That disturbing finding comes courtesy of a study presented this week at the 27th annual European Society of Medical Oncology Congress in Nice, France.
Swedish researchers calculated that the incidence of GIST is 16 cases per 1 million people annually. Their study was the first population-based examination of the incidence of GIST.
The researchers analyzed medical records and pathology reports of 1,500 people with abdominal tumors from 1983 to 2000. They found 400 cases of true GIST in that group. However, only 28 percent of the 400 received a GIST diagnosis originally.
In their study, the researchers used a special staining kit to identify GIST cases. This new form of immunohistochemistry makes it easier to identify GIST.
The researchers say being able to more accurately diagnose GIST is important because there is now an effective treatment for it -- imatinib, better known as Gleevec. GIST is resistant to chemotherapy and radiation.
The American Cancer Society has more information about gastrointestinal tumors.