Colorectal cancers (Early/locally advanced/metastatic)

Colorectal Cancer is the fourth most common cause of cancer death in the world. Approximately, 608,000 people die due to colorectal cancer every year, globally. However, due to the effective treatments, the rate of mortality has seen a decrease in the recent past.

It is said that colorectal cancer is a result of poor lifestyle habits such as unhealthy diet, drinking, smoking and lack of physical activity. In India, colorectal cancer is the fifth most common cancer. Relatively the risk of colorectal cancer is low in India but has been rising slowly. 

Colorectal Cancer is the development of cancer in the colon or rectum of the digestive system. These cancers can be named colon or rectum cancer depending on where it starts. Colon and rectal cancer are together referred to as “Colorectal Cancer”. Most colorectal cancer begins with polyps inside the colon or rectum and it may become cancerous over the course of time. Although not all polyps turn into cancer a few of them can take ugly forms. There are mainly 5 types of polyps. They are: 

  • Adenomatous polyps: Most common type, a small percentage becomes cancerous but almost all malignant polyps start as an adenomatous polyp. Fortunately takes a long time to turn into a cancerous lesion. 
  • Hyperplastic polyps: Common but extremely low risk for turning into cancers.
  • Serrated: Depending on their size and location in the colon they may become cancerous
  • Inflammatory polyps: Most often seen in IBD patients and also known as Pseudopolyps ( false polyps). these do not carry the risk of developing into cancers.
  • Villous Adenoma ( tubulovillous adenoma): Account for around 15 % of polyps in the colon and carry a high risk of turning into cancers. Polyps can be detected and safely removed during colonoscopy preventing them from turning cancerous.

During the beginning stages of colorectal cancer, cancer cells only spread to the inner layers of colon or rectum wall but not out of it. At the locally advanced stage, the cancer cells spread to nearby lymph nodes and but not yet to the other parts of the body. In the metastatic stage, cancer cells spread beyond the colon or rectum to other body parts by forming new tumours in and around different organs. 

Common treatments in curing colorectal cancer include surgery, chemotherapy, and radiation therapy. Depending on the stage of cancer the doctor decides which treatment to opt for. 

Symptoms of Colorectal Cancer 

  • Changes in bowel habits, that stay for more than a week.
  • Fatigue or tiredness or anaemia
  • Weight loss
  • Blood in stool
  • Rectal bleeding
  • Bloating and pain in the abdomen

Who are at the risk of developing colorectal cancer?

People with these factors are at the risk of colorectal cancer:

  • Older than 50
  • High alcohol consumption
  • A family history of colorectal cancer
  • Smoking
  • Overweight 
  • Lack of physical activity
  • A personal history of inflammatory bowel diseases
  • High consumption of red meat and processed foods
  • Long-standing Diabetes Mellitus ( Type II) patients also have are relatively increased risk
  • Post-transplant patients
  • Patients who have received hormone therapy or radiation to the pelvis for prostatic cancers

Types of cancer affecting the colon, rectum and abdominal region

Colonic Cancer- It is a type of cancer developed in the colon. Colon cancer begins with small growths called polyps inside the colon wall. Over time, these polyps transform into cancer cells. 

Rectal Cancer- Rectum is the last part of the intestine which connects the anus. Rectal cancer evolves when malignant cells start growing in the rectum.  

Most common histopathological type od Colorectal cancers are Adenocarcinoma.

Anal Cancer- The anus is a small tube at the end of the rectum from where our stool leaves out of the body. Anal cancer develops when abnormal cells grow in the anal canal. These are usually histologically different from Colorectal cancers in more commonly being Squamous cell carcinoma.

Peritoneal Surface Malignancy - Peritoneal surface malignancy is a type of cancer that affects the peritoneal cavity. The peritoneum is a membrane that lines the inside of the abdomen. Most cancers that affect the peritoneum originates from other parts of the body such as appendix, rectum, colon, stomach, and ovaries. Cytoreductive Surgery and chemotherapy, especially intraperitoneal chemotherapy (either Heated, normal temperature or aerosolised) reatments are used to cure peritoneal surface cancer.

Survival from cancer is directly related to the early detection and the type of cancer involved but overall is poor for symptomatic cancers, as they are totally advanced. It varies based on factors like early detection, age, health condition and stage of the disease. Studies have proved that survival rates for early-stage detection are about five times that of late-stage cancers. In the current era, with the advancement of the techniques and technologies and due to the increasing number of dedicated Colorectal cancer surgeons trained in managing advanced scenarios, even the survival of stage 4 disease is improving especially limited stage 4 where 'çure' can be offered.

Dr Shabnam Bashir is a dedicated Colorectal cancer surgeon trained from one of the highest volume cancer centers in the world and has vast experience in dealing with advanced cancers. She is a trained Laparoscopic and Robotic surgeon.

Authored by Dr. Shabnam Bashir

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About Dr. Shabnam Bashir


Dr. Shabnam Bashir has time and again proved her extensive and versatile expertise as a Colorectal Cancer Surgeon. This is validated by the successful cases of patients that she has dealt with.

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