Kidney tumor
Childhood tumors
Nephroblastoma cystic partially differentiated
Topic Completed: 1 June 2017
Minor changes: 1 July 2020
Copyright: 2003-2019, PathologyOutlines.com, Inc.
PubMed Search: Cystic partially differentiated nephroblastoma [title]
Related topics: Wilms tumor of children
Table of Contents
Definition / general | Essential features | Epidemiology | Radiology images | Case reports | Treatment | Gross description | Gross images | Microscopic (histologic) description | Microscopic (histologic) images | Positive stains | Molecular / cytogenetics description | Differential diagnosisCite this page: Rollins M, Ellis C. Nephroblastoma cystic partially differentiated. PathologyOutlines.com website. https://www.pathologyoutlines.com/topic/kidneytumorcysticnephroblastoma.html. Accessed January 24th, 2021.
Definition / general
- WHO: multilocular, exclusively cystic neoplasm of very young children, containing nephroblastomatous tissue (Moch: WHO Classification of Tumours of the Urinary System and Male Genital Organs (IARC WHO Classification of Tumours), Fourth Edition, 2016)
Essential features
- Entirely multilocular cystic tumor (no expansile masses or solid areas within the tumor)
Epidemiology
- Occurs in children (boys > girls), usually < 2 years of age (Amin: Diagnostic Pathology - Genitourinary, Second Edition, 2016)
Radiology images
Images hosted on other servers:
Ultrasonography of a large multi-cystic lesion
CT showing abdominal distension
T2 weighted image of a renal mass
Case reports
- 1 year, 5 month old boy with cystic tumor (Indian J Pathol Microbiol 2010;53:831)
- 1 year, 6 month old boy with bilateral abdominal masses (Urology 2016;92:106)
- 2 year old girl with gradually increasing painless abdominal mass (Indian J Nephrol 2013;23:460)
- 4 year old boy with abdominal mass (J Postgrad Med 2006;52:45)
- 45 year old man with multicystic right renal mass (Int J Clin Exp Pathol 2015;8:989)
Treatment
- Children's Oncology Group (COG) recommends resection with no further therapy (Amin: Diagnostic Pathology: Genitourinary, Second Edition, 2016)
- The International Society of Paediatric Oncology (SIOP) recommends chemotherapy before resection since imaging is not definitive (Amin: Diagnostic Pathology: Genitourinary, Second Edition, 2016)
- The World Health Organization reports that surgery is always curative and that stage 1 patients are cured without neoadjuvant chemotherapy (J Pediatr Surg 2003;38:897, J Urol 2007;177:294)
- Rare recurrences have been reported as complications of incomplete resection (Cancer 1989;64:466) or tumor rupture (Pediatr Blood Cancer 2008;50:129)
Gross description
- Typically a large multicystic tumor (mean diameter of 10 cm), with no expansile or solid areas
Gross images
Images hosted on other servers:
Numerous thin walled cysts
Cystic nephroma specimen
well circumscribed multicystic lesion
multicystic tumor
Microscopic (histologic) description
- Cysts lined with flat / cuboidal / hobnail cells (or are denuded)
- Epithelial elements consist mainly of mature and immature tubules and small papillae resembling immature glomeruli
- Key histological findings of the variably cellular septa include:
- Nephroblastomatous epithelial elements (J Urol 2010;183:1585)
- Islands of undifferentiated blastema and differentiated mesenchymal elements (skeletal muscle and less often cartilage and fat, J Urol 2010;183:1585)
- Focally, the septal elements may protrude into the cystic spaces in microscopic papillary folds
Microscopic (histologic) images
AFIP images
Embryonal elements are present
Images hosted on other servers:
Cysts with hobnail epithelium
Various images
H&E
WT1
Positive stains
- WT1: blastemal cells
Molecular / cytogenetics description
- Hyperdiploidy and trisomy 12: trisomy 12 was the only chromosomal anomaly common to all four studied cases (Hum Pathol 1996;27:980)
Differential diagnosis
- Cystic renal dysplasia:
- Usually diffuse and bilateral, typically obstructive symptoms are present clinically, presence of primitive ducts on histology (Arch Pathol Lab Med 2015;139:547)
- Pediatric cystic nephroma:
- Exclusively cystic renal neoplasm, however the septae do not contain nephroblastomatous elements
- Pediatric cystic nephroma does not contain ovarian type stroma and is associated with DICER1 mutations, not found in cystic partially differentiated nephroblastoma
- Wilms Tumor:
- Solid Wilms tumor with multifocal cystic change has predominately solid areas containing focally cystic areas, and has malignant behavior
- In contrast, cystic partially differentiated nephroblastoma is predominantly cystic with blastemal or other embryonal cells in the septa of the cysts; it lacks nodular solid regions
- Both are WT1+
