Gastrointestinal cancer

Get peace of mind and prompt treatment for any worrying symptoms.

The gastrointestinal (GI) system consists of 7½ metres of tubing that’s responsible for transporting and processing food. Any worrying symptoms related to a part of this significant part of the human body should be investigated quickly to rule out cancer or confirm a diagnosis, so that treatment can begin as quickly as possible. 

What is GI cancer?

Gastrointestinal cancer is an umbrella term that includes oesophageal, gastric, colorectal, pancreatic, and liver cancers. All of these illnesses start when the cells in the lining of the GI tract mutate and grow into tumours, possibly spreading to lymph nodes and other organs. While there is still no definitive conclusion about the exact causes of cancer, we know that there are several risk factors depending on the specific cancer.

Symptoms of GI cancer

Because the GI system is so deeply internal, it can be difficult to catch GI cancers at their early stages. So, it is crucial to pay attention to your body and consult with a doctor if any of the following symptoms occur on a  frequent basis:

  • Stomach pain or cramping
  • Bloody stool or diarrhoea
  • Difficulty swallowing
  • Acid reflux or heartburn
  • Unexplained weight loss

The vast majority of people with these symptoms won’t have cancer, but it’s very important to get seen quickly if you are experiencing anything like this.

Dr Zeki’s work with GI cancer

Catching the disease early is the key to successful treatment, so it is crucial to see an experienced gastroenterologist, like Dr Zeki, if you frequently experience any of the symptoms above.

Dr Sebastian Zeki is a consultant gastroenterologist within the NHS at St Thomas’ Hospital in London, one of the country’s leading tertiary referral centres. He specialises in upper gastrointestinal physiology and endoscopy, including early detection, surveillance and treatment of gastrointestinal malignancies. 

Privately, Dr Zeki is easily accessible with consultations available within the prestigious HCA at the Shard Clinic, as well as diagnostic and treatment facilities like the Endoscopy Suite at London Bridge Hospital. 

The patient journey


As with all diseases, the method of diagnosis for GI cancer depends on the patient’s symptoms. Early detection is crucial in raising the patient’s chances of beating the cancer, so these procedures are essentially the first steps to recovery. 

  • An endoscopy checks the upper GI tract for tumours and abnormalities. It involves inserting a thin, flexible tube with a camera into the throat in order to take a peek inside of the oesophagus and stomach. While this test may be slightly uncomfortable, it is painless and administered along with a sedative or anaesthetic. 

  • A colonoscopy checks the lower GI tract for polyps, tumours, and abnormalities. It involves inserting a thin, flexible tube with a camera into the rectum in order to take a peek inside of the lower intestines.  While this test may be slightly uncomfortable, it is painless and administered along with a sedative or anaesthetic. 

  • Imaging (MRI, X-ray, ultrasound, or CT scan) checks for abnormal tissue within the GI system. These procedures are non-invasive and painless. 

  • A biopsy may be required to test a small sample of tissue for cancerous cells. Tissue collection is usually done during an endoscopy or a colonoscopy.


Modern medicine is always striving to find the least invasive and disruptive methods of helping patients retain their health. Many early GI cancers and their precursors can be removed with the endoscope. As long as GI cancers are caught early, then the ability to cure the patient with an endoscopic removal — often as a day case procedure — remains high. Dr Zeki specialises in the removal of early cancers with the endoscope. If the cancer is more advanced, then other treatments also exist, depending on the stage. 

Depending on the specific diagnosis, Dr Zeki will work alongside a wider team of specialists in order to make your journey to health as comfortable, effective, and personal as possible. Rest assured that all necessary steps will be taken to ensure you are treated as quickly as possible. 

Early detection is the key to GI cancer prevention

GI cancer FAQs

Can GI cancer be prevented?

While the exact cause of cancer is not yet established, there are certainly risk factors and environmental elements that contribute to the development of cancer. Maintaining a healthy diet, staying physically active, and avoiding harmful substances are all things you can do regularly to lessen your chances of cancer. Additionally, it is crucial to remain in tune with your body, pay attention to newfound pain or discomfort, and visit your doctor for frequent check-ups.

What are polyps, and what do they have to do with GI cancer?

A polyp is an outgrowth of tissue anywhere in the gastrointestinal tract. Some polyps have the potential to become malignant and lead to cancer, which is why they must be detected and removed as soon as possible. Polyps are detected during a colonoscopy or a gastroscopy (a type of endoscopy that investigates the oesophagus, stomach and small bowel).


Get in touch with us however you prefer

Dr Zeki offers consultations in Central London and looks forward to hearing from you.