Stomach bug treatment for cancer
Eradicating a common bug in people with stomach cancer can prevent the disease from recurring, research suggests.
Helicobacter pylori, proved to be the cause of most stomach ulcers, has also been linked with stomach cancer.
In a study of 550 people who had stomach cancer surgery, antibiotics which killed the bug cut the risk of a second cancer developing by two-thirds.
There will now be a trial of 56,000 British people to see if killing the bacterium stops the cancer developing.
H. pylori lives in the stomach, and accounts for up to 90% of duodenal ulcers and up to 80% of gastric ulcers.
It was famously linked with stomach ulcers by two Australian researchers - one of whom deliberately infected himself to prove the theory - who were awarded the Nobel prize for their discovery in 2005.
The World Health Organisation also classes the bacterium as a leading cause of stomach cancer.
Previous trials on eradicating H. pylori as a method of preventing further stomach cancers in patients who have undergone surgery have been conflicting.
But the latest study, done in Japan, found that the strategy could be very useful.
Patients with early stomach cancer underwent a procedure to remove the cancerous cells and surrounding tissue.
Half of them were then treated with a course of drugs designed to eradicate H. pylori - lansoprazole, amoxicillin and clarithromycin - and half received dummy pills and were then examined at six, 12, 24 and 36 months to see if the cancer had reappeared in a different site.
After three years, a second stomach cancer had developed in nine patients in the eradication group compared with 24 in the control group.
Overall, the risk of developing cancer was reduced by 65% with H. pylori treatment.
Study leader Dr Mototsugu Kato, from Hokkaido University Graduate School of Medicine said: "We believe that our data add to those from previous studies showing a causal relationship between H. pylori infection and gastric cancer, and also support the use of H. pylori eradication to prevent the development of gastric cancer."
Writing in the same issue of The Lancet, Dr Nicholas Talley, of Mayo Clinic Jacksonville, Florida, US said: "Preventing gastric cancer by eradicating H. pylori in high-risk regions should be a priority."
Henry Scowcroft, science information manager at Cancer Research UK, said: "This result adds to our understanding of the relationship between H pylori and stomach cancer, and to the debate on how we should treat people with this infection.
He added the charity was helping to fund a study to assess whether elimination of the bacteria could prevent cancer developing.
"The trial aims to recruit 56,000 people across the UK, treat any who show signs of H pylori infection, and follow them over 15 to 20 years to see if this treatment is effective."
About 21,500 Americans and 2,800 Canadians are diagnosed with cancer of the stomach each year. Stomach cancer is about twice as common in men as it is in women, and it occurs much more frequently in people who have experienced long-term infection with the Helicobacter pylori bacterium. Incidence of stomach cancer varies significantly between different populations. In Japan, for example, the disease is five times more common than it is in the United States.
Early Symptoms of Stomach Cancer
Early stomach cancer can have very mild symptoms, similar to indigestion symptoms. This includes feeling full after eating only a small meal, heartburn, stomach pain, nausea, vomiting and difficulty swallowing.
As the cancer advances, there may be additional symptoms such as weight loss, vomiting blood, or passing blood in the stools. This is not usually fresh, red blood, but dark blood. The blood loss may go unnoticed, but over a period of time, can cause anaemia.
When to seek medical advice
Many people suffer the symptoms of indigestion, and the vast majority do not have stomach cancer. But anyone who gets the following symptoms should seek medical advice:
vomiting for more than a few days, or immediately if it contains blood.
unexplained or sudden weight loss
persistent abdominal pain
It is also important to seek medical advice if any symptoms persist despite alterations to lifestyle, such as stopping smoking and eating more healthily, or if they start in someone aged 40 or over.
The doctor will ask about how and when the symptoms were noticed and perform a physical examination.
If the doctor suspects an ulcer or cancer then further investigations may be organised. These include the following:
blood test - including tests for anaemia and to assess liver function
barium meal - an X-ray test that involves drinking a fluid containing barium (a substance that shows up on X-rays) to show the stomach
gastroscopy - an investigation using a long thin telescope (an endoscope) that is passed through the mouth, down the gullet and into the stomach, so a doctor can inspect the lining of stomach. The same instrument can be used to take a sample from any areas that look suspicious (biopsy) which are sent for examination in a laboratory
scans - if cancer is suspected, discovering if or how far the cancer has spread (staging) may involve scans, including ultrasound, CT or MRI to look at the stomach, liver and lymph nodes. For more information, see the separate BUPA factsheets titled MRI scan and CT scan.
The only way to cure stomach cancer is to find it early and remove the tumour with surgery. If it has not spread outside the stomach, then an operation to remove either the whole stomach or just the affected part of it may be done.
In advanced cases, surgery will not cure the cancer but may be needed to treat symptoms such as vomiting, pain or bleeding.
Chemotherapy may be used after surgery to try to reduce the chances of the cancer coming back. The additional treatment is known as adjuvant chemotherapy. Radiotherapy is not usually used to try and cure stomach cancer, but is sometimes used to relieve symptoms if cancer has spread outside the stomach.
Eating a diet rich in fruit and vegetables (which contain antioxidant vitamins), not smoking and reducing alcohol intake will reduce the risk of stomach problems, including cancer. Be aware of the symptoms and seek medical advice promptly.
Regional Risk Stomach cancer
Researchers attribute these regional risk differences to dietary differences. Diets high in smoked or cured meats appear to increase the risk of stomach cancer. In the United States, stomach cancer is now only one-fourth as common as it was in 1930. This decline may be due, in part, to the increased use of refrigeration for food storage and decreased use of salted and smoked foods. (Early Symptoms of Stomach Cancer)
Approximately 90 to 95 percent of all cancers of the stomach are adenocarcinomas that develop in the lining of the stomach. Cancers of the immune tissue in the stomach wall, called gastric lymphomas, make up about 4 percent of all cancers of the stomach. Gastric sarcomas develop in the muscle tissue in the stomach wall, and account for only about 3 percent of all stomach cancers. (Early Symptoms of Stomach Cancer)
Like many cancers of the internal organs, stomach cancer rarely produces noticeable symptoms until it has spread to other sites in the body. When symptoms are present, they may include abdominal pain, heartburn, nausea, and vomiting. Stomach cancer is rarely detected early, and only about 20 percent of people diagnosed with stomach cancer in the United States live five years or longer.