Diagnostic medical tests, including those used to detect cancers, usually have to be examined by the FDA for safety and accuracy before getting approved. However, tests created by clinical laboratories (so-called laboratory-developed tests or LDTs) are exempt from this requirement. Such tests were originally intended for internal and research use only. However, with the rise of commercial laboratory testing companies, LDTs are reaching the general patient population. Because these tests have not been proven to deliver accurate and meaningful results, they could potentially mislead and harm patients. The FDA has drawn up a draft guidance document outlining better regulation for LDTs, but it is currently stalled in committee.