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Wilms tumor, also known as nephroblastoma, is the most common malignant kidney tumor in children. It develops when kidney cells begin to proliferate abnormally. Parents often first notice an increase in the size of a child’s abdomen, which at the beginning is usually painless.
The most common signs and symptoms of Wilms tumor include: a palpable abdominal mass, abdominal or back pain, loss of appetite, weight loss, and occasionally fever or blood in the urine. However, many children have no pain or other complaints in the early stages.
If Wilms tumor is suspected, the doctor prescribes diagnostic tests, which usually include ultrasound, computed tomography (CT), or magnetic resonance imaging (MRI), as well as laboratory studies. Only in rare cases is a biopsy of the mass required.
Treatment strategies for Wilms tumor vary somewhat between countries, but both main approaches demonstrate high effectiveness:
European approach: initial (preoperative) chemotherapy, followed by surgery (removal of the affected kidney and examination of lymph nodes), then postoperative treatment depending mainly on the histological subtype (observation, chemotherapy, radiotherapy). This approach achieves treatment success rates of up to 90%.
American approach: initial surgery, followed by postoperative chemotherapy tailored to the histological type and stage of the tumor, with radiotherapy added in some cases. This method, widely used in the USA and Canada, also provides excellent outcomes comparable to the European strategy.
Statistics: Wilms tumor occurs mainly in children under the age of 5 and is very rare in adolescents.
Heredity: The exact causes are not fully understood. In some cases, Wilms tumor is associated with genetic alterations or congenital syndromes.
