Colorectal Cancer

The wall of the colon consists of layers of tissue, muscle, and mucous membrane. Colorectal cancer originates from the mucosa, the colon’s innermost lining. It contains cells that produce and release mucous and other fluids. If these cells change or mutate, a colon polyp may be formed.

Colon polyps tend to turn malignant over time. Usually, it takes around ten years for a colon polyp to turn malignant. If left untreated or if it is not detected, the cancer spreads to outside of the colon through the layers of tissues and muscles. Colorectal cancer may also metastasise to other body parts through the blood vessels or lymph nodes.

Colorectal cancer is one of the commonest cancers affecting people in India. It is more commonly seen to occur in males as compared to females. Also, it is more commonly seen in people above fifty years of age. However, over the past decade, the number of younger people who have been affected with colorectal cancer have increased at an alarming rate.

Colorectal cancer can be asymptomatic. Even if symptoms are present, those are not specific to colon cancer. In other words, the symptoms of colorectal cancer are similar to those of less serious but similar conditions. Following are some of the most common symptoms of colorectal cancer:

• Presence of blood in the stool
  If you notice blood in your stool or if your stool appears bright red or darker in colour, you must talk to a healthcare provider. However, it is important to note that the presence of blood in stools does not necessarily point towards colorectal cancer. Some other medical conditions such as anal tears and harmorrhoids also present with similar symptoms. But, it is always wiser to talk to a doctor anytime you notice blood in your stools.
• Change in bowel habits
  If you have persistent diarrhoea or constipation, you must talk to a healthcare provider. You must also talk to a doctor if you feel like you still need to go to the toilet after you have just defecated.
• Pain in the abdomen
  If you have persistent pain in your abdomen without any known cause, you must talk to a healthcare provider. Although there are many other less serious conditions that cause abdominal pain, it is always wiser to talk to an expert medical professional if you have frequent unexplained abdominal pain.
• Bloating in the stomach
  Just like abdominal pain, bloating occurs due to a wide range of medical conditions. If your bloating lasts for more than a week or you notice that it is getting worse or is associated with other symptoms such as vomiting or blood in stools, you must talk to a healthcare provider.
• Unexplained weight loss
  It refers to a significant loss of body weight when you are making no effort to lose weight.
• Vomiting
  If you have been vomiting persistently for unknown reason or you have been vomiting periodically for the past twenty four hours, you must talk to a healthcare provider.
• Shortness of breath and fatigue
  Both of these are symptoms of anaemia, which in turn may be a sign of colorectal cancer.

Like other types of cancers, colorectal cancer occurs when the cells of the colon grow and multiply at an abnormally fast rate. All the cells are constantly growing, multiplying, and perishing. That is how the body maintains its health and functions properly. In colorectal cancer, the cells of the rectum and the colon keep on multiplying rapidly when they actually were supposed to die. Sometimes, these malignant cells arise from pre-existing colon polyps.

It is not known why some people develop such precancerous polyps. However, it is known that the presence of certain risk factors increases the chances of developing these precancerous polyps. Some of those risk factors include certain medical conditions and lifestyle choices. Even if you have one or more risk factors for developing colorectal cancer, it does not mean that you will develop the disease. It just indicates that you are at a higher risk for the same. Getting to know these risk factors will help you determine whether it’s a good idea for you to talk to your doctor about your susceptibility to developing colorectal cancer.

Following are some lifestyle choices that increase the chances of developing colorectal cancer:

• Smoking
  Consumption of tobacco products including using e-cigarettes and chewing tobacco increases your susceptibility to developing colorectal cancer.
• Excessive alcohol consumption
  Generally, males should have only two servings of alcoholic beverages per day, while women can have one serving per day. Even mild alcohol consumption can increase your susceptibility to developing colorectal cancer.
• Being obese
  Consuming a high-calorie, high-fat diet may make you obese and increase your colorectal cancer risk.
• A diet containing excessive amounts of red and processed meat
  Processed meat includes lunch meat and bacon sausage. It is recommended to limit processed meat and red meat to two servings per week.
• Lack of exercise
  Physical activity in any form may decrease the risk of developing colorectal cancer.

