Tumors of the blood vessels are numerically important among the neoplasms found in the human body. Many of these are benign angiomas of the body surfaces and merit little special clinical attention.
Hemangiomas of the capillary, or simple, type are characterized by an intricate arrangement of capillary blood vessels embedded in a variable amount of connective tissue stroma. They are usually congenital and may involve any part of the body except the cornea and cartilages. Although benign, they may be associated with malignant disease. They may be circumscribed or diffuse.
Cavernous hemangiomas are composed of blood spaces of irregular shapes and sizes which communicate with each other and are supported by a connective tissue framework. The spaces are lined with endothelium. The tumors are sometimes pulsating and erectile.
Many pathologists do not consider hemangiomas of either type as true tumors, classifying them instead as malformations. This is because many hemangiomas