Wilms Tumor - Childhood: Symptoms and Signs

Approved by the Cancer.Net Editorial Board, 08/2015

ON THIS PAGE: You will find out more about body changes and other things that can signal a problem that may need medical care. To see other pages, use the menu on the side of your screen.

Children with a Wilms tumor may experience the following symptoms or signs. Sometimes, children with a Wilms tumor do not show any of these symptoms. Or, these symptoms may be caused by a medical condition that is not a tumor. 

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 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 Wilms tumor may experience the following symptoms:

  • Blood in the urine 

  • High blood pressure

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

  • Fatigue

  • A fever that doesn’t go away

If you are concerned about one or more of the symptoms or signs on this list, 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 find 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. This may also be called symptom management, palliative care, or supportive care. Be sure to talk with your child’s health care team about symptoms your child experiences, including any new symptoms or a change in symptoms.

The next section in this guide is Diagnosis, and it explains what tests may be needed to learn more about the cause of the symptoms. Or, use the menu on the side of your screen to choose another section to continue reading this guide.