Heart

Benign tumors / other nonneoplastic

Cardiac fibroma



Last author update: 5 January 2023
Last staff update: 5 January 2023

Copyright: 2007-2023, PathologyOutlines.com, Inc.

PubMed Search: Cardiac fibroma

Shuhei Toba, M.D.
Chrystalle Katte Carreon, M.D.
Page views in 2022: 1,164
Page views in 2023 to date: 132
Cite this page: Toba S, Carreon CK. Cardiac fibroma. PathologyOutlines.com website. https://www.pathologyoutlines.com/topic/hearttumorfibroma.html. Accessed January 29th, 2023.
Definition / general
Essential features
  • Second most common primary cardiac tumor in children (34%) but also occurs in adolescents and adults (~40%) (J Thorac Cardiovasc Surg 1994;108:862)
  • Solid, unencapsulated tumor arising predominantly from the ventricles
  • Microscopically consists of bland fibroblasts, varying amounts of collagen and immature mesenchymal cells with little or no atypia and interdigitating / entrapped myocardium (particularly toward the tumor - normal myocardium interface) (JACC Clin Electrophysiol 2019;5:563)
  • Known association with BCNS (Gorlin syndrome)
  • Complete surgical resection may cure ventricular arrhythmias but incomplete removal may result in persistence of arrhythmias (JACC Clin Electrophysiol 2019;5:563)
ICD coding
  • ICD-O: 8810/0 - fibroma, NOS
  • ICD-10: D15.1 - benign neoplasm of heart
  • ICD-11: 2F01 - benign neoplasm of intrathoracic organs
Epidemiology
Sites
Pathophysiology
  • Multinodular architecture of cardiac fibromas suggests a multifocal origin of the tumor arising from proliferation of scattered resident stromal fibroblasts / myofibroblasts interspersed between cardiomyocytes from multiple foci, with progressive nodular growth and subsequent formation of a larger and more compact solid tumor mass (JACC Clin Electrophysiol 2019;5:563)
    • Prominent multilobulation observed in some of these tumors is also consistent with this hypothesis
Etiology
Clinical features
Diagnosis
Laboratory
  • No laboratory findings specific to cardiac fibromas have been reported
Radiology description
  • Cardiomegaly, calcifications on chest Xray (J Thorac Cardiovasc Surg 1994;108:862)
  • Homogenous or heterogenous enhancement on CT (J Thorac Cardiovasc Surg 1994;108:862)
  • MRI (J Am Coll Cardiol 2011;58:1044):
    • Intramyocardial location involving the ventricular septum or free wall
    • Well defined borders with a thin rim of myocardium
    • Strong hyperenhancement on myocardial delayed enhancement (MDE) imaging, with or without hypoenhancing core
    • Hypointense on first pass perfusion (FPP) or magnetic resonance angiogram
    • Heterogeneous appearance on T1 and T2 weighted turbo spin echo (TSE) sequences with variable areas of slightly hypointense or hyperintense areas
Radiology images

Contributed by Stephen P. Sanders, M.D.
MRI (cine SSFP)

MRI (cine SSFP)

MRI (LGE technique)

MRI (LGE technique)

Prognostic factors
Case reports
Treatment
Gross description
Gross images

Contributed by Chrystalle Katte Carreon, M.D. and AFIP
Macroscopic features

Macroscopic features

Cut surface features

Cut surface features

Large septal mass Large septal mass

Large septal mass

Homogeneous mass

Homogeneous mass

Large circumscribed mass

Large circumscribed mass

Frozen section description
  • Intraoperative frozen sections are usually not performed on cardiac fibromas unless there are concerns for malignancy on imaging
Microscopic (histologic) description
  • Bland spindle cell / fibroblastic proliferation with abundant collagen, sometimes immature mesenchymal cells, with little or no atypia (Eur J Med Res 2012;17:5)
  • Cellularity tends to decrease while collagen increases with age (JACC Clin Electrophysiol 2019;5:563)
  • Occasional findings within the tumor include calcification, aggregates of lymphocytes and histiocytes, prominent elastic fibers, extramedullary hematopoiesis, necrosis and ossification (J Thorac Cardiovasc Surg 1994;108:862, JACC Clin Electrophysiol 2019;5:563)
  • Tumor may infiltrate into surrounding myocardium; isolated islands of entrapped myocardium may also be seen
  • Increased mitotic activity or atypia is usually not observed
Microscopic (histologic) images

Contributed by Chrystalle Katte Carreon, M.D.
Abundant collagen

Abundant collagen

Immature appearance

Immature appearance

Entrapped myocardium

Entrapped myocardium

Dystrophic calcifications

Dystrophic calcifications


Lack of tumor capsule

Lack of tumor capsule

Entrapped myocardium (desmin)

Entrapped myocardium (desmin)

Abundant elastic fibers

Abundant elastic fibers


AFIP images
Cellular lesion in infant

Cellular lesion in infant

Collagen deposition

Collagen deposition

Central fibroma cells

Central fibroma cells

Calcification

Calcification


Infiltrative margin

Infiltrative margin

Trichrome

Trichrome

Von Gieson elastin

Von Gieson elastin

Positive stains
Negative stains
Electron microscopy description
  • Fibroblasts with abundant, rough endoplasmic reticulum
  • Intercellular space contains collagen fibers that are regularly banded and arranged in whorls, clustered elastic fibers and ground substance (J Thorac Cardiovasc Surg 1993;106:1208)
Molecular / cytogenetics description
Sample pathology report
  • Heart, left ventricular mass, resection:
    • Cardiac fibroma (4.5 cm) (see comment)
    • Comment: Immunohistochemical stain for desmin shows entrapment of cardiomyocytes within the tumor.
Differential diagnosis
Board review style question #1

Which microscopic feature may be observed in cardiac fibroma?

  1. Extensive necrosis
  2. High mitotic count
  3. Marked atypia
  4. Prominent calcifications
Board review style answer #1
D. Prominent calcifications. Other microscopic features that may be observed in cardiac fibromas include dystrophic calcifications, lymphocytic infiltrate and extramedullary hematopoiesis, among others. High grade features are absent.

Comment Here

Reference: Cardiac fibroma
Board review style question #2
Cardiac fibromas may be a manifestation of which of the following syndromes?

  1. Carney complex
  2. Gorlin syndrome
  3. Holt-Oram syndrome
  4. Tuberous sclerosis
Board review style answer #2
B. Gorlin syndrome, also known as basal cell nevus syndrome (BCNS), is caused by mutations in a tumor suppressor gene called PTCH1. This gene is located on chromosome 9. Mutations in this gene may increase the risk for other tumors, including keratocystic odontogenic tumors, medulloblastomas and ovarian fibromas.

Comment Here

Reference: Cardiac fibroma
Back to top
Image 01 Image 02