Epithelial Ovarian Cancer: A Detailed Look at Causes, Symptoms, Diagnosis, and Treatments

June 10, 2024

Epithelial Ovarian Cancer: A Detailed Look at Causes, Symptoms, Diagnosis, and Treatments

If you or a loved one has been diagnosed with epithelial ovarian cancer, you may be searching for comprehensive information to help you understand this disease and navigate your journey.

Epithelial ovarian cancer is the most common type of ovarian cancer, accounting for about 90% of all ovarian cancer cases. This cancer develops in the epithelial cells, which form the outer layer of the ovaries. 

Epithelial ovarian cancer can also originate in the fallopian tubes or the peritoneum (the lining of the abdominal cavity). These cancers are often grouped together with ovarian cancer because they share similar features and treatments.

  • According to research, the lifetime risk of developing epithelial ovarian cancer is about 1 in 78 for women in the United States. This means that approximately 1.3% of women will be diagnosed with epithelial ovarian cancer at some point during their lives.

Epithelial Ovarian Cancer Types

There are several types of epithelial ovarian cancer, each with its own characteristics and prognosis:

High-Grade Serous Ovarian Carcinoma (HGSOC)

As the most prevalent subtype, HGSOC accounts for approximately three-quarters of all epithelial ovarian cancers. This aggressive form of cancer is believed to originate in the fallopian tubes and is estimated to take up to six and a half years to reach the ovaries. 

Once it reaches the ovaries, HGSOC rapidly spreads to the peritoneum and other organs. Unfortunately, around 70% of HGSOC cases are diagnosed at an advanced stage (stage 3 or 4), by which time the cancer has already metastasized.

Endometrioid Carcinoma

This subtype frequently occurs in individuals with endometriosis and primarily affects the uterus’s inner lining (endometrium). Compared to other epithelial ovarian cancer subtypes, endometrioid carcinomas generally exhibit a better response to chemotherapy.

Low-Grade Serous Ovarian Carcinoma (LGSOC)

Comprising about 10% of epithelial ovarian cancers, LGSOC is a slow-growing subtype that tends to affect younger individuals, typically between the ages of 40 and 60. Despite its generally better prognosis compared to high-grade serous carcinoma, LGSOC frequently subjects patients to prolonged periods of ineffective therapies and poor quality of life.

Mucinous Carcinoma

These distinct tumors often grow to a substantial size, measuring up to 8 inches (20 centimeters) in diameter. Mucinous carcinomas generally respond well to treatment and are typically confined to the ovaries.

Ovarian Clear Cell Carcinoma (OCCC)

Individuals of Asian descent and those with endometriosis have a higher risk of developing OCCC. This subtype is frequently diagnosed at an advanced stage and exhibits resistance to chemotherapy.

Primary Squamous Cell Carcinoma (SCC) 

SCC usually arises from benign conditions such as ovarian cysts, endometriosis, or Brenner tumors (solid, abnormal ovarian growths). When detected early, SCC responds favorably to treatment.

Borderline Ovarian Tumors (BOT) 

Borderline ovarian tumors (or low malignant potential tumors, or BOTs) account for approximately 15% of all epithelial ovarian tumors. BOTs are characterized by atypical cell growth without invasion into the stromal tissue. Borderline tumors (also called borderline ovarian cancer) commonly affect younger women and have a very good prognosis. Treatment mainly involves surgical removal of the tumor, with chemotherapy rarely being necessary. However, close monitoring is crucial, as recurrences can occur.

It’s essential to recognize that each subtype of epithelial ovarian cancer possesses unique characteristics, and treatment strategies are personalized based on factors such as the cancer stage, grade, and the patient’s overall health.

Risk Factors for Epithelial Ovarian Cancer

Several factors can increase a woman’s risk of developing epithelial ovarian cancer, including:

  • Age: The risk increases as women get older, with most cases occurring after menopause.
  • Family history: Women with a first-degree relative (mother, daughter, or sister) who has had ovarian cancer have an increased risk.
  • Genetic mutations: Inherited ovarian cancer mutations in tumor suppressor genes like BRCA1 and BRCA2 can significantly increase your risk. 
  • Other factors: Obesity, endometriosis, and never having been pregnant may also increase the risk.

