Wilms Tumor - Childhood: Symptoms and Signs

Approved by the Cancer.Net Editorial Board, 01/2022

ON THIS PAGE: You will find out more about changes and other things that can signal a problem that may need medical care. Use the menu to see other pages.

Children with a Wilms tumor may experience the following symptoms or signs. Symptoms are changes that you can feel in your body. Signs are changes in something measured, like by taking your blood pressure or doing a lab test. Together, symptoms and signs can help describe a medical problem. Sometimes, children with a Wilms tumor do not have any of the symptoms and signs described below. Or, the cause of a symptom or sign may be a medical condition that is not cancer.

Usually, a Wilms tumor is found before it spreads to other parts of the body. A parent or relative may notice a large lump or feel a hard mass in the child’s belly or notice that the belly is much larger than usual. In some cases, a rapid change to a larger diaper size alerts parents to the presence of a tumor. A few children have abdominal pain. However, most of the time, the tumor grows without causing pain, and the child feels and appears healthy.

Frequently, children with a Wilms tumor may have the following symptoms:

  • Blood in the urine

  • High blood pressure

  • Anemia, which is a low level of red blood cells

  • Fatigue

  • A fever that does not go away

If you are concerned about any changes your child experiences, please talk with your child’s doctor. The doctor will ask how long and how often your child has been experiencing the symptom(s), in addition to other questions. This is to help figure out the cause of the problem, called a diagnosis.

If a Wilms tumor is diagnosed, relieving symptoms remains an important part of your child’s cancer care and treatment. Managing symptoms may also be called "palliative care" or "supportive care." Be sure to talk with your child’s health care team about the symptoms your child experiences, including any new symptoms or a change in symptoms.

The next section in this guide is Diagnosis. It explains what tests may be needed to learn more about the cause of the symptoms. Use the menu to choose a different section to read in this guide.