Cardiac fibroma

Abstract

We present a case of cardiac fibroma encountered as an incidental finding at autopsy of an 83-year-old man without a previous clinical symptomatology. Autopsy examination of the thoracic cavity showed an enlarged heart, and a cut along the obtuse margin of the heart revealed a rather well-circumscribed, intramural mass occupying the left ventricle that measured 6×3.5×2.5 cm (Fig. 1a). The external surface was smooth, and the cut surface was hard and gray-white. No hemorrhage or necrosis was identified. The tumor tissue was obtained for both light and electron microscopy. Histologically, the tumor was not encapsulated and was composed mainly of interlacing bundles of dense collagen fibers. A few scattered spindle cells with morphological features of fibroblasts admixed with collagen fibers were recognized (Fig. 1b). The fibroblasts displayed non-atypical features, and mitoses were absent. Immunohistochemically, the cells showed a strong positivity for vimentin, whereas all other markers were negative.At the margin of the tumor, the collagen tissue intermingled with the adjacent myocardial fibers. Elastic fibers that stained red with Verrhoeff-van Gieson stain were also found (Fig. 2a). Upon electron microscopic examination, the tumor was found to be composed of abundant bundles of collagen and elastic fibers. Adjacent to collagen fibers, rare spindle-shaped cells with elongated nuclei were identified (Fig. 2b). Some of the cells had an attenuated cytoplasm but in others, the cytoplasm was more prevalent, and a rich network of rough endoplasmic reticulum was recognized. A basal lamina was not apparent. The elongated nucleus, the abundant rough endoplasmic reticulum, the absence of basal lamina, and the associated extracellular collagen were consistent with fibroblastic differentiation. Fibroblasts and collagen were seen to extend between groups of cardiac muscle fibers at the periphery of the tumor. Cardiac fibromas are rare benign tumors in adults that account for approxi-T. Vougiouklakis ( ✉ ) Fig. 1 a A heart specimen shows an intramural mass located in the left ventricle. b Fibrous conjunctive tissue with rare fibroblasts. Margin of the tumor showing the absence of a capsule and the adjacent myocardial fibers. Hematoxylin and eosin ×100

Sudden Death Due to Infiltration of Left Bundle Branches by Interventricular Septal Cardiac Fibroma

“…However, the richly cellular fibromas were diagnosed mainly in infants or children <10 years of age. We confirmed results that numerous foci of calcification, identifiable with special stains, are found in fibromatous mass, furthermore, in our case numerous elastic fibers were observed beside abundant collagen fibers . Dystrophic calcification of the central portion of the tumor is common, reflecting poor blood supply to the mass.…”

A rare morphology of the cardiac fibroma in a child: a case report

“…Fibroma, which is derived from connective tissue fibroblasts, is the second most common benign primary cardiac tumor in children and is more common in infants under 1 year of age. The most common location is the ventricular septum and free wall of the ventricle, rarely the atrium ( 12 , 13 ). Cardiac myxoma, another common type of cardiac tumors, consists of large numbers of stellate or polygonal myxoma cells with myxoid stroma.…”