New York, May 3 (IANS): Patients suffering from gastrointestinal tumours are at increased risk of contracting other cancers, says a study.

One in 5.8 patients with gastrointestinal stromal tumours (GIST) will develop additional malignancies before and after their diagnosis, the results indicated.

Specifically, patients with GIST are more likely to develop other sarcomas, non-Hodgkin's lymphoma, carcinoid tumours, melanoma, colorectal, oesophageal, pancreatic, hepatobiliary, prostate and renal cell cancers.

"The research indicates that these patients may develop cancers outside these syndromes but the exact mechanisms are not yet known," said Jason Sicklick, assistant professor of surgery at the University of California's San Diego School of Medicine.

"Only five percent of patients with gastrointestinal stromal tumours have a hereditary disorder that predisposes them to develop multiple benign and malignant tumours," Sicklick added.

The researchers said further studies are needed to understand the connection between GIST and other cancers.

When compared to the United States population, the researchers found that people with GIST had a 44 percent increased prevalence of cancers occurring before a GIST diagnosis and a 66 percent higher risk of developing cancers after diagnosis.

The most common tumours were those of the genitourinary tract, breast, respiratory and blood.

"Patients diagnosed with gastrointestinal stromal tumours may warrant consideration for additional screenings based on the other cancers that they are most susceptible to contract," said co-author James Murphy from the University of California.

The study appeared in the journal Cancer.