Epithelial Ovarian Cancer Symptoms

Early-stage epithelial ovarian cancer rarely causes noticeable symptoms, which is why most cases are diagnosed at advanced stages. However, it’s essential to be aware of your body and pay attention to any persistent changes or symptoms that concern you. As the cancer progresses, women may experience:

  • Bloating or swelling in the abdomen
  • Pelvic pain or pressure
  • Difficulty eating or feeling full quickly
  • Urinary symptoms (urgency or frequency)
  • Fatigue
  • Back pain

If these symptoms persist for more than a few weeks, it’s important to trust your instincts and see a healthcare provider for evaluation. While these symptoms can be caused by other conditions, it’s crucial not to dismiss them. Remember, you know your body best, and advocating for your health is essential. 

It’s also important to note that some women may experience more subtle symptoms or changes in their bodies. These could include:

  • Unexplained weight loss or gain
  • Changes in bowel habits (constipation or diarrhea)
  • Menstrual irregularities (for women who still have periods)
  • Pain during intercourse

If you notice any of these symptoms, don’t hesitate to discuss them with your healthcare provider. They can help determine the cause and recommend appropriate tests or treatments.

Remember, early detection is key to improving outcomes for women with epithelial ovarian cancer. While it can be scary to think about the possibility of cancer, it’s important to prioritize your health and well-being. Trust your instincts, tune in to your body’s signals, and don’t be afraid to seek help when you need it. Your healthcare team is here to support you every step of the way.

Diagnosis of Epithelial Ovarian Cancer

It’s important to note that there is currently no reliable way to screen for ovarian cancer in women who do not have any signs or symptoms. While some tests, such as pelvic exams, ultrasounds, and CA-125 blood tests, may be used to detect ovarian cancer, they have not been proven effective for widespread screening. This is why women must be aware of their bodies and report any persistent symptoms to their healthcare provider.

If you experience symptoms that could be related to ovarian cancer, your healthcare provider will likely start the diagnostic process with the following steps:

  • Pelvic exam: During this exam, your healthcare provider will manually check for any abnormalities in your ovaries, uterus, and other pelvic organs. 
  • CA-125 blood test: This test measures the level of a protein called CA-125 in your blood. Elevated levels may indicate the presence of ovarian cancer, but it’s important to note that other conditions, such as endometriosis or pelvic inflammatory disease, can also cause increased CA-125 levels. The test involves a simple blood draw and can usually be done in your healthcare provider’s office or at a lab.

If the results of these initial tests suggest the possibility of ovarian cancer, your healthcare provider may recommend the following imaging tests:

  • Ultrasound: This test uses sound waves to create images of your ovaries and other pelvic organs. You’ll lie on an exam table, and a technician will apply a gel to your abdomen and move a transducer (a small device that emits sound waves) over your skin. In some cases, a transvaginal ultrasound may be performed, in which a small transducer is inserted into your vagina to get a closer look at your ovaries.
  • CT scan or MRI: These imaging tests provide more detailed pictures of your ovaries and surrounding organs. Both tests usually take 30-60 minutes and may require you to hold your breath for short periods.

Additional Testing

When ovarian cancer is suspected, doctors usually avoid performing incisional or needle biopsies due to the potential risk of causing cancer cells to spread. However, in certain situations, these types of biopsies may be conducted on other parts of the body to determine if the ovarian cancer has spread (metastasized).

If initial tests and examinations indicate the likelihood of ovarian cancer, a surgical biopsy involving the removal of tissue (excisional biopsy) is necessary for confirmation. At this point in the diagnostic process, it is recommended that patients consult with a gynecologic oncologist before undergoing surgery. 

If cancer is confirmed, additional tests, such as PET scans or chest X-rays, may be done to determine the stage of the cancer and whether it has spread to other parts of the body. This information helps your healthcare team develop an appropriate treatment plan.

Throughout the diagnostic process, it’s essential to communicate openly with your healthcare team and ask questions about any concerns you may have. Remember, your providers are there to support you and help you navigate this challenging time with the most accurate information and compassionate care possible.

