The upregulated expression of proinflammatory cytokines and cytokine receptors is localized to the type-I
glomus cell and is also expressed in the type-II cell and immune cells in the carotid body in sustained hypoxia [15, 29].
Histopathologic section showed skin with the dermis showing a well-circumscribed lesion composed of tight convolutes of mainly thin-walled and occasionally thick-walled, dilated, congested blood vessels of varying sizes surrounded by collars of
glomus cells. These cells were rounded with sharply punched-out, rounded nucleus and a clear to amphophilic cytoplasm.
Histologically, a proliferation of blood vessels surrounded by
glomus cells is seen.
Glomus tumors show abundant dilated, thin-walled blood vessels, are lined by a single layer of endothelial cells, and are surrounded by nests of uniform and round
glomus cells, which are strongly positive for smooth muscle actin and vimentin.
Histopathology examination of typical glomus tumors shows a mixed variable proportion of
glomus cells, smooth muscle cells, and blood vessels [32].
Microscopically, these tumors contain branching vascular channels that are lined with endotheliocytes and interspersed by uniformly round or ovoid
glomus cells. The lesion cells are lightly eosinophilic.
Paragangliomas are rare, generally benign tumors that arise from cells called
glomus cells, which are located along blood vessels and play a role in regulating blood pressure and blood flow.