Nephroblastoma or Wilm’s Tumour Nephroblastoma, although generally rare, is the most common abdominal malignancy among children. Nephroblastoma cells are believed to derive from pluripotent embryonic renal precursor cells. Thus, the condition is linked to the early development of the kidney. Sometimes, the cells that mature and organize into the normal kidney structure remain in their original, primitive form. If these cells begin to multiply after birth, they may ultimately form a large mass of abnormal cells. This is known as nephroblastoma or a Wilms Tumour. It is the most frequently occurring renal tumour in children below the age of 5 years (peak of incidence: 2 years of age). Causes and Symptoms The cause of nephroblastoma is not completely understood. Because 15% of all patients with this type of tumour have other disorders or conditions, due to heredity, it seems apparent that at least some cases of nephroblastoma are due to a hereditary cause. Some patients with nephroblastoma experience abdominal pain, nausea, vomiting, high blood pressure or blood in the urine. However, often parents of children with this type of tumour are the first to notice a firm, rounded mass in their child’s abdomen. Diagnosis and Treatment The physician will order a variety of tests before imaging is performed. These tests mostly involve blood analysis in the form of a white blood cell count, complete blood count, platelet count and serum calcium evaluation. Liver and kidney function testing will also be performed as well as a urinalysis. Initial diagnosis of nephroblastoma is made by looking at the tumour using various imaging techniques. Ultrasound and computed tomography scans (CT scans) are helpful in diagnosing nephroblastoma. Information about the tumour cell type and the spread of the tumour is used to decide the best kind of treatment for a patient. Treatment is usually a combination of surgery, chemotherapy and radiotherapy.