Cases
70-year-old woman with left atrium mass   

Discussion

Papillary fibroelastoma

Pathophysiology

Papillary fibroelastomas are uncommon benign tumors of the endocardium; their pathophysiology is not entirely known. They sometimes exhibit a surface lamination, consistent with the concept of growth by successive organization of fibrin deposits. The papilliferous surface is considered to result from exposure to the hemodynamic stress of flowing blood.

Epidemiology

Papillary fibroelastoma is the most common primary tumor of the cardiac valves and the third most common primary cardiac tumor overall. Most are diagnosed between the fourth and eighth decades of life. They are slightly more common in men.

Clinical presentation

They are mostly found incidentally on echocardiography. Symptoms are usually a consequence of embolus formation.

Imaging and macroscopic findings

Echocardiographic characteristics include endocardial-based lesions with stalk attachment, high mobility, and a refractive appearance. A peripheral “shimmer,” commonly seen on a transesophageal echocardiogram, is very suggestive of the lesion. Submerging the lesion grossly in clear liquid makes fronds more apparent. They have a "sea anemone" appearance grossly.

Microscopic features

In typical histological presentation, avascular fronds consisting of collagen and elastic fibers lined on the surface with endothelial cells are seen. The papillae are not fine or branching. A cardiac myxoma contains myxoma cells and typically lacks fine papillae. Immunohistochemically, the tumor cells express markers of endothelial differentiation, including CD31, CD34, and factor VIII, which highlight the endothelial lining. Special stains, such as Verhoeff-van Gieson elastic staining, stain elastic fibers within papillary fronds.

References

  1. Mariscalco G, Bruno VD, Borsani P, Dominici C, Sala A. Papillary fibroelastoma: Insight to a primary cardiac valve tumor. J Card Surg. 2010;25(2):198-205. doi:10.1111/j.1540-8191.2009.00993.x.
  2. Gowda RM, Khan IA, Nair CK, Mehta NJ, Vasavada BC, Sacchi TJ. Cardiac papillary fibroelastoma: A comprehensive analysis of 725 cases. Am Heart J. 2003;146(3):404-410. doi:10.1016/S0002-8703(03)00249-7.
  3. Klarich KW, Enriquez-Sarano M, Gura GM, Edwards WD, Tajik AJ, Seward JB. Papillary fibroelastoma: Echocardiographic characteristics for diagnosis and pathologic correlation. J Am Coll Cardiol. 1997;30(3):784-790. doi:10.1016/s0735-1097(97)00211-8.
  4. Sun JP, Asher CR, Yang XS, et al. Clinical and echocardiographic characteristics of papillary fibroelastomas: A retrospective and prospective study in 162 patients. Circulation. 2001;103(22):2687-2693. doi:10.1161/01.cir.103.22.2687.
  5. Saad RS, Galvis CO, Bshara W, Liddicoat J, Dabbs DJ. Pulmonary valve papillary fibroelastoma. A case report and review of the literature. Arch Pathol Lab Med. 2001;125(7):933-934. doi:10.1043/0003-9985(2001)125<0933:PVPF>2.0.CO;2.