You may find it useful to read this information with our general information about breast cancer.
Phyllodes tumours are rare and most are non-cancerous (benign). They get their name from a Greek word that means 'leaf-like' because they grow in a leaf-like pattern. They are made up of a mixture of cells from connective (fibrous) tissue and the tissue layer (epithelium) that lines the breast.
There are three main types of phyllodes tumour:
- Benign (non-cancerous) tumours make up about 50 to 60% of all phyllodes tumours.
- Malignant (cancerous) tumours make up about 20 to 25% of all phyllodes tumours.
- Borderline tumours are more abnormal than benign tumours, but not quite malignant.
Most benign and borderline phyllodes tumours can be completely cured with treatment.
For people with a malignant tumour, the outlook after treatment is usually very good.
Although phyllodes tumours can affect people of any age, they are more common in pre-menopausal women between the ages of 40 and 50. They usually only affect one breast, although occasionally they can affect both breasts.
It is uncommon for phyllodes tumours to spread to other parts of the body. If they do spread, this is more likely to occur with a malignant tumour. A tumour that has spread to another part of the body is known as a secondary cancer or metastasis.