Figure 2

Microscopic and immunohistochemical examination of the left axial myxoma. (A) Medium power view showed an acellular to partly cellular proliferation of spindled tumour cells without significant atypia, arranged in variably ring-like structures surrounding small blood vessels with a lymphoplasmacytic infiltrate, embedded in a prominent Alcian-Blue-positive myxoid matrix (inset) (H&E stains). Bar = 200 μm. (B) On high-power view, the tumour cells had oval to spindle nuclei, eosinophilic cytoplasm and indistinct cell borders, and inconspicuous nucleoli, manifesting as so-called ‘myxoma cells’ and ‘lepidic cells’, appearing as short cords or syncytia (H&E stains). Bar = 50 μm. (C) In immunohistochemistry, the myxoma cells were specifically positive for CD31 (lt.) and CD34 (rt.). Bar = 20 μm. (D) Interestingly, a substantial number of these myxoma cells were immunoreactive with GLUT-1 in a cytoplasmic and membranous expression pattern. Bar = 50 μm.