Editing Pediatrics: Renal and Adrenal Oncology (section)

==== History and Physical Exam ====
* '''Classically presents with a palpable mass or gross hematuria but abdominal pain and hypertension can also be present'''
** '''<span style="color:#ff0000">> 90% have an asymptomatic abdominal mass discovered incidentally</span>''' by a family member or physician
*** '''Abdominal mass may be firm, non-tender and classically does not cross the midline (neuroblastoma can cross midline)'''
*** '''Other symptoms include fever, anorexia, and weight loss in 10% of patients'''
*** Rarely, children may have acute abdominal pain from tumor rupture into the peritoneal cavity or bleeding within the tumour.
** '''<span style="color:#ff0000">≈20% have hematuria at diagnosis'''
*** '''Gross hematuria warrants further evaluation to rule out tumor extension into the collecting system'''
** '''<span style="color:#ff0000">≈25% have hypertension at diagnosis'''
*** Hypertension can be caused by elevated plasma renin levels
* Compression or invasion of adjacent structures may result in an atypical presentation. A persistent varicocele in the supine position or hepatomegaly may be reflective of inferior vena cava obstruction from tumor thrombus
*Aniridia
**
** Found in 1% of Wilms tumor patients
** Caused by an abnormality of the PAX6 gene located adjacent to the WT1 gene
*** A deletion of chromosome 11 has been found most frequently in Wilms tumor patients with aniridia
*'''The development of a renal tumor in a child known to have aniridia, hemihypertrophy, or other syndromes associated with an increased incidence of nephroblastoma is most likely to be a Wilms tumor.'''
*'''Genitourinary anomalies (renal fusion anomalies, cryptorchidism, hypospadias) are present in 4.5% of patients with Wilms tumor'''
** '''May be associated with horseshoe kidney'''
** '''Increased risk of Müllerian duct anomalies in girls with Wilms tumor'''