Ovarian cancera disease where abnormal cells split without control and spread to other nearby body tissue and/or organs is a type of carcinomacancer arising from tissues that line organs that causes one or more tumours to develop in the ovaries. The ovaries are a pair of small, walnut shaped organs that are responsible for the release of eggs (ovum) during the female reproductive cycle. In general, ovarian cancers are broadly classified into one of three categories depending on the type of cellsthe basic structural and functional unit of all living things they develop from – epithelial, germ-cell or stromal-cell.
Epithelial ovarian cancer is the most common subtype of this disease. It develops from epithelial cells (or epithelium) that form the outer layer of the ovary. Many epithelial ovarian cancers may originate in the fallopian tubes, which connect the ovary to the uterus.
Ovarian cancers are generally diagnosed in women over 50, however, it can affect almost anyone with ovaries – including women, teenagers, transgender men, non-binary individuals, and intersex people – at any age.
Types of Epithelial Ovarian Cancer
Epithelial ovarian cancers can be divided into the following categories based on which type of the epithelium is affected.
Serous Carcinomas
Serous carcinomas are the most common subtype of epithelial ovarian cancers. These cancers develop from the serous membrane of the ovary, which is a thin membrane that lines internal organs. There are two types of serous carcinomas, which are distinguished by tumoura tissue mass that forms from groups of unhealthy cells gradea description of how abnormal cancer cells and tissue look under a microscope when compared to healthy cells.
High-grade serous carcinomas
High-grade serous carcinomas are the most common subtype of this disease. When these tumours are analysed under the microscope, cancer cells appear highly abnormal and with no real structure or pattern. This indicates a high-grade tumour, which is cancer that develops quickly and aggressively. High-grade serous carcinomas are rarely caught early, have high recurrenceto occur or happen again rates, and may have a poorer prognosisto predict how a disease/condition may progress and what the outcome might be.
Low-grade serous carcinomas
Low-grade serous carcinomas are rare, with tumour cells appearing slightly or moderately abnormal. This indicates a low-grade tumour, which are cancers that are slow-growing, and generally less aggressive. Low-grade serous carcinomas are generally found in younger patients, and are less sensitive to chemotherapya cancer treatment that uses drugs to kill or slow the growth of cancer cells, while minimising damage to healthy cells. These tumours are usually less aggressive and may have a better prognosis.
Endometrioid Carcinomas
Endometrioid carcinomas are a rare subtype of epithelial ovarian cancers that are often associated with the condition endometriosis. They often develop with an endometrioma (or chocolate cyst), which develop on the ovary from endometrial tissuea group of cells that work together to perform a function. Endometrioid carcinomas can be slow-growing, and often have a better prognosis than other epithelial ovarian cancers.
Mucinous Carcinomas
Mucinous Carcinomas are rare subtypes of epithelial ovarian cancers that is often detected early. Mucinous cancer cells secrete a thick, protective mucus, which are generally not found in the ovaries. In some cases, this may suggest that this is a secondary cancercancer that has spread from another part of the body, also known as metastasis or mets. When caught early, mucinous carcinomas generally have a good prognosis.
Clear Cell Carcinomas
Clear cell carcinoma is a rare subtype of epithelial ovarian cancer that is often detected early. It may be linked to the condition endometriosis, but this is not always the case. Clear cell carcinomas are often resistant to chemotherapy. While this type of tumour is aggressive, they may have a good prognosis.
Borderline Ovarian Tumours
Borderline ovarian tumours, or ovarian low malignantcancerous, may grow and spread to other areas of the body potential tumours, are a less common subtype of epithelial ovarian tumours that are not classified as a cancer. They develop in the epithelium of the ovary and often grow slower than other forms of ovarian cancer. These types of tumours are often diagnosed early, and are generally diagnosed in adults between the ages of 20-40.
Treatment
If an ovarian cancer is detected, it will be staged and graded based on size, metastasiswhen the cancer has spread to other parts of the body, also known as mets, and how the cancer cells look under the microscope. Stagingthe process of determining how big the cancer is, where it started and if it has spread to other areas and grading helps your doctors determine the best treatment for you.
Ovarian cancers can be staged using the Federation of Gynecology and Obstetrics (FIGO) system from stage I to IV:
- Stage I: cancer cells are confined to one or both ovaries only. This stage is also known as early-stage cancer.
- Stage II: cancer cells have grown deeper into nearby organs in the pelvis, such as the uterus, fallopian tubes, bladdera hollow, muscular sac in the pelvis that stores urine and/or bowelportion of the digestive system that digests food (small bowel) and absorbs salts and water (large bowel); also called intestines. This is also known as localisedaffecting only one area of body cancer.
- Stage III: the cancer has become larger and has spread beyond the pelvis into the lining of the abdomenstomach, stomach area, belly (peritoneumthe membrane that lines the abdominal cavity). Lymph nodessmall bean-shaped structures that filters harmful substances from lymph fluid are also often affected. This is also known as advancedat a late stage, far along or metastatic cancer.
- Stage IV: the cancer has spread to more distant organs, such as the lungs or the liver. This is also known as advanced or metastatic cancer.
