While they can arise anywhere along the GI tract, over half of gastrointestinal stromal tumors start in the stomach.
For the study, researchers from the University of California - San Diego (UCSD) School of Medicine analyzed US national cancer records covering 2001-11 from the Surveillance, Epidemiology, and End Results (SEER) database.
They say theirs is the first population-based study to look at links between a diagnosis of gastrointestinal stromal tumors (GISTs) and the development of additional cancers before and after a GIST diagnosis.
Their analysis shows that 1 in 5.8 patient with GIST will develop one or more additional cancers before or after their GIST diagnosis.
Malignant tumors most commonly found in addition to GIST included those of the genitourinary tract, breast, respiratory system and blood.
Senior author Jason K. Sicklick, assistant professor of surgery and surgical oncologist at UCSD Moores Cancer Center, says:
"Only 5% percent of patients with gastrointestinal stromal tumors have a hereditary disorder that predisposes them to develop multiple benign and malignant tumors."
He adds that their findings suggest patients who develop noninherited or sporadic GISTs may also be at risk of other cancers, but, the exact mechanisms are yet to be uncovered.
People with GIST diagnosis more likely to have other cancers
Cancer can arise anywhere in the gastrointestinal tract (GI) from the esophagus to the anus. Gastrointestinal stromal tumors (GISTs) are uncommon tumors of the GI tract.
GISTs start in very early forms of interstitial cells of Cajal (ICCs) which are found in the wall of the GI tract. These cells form part of the nervous system that controls digestion and other processes.
ICCs act like pacemakers in that they regulate the muscles that contract and move food and liquid along the GI tract.
While they can arise anywhere along the GI tract, over half of GISTs start in the stomach, and most of the others start in the small intestine.
The researchers found that - compared to the general US population - people with GISTs were 44% more likely to have other cancers before a GIST diagnosis, and 66% after.
Specifically, they identified that the cancers most likely to occur in addition to GIST were: other sarcomas, non-Hodgkin's lymphoma, carcinoid tumors, melanoma, esophageal, pancreatic, colorectal, hepatobiliary, nonsmall cell lung, prostate and renal cell cancers.
The team notes that GIST patients whose tumors were smaller than 10 cm were more likely to develop a second cancer than patients whose tumors were larger.
Also, patients with tumors smaller than 2 cm were the ones most likely to develop additional cancers before and after GIST diagnosis.
Might be an idea to screen patients with GISTs for other cancers
The authors say while more research needs to be done to find out how GIST is linked to other cancers, they believe their findings do have clinical implications.
Co-author James D. Murphy, an assistant professor of radiation oncology and a radiation oncologist at UCSD Moores Cancer Center, suggests:
"Patients diagnosed with gastrointestinal stromal tumors may warrant consideration for additional screenings based on the other cancers that they are most susceptible to contract."
The National Institutes of Health, the GIST Research Fund and a UC San Diego Academic Senate Health Sciences Research Grant helped fund the study.
Meanwhile, Medical News Today recently learned about a breakthrough that may lead to a blood test that predicts cancer years in advance.
Writing about their work in the new journal EBioMedicine, a team from Northwestern and Harvard Universities explains how a distinct pattern of changes in blood telomeres - protective ends of chromosomes that stop them unraveling - could predict cancer years before diagnosis.