Pediatric cystic nephroma

2021-07-09   Paola Dal Cin , Rita Alaggio 

1.IRCCS Ospedale Bambino Gesú , Roma (Italy)
2.Brigham and Women's Hospital , Harvard Medical School, Boston , MA (USA)

Classification

Definition

Cystic nephromas (CNs) are uncommon benign renal neoplasms affecting children. The existence of clinical, morphological and genetic differences between pediatric and adult CN, supports an independent classification. The presence of cystic nephroma in a child or young adult should alert the clinician to the possibility of a germline mutation in DICER1.

Clinics and Pathology

Epidemiology

Almost exclusively occurs in children younger than 4 years old, most of whom are boys with DICER1 syndrome manifestations OMIM: 60120 1,2.  However, 10% to 20% appears to arise de novo.

Clinical features

Palpable relatively well circumscribed large unilateral abdominal mass incidentally found, but familial forms may present bilaterally 3.

Macroscopic apperances

Poorly encapsulated mass 4

Histopathology

Well delineated, multilocular exclusively cystic neoplasm with absence of immature nephrogenic elements, and variation in septal thickness, variation in cyst size and shape, and degree of pericystic stromal condensation 4.

Immunohistochemistry

Diffuse stromal immunoreactivity for estrogen 5.

Genetics

Mutations

DICER1 mutations in 90% of CN cases , either resulted in premature truncation of the DICER1 protein (deleterious truncating mutations) or involve specific amino acids in the RNase IIIb domain including insertion-deletions with frameshifts, nonsense mutations  6,4,7,5DICER1 mutations have not been found in cystic partially differentiated nephroblastoma 6.

Cytogenetics

Prognosis and treatment

Resection with excellent prognosis if completely excised .

Bibliography

Reference NumberPubmed IDLast YearTitleAuthors
1210367872010Germline DICER1 mutations and familial cystic nephroma.Bahubeshi A et al
2293435572018DICER1 and Associated Conditions: Identification of At-risk Individuals and Recommended Surveillance Strategies.Schultz KAP et al
3316208492019Imaging of DICER1 syndrome.Guillerman RP et al
4267724032016Pediatric cystic nephromas: distinctive features and frequent DICER1 mutations.Cajaiba MM et al
5281779622017Pediatric Cystic Nephroma Is Morphologically, Immunohistochemically, and Genetically Distinct From Adult Cystic Nephroma.Li Y et al
6244810012014DICER1 mutations in childhood cystic nephroma and its relationship to DICER1-renal sarcoma.Doros LA et al
7269252222015Temporal order of RNase IIIb and loss-of-function mutations during development determines phenotype in pleuropulmonary blastoma / DICER1 syndrome: a unique variant of the two-hit tumor suppression model.Brenneman M et al

External Links

Citation

Paola Dal Cin ; Rita Alaggio

Pediatric cystic nephroma

Atlas Genet Cytogenet Oncol Haematol. 2021-07-09

Online version: http://atlasgeneticsoncology.org/solid-tumor/208917/pediatric-cystic-nephroma