Following are some medical conditions that increase the risk of developing colorectal cancer:

• Inflammatory bowel disease
  Those who have medical conditions like Crohn’s colitis and chronic ulcerative colitis, that cause inflammation in the lining of the colon, have increased susceptibility to developing colorectal cancer. The risk is even higher if your inflammatory bowel disease has been lasting for more than seven years and if it affects large areas of the colon.
• Inherited conditions
  Certain inherited conditions like Familial Adenomatous Polyposis and Lynch syndrome may increase your risk of developing colorectal cancer. Colorectal cancer may also occur if you have genes inducing malignancy.
• Family history of colorectal cancer and other such cancers
  If a family member suffers from the condition, the chances of developing colorectal cancer increase. This includes your parents, children, and siblings. The risk is even higher if a close family member developed the condition before the age of 45 years.
• Family history of polyps
  If a family member of yours has an advanced polyp, your chances of developing colorectal cancer are increased. A polyp is said to be advanced if it appears to have malignant cells.
• Multiple polyps
  Those with multiple colon polyps including serrated polyps, adenomas, or other types of polyps are more susceptible to developing colon cancer and polyps.

Several tests are performed by healthcare providers to establish a diagnosis of colorectal cancer. Those tests include:

• Comprehensive metabolic panel (CMP)
• Complete blood count (CBC)
• Carcinoembryonic antigen assay (CEA): Normal cells and cancer cells release a substance called CEA into the bloodstream. High levels of CEA may indicate colorectal cancer.
• Computed tomography (CT) scan
• X-rays
• Positron emission tomography (PET) scan
• Magnetic resonance imaging (MRI) scan
• Biopsy
• Ultrasound

A screening test is used to look for malignant cells when the person doesn’t show signs and symptoms of malignancy. If any abnormality is revealed by screening tests, additional tests are required to be performed.

The most common screening test performed for colorectal cancer is a colonoscopy. Other tests include:

• Guaiac-based faecal occult blood test (gFOBT)
  This test is performed to look for blood in the stools that is not visible to naked eyes.
• Faecal immunochemical test (FIT)
  This test is also done to look for invisible blood in stools. Stool samples are taken and examined under a microscope.
• Faecal DNA test
  This test is done to look for genetic mutations and presence of blood in the stools.
• Virtual colonoscopy
  It refers to an X-ray performed to look for tumours, polyps, and ulcers in the rectum and the colon.
• Flexible sigmoidoscopy
  A flexible scope known as a sigmoidoscope is used to visualise the internal structures of the rectum and the colon.

Colorectal cancer is staged according to the TNM cancer staging system. It has five stages, three of which have three further sub-stages. Following are the stages of colorectal cancer:

• Stage 0
  This stage is referred to as carcinoma in situ. It means that there are precancerous or abnormal cells in the innermost layer of the colon wall called the mucosa.
• Stage I
  It means that the colorectal cancer has grown into the intestinal wall but has not metastasized into the nearby lymph nodes or beyond the muscular coat.
• Stage II
  It indicates that the cancer has spread into the deeper layers of the intestine but hasn’t metastasized to the surrounding lymph nodes. Stage II colorectal cancer is further divided into three types:
• Stage IIA
  The cancerous cells have invaded most of the colon wall but haven't spread to the outer layer of the wall.
• Stage IIB
  The malignant cells have spread to the outermost layer of the colon wall.
• Stage IIC
  The malignant cells have spread to a nearby organ.
• Stage III
  The cancerous cells have invaded the nearby lymph nodes. It is further divided into three sub-stages:
• Stage IIIA
  The malignant cells have invaded the first or second layers of the wall of the colon and has also involved upto four lymph nodes.
• Stage IIIB
  The malignant cells have involved more layers of the colon wall. However, only 1-3 lymph nodes have been affected. Stage IIIB colorectal cancer also refers to a cancer that involves fewer layers of the colon wall but has involved four or more lymph nodes.
• Stage IIIC
  The malignant cells have invaded the outermost layer of the colon in addition to four or more lymph nodes. Stage IIIC colon cancer also refers to a cancer that has spread to a nearby organ and one or more lymph nodes.
• Stage IV
  The malignant cells have spread to other body parts such as the lungs, liver, or the ovaries. This stage is also divided into three further stages:
• Stage IVA
  When the cancer has invaded one organ or distant lymph node.
• Stage IVB
  The cancer has invaded more than one distant lymph nodes.
• Stage IVC
  The cancer has involved distant lymph nodes, organs, and abdominal tissue.

