Symptoms of Wilms tumour

Last medical review:

Wilms tumour may not cause any signs and symptoms in its early stages. Signs and symptoms often appear as the tumour grows and causes changes in the body. For example, a parent or guardian may notice a lump in their childʼs abdomen when changing or bathing them, or a doctor may notice a lump during a routine checkup. Other health conditions can cause the same signs and symptoms as Wilms tumour.

The signs and symptoms of Wilms tumour include:

  • a painless lump in the abdomen
  • swelling of the abdomen
  • blood in the urine (pee) (called hematuria)
  • nausea
  • loss of appetite
  • weight loss
  • an upset stomach or pain in the abdomen
  • constipation
  • fever
  • high blood pressure
  • anemia
  • fatigue
  • shortness of breath or a cough
  • enlarged veins in the scrotum (called varicocele)

Expert review and references

  • Meghan Pike, MD, FRCPC
  • American Cancer Society. Wilms Tumor. 2025. https://www.cancer.org/.
  • Cancer Research UK. Wilms Tumour (Nephroblastoma). 2023. https://www.cancerresearchuk.org/.
  • Cleveland Clinic. Wilms Tumor. 2022. https://my.clevelandclinic.org/.
  • Fernandez CV, Geller JI, Ehrlich PF, et al. Renal tumors. Blaney SM, Adamson PC, Helman LJ (eds.). Pizzo and Pollack's Pediatric Oncology. 8th ed. Wolters Kluwer; 2021: Kindle version, [chapter 24] https://read.amazon.ca/?asin=B08DVWZNVP&language=en-CA.
  • National Comprehensive Cancer Network. NCCN Clinical Practice Guidelines in Oncology: Wilms Tumor (Nephroblastoma) Version 2.2025. 2025. https://www.nccn.org/home.
  • Paulino AC. Medscape Reference: Wilms Tumor. 2024. https://www.medscape.com/.
  • PDQ® Pediatric Treatment Editorial Board. Wilms Tumor and Other Childhood Kidney Tumors Treatment (PDQ®) – Health Professional Version. Bethesda, MD: National Cancer Institute; 2025. https://www.cancer.gov/.
  • PDQ® Pediatric Treatment Editorial Board. Wilms Tumor (PDQ®) – Patient Version. Bethesda, MD: National Cancer Institute; 2025. https://www.cancer.gov/.

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