by AK Team
Colorectal cancer is basically the cancer of the colon (large intestine) or the rectum. Sometimes the cancer remains limited to the colon and is known as the colon cancer.
Colon and rectum are the part of digestive system. The colon is also known as the large intestine and the rectum is a pathway or a passage connecting the colon and the anus.
Colorectal cancer in quiet common amongst individuals and is one of the leading causes of cancer deaths.
Not all types of colorectal cancer are deadly, if diagnosed in the initial stages. There are various treatments and medications available for curing it.
STUCTURE OF COLON AND RECTUM
- The colon and rectum are basically in simpler terms parts of large intestine.
- An U-shaped tube, made of muscles and is found below the stomach is known as the colon
- A shorter tube that is connected to the colon and also connects the colon with the anus, is the rectum
- The colon and rectum are surrounded by various other organs
- The longest part of the large intestine is the colon
- The function of the colon is to absorb water and nutrients from the digested food that it receives and to pass on the waste to the next part that is the rectum
- The colon of the large intestine has four parts : ascending colon, transverse colon, descending colon, sigmoid colon
- The ascending colon and the transverse colon are together known as the proximal colon
- The descending colon and the sigmoid colon are together known as the distal colon
- The lower and the last part of the large intestine that connects the sigmoid colon to the anus is called the rectum
- The waste that comes from the colon is stored here and then it is passed on to the anus and then finally outside the body
TYPES OF COLORECTAL CANCER
There are various common and rare types of colorectal cancer. Some of them are listed below :
Colorectal adenocarcinoma :
- Colorectal Adenocarcinoma is basically a colorectal cancer that develops in the epithelial lining of the cells.
- This line surfaces inside and outside the body.
- These develop in the lining of either the large intestine (colon) or the rectum that is the end of the colon
- Mucinous adenocarcinoma is a type of colorectal carcinoma that is made up of about 60 percent of mucus
- This mucus might be the reason of causing cancer
- Signet ring carcinoma is another type of colorectal carcinoma
- Signet carcinoma spreads less than mucinous carcinoma
Gastrointestinal carcinoid tumors :
- Gastrointestinal carcinoid tumors are the tumors that develop in the nerve cells that are known as neuroendocrine cells
- These cells help in regulating hormone production
- These kind of tumor cells are usually slow growing and they might develop either in the lungs or in the gastrointestinal tract
- These kind of cancer are rare nd do not spread that quickly
- Sometimes they also produce some kind of hormones that may eventually cause various symptoms depending on the type of hormone
Primary colorectal lymphomas :
- Primary colorectal lymphomas type of cancer usually develop in lymphatic system
- These develop in cells called lymphocytes
- These can develop in any part of the body which may include the spleen, thymus, digestive tract, bone marrow, etc.
- These type of cancers are more common in males than in females
- Primary colorectal lymphomas are a very rare type of colorectal cancer
Gastrointestinal stromal tumors :
- Gastrointestinal stromal tumors is a rate type of colorectal cancer which usually forms in the special cells that are found in the lining of the gastrointestinal tract
- These special type of cells are known as interstitial cells of Cajal ( ICCs)
- Mostly gastrointestinal stromal tumors are found in the stomach, in the colon and in the rectum
- This is also a very rare type of colorectal cancer
Familial adenomatous polyposis :
- Familial adenomatous polyposis are the most rarest type of colorectal cancer
- People who have these types of cancer usually develop many hundreds or thousands of colon or rectal polyps
SYMPTOMS OF COLORECTAL CANCER
The colorectal symptoms do not have specific noticeable symptoms in the initial stages, but over the period of time the symptoms might become noticeable.
Some of the symptoms are as follows :
- Bleeding from rectum usually bright red blood
- Dark brown or black stool because of bleeding in the stool
- Abdominal (belly) pain or cramping
- Weight loss that is unintended
- Narrowing of stool
- Change in bowel habits
- Feeling of having a bowel movement
- Abdominal discomfort
- Anemia that is usually unexplained
CAUSES OF COLORECTAL CANCER
The exact reason the leads to colorectal cancer is not known yet.
Usually the cells divide for replication. Sometimes these replications undergo some types of changes and the cells start growing abnormally. In this process the oncogenes are also stimulated to activate themselves due to certain factors. As the oncogenes activates themselves, the cells that were growing abnormally are now known as the cancerous cells.
These cells over a period of time grow and develop in various locations in the body and there are maximal chances of these spreading to other parts of the body as well.
Below listed are some of the risk factors that might lead to colorectal cancer eventually :
- A history of colorectal cancer or polyps ( either personal or family)
- Inflammatory intestinal conditions
- Inherited syndromes that might increase the risk of colon cancer
- Low – fiber diet
- High –fat diet
- An unhealthy lifestyle
- Alcohol abuse
- Radiation therapy for cancer
DIAGNOSIS OF COLON CANCER
If the doctor suspects that you might have colorectal cancer bases on your symptoms he might advise you to undergo the following diagnostic tests :
- A physical examination
- Colonoscopy (using a scope for the examination of inside of the patient’s colon)
- Biomarker testing of the tumor
- Some certain blood tests
- Computed tomography (CT or CAT ) scan
- Chest X –ray
- Magnetic resonance imaging (MRI)
- Positron emission tomography (PET) scan or PET – CT scan
TREATMENT OF COLORECATAL CANCER
The type of treatment (also read Cancer Treatment In India – All You Need To Know About ) a person receives for colorectal cancer entirely depends on the type of cancer a person is having, the stage at which he or she is currently and various other factors. Some of the treatments that one might undergo while thinking about to get a cancer treatment done for colorectal cancer are listed below :
- Minimally invasive surgery (also known as laparoscopic surgery)
- Endoscopic mucosal resection
- Polypectomy (removing polyps during a colonoscopy)
- Lymph node removal
- Partial colectomy
- Radiation therapy
- Targeted drug therapy
- Supportive (palliative) care