initial treatment, doctors may try the same platinum-based chemotherapy again. However, if the cancer comes back within six months or continues growing during treatment, it is considered platinum-resistant. For these patients, different chemotherapy drugs must be tried, though unfortunately, each alternative option generally provides more modest benefits than the original treatment.^[16]

Side effects from standard chemotherapy can include nausea, vomiting, fatigue, hair loss, numbness or tingling in the hands and feet (called peripheral neuropathy), low blood cell counts that increase infection risk, and digestive problems. These effects vary greatly among individuals—some people experience minimal symptoms while others find them quite challenging. Medical teams work to manage these side effects with supportive medications and dose adjustments when necessary.^[1]

Innovative Treatments Being Tested in Clinical Trials

Beyond standard chemotherapy and surgery, researchers are actively studying new types of treatments for metastatic epithelial ovarian cancer. These targeted therapies work differently from traditional chemotherapy—instead of attacking all rapidly dividing cells, they aim at specific molecules or pathways that cancer cells need to survive and grow. Several of these approaches have shown promising results in clinical trials and are changing how doctors treat this disease.^[14]

Targeted Antibody Treatments

One important targeted therapy is bevacizumab, sold under the brand name Avastin. This is a monoclonal antibody—a laboratory-made protein designed to attach to a specific target on cancer cells or in the tumor environment. Bevacizumab targets a protein called VEGF (vascular endothelial growth factor), which tumors use to grow new blood vessels that supply them with nutrients and oxygen. By blocking VEGF, bevacizumab prevents these new blood vessels from forming, essentially starving the tumor. This drug has been approved for use in combination with chemotherapy for patients with newly diagnosed and relapsed ovarian cancer.^[12]

Clinical trials have demonstrated that adding bevacizumab to chemotherapy can improve progression-free survival—the length of time patients live without their cancer growing or spreading further. While the drug doesn’t cure the disease, it can help control it for longer periods. Common side effects include high blood pressure, protein in the urine, bleeding, and in rare cases, problems with wound healing or bowel perforation. Doctors monitor patients carefully while they receive this treatment.^[14]

Another targeted antibody recently approved by the Food and Drug Administration is mirvetuximab soravtansine, marketed as Elahere. This medication represents an exciting advance called an antibody-drug conjugate. It works like a guided missile: the antibody portion seeks out and attaches to a protein called folate receptor alpha, which is found in high amounts on the surface of many ovarian cancer cells but not on most normal cells. Once attached, the antibody delivers chemotherapy directly into the cancer cell, killing it while sparing surrounding healthy tissue. This treatment is approved for patients whose cancer has returned and whose tumors have high levels of folate receptor alpha. In clinical trials, mirvetuximab soravtansine shrank tumors at about double the rate seen with other treatments in this situation.^[14]

PARP Inhibitors

PARP inhibitors represent another major advancement in ovarian cancer treatment. PARP stands for poly (ADP-ribose) polymerase, which is a protein that helps cells repair damage to their DNA. Cancer cells often have defects in other DNA repair mechanisms, making them heavily dependent on PARP to survive. PARP inhibitors block this repair process, causing cancer cells with these DNA repair defects to accumulate so much damage that they die.^[14]

These drugs work particularly well in patients whose tumors have mutations in genes called BRCA1 or BRCA2. Between 10 and 15 percent of epithelial ovarian cancers have these inherited mutations, which impair the cell’s ability to repair DNA damage. When PARP inhibitors are added to the treatment of patients with BRCA mutations, they can significantly delay disease relapse and may even prevent it in some cases. However, PARP inhibitors can also benefit patients without BRCA mutations, especially when used as maintenance therapy after chemotherapy has successfully controlled the cancer.^[16]

Several PARP inhibitors are now approved for use in ovarian cancer, and ongoing clinical trials continue to explore the best ways to use them—whether alone, in combination with chemotherapy, or with other targeted drugs. Side effects can include fatigue, nausea, anemia (low red blood cell counts), and rarely, more serious blood disorders. Researchers are working to understand which patients benefit most from these medications and how to minimize their side effects.^[12]

Immunotherapy Approaches

Immunotherapy treatments work by harnessing the body’s own immune system to recognize and attack cancer cells. While immunotherapy has revolutionized treatment for some cancers like melanoma and lung cancer, it has been more challenging to make it work effectively against ovarian cancer. However, research continues, and some immunotherapy approaches have gained approval for specific situations.^[16]

