Cancer (Lat, a crab), the fourth sign in the zodiac, designated by the mark also, a constellation of stars formerly occupying the sign Cancer. The trppic of Cancer is the northern boundary of the torrid zone, where the sun is vertical at noon at the summer solstice.
Cancer, a malignant disease which attacks various organs of the human body, and tends to the progressive invasion of neighboring tissues and the final destruction of the parts; so called, because in some forms of the disease the fibrous ramifications extending in various directions were likened to the limbs of a crab. The most familiar and characteristic form of cancer is that which attacks the female breast, usually past the middle period of life. It first appears as local induration situated beneath the skin, in the glandular tissue of the organ, for the most part in the neighborhood of the nipple. It increases slowly in size, becomes adherent to the skin, and involves more and more of the substance of the breast. In most cases sharp lancinating pains are experienced at this time, sometimes causing much distress. When the glandular substance of the breast has become fully affected, it is also found to be adherent to the walls of the chest, so that it can no longer be' moved from side to side, and the skin over its whole surface is discolored, smooth in texture, raised in irregular knobs or eminences, and in spots red and tender.
The early hardness now yields to local softening, the skin gives way at some prominent point, and the ulcer thus formed shows no tendency to heal, but constantly enlarges, and discharges a dark-colored and foetid exudation. Subsequently the morbid growth involves the subjacent muscles, the ribs, and even the substance of the lungs. Internal cancer, however, is often developed as a secondary affection, without being directly continuous with the external growth. The patient may be gradually exhausted by the pain, discharge, and constitutional irritation dependent upon external cancer alone, or the fatal termination may be principally due to the secondary affection of the internal organs. The course of cancer is for the most part slow, requiring several years to pass through its successive stages. This is generally the case in cancer of the breast. In other forms, particularly where the morbid growth is softer and more vascular at the outset, it often terminates in a few months, or even weeks. Cancerous tumors, while still movable and well defined, are often removed by surgical operation with great relief to the patient.