Heart
Cardiac tumors - benign
Granular cell tumor

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

Revised: 19 March 2018, last major update November 2013

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

PubMed Search: Granular cell tumor heart

Cite this page: Pernick, N. Granular cell tumor. PathologyOutlines.com website. http://www.pathologyoutlines.com/topic/hearttumorgranularcelltumor.html. Accessed July 23rd, 2018.
Definition / general
  • Very rare
  • Usually incidental finding at autopsy that may be overlooked
  • Benign tumor of Schwann cells, not myocytes (Archives 1976;100:276)
  • Only rarely has malignant behavior in heart
Case reports
Gross description
  • Epicardial nodules at base of heart in adults
  • Circumscribed, gray-tan, firm
  • Almost never continuous with nervous tissue
Gross images

Images hosted on PathOut server:
Missing Image

Tumor (arrowheads) overlying
left main coronary artery
near its origin (AO-aorta,
PA-pulmonary artery)
Missing Image

Circumscribed white
tumor of epicardial
surface overlying
right ventricle
Microscopic (histologic) description
  • Tumor cells merge with cardiac myocytes
  • Have ill defined cell margins, abundant eosinophilic and granular cytoplasm with bland pyknotic nuclei, similar to granular cell tumors elsewhere
Microscopic (histologic) images

Images hosted on PathOut server:
Missing Image

Well demarcated tumor
adjacent to coronary artery
(Movat pentachrome stain)
Missing Image

Tumor adjacent to left anterior
descending coronary artery with
arterial elastic fibers highlighted
by Movat pentachrome stain
Missing Image

Tumor has ill defined cell
margins, abundant eosinophilic
and granular cytoplasm
and pyknotic nuclei


Images hosted on other servers:

Esophagus
Missing Image

Clusters of granular cells

Missing Image

PAS and S100

Positive stains
Negative stains
Electron microscopy description
  • Granules are membrane bound autophagic vacuoles with cellular debris
  • May have myelinated and nonmyelinated axon-like structures
Differential diagnosis