Kidney tumor
Other tumors

Topic Completed: 1 July 2012

Minor changes: 2 July 2020

Copyright: 2003-2019,, Inc.

PubMed Search: Wilms tumor adult renal

Sean R. Williamson, M.D.
Page views in 2019: 2,355
Page views in 2020 to date: 1,657
Cite this page: Williamson SR. Nephroblastoma-adult. website. Accessed August 10th, 2020.
Definition / general
  • Also called Wilms tumor-adult
  • Mean 32 years old, range 21 - 67 years (for patients greater than 18 years old)
  • Criteria for diagnosis: primary renal neoplasm with primitive blastematous spindle or round cell component, abortive or embryonal tubular or glomeruloid structures (i.e., at least biphasic morphology), no renal cell carcinoma or other histology, age 15 years+
Prognostic factors
Case reports
Gross description
  • Large (mean 12 cm), nodular, bulging, grayish white
Gross images

Images hosted on other servers:

Tumor untreated for 5 years

Microscopic (histologic) description
  • Similar to pediatric Wilms with varying amounts of blastema, epithelium and stroma (triphasic)
  • Many "monophasic Wilms" are actually PNET / Ewing
  • Anaplasia is unusual
  • No persistent renal blastema
Microscopic (histologic) images

Images hosted on other servers:

Tubular pattern may resemble pseudorosettes

Triphasic tumor


1: CT scan shows 15 cm tumor of right kidney
2: Grayish yellow lobulated tumor
3a: Large tumor cells exhibit molding
3b: Focal marked pleomorphism
4a: Focal abnormal mitotic figures
4b: Keratin+ squamous epithelium
4c: Focal glomeruloid structures

Positive stains
Negative stains
Molecular / cytogenetics description
  • Associated with 11p15 (Wilms tumor suppressor gene product), isochromosome 7q
  • Adult tumors may have increased genetic complexity compared to pediatric tumors, suggesting a distinct pathogenesis (Virchows Arch 2011;459:547)
Differential diagnosis
  • Clear cell sarcoma of soft parts: nests or short fascicles of spindled or epithelioid cells with clear to granular eosinophilic cytoplasm separated by fibrous septa; S100+, HMB45+, keratin-, t(12;22)(q13;q12)
  • Ewing sarcoma / PNET: rosettes, no blastema, no epithelial structures, CD99+, FLI1+, 90% have EWS / FLI1 fusion product by RT PCR due to t(11;12)(q24/q22;q12)
  • Rhabdoid tumor: rhabdoid type cells; loss of INI1
  • Sarcoma NOS: no epithelium (keratin-)
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