A new study has found that a test that measures genomic changes in tissue samples taken from the thyroid can help identify which patients likely need diagnostic surgery for thyroid cancer and which do not. When a suspicious small growth or lump (called a nodule) is found in the thyroid, doctors perform a fine-needle biopsy so that the cells can be examined by a pathologist. But up to one-third of the time, pathologists can’t determine from the appearance of the cells whether the nodule is cancerous (an indeterminate result), explained the study’s lead investigator, Yuri Nikiforov, M.D., Ph.D., of the University of Pittsburgh Medical Center. Typically, people with indeterminate results go on to diagnostic surgery—the removal of the thyroid lobe that harbors the nodule. But most of these nodules turn out not to be cancer. So researchers have long been interested in developing molecular tests to assess indeterminate biopsy samples. The genomic test used in this new study was able to accurately identify indeterminate biopsy samples that, after surgery, were found to be benign, the researchers reported November 8, 2018 in JAMA Oncology. The test is one of several genomic classifiers for thyroid nodules that are starting to be used in the United States. The goal of developing this type of genetic test “is to safely prevent unnecessary surgeries,” Dr. Nikiforov said.