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Colorectal Cancer : Definition
Western Medicine Chinese Medicine

Colorectal cancer affects the colon or the rectum. The colon is the major part of the large intestine. It consists of four parts, the ascending, transverse, descending and sigmoid colon.

Parts of the colon

After food is digested in the stomach and small intestine the digested material passes though the colon. The main function of the colon is to absorb water and some mineral salts from the digested material. The digested material enters the colon as a liquid. As the material passes through the colon water and mineral salts are absorbed back into the blood stream. By the time the digested material reaches the rectum it is no longer in a liquid-like form but in the form of feces. The rectum is a short muscular tube that connects the colon to the anus. Its function is to hold feces until they are expelled through the anus.

In the United States colorectal cancer is the third most commonly diagnosed cancer and third leading cause of cancer related deaths in both men and women. Among them, 90% of all cases are diagnosed after the age of 50. The occurrence of colorectal cancer is the same for both men and women up to the age of 50. After the age of 50 the incidence of colorectal cancer is higher in men than in women. The incidence of colorectal cancer throughout the world varies greatly. The incidence of colorectal cancer is highest among industrialized countries of Europe and North America.


Colorectal cancer is a Western medical term and is not specifically discussed in classical TCM texts. However, the main symptoms and signs of the disease are recorded in the following conditions:

Intestinal mass 'chang ji': refers to movable abdominal mass accompanied by pain or distention.
Bloody stools 'chang pi': refers to projectile bleeding from the rectum during defecation. This is due to the attack of wind evils in the stomach, leading to prolonged accumulation of dampness evils in the large intestine. It affects the distributing areas of Shao Yin meridians finally.
Abdominal mass 'zheng ji': the mass seen over the abdomen. When it is always palpable and immovable, accompanied by localized pain is named as "zheng", and that with intermittent occurrence, movable and accompanied by wandering pain is named as "ji".
Organ intoxication 'zang du': refers to a dark reddish bloody discharge due to prolonged organ damage. This causes inflammation of the lining of the large intestine due to accumulation of toxic material in the organs.
Hematochezia 'bian xue': passage of bloody stools; due to heat evils damaging the vessels and letting blood escape into the surrounding tissues. It also present when there is accumulation of virulent dampness evil in the large intestine, deficiency of spleen yang and stomach yang, or accumulation of wind evil at the yinfen level (the deeper level of the body).
Diarrhea 'xia li': Excessive and frequent evacuation of watery feces, usually indicating gastrointestinal distress or related disorder.
Rectal carcinoma blocking the anus 'suo gang zhi': a carcinoma causing narrowing of the rectum and anus, resulting in the discharge of slender feces and foul fluid, and accompanied by tenesmus (painful, ineffectual straining to empty the bowel).

All these TCM conditions present similar symptoms to colorectal cancer. The TCM physicians usually consider all of the above conditions during consultation.

TCM image of the large intestines