The most common treatment used for colorectal cancer is surgery. Following are some procedures or surgeries performed to treat colon cancer:

• Polypectomy
  It is done to remove cancerous polyps.
• Partial colectomy
  Also known as colon resection surgery, it is a procedure where the surgeon resects the part of the colon containing the tumour along with some healthy tissue surrounding it. The healthy sections of the colon are the reconnected or anastomosed.
• Surgical resection with colostomy
  Here also surgeons resect that portion of the colon containing the tumour. However, they can’t reconnect the healthy parts of the colon here. A colostomy is performed instead. It is a procedure in which the bowel is moved to an opening in the wall of the abdomen where a bag is attached to collect the stools.
• Radiofrequency ablation
  In this procedure, heat is used to damage the malignant cells. Sometimes radiotherapy is used as an adjuvant therapy with surgery. This means that radiation is given before or after surgery to shrink the tumour or to destroy the remaining malignant cells.

Even though colorectal cancer can’t be completely prevented, steps can be taken to manage its risk factors. Some of those measures are given below:

• Avoid excessive use of tobacco: If you smoke, please quit. You can ask for help from a doctor who can guide you to smoking cessation programs.
• Take alcoholic beverages in moderation.
• Try to achieve and maintain a healthy weight.
• Maintain a healthy diet: Add good amounts of fresh fruits and vegetables to your everyday diet and reduce your consumption of high-calorie, high-fat food and red meat processed food. Your risk of developing colorectal cancer may be decreased by consuming coffee.
• Keep track of your family medical history: If any of your first degree relatives like a parent or a sibling is suffering from the disease, talk about it to your healthcare provider.
• Follow the screening guidelines for colorectal cancer: Talk to your doctor and try to know about the screening guidelines for colorectal cancer. If you have a family history of colorectal cancer or chronic irritable bowel disease, you may be recommended to start screening before the age of 45.

If diagnosed and treated at an earlier stage, colorectal cancer can be successfully treated. However, if the cancer has already advanced by the time it's diagnosed, treatment becomes a lot more challenging.

An important part of dealing with colorectal cancer is self-care. However, everyone’s situation is different. Those treated for early-stage colorectal cancers may be free from cancer. For those with advanced disease, the treatment might ease the symptoms but complete cure is not always possible. Such patients benefit from palliative care that focuses on dealing with the symptoms of the cancer and the side effects of treatment.

The follow-up for colorectal cancer depends on the stage of the disease. For example, those who undergo surgical treatment for stage 0 and 1 colorectal cancer may be recommended to have a colonoscopy one year post-surgery, repeat colonoscopy three years post-surgery and repeat it again five years post-surgery. Another colonoscopy is done years after unless the follow-up colonoscopies reveal signs of malignancy.

Patients who have been treated for stages II or III colorectal cancer, on the other hand, are required to see their doctor more often. They have to undergo more frequent CEA blood tests, colonoscopies, and imaging tests.

If you have been treated for colorectal cancer but are now noticing any changes indicating the recurrence of the disease, you must contact your healthcare provider as soon as possible.

If you are currently undergoing treatment for colorectal cancer, you must ask your doctor about the symptoms or side effects of the treatment that might require you to visit a healthcare provider. You may need to see a doctor if:

• Your chills don’t go away
• Your side effects are more severe than expected
• You have a fever of 100.4 F or higher
• Are experiencing severe abdominal pain
• Have persistent diarrhoea that causes dehydration

These days more people are taking time to undergo screening for cancers like colorectal cancer. Due to this, doctors are able to diagnose the disease at the right time and treat it accordingly. If any of your family members is suffering from the disease or you suspect having symptoms of colorectal cancer, you must contact a healthcare provider and seek necessary help. If you are located in Indore, you can visit the Centre for Cancer at Kokilaben Dhirubhai Ambani Hospital, Indore and get an appointment with expert cancer specialists who will guide you to the next step.

All the staff members at Kokilaben Dhirubhai Ambani Hospital, Indore are highly qualified and experienced in dealing with such procedures. Additionally, the centre is equipped with state-of-the-art infrastructure and modern machines to assist the medical staff in performing procedures and ensuring optimum outcomes for patients with colorectal cancer.