Cardiac Myxoma

Epidemiology and Etiology:

· Most common primary heart tumour

· Carney Complex (5%)

Common sites:

· Atria (90%)

· Left > R (4:1)

· Fossa ovalis in the atrial septum is favored

Gross features:

· Solitary (almost always)

· <1 to 10cm

· Sessile or pedunculated

· Soft gelatinous to hard

· Hemorrhage maybe

· Papillary or villous maybe

Histologic features:

· Stellate or globular myxoma (“lepidic”) cells

· Endothelial cells

· Smooth muscle cells

· Undifferentiated cells

· Abundant acid mucopolysaccharide

· Endothelialized surface

· Peculiar poorly-formed glandular or vascular structures

· Hemorrhage

· Mononuclear inflammation

Immunophenotype:

Marker:

Sensitivity:

Specificity:

Molecular features:

· Recurrent chromosomal abnormalities of chromsomes:

· 2

· 2p16 in Carney Complex (not in sporadic)

· 12

· 12p1

· 17

· 17p1

· 17q2 in Carney Complex (uncommon in sporadic)

· 1q32

· -Y

· Telomeric association of chromosomes 13 and 15

· Abnormal DNA ploidy patterns may be associated with increased recurrence rate, mostly in familial myxomas

Other features:

· Benign neoplasm

· Symptoms:

· Constitutional symptoms (fever, malaise)

· IL-6 elaboration in some myxomas

· Complications:

· AV Leaflet damage

· Embolization

· Cured by excision usually

· 2-3% recurrence rate for sporadic

· 10-20% recurrence rate in patients with familial myxomas

· May be higher in tumours with abnormal DNA ploidy patterns

References:

· Kumar V, Fausto N, Abbas A. Robbins & Cotran Pathologic Basis of Disease, Seventh Edition. 7th ed. Saunders; 2004.

· Emedicine.medscape.com (2013)