Right atrial myxoma: unusual clinical presentation and atypical glandular histology.

Abstract

A 57-year-old black female presented with a 1-month of right-sided congestive heart failure and clinical evidence of pulmonic and tricuspid valvular stenosis and insufficiency. The echocardiographic examination and ventriculography demonstrated a large right atrial tumor interfering with the function of both right-sided valves. The patient underwent successful surgical resection of the tumor. Histologically, the tumor had cellular areas typical of myxoma, as well as glandular areas, a feature which has been described very rarely in this lesion. Electron microscopy of the glandular zones, which has never been reported previously, shown cells having essential homology with the usual myxoma elements. The atypical histopathology of this lesion supports the theory that atrial myxomas are true neoplasms, and are not derived from unusually organized mural thrombi.

Glandular cardiac myxoma: case report with literature review

“…The dimensions of the myxomas were 5.9 ± 2.0 (range 2.8-9; median 4.8) cm (n = 30). The left atrial myxoma measured 4.9 ± 1.7 (range 1.5-7.8; median 4.5) cm (n = 17) [1, 15, 17, 18, 24, 27, 34, 36-38, 44, 45, 53, 62, 68, 73], and the right atrial myxomas extended 7.6 ± 3.5 (range 2.5-16; median 7.1) cm (n = 10) [4,5,8,12,18,22,24,[39][40][41]58]. The dimensions of the right atrial myxomas were much larger than that of the left (p = 0.0112).…”

“…The weight of the myxoma was reported in 5 patients which was 41.2 ± 38.7 (range 5-109; median 37.5) g (n = 6) [18,22,44,65,68] (1 patient had biatrial myxomas weighed). The myxomas were pedicled in 9 patients [1,22,24,34,36,37,40,68,73], of whom 4 patients had their pedicles measured with a length of 1.5 ± 1.1 (range 0.3-3.0; median 1.3) cm (n = 4); whereas 4 myxomas were broad-based [8,24,39,44]. The attachment site of the myxomas was described in 40 patients, with atrial septum (fossa ovalis) being the most common attached site (Fig.…”

“…The distributions of the glandular structures were expressed in [5,10,21,47,60,68,79], and 4 (7.7%) were widespread/ /extensive [15,24,48,64]. Development of the glandular structures were given in 28 patients: 25 (83.3%) were well-developed [8,12,14,17,21,24,27,36,38,40,43,53,64,65,73,75,79], 1 (3.3%) was very poorly formed [65], 2 (6.7%) had variable structures [22,56] and 2 (6.7%) were pseudo-glands [34,54].…”

“…Histologically, typical myxoma cells are moderate amount of stellate or spindle-shaped myxoma cells, eosinophilic cytoplasm, occasional perivascular aggregates, bubbly to fibrillar stroma with focal haemorrhage, fibrin insudation and haemosiderin-laden macrophages, and absence of nuclear atypia, mitosis, or necrosis [14,22]. Some of these glands contained luminal mucin [14].…”

“…Pathological changes representing differentiations, such as chondrification, calcification, ossification, extramedullary haematopoiesis, thymic remnants and mucin-producing glands occasionally found in CM, indicating a neoplastic origin arising from foregut remnants [76]. Immunohistochemical evidences of indifferentiated mesenchymal cells, non--metastatic nature in most cases [16], gland-like, epithelium-lined cystic and tubular spaces with features of the mesothelioma [22], and ultrastructurally proved active secretional structures [21,23,32] also supported the neoplastic origin theory. Nevertheless, the organising cardiac intramural thrombi and papillary endocardial lesions of histological features similar to those of CM challenged the neoplastic origin hypothesis [64], and the exact origin of CM still remains disputable [3].…”