Stomach and oesophageal cancers
Dr Peter Barrow educates us on stomach and oesophageal cancers.
Stomach (gastric) cancer is a cancer that starts in any part of the stomach. Oesophageal cancer is a cancer that develops in the oesophagus – the muscular tube (food pipe) that connects the mouth to the stomach. While stomach cancer occurs in both males and females in almost equal numbers, oesophageal cancer is three to four times more common in men than in women.
One of the main risk factors for developing stomach cancer is an infection with a bacterium called Helicobacter pylori. This is the same bacterium associated with causing stomach and duodenal ulcers.
Smoking, obesity and a diet that includes large amounts of smoked food, salted fish, pickled vegetables, and food that contains nitrates and nitrites are also thought to be risk factors. Stomach cancer is also more common in people with type-A blood group.
Risk factors for oesophageal cancer include smoking and obesity. Acid reflux (and especially a condition, called Barrett’s oesophagus, which is caused by acid reflux) is also a major risk factor.
Increase and decrease
These cancers (stomach and oesophageal) make up about 2% of all cancers reported. The incidence of gastric cancer seems to be decreasing worldwide. This is possibly due to the increasing use of antibiotics treating the Helicobacter pylori infection.
The incidence, however, of cancer of the oesophagus is increasing. This is related to obesity and increasing age of population. About 80% of these cancers are diagnosed in people over the age of 60, with the average age of around 71 years old.
The early stages of stomach or oesophageal cancer may not cause any symptoms. They tend to be slow-growing and may grow for months to years before symptoms are noted. This means that they are often quite advanced at the time of diagnosis. Worrying symptoms include difficulty swallowing, new onset heartburn or reflux, and abdominal discomfort when eating. Unintentional weight loss, anaemia, and any symptoms suggestive of bleeding from the gut (vomiting blood or black dark stools) are also very troubling.
If any of these symptoms are present, a gastroscopy is usually the first test recommended. This is a test where a thin flexible fibre-optic tube with a ‘camera’ on the end is inserted through the food pipe (oesophagus) into the stomach.
If a cancer is suspected, a small biopsy is taken through the scope and sent to the pathologist to confirm the diagnosis. A gastroscopy is not normally painful, but may be quite uncomfortable, so is usually performed under sedation (a type of light anaesthetic).
Once a diagnosis of cancer is made, normally a CT scan (a special type of X-ray) is performed to see if the cancer has spread to any other part of the body. This is called staging.
A multi-disciplinary team (MDT) usually consisting of the endoscopist (the doctor who performs the scope), a pathologist (the doctor who looks at the biopsies under a microscope), a surgeon (a doctor who may operate), a radiologist (who helps to interpret the CT scans), an oncologist (the doctor who may use chemotherapy), and a radiation oncologist (a specialist doctor who uses radiation to treat cancer) usually meet to discuss the best way to treat the patient.
A MDT meeting is extremely important since all the progress in the different specialities of medicine and surgery. The ideal treatment for patients may be different for individual patients (i.e. some patients may need chemo or radiation before surgery, depending of the type of tumour (identified by the pathologist) or spread of tumour (guided by the radiologist). Therefore, input from all specialities is required to plan the best treatment for the individual patient to obtain the best outcome.
MEET OUR EXPERT – Dr Peter Barrow
Dr Peter Barrow is a consultant gastroenterologist. He has a special interest in advanced interventional endoscopy including endoscopic ultrasound. He works in a multi-disciplinary gastrointestinal unit at WITS Donald Gordon Medical Centre, and has extensive experience in cancer diagnosis and treatment.