Tumors O F Blood Vessels

Tumors of the blood vessels are perhaps as common as any form of neoplasm occurring in the human body. The greatest number of these lesions are benign angiomas of the body surfaces, small elevated red areas which remain without symptoms throughout life and are not subjected to treatment. Larger tumors of this type which undergb active growth after birth o r which are situated about the face or oral cavity, where they constitute cosmetic defects, are more often the object of surgical removal. The majority of the vascular tumors clinically or pathologically studied fall into this latter group. Benign angiomas of similar pathologic nature occur in all of the internal viscera but are most common in the liver, where they are disclosed usually a t autopsy. Angiomas of the bone, muscle, and the central nervous system are of less common occurrence, but, because of the symptoms produced, a higher percentage are available f o r study. Malignant lesions of the blood vessels are fa r more rare than was formerly supposed. An occasional angioma may metastasize following trauma or after repeated recurrences, but less than 1 per cent of benign angiomas subjected to treatment fall into this group. I Primarily malignant tumors of the vascular system-angiosarcomas-are equally rare. The pathological criteria for these growths have never been adequately established, and there is no general agreement as to this particular form of tumor. The multiple hemorrhagic sarcoma of the skin described by Kaposi may perhaps belong to this group. A small but interesting group of epithelial and neurologic tumors is characterized by an overgrowth of vascular elements. The so-called angiomas of the sweat ducts o r hemorrhagic basal-cell cancer, and tumors of the glomus described by Masson as angiomyoneuromas are of this type and may properly be included in a discussion of tumors of blood vessels.