What is Colorectal Cancer?

Colorectal Cancer is characterized by the development of cancerous tissues in either the colon or the rectum. The colon and the rectum form a large muscular tube called the large intestine. The colon absorbs food and water and stores waste. The rectum is responsible for passing waste from the body. If cancer starts in the colon, then it is called colon cancer. If cancer stars in the rectum then it is called rectal cancer. Together they are often referred to as colorectal cancers. Colorectal cancers usually begin as small, benign (noncancerous) clumps of cells called an adenomatous polyp, which over time becomes colon cancers.

Types

There are many different types of breast cancer, some more common than others

Common forms of Colorectal cancer

• Adenocarinomas: the most common form of colon cancers. These are cancers that begin in the cells that make and release mucus and other fluids. They tend to start in the inner layer and then spread to deeper to other layers.
  
  
• Mucinous adenocarcinoma: made up mostly of mucus. The mucus can cause cancer cells to spread faster and become more aggressive than typical adenocarcinomas.
  
  
• Signet ring cell adenocarcinoma: very rare. It is typically aggressive and may be more difficult to treat.
  

Rare and less common forms of colorectal cancer include:

• Gastrointestinal Carcinoid Tumors
  
• Lymphomas
  
• Gastrointestinal Stromal Tumors
  
• Melanoma
  
• Sarcomas
  

Risk factors

It is important to know that having one or several o these risk factors does not necessarily mean that you will get colorectal cancer; in most cases the actual cause of colorectal cancer is not even known. However, researchers have found that several risk factors may increase a person's chance of developing colorectal polyps and colorectal cancer.

The following is a list of risk factors:

• Age: Usually affects people older than the age of 55. However, studies show increasing diagnosis in younger patients.
  
  
• Family and Personal History: If you have a history of adenomatous polyps (adenomas) there is a greater possibility of developing colorectal cancer, especially if the polyps are large or if they are many. If you have had colorectal cancer in the past, even when it has been completely removed you are more likely to develop new cancers in that area, especially if your first colorectal cancer occurred when you were younger.
  
  
• Racial and ethnic background: Studies show that African Americans have the highest diagnosis and mortality rates in the U.S.
  
  
• Inactive lifestyle: A sedentary lifestyle increases your chances of developing colorectal cancer.
  
  
• Obesity: If you are overweight, your chances of developing colorectal cancer increase.
  
  
• Smoking and Alcohol use: Smoking allows cancer-causing substances to be swallowed and increase the risk for the disease. Also, heavy alcohol can increase your risk for colorectal cancer.
  

Symptoms

In its early stages, it is possible that no symptoms of colorectal cancer appear. In fact, colon cancer can grow for years before causing any symptoms. Once symptoms appear, they will vary depending on the size and location of the cancer. Given this, it is best to get regular screenings rather than rely on colorectal cancer symptoms. The following is a list of common colorectal cancer symptoms, if you experience any of these please consult your doctor:

• Changes in bowel habits: This may an indicator for colorectal cancer.
  
  
• No bowel movements: Having a bowel movement less than three times a week can be your body's way of suggesting that you make some minor adjustments in diet or exercise. However, constipation can also be a symptom of a colon cancer.
  
  
• Rectal bleeding or blood in your stool: This is the most common colon cancer symptom. As the tumor grows, the passage of feces can cause the tumor to bleed. It is common to see bright red blood if the tumor is near de anus or toward the end of the colon, but it is more common for the blood to be hidden inside the stools and dry if the tumor is in the first part of the colon or the right side. The blood may also be separate from the feces or you may see it on the toilet paper.
  
  
• Abdominal bloating, cramps, or discomfort: A tumor can cause a bowel obstruction. Depending on the severity of the blockage, solids, liquids and even gas may be prevented from passing by. Painful cramps may also indicate that a tumor has perforated the bowel wall, this is a medical emergency.
  
  
• Weight loss: An unexpected weight loss accompanied by other symptoms can indicate colon cancer. The pain and discomfort caused by a tumor can lead to loss of appetite, which in turn results in weight loss. Also, a tumor can release chemicals that increase one's metabolism.
  
  
• Nausea or vomiting: This can occur for numerous reasons. In a small minority of cases it is due to a large tumor present in the right side of the colon that can prevent the digestive contents from moving forward and thus, cause food to back up, leading to nausea and possible vomiting.
  
  
• Anemia, weakness or fatigue: The presence of a tumor may cause iron deficiency anemia, this can make you feel extremely tired. Tumors tend to bleed, which results in a loss of iron.
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