Ovarian Epithelial Cancer Metastatic
When ovarian cancer spreads beyond the ovaries to distant parts of the body, it becomes metastatic ovarian cancer, classified as Stage IV. This advanced form of the disease represents a significant challenge, yet understanding treatment options and available therapies provides hope for patients and their families.
Table of contents
- What Is Metastatic Ovarian Epithelial Cancer
- Where and How the Cancer Spreads
- Signs and Symptoms
- Diagnosis and Classification
- Treatment Approaches
- Outlook and Survival
What Is Metastatic Ovarian Epithelial Cancer
Metastatic ovarian cancer is cancer that has spread from the ovaries, or the fallopian tubes, to parts of the body outside the site of origin[2]. Ovarian cancer that has metastasized is classified as Stage IV[2].
Epithelial ovarian cancer is the most common type of ovarian cancer, accounting for about 90% of all ovarian cancer diagnoses[3]. It develops in the thin lining that covers the outside of the ovaries, called epithelial tissue[3]. Because of their similarities, medical experts classify fallopian tube cancers and primary peritoneal cancer (cancer that forms in the tissue lining the abdominal wall and organs) as epithelial ovarian cancers and treat them the same way[4].
Epithelial ovarian cancer is one of the deadliest gynecological malignancies. It is typically diagnosed at an advanced stage, complicating treatment and reducing overall survival rates[1]. This type of cancer can be hard to detect because patients may not notice symptoms in early stages[3].
Where and How the Cancer Spreads
There is no single trajectory for where ovarian cancer will spread. However, if not caught in early stages, most cases of ovarian cancer follow a similar path: from the pelvis, to more distant parts of the abdomen and peritoneal cavity (the space inside the abdomen), to the lymph nodes, and the liver[2].
Stage 4 ovarian cancer has spread to distant body parts such as the liver or lungs[6]. It is divided into 2 groups: Stage 4a means the cancer has caused a build up of fluid in the lining of the lungs (the pleura), called a malignant pleural effusion. Stage 4b means the cancer has spread to the inside of the liver or spleen, lymph nodes outside the tummy (abdomen), or other organs such as the lungs[6].
The most common distant organ for ovarian cancer to metastasize to is the liver, followed by distant lymph nodes and the lungs, bones, and brain[7]. As the cancer spreads into the peritoneum, fluid accumulates in the abdomen[3].
Signs and Symptoms
Epithelial ovarian cancer rarely causes symptoms in its early stages. Symptoms become more noticeable as the disease progresses[3]. Only 17% of people with ovarian cancer receive a diagnosis at an early stage, before the cancer has spread[7].
As the cancer spreads into the peritoneum and fluid accumulates in the abdomen, this can cause symptoms like abdominal pain, bloating, difficulty eating or feeling full quickly, nausea and vomiting, and pelvic pain[3].
Less common symptoms include changes in bowel habits, a strong urge to urinate or urinating more frequently, and vaginal bleeding[3].
As the initial tumor grows and cancer cells spread, the number of symptoms can increase. As cancer spreads to other organs, new symptoms can appear[7]. Over 70% of people with an early diagnosis of ovarian cancer say they have pain in the abdomen or pelvis. The pain can be either dull and constant or intermittent and intense[7].
Diagnosis and Classification
Tests that examine the ovaries and pelvic area are used to diagnose and stage ovarian epithelial, fallopian tube, and peritoneal cancers[4]. The stage of a cancer tells you how big it is and if it has spread. The tests and scans you have to diagnose your cancer will give some information about the stage. But your doctor might not be able to tell you the exact stage until you have surgery[6].
There are several subtypes of epithelial ovarian cancer. High-grade serous carcinoma (HGSOC) is the most common and aggressive subtype. It accounts for 3 out of 4 epithelial ovarian cancers. Experts believe HGSOC grows slowly at first. It starts in the fallopian tubes. Once the cancer is in the ovaries, it spreads quickly. Nearly 70% of cases are stage 3 or 4 at the time of diagnosis. This means cancer has spread to nearby organs and lymph nodes[3].
