High-Risk Individuals Often Underestimate Cancer Risk
People with inherited cancer syndrome underestimate risk with indeterminate genetic test
TUESDAY, July 21 (HealthDay News) -- Many individuals with Lynch syndrome underestimate their cancer risk if the results of their genetic test are unclear, according to a study published online July 20 in the Journal of Clinical Oncology.
Shilpa Grover, M.D., from the Dana-Farber Cancer Institute in Boston, and colleagues surveyed 159 individuals who had undergone genetic testing for Lynch syndrome, which is associated with germline mutations in mismatch repair genes, regarding their perceived risk of colorectal cancer.
The researchers found that 90 percent of the 100 individuals with a pathogenic mutation correctly estimated their colorectal cancer risk as "high" or "very high" compared with others their age. In contrast, only 62 percent of 37 individuals with an indeterminate test result correctly reported that their risk was increased. Individuals were significantly less likely to estimate an increased risk of colorectal cancer if they had been previously diagnosed with a Lynch syndrome-associated cancer (odds ratio, 0.1) or had previous indeterminate genetic results (odds ratio, 0.2).
"Patients at risk for Lynch syndrome with an indeterminate genetic test result may be falsely reassured," Grover and colleagues conclude. "It is important that health care providers continue to discuss the implications of uninformative results on lifetime cancer risk."
Several authors reported financial relationships with Myriad Genetics Laboratories.