Treatment Options for Epithelial Ovarian Cancer

Treatment for epithelial ovarian cancer depends on the stage and type of the cancer, as well as the woman’s overall health. The primary goal of treatment is to remove as much of the cancer as possible and prevent its spread. Common treatments include:

Surgery

The first step in treating epithelial ovarian cancer is typically surgery to remove as much of the tumor as possible, a procedure known as debulking surgery. Depending on the extent of the cancer, this may involve removing one or both ovaries, the fallopian tubes, the uterus, and nearby lymph nodes. In some cases, parts of other organs, such as the omentum (a fatty apron that covers the abdominal organs), may also need to be removed.

Debulking surgery aims to leave behind no visible cancer or only small tumors less than 1 cm in size. This is known as optimal debulking and has been shown to improve outcomes and survival rates for women with advanced epithelial ovarian cancer. If optimal debulking is not possible, the surgeon will remove as much of the tumor as safely possible, which is called suboptimal debulking.

Recovery from debulking surgery usually takes several weeks. Women may experience pain, fatigue, and temporary changes in bowel and bladder function.

If you or a loved one has been diagnosed with ovarian epithelial cancer and surgery is being considered as part of the initial treatment plan, it’s crucial to seek care from a gynecologic oncologist. These specialists have extensive training and expertise in managing gynecological cancers, including ovarian cancer. Research has shown that patients who undergo surgery performed by a gynecologic oncologist tend to have better outcomes compared to those treated by other types of surgeons. 

When discussing your treatment options, make sure to ask your healthcare provider about the possibility of being referred to a gynecologic oncologist for your surgical management. Advocating for yourself or your loved one to receive the most appropriate and specialized care can make a significant difference in the overall outcome and quality of life.

It’s important to follow your healthcare team’s instructions for post-operative care and attend follow-up appointments to monitor your recovery.

Chemotherapy

After surgery, most women with epithelial ovarian cancer will receive chemotherapy to destroy any remaining cancer cells. Chemotherapy drugs are typically administered intravenously (through a vein) or intraperitoneally (directly into the abdominal cavity). The most common chemotherapy regimen for epithelial ovarian cancer is a combination of carboplatin and paclitaxel, given in cycles every 3-4 weeks for a total of 6 cycles.

Chemotherapy can cause side effects such as nausea, fatigue, hair loss, and increased risk of infection. Your healthcare team can help you manage these side effects with medications and supportive care. It’s important to communicate any concerns you have about side effects with your team so they can help you find the best solutions.

Targeted Therapy

Targeted therapies are newer drugs specifically targeting cancer cell growth and survival molecules. For example, bevacizumab (Avastin) is a targeted therapy that blocks the growth of new blood vessels that feed tumors. 

Another transformative addition to ovarian cancer-targeted therapy has been the introduction of PARP inhibitors. These medications work by obstructing PARP, a protein vital for repairing damaged DNA within cancer cells, thus impeding their ability to survive and proliferate. They have shown effectiveness, particularly in patients with BRCA mutations, as these mutations make cancer cells more reliant on PARP for DNA repair. PARP inhibitors have expanded treatment options and improved outcomes for many patients with ovarian cancer, offering a targeted therapy approach with potentially fewer side effects compared to traditional chemotherapy.

Targeted therapies are often used in combination with chemotherapy or as maintenance therapy. 

Clinical trials can be a great opportunity to get access to new treatments. Trials provide patients with the opportunity to receive new targeted therapies that could potentially be more effective, but which are not yet widely available. Some patients may experience better outcomes or longer survival rates by participating in clinical trials, especially when standard treatments have been exhausted or are not effective. Always consult with your doctor to discuss the potential benefits and risks of participating in a clinical trial. 

Radiation Therapy

Although radiation therapy is rarely used in the US as the main treatment for ovarian cancer, it is an option for treating ovarian cancer. It uses high-energy radiation to target and kill cancer cells. Radiation therapy is localized to a specific area, targeting the cancer cells within that region. Unlike chemotherapy, which circulates throughout the body and can affect both cancerous and healthy cells, radiation therapy is more targeted, aiming to minimize damage to healthy tissue surrounding the cancerous area. 

This specificity helps reduce side effects and improve the effectiveness of the treatment. Radiation therapy can be used alone or in combination with other treatments like surgery, chemotherapy, or immunotherapy, depending on the individual patient’s condition and the type of cancer being treated.

