Causes & Risk Factors

Some factors increase individuals’ chances of developing GI cancer. Risk factors vary amongst the different types of GI cancers, and they generally include:

• Smoking
• Obesity
• Physical inactivity
• Heavy alcohol consumption
• History of GI cancer in family
• Pre-existing, or history of other conditions, e.g. Diabetes, Inflammatory Bowel Syndrome (IBS), Crohn’s Disease, Chronic Acid Reflux, Cirrhosis, and Chronic Viral Hepatitis B or C

Signs and Symptoms

Depending on the type of cancer, one may experience a combination of the following symptoms:

• Abdominal pain
• Appetite loss
• Bloatedness
• Blood in stool
• Constipation
• Change in stool colour
• Diarrhoea
• Fatigue and or/weakness
• Nausea and/or vomiting
• Heartburn
• Jaundice
• Unexplained weight loss
• Trouble swallowing

Stages

The stages for each type of cancer depends on the type of GI cancer. Generally, the stages for GI cancers are as follows:

Stages 1 and 2

The cancer is considered to be at its early stages, and a single modality of treatment may be sufficient.

Stages 3 and 4

Classified as cancer in advanced stages, multiple treatment modalities are required.

Stage 3 is considered locally advanced and multiple modality treatment may be required.
Stage 4 is when cancer has spread from the original site to other parts and is considered advanced (metastatic).

Screening & Diagnosis

In-depth screening and diagnosis depend on the type and location of cancer. Some screening and diagnostic procedures that can be done for most types of GI cancers are:

Imaging Tests

These tests, which include endoscopy such as gastroscope and colonoscopy, X-Rays, Magnetic Resonance Imaging (MRI), Computed Tomography (CT) and Positron Emission Tomography (PET) scans to detect any abnormal mass in gastrointestinal regions and for staging .

Biopsy

When the suspected cancerous tissue is located in a place that is difficult to reach, the doctor may suggest doing a biopsy, which involves making a small cut in the suspected area to extract samples.

Faecal Occult Blood Test (FOBT)

This procedure checks for blood in a patient’s faeces. If blood is found in the faeces, further testing is recommended, there can be other non-cancer factors such as hemorrhoids, that can cause bloody stool.

Endoscopic Ultrasound

This procedure enables the doctor to find out if small tumours are present. It involves inserting a thin flexible tube with an ultrasound probe into the small bowel through the patient’s mouth.

Flexible Sigmoidoscopy

The patient’s rectum and sigmoid is examined with a sigmoidoscope, which is a flexible, thin, and lighted tube. The doctor can then remove any polyps that are present and send them for further testing.

Proctoscopy

This procedure, which involves inserting a proctoscope (a long tube with a light) into the anus, enables the doctor to have a clear view of the anal canal, rectum, or sigmoid colon. The doctor may extract a small sample of tissue to conduct a biopsy.

Virtual Colonoscopy

A CT or X-Ray machine is used to capture images of the colon and rectum to detect polyps and tumours. Much less invasive than a conventional colonoscopy, this procedure may be followed up with the former if polyps and tumours are found.

Stool DNA test

This test analyses several DNA markers of colon-related cancers. It can be done at home – patients simply need to collect a stool sample, which the doctor will send to a lab for testing.

Treatment

Depending on the stage and type of GI cancer, a patient can be treated via one or a combination of these treatments.

Chemotherapy to shrink or kill the cancer cells
Radiation therapy to destroy cancer cells
Targeted therapy to stop the cancer cells from growing and spreading
Surgery to remove tumours, or perform transplants if possible

More specific information on treatment for the various types of GI cancers can be found here:

• Anal cancer
• Colorectal cancer
• Esophageal cancer
• Gallbladder and biliary tract cancer
• Gastrointestinal stromal tumours
• Liver cancer
• Pancreatic cancer
• Stomach cancer
• Small intestine cancer