Wilms Tumor and WAGR Syndrome

 The condition listed below is associated with WAGR syndrome. Some individuals with WAGR syndrome will have this condition, some will not. Ask your physician whether testing, treatment, or monitoring for this condition is appropriate for your child.

The “W” in WAGR syndrome stands for “Wilms tumor.” See sidebar: What Is Wilms Tumor?

Approximately 50% of children with WAGR syndrome will develop Wilms' tumor.  Periodic screening should begin at birth or upon diagnosis of WAGR syndrome.  Screening for Wilms tumor consists of abdominal ultrasound examinations every 3 months until age 8.  Some physicians also advocate training parents to examine the child’s abdomen between ultrasounds. 


Wilms' tumor in WAGR syndrome tends to occur at an earlier age than in typical children. The average age of diagnosis of Wilms' tumor in children with WAGR syndrome is 17-28 months.  Most cases of Wilms' tumor in children with WAGR syndrome are diagnosed by age 3. In rare cases, Wilms' tumor has been reported in individuals with WAGR syndrome up to age 25. For this reason, some form of monitoring should be continued throughout life, such as ultrasound examinations every 6 to 12 months, and/or observing the child/adult for symptoms such as:


●  A lump or mass in the abdomen

●  Abdominal pain

●  Blood in the urine

●  High blood pressure

●  Fever

●  Diarrhea

●  Weight loss

●  Urogenital infections

●  Anemia

●  Shortness of breath

●  A general feeling of being tired and unwell

●  Nausea and vomiting (these last two are rare)


Diagnosis of Wilms tumor

Wilms tumor may be suspected when a new mass is seen on imaging studies, such as ultrasound, CT, or MRI scan. However, nephrogenic rests (clusters of immature cells in the kidney) are common in children with WAGR syndrome and may be difficult to distinguish from Wilms tumor. Nephrogenic rests are not malignant, but are thought to have potential to become malignant. For more information, see sidebar: Nephrogenic Rests.

Although Wilms tumor may be suspected on imaging studies, definitive diagnosis can be made only on histologic assessment [microscopic study] of the tumor. Approaches to diagnosis, staging of Wilms tumor, and whether/when to biopsy differ:

●       The Children’s Oncology Group [North America] recommends performing nephrectomy/tumor resection and regional lymph node sampling before chemotherapy to obtain the most accurate staging information. If the tumor is deemed unresectable, a biopsy is recommended to confirm the diagnosis [Green 2004, Metzger & Dome 2005].

●       The International Society of Pediatric Oncology (SIOP) [Europe] recommends administering preoperative chemotherapy to all individuals (with or without a biopsy, depending on the individual's age) to shrink the tumor with the aim of facilitating surgery [de Kraker & Jones 2005].

Both of these approaches yield almost equivalent outcomes. In some cases of Wilms tumor in patients with WAGR syndrome, a combination of approaches may be appropriate.


Wilms Tumor Overview, Jeffrey S Dome, MD, PhD and Vicki Huff, PhD. Last Update: September 19, 2013.http://www.ncbi.nlm.nih.gov/books/NBK1294/

Learning about WAGR syndrome: National Human Genome Research Institute, National Institutes of Health (US) Last update: May, 2014. http://www.genome.gov/26023527

WAGR syndrome: a clinical review of 54 cases. Fischbach BV, Trout KL, Lewis J, Luis CA, Sika M. Pediatrics. 2005 Oct;116(4):984-8. http://wagr.org/images/PedReviewArticle2005_54_Cases.pdf

Last updated: February, 2014

Kelly Trout, BSN, RN

Health Consultant

International WAGR Syndrome Association