Site Search:

Syndromes with increased risk of developing Wilms tumor

WAGR syndrome

WAGR syndrome includes several diseases. The W stands for Wilms tumor, theA for Aniridia, the G for abnormalities of the Genitourinary organs, and the R for mental Retardation. These syndromes result from the loss of chromosomal material, several genes from the short arm of chromosome 11. Patients with the WAGR syndrome have a 45% risk of developing a Wilms tumor.

Children with WAGR syndrome are at increased risk of developing renal failure, so their kidney function should be followed closely.

Abdominal ultrasonography should be performed every 3 months to examine the kidneys for the development of a Wilms tumor until at least the age of 8 years.

Aniridia

Aniridia is the absence of the iris (the part of the eye that gives eye its color and controls how much light enters the eye), present at birth. Aniridia results in vision loss, although the amount of vision loss is variable. The gene that causes aniridia is PAX6, which is located near the WT1 gene on chromosome 11p13. Deletions of these neighboring genes (WT1 and PAX6) explain the association between aniridia and Wilms tumor. Patients with aniridia, without the WAGR syndrome, are only at risk for developing Wilms tumor if both the PAX6 gene and the WT1 gene are abnormal.

Patients with aniridia should be seen and tested by a geneticist and an ophthalmologist.

Genitourinary malformation

Genitourinary malformations produce a mixed development of the sexual organs, causing identification of sex to be uncertain, undecended testicles (cryptorchidism), or severe hypospadias. In hypospadias the opening for urine in males is moved from the tip of the penis to the underside of the penis.

Genitourinary abnormalities must be examined by a pediatric urologist.
 

Mental retardation

The intelligence of patients with WAGR syndrome is highly variable. Mental capabilities may be profoundly impaired or may be so close to normal that it is too hard to detect any mental retardation.

Testing for mental retardation should be performed by a developmental specialist.

Parents of children with WAGR have created a support group called Reaching Out, The WAGR Network, and a website: http://www.wagr.org

Denys-Drash syndrome

Denys-Drash syndrome is a rare disorder with only 160 cases reported worldwide. The syndrome includes Wilms tumor, kidney disease, and abnormality of sexual organs (both internal and external). Kidney disease develops 96% of the time between the ages of 2 weeks and 18 months. Almost all children with Denys-Drash syndrome have also been diagnosed with Wilms tumor in one or both kidneys. Denys-Drash syndrome is the result of mutations in the WT1 gene on chromosome 11p13.

All children with signs and symptoms of Denys-Drash syndrome should have an abdominal and pelvic ultrasound to look for the presence of Wilms tumor. In addition, all children should be screened for the presence of abnormal internal genitalia because of their risk of developing gonadoblastoma. The removal of the kidneys and abnormal gonads has been recommended at the time of diagnosis in children with Wilms tumor.

Children with Denys-Drash syndrome should be seen and tested (for the WT1 mutation) by a geneticist.

Beckwith-Wiedemann syndrome

Beckwith-Wiedemann syndrome (BWS) is a an overgrowth syndrome that includes a group of symptoms such as a large tongue (macroglossia), enlarged internal organs (visceromegaly), large body size, a hernia in the umbilical cord (omphalocele), and low blood sugar levels. Most children with the Beckwith-Wiedemann syndrome are very large at birth and have very distinct facial features such as creases behind the ear, an enlarged back of the skull, and a strawberry mark on their forehead and eyelids.

Wilms tumor is the most common cancer in children with BWS, occurring in about 10-20% of all children. Most children develop Wilms tumor before the age of 4 years, and 95% of all Wilms tumor cases have been diagnosed by the age of 8 years.

Children with BWS are also at risk for developing Hepatoblastoma, which is a cancer of the liver.

A blood test called AFP measurement is recommended every 6 weeks, and an abdominal ultrasonography of the liver every 3 months, until the age of 8 years. Liver and renal ultrasonography can be performed at the same time.

Hemihypertrophy

Hemihypertrophy is a rare overgrowth where one side of the body, in whole or in part, is larger than the other side. Therefore, one whole leg or arm may be longer than the other. Wilms tumor has been reported to be found in about 3-5% of the children with hemihypertrophy.