Asian community at greater risk from stomach cancer; H. pylori blamed

January 22, 2014 | by

Stomach cancer is often considered a relatively rare cancer that affects predominantly older people.

H. pylori

Infection with Helicobacter pylori is a common precursor to gastric cancer, which disproportionately affects the Asian community.

However, what’s true for the majority of people in the United States is not true for the Asian population. Stomach cancer, or gastric cancer, is much more common among that community and tends to affect younger people. In fact, gastric cancer is twice as common among Asians and Pacific Islanders in Los Angeles County as it is among people nationwide.

“In most Asian countries, they have screening programs for gastric cancer,” said Joseph Kim, a surgical oncologist at City of Hope who specializes in gastrointestinal cancers.  “By age 40, most people are receiving regular endoscopies.”

However, such screening is less common in the United States, having never become as standard as preventive mammograms, colonoscopies and Pap smears. Insurance will often cover an endoscopy only if a patient shows additional risk factors, such as infection with Helicobacter pylori, or H. pylori.

The bacterium grows in the mucus layer that coats the inside of the stomach, and it’s found in the stomach of about two-thirds of the world population, especially in developing countries.

H. pylori secretes an enzyme that converts urea in the stomach to ammonia. This neutralizes the acidity of the stomach, making it a more welcoming environment for the bacterium. Further, the spiral shape of the bacterium allows it to burrow through the mucus layer and attach to the cells lining the inner surface of the stomach.

The bacterium, which can be detected with a breath test, is considered an important cause of gastric cancer, especially noncardia gastric cancer (stomach cancer in any area except the top portion where it joins the esophagus), according to the National Cancer Institute.

Southern California resident Donna An was diagnosed with stomach cancer at age 48. Several years before, she had suffered from soreness in her stomach and was diagnosed with H. pylori infection. Although similar symptoms later recurred, she didn't see a doctor right away and eventually was diagnosed with stomach cancer. After her diagnosis, she sought treatment at City of Hope, undergoing surgery, chemotherapy and radiation.

“I think the No.1 prevention is screening,” An said recently. “I thought, ‘Cancer, it’s not going to happen to me.’ A lot of people tell me they don’t want to see a doctor because they’re afraid something will come up. We’re all afraid of that. But get it done right away."

More screening is needed, Kim said, as is greater awareness of the risk within the Asian community. Through a partnership with Seoul National University Hospital, one of South Korea’s largest and most reputable teaching hospitals, Kim is exploring opportunities to offer some screenings for H. pylori to those communities most at risk.

As An said: "Even if you’re diagnosed with cancer, the best way is to find out at the early stage.”