Borderline ovarian tumours
A borderline ovarian tumour is a group of abnormal cells in the tissue covering the ovary. Cancer cells typically grow and divide out of control. Doctors may not classify borderline ovarian tumours as cancer because they grow slower and in a more controlled way than cancer cells. They also don’t grow into (invade) nearby tissue like ovarian cancer does. These tumours are also called tumours of low malignant potential.
Borderline ovarian tumours usually develop between the ages of 20 and 40 years old.
Since they grow very slowly, most are stage 1 when they are diagnosed. They are most
commonly found in 1 or both ovaries but can, in rare cases, start in the fallopian
tube or
There are different types of borderline ovarian tumours. The most common types are the following.
Serous borderline tumours can turn into a cancerous ovarian tumour called low-grade serous carcinoma (LGSC).
Mucinous borderline tumours sometimes come back (recur) after treatment as mucinous carcinoma.
Less common borderline ovarian tumours usually develop in only 1 ovary and include:
- endometrioid tumours
- Brenner tumours
- clear cell borderline ovarian tumours
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