Cardiac tumors - benign
Mesothelial / monocytic incidental cardiac excrescence

Author: Nat Pernick, M.D. (see Authors page)

Revised: 20 March 2018, last major update November 2013

Copyright: (c) 2007-2018, PathologyOutlines.com, Inc.

PubMed Search: Mesothelial monocytic incidental cardiac excrescence

Cite this page: Pernick, N. Mesothelial / monocytic incidental cardiac excrescence. PathologyOutlines.com website. http://www.pathologyoutlines.com/topic/hearttumorMICE.html. Accessed July 21st, 2018.
Definition / general
  • Benign
  • Incidental finding of endocardium or pericardium during cardiac valve replacement
  • Either reactive or an artifact of surgery (Am J Surg Pathol 1994;18:167), although may exist without prior surgery
Case reports
  • 38 year old woman with metastatic adenocarcinoma involving a mesothelial / monocytic incidental cardiac excrescence (Am J Surg Pathol 1997;21:970)
  • 65 year old man with a case of mesothelial / monocytic cardiac excrescence causing severe acute cardiopulmonary failure (Am J Surg Pathol 2005;29:564)
Microscopic (histologic) description
  • Haphazard mixture of mesothelial cells, histiocytes, fat globules and fibrin
  • Mesothelial cells may form micropapillary or tubular formations
  • No / minimal stroma, no mitotic activity
Microscopic (histologic) images

Images hosted on PathOut server:
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Fat globules, mesothelial cells and histiocytes without stroma

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Positive stains
Differential diagnosis