Home   Chapter Home   Jobs   Conferences   Fellowships   Books



Advertisement

Kidney tumor - cysts, children, adult benign

Benign (usually) adult tumors

Medullary fibroma


Reviewers: Mandolin Ziadie, M.D. (see Reviewers page)
Revised: 28 March 2012, last major update March 2012
Copyright: (c) 2003-2012, PathologyOutlines.com, Inc.

General
=========================================================================

● Usually an incidental tumor
● Also called renomedullary interstitial cell tumor or renal hamartoma
● Multiple medullary fibromas are associated with systemic hypertension

Pathophysiology
=========================================================================

● Medullary interstitial cells regulate intrarenal blood flow, absorption of water and salt and ultimately blood pressure through secretion of prostaglandins

Clinical features
=========================================================================

● Benign
● Usually found incidentally during surgery for other lesions or at autopsy (1 per 700 cases, Pol J Pathol 2008;59:21)

Gross description
=========================================================================

● Small (< 1-5 cm), well-circumscribed, tan-white nodules in the renal medulla / pyramids

Gross images
=========================================================================


   

Multiple lesions in medullary pyramids

Micro description
=========================================================================

● Stellate fibroblast-like cells in a background of loose or dense collagenous tissue with entrapped tubules at periphery

Micro images
=========================================================================


               
Fibroblast-like cells in myxoid or collagenous stroma


Circumscribed fibrogenic lesion among collecting tubules


Small stellate cells, some with vacuolated cytoplasm


Various images

Positive stains
=========================================================================

● Oil Red O, Sudan Black B

Negative stains
=========================================================================

● CD34

Electron microscopy description
=========================================================================

● Resembles renomedullary interstitial cell of kidney with large cytoplasmic lipid droplets (Hum Pathol 1972;3:559)

End of Kidney tumor - cysts, children, adult benign > Benign (usually) adult tumors > Medullary fibroma

Ref Updated: 3/9/12


This information is intended for physicians and related personnel, who understand that medical information is often imperfect, and must be interpreted in the context of a patient's clinical data using reasonable medical judgment. This website should not be used as a substitute for the advice of a licensed physician.

All information on this website is protected by copyright of PathologyOutlines.com, Inc. Information from third parties may also be protected by copyright. Please contact us at copyrightPathOut@gmail.com with any questions (click here for other contact information).