Cancers can also be graded based on the rate of growth and how likely they are to spread:
- Grade I: cancer cells present as slightly abnormal and are usually slow growing. This is also known as a low-grade tumour.
- Grade II: cancer cells present as abnormal and grow faster than grade-I tumours. This is also known as an intermediate-grade tumour.
- Grade III: cancer cells present as very abnormal and grow quickly. This is also known as a high-grade tumour.
Once your tumour has been staged and graded, your doctor may recommend genetic testinga procedure that analyses DNA to identify changes in genes, chromosomes and proteins, which can be used to analyse tumour DNA to help determine which treatment has the greatest chance of success, which analyses your tumour DNA and can help determine which treatment has the greatest chance of success. In particular, they may look for mutations in the hereditary breast cancer genes (BRCA1 and BRCA2), which can cause an increased riskthe possibility that something bad will happen in developing ovarian cancer. They will then discuss the most appropriate treatment option for you.
Treatment is dependent on several factors, including fertility, type, stage of disease and overall health.
Treatment options for the epithelial subtype may include:
- Surgerytreatment involving removal of cancerous tissue and/or tumours and a margin of healthy tissue around it to reduce recurrence, potentially including:
- Hysterectomycomplete or partial removal of the uterus.
- Bilateral salpingo-oophorectomyremoval of both ovaries and fallopian tubes.
- Unilateral salpingo-oophorectomyremoval of one ovary and fallopian tube.
- Lymphadenectomysurgical removal of lymph node(s).
- Removal of other organs (only required in some cases where the cancer has spread beyond the pelvis).
- Chemotherapy.
- Targeted therapymedication that targets specific molecular features of cancer cells (usually offered in stages II-IV).
- Radiation therapya treatment that uses controlled doses of radiation to damage or kill cancer cells (rare).
- Clinical trialsresearch studies performed to test new treatments, tests or procedures and evaluate their effectiveness on various diseases.
- Palliative carea variety of practices and exercises used to provide pain relief and improve quality of life without curing the disease.
In patients who have the borderline ovarian tumour subtype, surgery is usually curative and further treatments are usually not required.
Ovarian Cancer Treatment and Fertility
Treatment for ovarian cancer may make it difficult to become pregnant. If fertility is important to you, discuss your options with your doctor and a fertility specialist prior to the commencement of treatment.
Risk factors
While the cause of ovarian cancer remains unknown, the following factors may increase your risk of developing the disease:
- Having a family history of ovarian, breast, uterine and/or bowel cancer.
- A mutation in the BRCA 1 and BRCA 2 genes.
- Having Lynch syndrome.
- Having certain medical conditions such as endometriosis.
- Use of hormone replacement therapymedication that increase the levels of certain hormones in the body (HRT).
- Having a history of tobacco smoking.
- Being obese.
- Reproductive history, including:
- Women who have never had children.
- Women who have had assisted reproduction.
- Women who have had children over the age of 35.
- Having early puberty.
- Having late menopause.
- Having Ashkenazi Jewish ancestry.
Not everyone with these risk factors will develop the disease, and some people who have the disease may have none of these risk factors. See your general practitioner (GP) if you are concerned.
Symptoms
Early-stage ovarian cancer may be asymptomatic. As the cancer progresses, some of the following symptoms may appear:
- Abdominal bloating/swelling.
- Abdominal/pelvic pain and/or pressure.
- Changes in appetite, such as feeling full quickly or not feeling hungry.
- Urinary changes, such as changes in frequency and urgency.
- Changes in bowel habits, such as constipationa condition where a person has difficulty passing faeces/stools and diarrhoeafrequent discharge of watery or loose stools from the body.
- Unexplained weight loss or weight gain.
- Unexplained fatiguea state of extreme tiredness or exhaustion, can be physical or mental.
- Indigestion and/or heartburn.
- Changes in menstrual periods, such as irregular periods, unusual vaginal bleeding, or vaginal bleeding post menopause.
- Pain during sex.
Not everyone with the symptoms above will have cancer, but see your general practitioner (GP) if you are concerned.
Diagnosis
If your doctor suspects you have ovarian cancer, they may order the following tests to confirm the diagnosis and refer you to a specialist for treatment:
- Pelvic examinationa physical exam of the external and internal female pelvic organs.
- Imagingtests that create detailed images of areas inside the body tests, potentially including:
- Pelvic ultrasounda type of medical imaging that uses sound waves to create detailed images of the organs and structures within the pelvis, including the uterus, ovaries, and surrounding tissues.
- Transvaginal ultrasounda type of pelvic ultrasound that involves inserting a device (known as a transducer) into the vagina to produce sound waves and create images of internal female reproductive organs in greater detail.
- CT (computed tomography) scana type of medical imaging that uses x-rays and computer technology to create detailed images of the body.
- PET (positron emission tomography) scana type of medical imaging that uses radioactive tracers to create detailed images of the body.
- Blood teststesting done to measure the levels of certain substances in the blood.
- Biopsyremoval of a section of tissue to analyse for cancer cells.
