Myomas are found in the esophagus, in the walls of the stomach, where they are frequently confounded with malignant tumors, in the prostate and wall of the bladder, and in connection with the skin. As soon as they give rise to inconvenience or to dangerous symptoms they are to be dealt with surgically, as no other treatment has proved of lasting benefit.

The rhabdomyomas deserve but brief description. The striated muscle fibers of which these tumors are composed have been often confused with spindle-shaped sarcoma cells. They are met with almost exclusively in the mixed tumors of the kidney under Teratomas.

Myoma or myofibroma is exceedingly likely to undergo sudden conversion into a form of growth entitling it to be called malignant myoma.

Angioma.

—Angiomas are tumors composed of bloodvessels, and group themselves under three headings, in accordance with the structure of the vascular system:

1. Capillary Angioma, or Nevus.

—Capillary angioma, or nevus, is the most common form of all, and is frequently seen in the skin and subcutaneous tissue. When the condition is spread over a relatively large area it gives rise to a discoloration known as port-wine mark, and called telangiectasis by the pathologists. The condition is often congenital or begins soon after birth. The color of the affected area determines whether the vessels belong to the venous or to the arterial system. These tumors may be found in all parts of the body, on the surface, on the submucous surfaces of the tongue, the inside of the mouth, the conjunctiva, and the vulva. The tendency is toward gradual increase in size; rarely, spontaneous contraction and obliteration occur.

2. Cavernous Tumors.

—These are similar in structure to the corpus cavernosum, and are called erectile tumors. They are common in connection with the skin, and are exaggerated forms of the variety first described, the vessels becoming not merely dilated but cavernous in arrangement. They occur occasionally in the tongue, in the voluntary muscles, and in the liver, and are noted very rarely in the mammæ, in the larynx, and subperitoneally.

A similar condition is met with in the so-called cavernous tumors which involve various organs, especially the thyroid and the liver. In these instances a part or the whole of the organ may be involved, and presents great increase in size and evidences of vascularity.