Kidney tumours (also called renal tumours) occur when abnormal cells in the kidneys grow in an uncontrolled way.
The most common type of kidney tumour in children is called Wilms tumour (also known as nephroblastoma). Other types of kidney tumours in children include:
- clear cell sarcoma of the kidney
- malignant rhabdoid tumour of the kidney
- mesoblastic nephroma
- renal cell carcinoma.
Wilms tumours are more common in younger children, usually 3–4-year-olds, and less common in older children. In teenagers and young adults, other types of kidney tumours such as renal cell carcinoma are more common.