diagnosis methods for ovarian cancer
There is no screening or early detection test available for ovarian cancer. Ovarian cancer is usually detected by a combination of several tests and examinations, including those listed below. The final diagnosis always requires the pathological analysis of a tissue sample, through surgery..
A general check up, including an internal pelvic examination.
A full blood count may be done, as well as a measure of the blood protein CA 125, which is often raised in women with ovarian cancer. CA125 is a protein found in the blood and can be produced by ovarian cancer cells. However, there are other causes for raised CA125 levels such as menstruation, endometriosis or ovarian cysts.
Half of all women with early stage ovarian cancer do not have elevated CA125 levels. The CA125 test is more reliable in postmenopausal women. It is for these reasons CA125 is not recommended as a screening test for women with no symptoms. (Source: Cancer Council)
Other special ‘tumour markers’ may be tested for, but some tumours will not have elevations of these markers and the type of marker depends on the type of tumour.
Ovarian cancer is usually identified by ultrasound or computed tomography (CT) of the abdomen and pelvis, and the CT scene can see if the cancer has spread throughout the body. It should be noted that this is not a definitive diagnosis, and will still require tissue sample collection.
A tissue biopsy is required to diagnose ovarian cancer. This is either done image guided (by ultrasound or CT) or by surgery. The sample is sent to a pathology laboratory where it is analysed under the microscope.
Stages of ovarian cancer
Ovarian cancers can be classified into four stages, depending on the extent of spread of the disease. Staging requires an operation to obtain tissue samples, which are then examined under a microscope.
Stage 1 ovarian cancer
Stage 1 ovarian cancer indicates that the cancer is confined to one or both of the ovaries only. This stage can be divided into more specific groups as below:
Stage 1A: cancer is found in one single ovary
Stage 1B: cancer is found inside both ovaries
Stage 1C: cancer is found inside one or both ovaries and additional cancer cells are present:
- on the outside surface of one or both ovaries; or
- the capsule or outer covering of the ovary has ruptured; or
- cancer cells have been found in the peritoneal cavity fluid (in the abdomen)
Stages 1A and 1B have been identified by researchers as the critical stages that an early detection test must target to ensure maximum effectiveness in improving chances of survival. If patients can be diagnosed at these stages, chances of survival are greater than 90%.
Stage 2 ovarian cancer
Stage 2 ovarian cancer indicates that the cancer is found in one or both ovaries and has also spread into other areas of the pelvis/pelvic tissues.
Stage 3 ovarian cancer
Stage 3 ovarian cancer indicates that one or both ovaries are affected and the cancer is also in the abdominal cavity outside of the pelvis, or there is cancer in nearby lymph nodes, around the aorta, or in the groin. It is also considered to be stage 3 ovarian cancer if it has spread to the surface of the liver.
Stage 4 ovarian cancer
Stage 4 ovarian cancer indicates that one or both ovaries are affected, and the cancer has spread to distant organs beyond the abdomen, such as the tissue inside the liver or lung. If there are cancer cells in the fluid around the lungs, this is also considered to be stage 4 ovarian cancer.
Approximately 70% of all ovarian cancer cases in Australia are diagnosed in Stages 3 or 4, contributing to the low overall relative survival rate of just 46%.
Ovarian cancer survival rates, by stage of diagnosis
Data: Australian Institute of Health and Welfare supplemented by American Cancer Society.
Every year, an estimated 1,800 Australian women are diagnosed with ovarian cancer.
The vast majority of these are at an advanced stage, as there is currently no early detection test, and symptoms are frequently misdiagnosed or not reported. The only way to definitively diagnose ovarian cancer is by taking a tissue sample during surgery.
Raising awareness won’t save lives. In order to save the lives of Australian women, we need to first fund the innovative research that will find an early detection test, and then focus on widespread adoption.
Currently, only 29% of women diagnosed with advanced-stage ovarian cancer will survive beyond five years. But with an early detection test, that would skyrocket to over 90%.
What is ovarian cancer? Signs & Symptoms