Less common types of epithelial ovarian cancer include endometrioid carcinoma (more common in people who have endometriosis), low-grade serous ovarian carcinoma (LGSOC), mucinous carcinoma, ovarian clear cell carcinoma (OCCC), and primary squamous cell carcinoma (SCC) of the ovary[3].
Treatment Approaches
Treatments for stage 4 ovarian cancer include surgery, chemotherapy, targeted cancer drugs, and radiotherapy[6]. Treatment for this stage of ovarian cancer may include some combination of surgery, chemotherapy, and the targeted medication bevacizumab (Avastin)[18].
Your specialist surgeon (gynaecological oncologist) will remove both ovaries, fallopian tubes, and your womb (including the cervix). They will also check where the cancer has spread to in your pelvis and if it is in your lymph nodes. Your gynaecological oncologist will aim to remove as much of the cancer as possible. This is called cytoreductive surgery. You may also hear it called debulking surgery[6].
You might have chemotherapy after surgery (called adjuvant chemotherapy with cytoreductive surgery), chemotherapy before and after surgery (called neoadjuvant chemotherapy with interval cytoreductive surgery), or chemotherapy into your abdomen during surgery (called hyperthermic intraperitoneal chemotherapy or HIPEC)[6]. Your healthcare team will discuss the best treatment for you. When you have chemotherapy will depend on your individual case[6].
Some people may have treatment with a targeted cancer drug. This will depend on your situation. You might have a targeted cancer drug with chemotherapy, on its own, or after chemotherapy[6].
One of the most investigated and promising molecular targeted drugs in ovarian cancer is bevacizumab, a monoclonal antibody directed against VEGF (a protein that helps tumors grow new blood vessels)[13]. Bevacizumab is used with chemotherapy to treat ovarian cancer recurrence by preventing the growth of new blood vessels that tumors need to grow[14].
Another monoclonal antibody recently approved by the FDA is mirvetuximab soravtansine for people with ovarian cancer recurrence. This drug is used when a person’s cancer was previously treated with at least one systemic therapy to target a protein called folate receptor alpha[14].
PARP inhibitors are drugs that block DNA repair, which may cause cancer cells to die. After completion of upfront chemotherapy, patients may be eligible to receive maintenance therapy with PARP inhibitors, which have been demonstrated to significantly delay and possibly even prevent disease relapse in some patients, particularly patients whose tumor carry mutations in BRCA1 and BRCA2 genes[16].
If it is not possible to have surgery because the cancer has spread widely or you are not well enough, you may have chemotherapy on its own to shrink the cancer as much as possible and to slow its growth. You might have other treatments to help relieve your symptoms. This could be treatment for fluid in the abdomen (ascites) or for a blocked bowel, or radiotherapy to relieve symptoms like pain[6].
You may also be a candidate for clinical trials, which let you contribute to research while trying a new treatment or combination of treatments[18].
Outlook and Survival
Your life expectancy with this type of cancer depends on factors individual to you. Your age, overall health, how well your cancer responds to treatment, and what treatment options are available to you all make a difference in your outcome[18].
Five-year relative survival rates compare the chances that someone with a certain type and stage of cancer will survive for 5 years, compared with the general population. In people who are initially diagnosed with ovarian cancer at stage IV, the 5-year relative survival rate for invasive epithelial ovarian cancer is 31%[7]. Survival rates often improve over time as better treatments become available[7].
Patients who are diagnosed with Stage I and Stage II ovarian cancer have a 5-year survival rate of 90% and 70%, respectively. Patients diagnosed with Stage III ovarian cancer have a 5-year survival rate of 39%[2]. When looking at statistics, it is important to remember that these numbers are representative of a large group of patients, and are not indicative of any one individual’s prognosis[2].
While it’s not common, it’s possible in some cases to cure ovarian cancer even in its advanced stages. Some 20% of those with late-stage ovarian cancer survive more than 12 years after treatment. In medical terms, they’re considered cured[18].
Even when a cure isn’t necessarily the goal, treatments such as pain medication can be used as palliative care to relieve symptoms like pain, fatigue, and digestive issues[18].
