Colon cancer is a type of cancer that occurs due to the uncontrolled growth of cancerous cells in the colon or rectum. It is also called colorectal cancer. It involves abnormal cell growth that can spread to another body part. Men and women both are at risk for this disease. However, men usually present earlier than women with this disease.

Causes of Colorectal Cancer

The exact cause of colorectal cancer is still unknown, but it is believed to result from a mutation in healthy cells. However, certain risk factors can increase the risk of developing this cancer.

- Frequently diagnosed in an individual who is aged 50 and above
- Having a history of ulcerative colitis for 8-10 years or more
- Obesity
- Family history with conditions such as familial adenomatous polyposis (FAP) and Hereditary nonpolyposis colorectal cancer (HNPCC)
- Consuming smoked meat
- Consuming excess of Red meat
- Gender
- Sedentary lifestyle

Risk factors of colorectal cancer

Several risk factors have been identified by researchers that may increase an individual's likelihood of developing colorectal cancer.

Certain risk factors can be addressed to decrease the chance of developing colorectal cancer:

- Smoking
- Physical inactivity
- Being overweight
- Heavy alcohol use

Risk factors that can not be addressed

- Having people with type 2 diabetes
- Inherited syndrome
- Inherited syndromes
- Familiar adenomatous polyposis (FAP)
- Hereditary nonpolyposis colon cancer (HNPCC)
- Turcot syndrome
- Peutz- jeghers syndrome

Symptoms of colorectal cancer

- The feeling of fullness in the abdomen
- Weakness
- Change in bowel habits such as constipation or change in stool
- Unexplained weight loss
- Stool that is narrower than usual
- Fatigue
- Lump in the abdomen
- Bleeding from rectum

Stages of Colorectal cancer

Stage 0 - This is the earliest stage where the cancer is in the mucosa, the inner layer of the colon.

Stage 1 - Cancer has begun to spread into the submucosa, the layer below the mucosa, and may spread into the muscularis propria, a muscle layer.

Symptoms of Colorectal cancer Stage 1:

- Constipation
- Diarrhoea
- Bleeding from rectum etc

Stage 2 - Stage 2 is further divided into different stages. In

In stage 2A the tumour has grown beyond the inner layer of the colon or rectum, called the muscularis propria, into the tissue between it and the outer layer, called the serosa. In either case, cancer has not spread to nearby lymph nodes or distant organs.

In stage 2B, the tumour has grown through the serosa or visceral peritoneum, the membrane that covers and supports the intestines and rectum. Cancer has spread beyond the colon or rectum and can affect nearby structures such as the bladder or prostate.

In Stage 2C, Nearby organs such as the bladder, prostate or uterus are observed with tumour circulation.

Symptoms of Colorectal cancer Stage 2:

- Abdominal pain
- Excessive gas
- Abdominal Cramps
- Excessive gas
- Blood in stool

Stage 3- In it, cancer cells in the colon or rectum have spread to nearby cancer cells. These stages are divided into stages 3A, 3B, and 3C, depending on the size of the tumour and the lymph nodes.

Stage 3A is characterised by cancer in the lymph nodes near the colon or rectum.

In stage 3B, the tumour can grow from the outer layer of the large intestine or rectum.

Stage 3C is the highest stage of stage 3 cancer. At this stage, cancer has spread beyond the colon or rectum and has affected four or more nearby lymph nodes but not distant ones.

Symptoms of Colorectal cancer Stage 3:

- Feeling that your bowl won't be empty
- Unintentional weight loss
- Excessive fatigue

Stage 4- In this stage, Metastatic colorectal is observed, which is cancer of the colon or rectum where cancer has spread to other parts of the body, such as the liver or lungs. There are different stages of cancer, depending on how far cancer has spread, Such as

- In stage 4A, cancer has spread to distant lymph nodes or organs.
- In stage 4B, cancer has spread to more than one organ.
- In stage 4C, cancer has spread to the peritoneum, the thin layer of tissue that covers the abdomen.

Symptoms of Colorectal cancer Stage 4:

- Jaundice
- Swollen hands and feet
- Blurry vision
- Bone fracture

Screening

Different types of Screening tests are recommended, such as:

- Colonoscopy
- Flexible sigmoidoscopy
- The guaiac-based faecal occult blood test
- Virtual Colonoscopy

Diagnosis of Colorectal Cancer

If your doctor notices anything suspicious during the exam or you show signs of colorectal cancer, your doctor may recommend a test to determine the cause.

- Medical history and physical history
- Blood tests such as:
  - Tumour markers
  - Liver enzymes
  - Complete blood count (CBC)
- Colonoscopy
- Biopsy
  - Gene tests
  - MSI and MMR tests
- Imaging test
  - Ultrasound
  - Chest X-ray
  - Magnetic resonance imagining (MRI)
  - Abdominal ultrasound

Treatment of Colorectal Cancer

Colorectal cancer treatment includes surgery, chemotherapy, radiation therapy, immunotherapy, and palliative care. Treatment depends on the tumour's location, its size, whether it has spread to nearby cancer cells or elsewhere in the body, etc.

- Surgical Resection: This is the most used and effective means of colorectal cancer treatment. The tumour and some surrounding tissue are removed through an operation. The type of surgery depends on the location and stage of the cancer.
- Laparoscopic Surgery: It is known as minimally invasive surgery. It involves minor abdominal incisions and inserting a small instrument and camera to visualise and operate internal organs.
- Colostomy: A colostomy is a surgical procedure involving an abdominal wall opening through which part of the intestine is brought to the skin surface. This creates a stoma, a small, red, round opening through which waste can exit the body. The waste is collected in a bag attached to the skin around the stoma. Colostomy can be temporary or permanent, depending on the patient's condition.
  - - A temporary colostomy is usually used after surgery to allow the colon or rectum to heal
    - In contrast, a permanent colostomy is used when it is impossible to reattach the colon to the rectum or anus.
- Radiotherapy: Radiotherapy is a treatment that uses high-energy X-rays or gamma rays to kill cancer cells. It is often used with a combination of chemotherapy to increase its effectiveness.
- Chemotherapy: Interveinal as well as oral chemotherapy , Targeted & Immunotherapy is used to treat various stages of colorectal cancer.

When to Consult a Doctor

You can also get in touch with the expert Oncology doctors at Narayana Healthcare based in your city to get immediate attention and medical support during injuries, health disorders or any other health concern.

FAQs

Q. Does colon cancer have a hereditary component? A. Yes, Colorectal cancer can have a hereditary component. Some people inherit specific genetic mutations that increase the risk of developing hereditary components.

Q. When is chemotherapy given? A. The time and duration of chemotherapy depend on the type and stage of the cancer.

Q. What are the side effects of colorectal treatment? A. Side effects of every treatment depend on the type of treatment and stage of colorectal cancer. A few side effects are:

- Fatigue
- Peripheral Neuropathy in very few cases

Q. How can I manage the side effects of treatment and maintain my quality of life during treatment? A. Steps you can take to help manage the side effects of treatment and to maintain your quality of life during colorectal cancer treatment

- Communicate with your healthcare team
- Stay hydrated
- Eat a healthy diet
- Exercise

Q. What is the five-year survival rate of Colorectal Cancer in India? A. The five-year survival rate of Colorectal Cancer in India is one of the lowest in the world at less than 40%.

The attached blog has been vetted by Dr Rohit Swami - Consultant Medical Oncology (Narayana Multispeciality Hospital Jaipur)