Kidney tumor
Adult renal cell carcinoma
Tubulocystic carcinoma

Author: Sean Williamson, M.D. (see Authors page)

Revised: 3 February 2017, last major update June 2012

Copyright: (c) 2003-2017, PathologyOutlines.com, Inc.

PubMed Search: Tubulocystic carcinoma kidney

Cite this page: Tubulocystic carcinoma. PathologyOutlines.com website. http://www.pathologyoutlines.com/topic/kidneytumormalignanttubulocystic.html. Accessed February 24th, 2017.
Definition / General
  • Mixture of tubules and micro / macro cysts with low grade nuclear features
  • Also called low grade collecting duct carcinoma, Bellini duct carcinoma
  • Not part of WHO 2004 classification
  • Origin: appears to derive from proximal convoluted tubule and distal nephron
Epidemiology
Clinical Features
  • Often an incidental finding, usually low stage
  • Prognosis is usually excellent with recurrences but only rare distant metastases or death from disease
Case Reports
Gross Description
  • Up to 17 cm, usually well circumscribed, grayish white and cystic ("bubble wrap" appearance), with a medullary location
  • Often surrounded by rim of compressed fibrous tissue
  • Minimal hemorrhage, necrosis or invasion of adjacent renal parenchyma
Gross Images

Images hosted on PathOut server:

Cystic lesion

Micro Description
  • Mixture of closely packed tubules and micro / macro cysts of variable sizes with low grade nuclear features (Urology 1997;50:679)
  • Tubules and cysts are lined by single layer of cuboidal or columnar cells with abundant eosinophilic cytoplasm, uniform nuclei with distinct nucleoli; often have hobnail appearance
  • Overall low grade nuclear features
  • Cysts are closely spaced with variable intervening fibrotic stroma
  • 40% coexist with papillary renal cell carcinoma
  • Minimal mitotic activity, no atypia, no desmoplasia
Micro Images

Images hosted on PathOut server:


Various images


PAS

CK7

CD10

Ki67

Molecular / Cytogenetics Description
Electron Microscopy Description
  • Short microvilli with brush border organization
Differential Diagnosis
  • Multilocular cystic renal cell carcinoma: aggregates of clear cells with atypia within the septae dividing cystic spaces
  • Multilocular renal cyst / cystic nephroma: children under 2 years old and women 40 - 69 years, architecture is predominantly cystic, not tubulocystic; multilocular cysts are lined by flattened or attenuated epithelium with indistinct nucleoli; occasionally hobnail morphology; hyalinized, fibrotic or ovarian-like stroma
  • Mucinous tubular and spindle cell neoplasm: predominantly females, typically long tubular profiles or cordlike growth pattern of uniform, low cuboidal cells with eosinophilic, focally vacuolated cytoplasm and spindling; stroma is myxoid and bubbly with abundant extracellular mucin