Glomus tumors are usually the benign tumor of glomus cells with immunocytochemical and structural features of smooth muscle cells [1]. The majority of cases of glomus tumor are benign but rarely they demonstrate malignant features both clinically and histologically (aka glomangiosarcoma) [2]. Glomangiosarcoma in extracutaneous sites is uncommon but few cases have been reported. Glomangiosarcoma of the heart is extremely rare due to rarity or near absence of glomus bodies in the myocardium. We report a case of glomangiosarcoma with unknown primary lesion but having widespread metastasis in the brain, lung, liver, and the heart.
Discussion:
Most common site for glomus tumor and glomangiosarcoma is dermis and subcutaneous tissue because of the predominance of glomus …show more content…
The solitary tumor is more common in adults while multiple lesions are usually seen in children. One of the case series study on glomangiosarcoma showed that the metastatic rate was 38% in all malignant cases [5]. Histologically the benign glomus tumor has solid nests and sheets of round to polygonal cells interrupted by capillary sized vessels. Glomangiosarcoma can be subdivided into two categories and the basis is whether its origin is from the benign glomus tumor or de-novo. The first type has a malignant component mixed with typical glomus tumor. The malignant counterpart shows atypia and high mitotic index and has increased expression of P53 and bcl-2, not shown by benign glomus tumor cells [6]. On the contrary, de novo glomangiosarcoma is more difficult to diagnose because of the absence of benign glomus tumor histology, and can be easily confused with other sarcomas. Immunostaining is helpful in the diagnosis as tumor cells are typically positive for smooth muscle actin and vimentin but negative for epithelial, vascular and neural markers (i.e. desmin, cytokeratin, S100, chromogranin, and neurofilament)
Discussion:
Most common site for glomus tumor and glomangiosarcoma is dermis and subcutaneous tissue because of the predominance of glomus …show more content…
The solitary tumor is more common in adults while multiple lesions are usually seen in children. One of the case series study on glomangiosarcoma showed that the metastatic rate was 38% in all malignant cases [5]. Histologically the benign glomus tumor has solid nests and sheets of round to polygonal cells interrupted by capillary sized vessels. Glomangiosarcoma can be subdivided into two categories and the basis is whether its origin is from the benign glomus tumor or de-novo. The first type has a malignant component mixed with typical glomus tumor. The malignant counterpart shows atypia and high mitotic index and has increased expression of P53 and bcl-2, not shown by benign glomus tumor cells [6]. On the contrary, de novo glomangiosarcoma is more difficult to diagnose because of the absence of benign glomus tumor histology, and can be easily confused with other sarcomas. Immunostaining is helpful in the diagnosis as tumor cells are typically positive for smooth muscle actin and vimentin but negative for epithelial, vascular and neural markers (i.e. desmin, cytokeratin, S100, chromogranin, and neurofilament)