Your healthcare team will work with you to develop a personalized treatment plan based on your specific diagnosis, medical history, and personal preferences. Don’t hesitate to ask questions and express any concerns you may have about your treatment options. It’s important to feel informed and empowered in making decisions about your care.

Immunotherapy

Immunotherapy is an exciting area of research for ovarian cancer treatment. Immunotherapy works by harnessing the body’s own immune system to target and destroy cancer cells. Several approaches are being investigated, including: 

  • Checkpoint Inhibitors: These drugs target proteins that normally prevent the immune system from attacking cancer cells. By blocking these proteins, checkpoint inhibitors can help the immune system recognize and attack ovarian cancer cells more effectively. 
  • CAR-T Cell Therapy: Chimeric Antigen Receptor (CAR) T-cell therapy involves genetically modifying a patient’s own immune cells to better recognize and attack cancer cells. CAR-T cell therapy has shown promising results in certain blood cancers and is now being explored for solid tumors like ovarian cancer. 
  • Cancer Vaccines: Cancer vaccines are designed to stimulate the immune system to recognize and attack cancer cells. Some vaccines are made from cancer cells or specific proteins found on cancer cells, while others use a patient’s own immune cells that have been modified to recognize cancer cells. 
  • Adoptive Cell Transfer: This approach involves collecting immune cells from a patient, modifying them in the laboratory to better recognize and attack cancer cells, and then reinfusing them back into the patient.

Prognosis and Survival Rates

Important note: Ovarian cancer survival rates have been improving steadily over the years due to advancements in early detection and treatment. While these rates are based on large population studies and serve as a general guide, they don’t necessarily reflect individual situations and they do not definitively predict any one person’s journey with ovarian cancer. 

A gynecologic oncologist should be able to answer the patient’s questions and make a more accurate prognosis. They can also provide a more accurate assessment by taking into account personal circumstances and creating a tailored treatment plan. Factors such as the specific type of ovarian cancer, stage at diagnosis, overall health, and response to treatment all play a role in determining a person’s unique prognosis. With the support of a medical team and loved ones, individuals can navigate this challenging time with strength and resilience.

  • Stage: Women diagnosed with early-stage (stage 1) ovarian cancer have a much better prognosis than those diagnosed at advanced stages (stages 3 or 4). Based on research, the 5-year relative survival rate for women with stage 1 ovarian cancer is about 93%, while it drops to around 75% for stage 3 and 31% for stage 4.
  • Type: Some types of epithelial ovarian cancer, such as endometrioid carcinoma and mucinous carcinoma, tend to have better outcomes than high-grade serous ovarian carcinoma (HGSOC), which is more aggressive and often diagnosed at advanced stages.
  • Other factors: Younger age at diagnosis, good overall health, and optimal surgical removal of the tumors can also improve prognosis.

It’s important to remember that survival rates are based on population averages and may not reflect an individual’s unique situation. Some women with advanced ovarian cancer can have long-term remissions, while others with early-stage disease may experience recurrences. Discussing your specific prognosis with your healthcare team can help you better understand your situation and make informed decisions about your care.

Living with Epithelial Ovarian Cancer

A diagnosis of epithelial ovarian cancer can be overwhelming, but remember that everyone’s journey is unique. It’s essential to tune in to what your body is telling you and trust your instincts throughout this process. Don’t hesitate to ask for help when you need it — your healthcare team, support groups, counselors, and loved ones are all here to help you navigate this challenging time.

As you undergo treatment and cope with the physical and emotional challenges of ovarian cancer, it’s important to treat your body with kindness. Practice self-care by nourishing your body with healthy foods, staying active when possible, and getting enough rest. Be gentle with yourself and acknowledge that some days may be harder than others.

Empowering yourself through body literacy — deepening your understanding of your body’s needs and signals — can be a valuable tool in managing your health. Pay attention to any changes or symptoms you experience, and communicate openly with your healthcare team about your concerns. They can provide guidance and support tailored to your specific situation.

Remember, you are not alone in this journey. There is a community of survivors, advocates, and healthcare professionals ready to offer support, resources, and guidance. Reach out to organizations like Not These Ovaries for information, connection, and empowerment. Together, we can work towards better outcomes and quality of life for all women affected by ovarian cancer.