“I Felt Great for Me, but Sad for that Other Gentleman”: What Happens When Lab Results Are Mixed Up?

​Incidents when a lab mixes up the biopsy results of two patients happen more often than providers think, according to a June 26, 2017, article in The New York Times. No comprehensive data are available on how often cancer biopsy samples are mixed up, the article said, but studies suggest such mistakes could happen to thousands of patients every year. In an error reported in a 2011 study, two men who had their prostates removed after being diagnosed with cancer turned out to be cancer free; the biopsy samples had been mishandled. One way around this, the article said, is to fingerprint and track test results with the patient's DNA. When the researchers in the 2011 study performed DNA analysis on 10,000 biopsies, they found that 27 were mislabeled and that 31 of 6,733 blood samples had been switched. That may not seem like a high percentage, but the impact of a wrong test result can be life altering and even deadly. While tracking the results with DNA could reduce these mix-ups, the article said, labs have been slow to adopt this practice because errors are relatively rare and the test is expensive.