Checkpoint inhibitors are immunotherapy drugs that release the brakes on the immune system, allowing it to attack cancer more effectively. Two of these drugs, pembrolizumab (Keytruda) and dostarlimab (Jemperli), have been approved for subsets of patients with advanced ovarian cancer. Specifically, they can be used when tumors have certain genetic characteristics called microsatellite instability (MSI-H) or DNA mismatch repair deficiency (dMMR). These genetic features mean the tumor has accumulated many mutations, making it more likely to be recognized and attacked by the immune system when checkpoint inhibitors remove the usual immune brakes.^[16]

Clinical trials are exploring many other immunotherapy strategies for ovarian cancer, including cancer vaccines, adoptive cell therapies where immune cells are modified outside the body and then returned to attack cancer, and combinations of different immunotherapy drugs or immunotherapy with chemotherapy or targeted therapies. While many of these approaches are still experimental, they represent promising directions for future treatment.^[22]

Specialized Chemotherapy Delivery

Some clinical trials are testing innovative ways to deliver chemotherapy directly to where the cancer is located, rather than throughout the entire body. One approach is called hyperthermic intraperitoneal chemotherapy or HIPEC. During cytoreductive surgery, after the surgeon removes all visible tumor, heated chemotherapy is placed directly into the abdominal cavity for a period of time before being removed. The heat helps the chemotherapy penetrate more deeply into any microscopic remaining cancer cells. This intensive treatment is not appropriate for everyone, but in carefully selected patients, it may improve outcomes compared to surgery and standard chemotherapy alone.^[23]

Understanding Clinical Trial Phases

When new treatments are being developed, they go through a series of carefully designed studies called clinical trials. Phase I trials primarily test whether a new drug is safe and determine the appropriate dose to use. They involve small numbers of patients, often those whose cancer has not responded to standard treatments. Phase I trials help researchers understand what side effects might occur and at what doses.^[10]

Phase II trials expand testing to more patients to learn whether the drug actually works against cancer—does it shrink tumors or slow cancer growth? These trials also continue to monitor safety. Phase III trials are large studies that compare the new treatment to the current standard treatment to determine which works better. These trials often involve hundreds or even thousands of patients and take place at multiple hospitals and cancer centers, sometimes in different countries including the United States, Europe, and other regions.^[10]

Patients interested in clinical trials should discuss this option with their cancer care team. Trials offer access to promising new treatments before they become widely available, though they also involve uncertainty since the experimental treatment may not work better than standard care. Trial participants typically receive very close monitoring and follow-up care as part of the research protocol.^[4]

Most Common Treatment Methods

• Surgery (Cytoreductive or Debulking)
  • Removal of both ovaries, fallopian tubes, uterus, and cervix
  • Removal of any visible cancer throughout the pelvis and abdomen
  • Goal is to leave no visible tumor or minimal remaining disease
  • May be performed after initial chemotherapy if cancer is too extensive initially
• Chemotherapy
  • Carboplatin (platinum-based) combined with paclitaxel (taxane-based) as standard first-line treatment
  • Given intravenously in cycles, typically six cycles of three weeks each
  • Neoadjuvant chemotherapy given before surgery to shrink tumors
  • Adjuvant chemotherapy given after surgery to eliminate remaining cancer cells
  • Alternative chemotherapy drugs for platinum-resistant recurrent disease
  • HIPEC (heated chemotherapy placed directly into the abdomen during surgery)
• Targeted Antibody Therapy
  • Bevacizumab (Avastin) blocks blood vessel growth that feeds tumors
  • Mirvetuximab soravtansine (Elahere) delivers chemotherapy directly to cancer cells with folate receptor alpha
  • Used in combination with chemotherapy or alone depending on situation
• PARP Inhibitors
  • Block DNA repair mechanisms in cancer cells, causing them to die
  • Particularly effective in patients with BRCA1 or BRCA2 mutations
  • Used as maintenance therapy after successful chemotherapy response
  • Can significantly delay disease relapse
• Immunotherapy
  • Pembrolizumab (Keytruda) and dostarlimab (Jemperli) for tumors with specific genetic features
  • Checkpoint inhibitors that enable immune system to attack cancer cells
  • Approved for patients with microsatellite instability or DNA mismatch repair deficiency
  • Additional immunotherapy approaches being studied in clinical trials