Abstract
An autopsy case of malignant hemangiopericytoma in the left thorax in 41 year-old female is presented. The patient first complained of right back pain and dysphagia. Chest X-ray showed well-defined, homogenous mediastinal mass in the left lung field, which rapidly increased in size in a few months. She also had pulmonary tuberculosis. She died with evidence of cardiac failure 8 months after the manifestation of symptoms.
At autopsy the left thorax was filled with a large, gray to light brown, soft mass and the heart and mediastinum were shifted to the right. The left lung was completely replaced by the tumor except for a small portion of the upper hilus. There were residual bronchi passing through the tumor and mucosal involvement of the large bronchi was ascertained.
Microscopically the tumor was composed of tightly packed cells around thin walled, endothelium lined vascular channels, ranging from large gaping sinusoidal spaces to capillaries. The cells were oriented haphazardly and had ovoid or spindle-shaped hyperchromatic nuclei with ill defined cytoplasm. Mitotic figures were almost absent. The flattened endothelial cells lining the gaping sinusoidal vascular structures were separated from the surrounding reticulin meshwork by a basement membrane. Reticulin and collagen fibers also enmeshed the tumor cells outside the vascular channels. Small overt areas of hemorrhages and necrosis were seen.
The metastatic lesions were found in the right lung.
Hemangiopericytoma occurs wherever capillaries were found, however a review of the literature disclosed that cases located in the lung and/or mediastinum are rare.
