Because gastrointestinal stromal tumors (GIST) are sensitive to the targeted small molecule therapy imatinib, oncologists tend to treat all patients with metastatic GIST with this drug. However, because this rare type of cancer is caused by different genetic mutations, imatinib does not help all patients equally.
To determine whose cancer may be most responsive, the National Comprehensive Cancer Network suggests that patients undergo genetic testing to identify each individuals’ tumor mutations. And yet, only 30 percent of patients have genetic testing at the time of diagnosis, likely due to concerns over cost and utility of testing, said Jason Sicklick, MD, professor of surgery in the Division of Surgical Oncology at University of California San Diego School of Medicine.
“We recommend that all patients with a new diagnosis of metastatic GIST undergo genetic testing prior to the initiation of first-line chemotherapy,” said Sicklick, surgical oncologist and co-leader of the Sarcoma Disease