Stages and grades of ovarian cancer
Ovarian cancer is diagnosed at one of four stages. The stage describes big a cancer is and how far the cancer has spread inside the body – the higher the stage the further the cancer has progressed. The grade describes how abnormal the cells look under a microscope. Understanding the stage and grade of your cancer can help you and your doctor discuss your diagnosis, treatment and prognosis (the predicted outcome of the disease).
Ovarian cancer is staged according to the FIGO system, named after its authors, the International Federation of Gynaecological Oncologists. There are four ovarian cancer stages.
Stage 1 ovarian cancer
Stage 1 ovarian cancer means that the cancer is contained within one, or both ovaries. At this early stage, the cancer will not yet have started to spread, and surgery will be the main treatment.
Stage 1
ovarian cancer is divided into three groups:
Stage 1A means the cancer is inside only one ovary (or fallopian tube)
Stage 1B means the cancer is inside both ovaries (or fallopian tubes)
Stage 1C is split into a further three groups:
- Stage 1C1 means the cancer is in one or both ovaries (or fallopian tubes) and burst during surgery
- Stage 1C2 means the cancer is in one or both ovaries (or fallopian tubes) and burst before surgery or there is some cancer on the surface of the ovaries (or fallopian tubes)
- Stage 1C3 means the cancer is in one or both ovaries (or fallopian tubes) and there are cancer cells in the fluid taken from around the tummy or pelvis during surgery.
Stage 2 ovarian cancer
Stage 2 ovarian cancer means the cancer has started to spread from the ovaries to other parts of the pelvic region such as the womb, bladder and bowel. The treatment is usually surgery and chemotherapy. Stage 2 ovarian cancer is split into two groups:
Stage 2A means the cancer has spread into the fallopian tubes or womb
Stage 2B means the cancer has spread to other organs in the pelvis, for example the rectum or bladder.
Stage 3 ovarian cancer
Stage 3 ovarian cancer means the cancer has spread beyond the pelvic area into the abdominal cavity (a large space in your abdomen containing organs that include the liver, pancreas and kidneys) or lymph nodes (small glands that form part of a system across the body that help to fight infection and disease). The treatment is surgery and chemotherapy. Stage 3 ovarian cancer is divided into three groups:
Stage 3A is split into two groups:
- Stage 3A1 means the cancer is one or both ovaries (or fallopian tubes) and has spread to the lymph nodes.
- Stage 3A2 means the cancer is one or both ovaries (or fallopian tubes) and spread to the lining of the tummy (peritoneum). The cancer may have also spread to the lymph nodes.
Stage 3C means that there are cancer tumours larger than 2cm on the lining of the tummy (peritoneum). The cancer may also be present in the lymph nodes.
Stage 4 ovarian cancer
Stage 4 ovarian cancer means the cancer has spread to other parts of the body such as the brain, liver or lungs. The treatment is surgery and chemotherapy. Stage 4 ovarian cancer is split into two groups:
Stage 4A means cancer cells are found in the fluid around the lungs
Stage 4B means the cancer has spread to the inside of spleen or liver, or lymph nodes outside from the abdomen, or to other organs such as the lungs.
Ovarian cancer grades
Grading of cancer cells refers to what the cancer cells look like and is used as a prediction of how quickly the cancer will grow and spread. This information help doctors to recommend and plan treatments. For instance, high grade tumours are more likely to respond to chemotherapy than low grade tumours. Like stages, ovarian cancer falls into one of three grades:
- Grade 1 (low grade or well differentiated) ovarian cancer cells look similar to normal cells and grow very slowly
- Grade 2 (moderate or intermediate grade) ovarian cancer cells look more abnormal and grow slightly faster than grade 1 cancer cells
- Grade 3 (high grade or poorly differentiated) ovarian cancer cells look extremely abnormal compared to normal cells and grow quickly in a disorganised way. This is the most aggressive grade of cancer.
Reviewed: Oct 2022
Next review: Jan 2025
