A child was operated for Wilms tumor partial nephrectomy was done. On HPE nephroblastomatosis tissue was found in the periphery, around tumour. It denotes:- (AIPG 2011)
|A||Mutation in insulin like growth factor|
|B||Possibility of having bilateral enlargement|
|C||Nephroblastoma cell in the lymph node|
|D||Denny Drash syndrome|
a. Nephroblastomas is an uncommon abnormality believed to represent the persistence of embryonal renal tissue.
b. Nephroblastomas has been defined as persistence of metanephric blastema beyond 36 weeks gestation when nephrogenesis ceases or in an inappropriate location or amount before that time. It is of great importance as putative precursor of Wilms tumor being present in less than 1% neonatal necropsies but in 20-40% of kidneys with Wilms tumor.
c. In the neonatal period rests present in two ways either as rare cause of bilateral renal enlargement or as an incidental macroscopic or microscopic postmortem finding, when it should alert the pathologist to the possibility of associated syndrome.
d. Perilobar rests are seen in patient with BWS, hemihypertrophy pseudohermaphroditism, trisomy 18,13 and some familial cases of Wilms tumor.
e. The microscopic appearance of nephrogenic rests and nephroblastomas is often indistinguishable in a biopsy.
f. The precise risk of developing Wilms tumor in each type of rest is unknown but most nephrogenic rests probably do not become neoplastic, particularly those found incidentally.
g. Nephroblastomas in presence of Wilms tumor is usually bilateral and indicates the possibility of bilateral nephroblastomosis, and renal tissue should be conserved whenever possible.