Signs and Symptoms of Wilms Tumors

Wilms tumors occur most often in young children. These tumors often grow quite large before causing any symptoms. Children may look healthy and act and play normally.

Swelling or a large lump in the abdomen (belly)

This is often the first sign of a Wilms tumor. Parents may notice swelling or hardness in the belly while bathing or dressing the child. The lump is sometimes large enough to be felt on both sides of the belly. It’s usually not painful, but it might be in some children.

Other possible symptoms

Some children with Wilms tumor may also have:

  • Fever
  • Nausea
  • Loss of appetite
  • Shortness of breath
  • Constipation
  • Blood in the urine

Wilms tumors can also sometimes cause high blood pressure. This doesn't usually cause symptoms on its own, but in rare cases blood pressure can get high enough to cause problems such as headaches, bleeding inside the eye, or even a change in consciousness.

Many of the signs and symptoms of Wilms tumors are more likely to be caused by something else. Still, if your child has any of these symptoms, check with your child’s doctor so that the cause can be found and treated, if needed.

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Chintagumpala M, Muscal JA. Presentation, diagnosis, and staging of Wilms tumor. UpToDate. Accessed at www.uptodate.com/contents/presentation-diagnosis-and-staging-of-wilms-tumor on August 22, 2018.

Fernandez CV, Geller JI, Ehrlich PF, et al. Chapter 29: Renal Tumors. In: Pizzo PA, Poplack DG, eds. Principles and Practice of Pediatric Oncology. 7th ed. Philadelphia, Pa: Lippincott Williams & Wilkins; 2016.

National Cancer Institute. Wilms Tumor and Other Childhood Kidney Tumors Treatment (PDQ®). 2018. Accessed at www.cancer.gov/types/kidney/hp/wilms-treatment-pdq on August 22, 2018.

Last Medical Review: October 17, 2018 Last Revised: October 17, 2018

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